0001104659-21-142014 | POS AM | XBRL Viewer

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying financial statements in conformity with accounting principles generally accepted in the United States of America, or U.S. GAAP. The Company’s condensed consolidated financial statements reflect the operations of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.

Unless otherwise noted, the Company has retroactively adjusted all common and preferred share and related price information to give effect to the Exchange Ratio established in the Merger Agreement.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in the financial statements include stock-based compensation costs, right-of-use, or ROU, assets, accruals for research and development activities, contingent earnout liability, fair value of common stock warrants, redeemable convertible preferred stock and income taxes. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

Unaudited Interim Condensed Consolidated Financial Statements

The accompanying interim condensed consolidated financial statements and the related footnote disclosures are unaudited. These unaudited interim financial statements have been prepared on the same basis as the audited financial statements, and in management’s opinion, include all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of September 30, 2021 and its results of operations for the three and nine months ended September 30, 2020 and 2021, and cash flows for the nine months ended September 30, 2020 and 2021. The results of operations for the three and nine months ended September 30, 2021 are not necessarily indicative of the results to be expected for the year ended December 31, 2021 or any other period. The December 31, 2020 year-end condensed consolidated balance sheet was derived from audited annual financial statements but does not include all disclosures from the annual financial statements.

Certain information and footnote disclosures normally included in consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2020 and the related notes included elsewhere in this prospectus, which provides a more complete discussion of the Company’s accounting policies and certain other information.

Other than the policies noted below, there have been no significant changes to the significant accounting policies disclosed in Note 2 of the audited consolidated financial statements as of and for the years ended December 31, 2019 and 2020 included elsewhere in this prospectus.

Common Stock Warrants

The Company assumed 5,000,000 publicly-traded warrants (“Public Warrants”) and 177,500 private placement warrants issued to AHAC Sponsor LLC (the “Sponsor”), Oppenheimer & Co. Inc. and Northland Securities, Inc, in connection with AHAC’s initial public offering (“Private Placement Warrants” and, together with the Public Warrants, the “Common Stock Warrants”). The Common Stock Warrants entitle the holder to purchase one share of the Company’s Common stock, par value $0.0001 (“Common Stock”), at an exercise price of $11.50 per share. The Public Warrants are publicly traded and are exercisable for cash unless certain conditions occur, such as the failure to have an effective registration statement related to the shares issuable upon exercise or redemption by the Company under certain conditions, at which time the warrants may be eligible for a cashless exercise. The Private Placement Warrants are non-redeemable for cash so long as they are held by the initial purchasers or their permitted transferees. If the Private Placement Warrants are held by someone other than the initial purchasers or their permitted transferees, the Private Placement Warrants are redeemable by the Company and exercisable by such holders on the same basis as the Public Warrants.

The Company evaluated the Common Stock Warrants to determine the appropriate financial statement classification upon the consummation of the Merger. The Common Stock Warrants are not mandatorily redeemable and are considered to be freestanding instruments as they are separately exercisable into common shares. As such, the Common Stock Warrants were not classified as liabilities under FASB ASC Topic 480, Distinguishing Liabilities from Equity (“ASC 480”). The Company then evaluated the Common Stock Warrants under FASB ASC Topic 815, Derivatives and Hedging.

The agreement governing the Common Stock Warrants includes a provision (“Replacement of Securities Upon Reorganization”), the application of which could result in a different settlement value for the Private Placement Warrants depending on their holder. Because the holder of an instrument is not an input into the pricing of a fixed-for-fixed option on the Company’s ordinary shares, the Private Placement Warrants are not considered to be “indexed to the Company’s own stock” and therefore are not classified in stockholders’ equity. As the Private Placement Warrants meet the definition of a derivative, the Company recorded these warrants as liabilities on the condensed consolidated balance sheet at fair value, with subsequent changes in their respective fair values recognized in the condensed consolidated statements of operations and comprehensive loss at each reporting date.

The Public Warrants are considered to be “indexed to the Company’s own stock”. The agreement provides that in the event of a tender or exchange offer made to and accepted by holders of more than 50% of the outstanding shares of the Company’s common shares, all holders of the Common Stock Warrants (both the Public Warrants and the Private Placement Warrants) would be entitled to receive cash for all of their Common Stock Warrants. As the Company has a single class of common stock, a qualifying cash tender offer of more than 50% of the Company’s common stock will always result in a change-in-control and would not preclude permanent equity classification of the Public Warrants. Based on this evaluation, the Company concluded that the Public Warrants meet the criteria to be classified within stockholders’ equity.

Contingent Earnout Liability

In connection with the Reverse Recapitalization and pursuant to the Business Combination Agreement dated as of February 17, 2021 by and among Legacy Humacyte, Merger Sub, and AHAC (the “Merger Agreement”), Legacy Humacyte equity holders are entitled to receive as additional merger consideration of up to 15,000,000 shares of the Company’s Common Stock (the “Contingent Earnout Shares”), comprised of two separate tranches of 7,500,000 shares per tranche, for no consideration upon the occurrence of certain triggering events, including a change of control event that is not solely indexed to the common stock. In accordance with ASC 815-40, as the earnout shares were not indexed to the common stock, they were accounted for as a liability at the Reverse Recapitalization date and subsequently remeasured at each reporting date with changes in fair value recorded as a component of other (expense) income, net in the condensed consolidated statements of operations and comprehensive loss.

The estimated fair value of the Contingent Earnout Shares was determined using a Monte Carlo simulation using a distribution of potential outcomes on a monthly basis over a ten-year period prioritizing the most reliable information available. The assumptions utilized in the calculation were based on the achievement of certain stock price milestones, including the current Company common stock price, expected volatility, risk-free rate, expected term and expected dividend yield.

The Contingent Earnout Shares are categorized as a Level 3 fair value measurement (see Fair Value Measurements accounting policy described below in Note 4) because the Company estimated projections over a ten-year period utilizing unobservable inputs. Contingent earnout payments involve certain assumptions requiring significant judgment and actual results can differ from assumed and estimated amounts.

Segments

The Company operates and manages its business as one reportable and operating segment. The Company is developing proprietary, bioengineered, acellular human tissues that are designed to be used in the treatment of diseases and conditions across a range of anatomic locations in multiple therapeutic areas. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for purposes of evaluating financial performance and allocating resources.

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services and is recognized in an amount that reflects the consideration that an entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. ASC 606 also impacts certain other areas, such as the accounting for costs to obtain or fulfill a contract.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

For contracts where the period between when the Company transfers a promised good or service to the customer and when the customer pays is one year or less, the Company has elected the practical expedient to not adjust the promised amount of consideration for the effects of a significant financing component.

Grant Revenue

The Company generates revenue primarily from government and other awarded grants that reimburse the Company for certain allowable costs related to research and development efforts. These grants include the following terms:

The Department of Defense grants are for an award of $4.0 million, all of which was recognized as revenue before the program ended, for work on bioengineered blood vessels for vascular trauma, which was awarded to the Company in September 2017 and ended in February 2020, and an award of $7.1 million for work to support human tissue engineered blood vessels for vascular reconstruction in the injured warfighter, which was awarded to the Company in August 2017 and is ongoing. The Company has recognized revenue of $0.6 million and $1.0 million during the three and nine months ended September 30, 2020,respectively, and $0.2 million and $1.1 million during the three and nine months ended September 30, 2021, respectively, for reimbursement of certain allowable costs related to these grants.

The National Institutes of Health grant is for $1.6 million for work to support bioengineered grafts for peripheral vascular disease, which was awarded to the Company in November 2013. The Company recognized $1.6 million for the reimbursement of certain allowable costs related to the grant before this program ended in 2020. The Company recognized $0.3 million during the three and nine months ended September 30, 2020, and no revenue during the three and nine months ended September 30, 2021, for reimbursement of certain allowable costs related to these grants.

The Company has determined that the grants are not within the scope of ASC 606 as they do not meet the definition of a contract with a customer. The Company has concluded that the grants meet the definition of a contribution and are nonexchange transactions and has applied the contribution accounting model in Subtopic 958-605, Not-for-Profit-Entities-Revenue Recognition by analogy.

The Company recognizes funding received from grants as revenue, rather than as a reduction of research and development expenses, because the Company is the principal in conducting the research and development activities and these grants are central to the Company’s ongoing operations. The Company recognizes revenue only after the qualifying expenses related to the grants have been incurred and it is reasonably assured that the expenses will be reimbursed and the revenue will be collectible. The related costs incurred are included in research and development expense in the Company’s condensed consolidated statements of operations and comprehensive loss.

Revenue from grants not within the scope of ASC 606 was $0.9 million and $1.4 million for the three and nine months ended September 30, 2020, respectively, and $0.2 million and $1.1 million for the three and nine months ended September 30, 2021, respectively.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. Total cash balances exceeded insured balances by the Federal Deposit Insurance Corporation as of December 31, 2020 and September 30, 2021. Cash equivalents are invested in highly rated money market funds invested only in obligations of the U.S. government and its agencies.

The majority of the Company’s revenue has been derived from government grants. The Company’s grants, which represented 10% or more of the Company’s total revenue during the three and nine months ended September 30, 2020 and 2021, or accounts receivable balance as of December 31, 2020 and September 30, 2021, are as follows:


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the three and nine months ended September 30, 2020 and 2021.

Other Risks and Uncertainties

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, successful discovery and development of its product candidates, the success of clinical trials and other studies for its product candidates, including for its ongoing V005 Phase II/III clinical trial and V007 Phase III clinical trial, the regulatory approval and commercialization of its HAVs and other product candidates, the expected size of the target populations for the Company’s product candidates, the degree of market acceptance of the HAVs, if approved, the availability of third-party coverage and reimbursement, development by competitors of new technological innovations, the ability to manufacture HAVs and other product candidates in sufficient quantities, expectations regarding the Company’s strategic partnerships, dependence on third parties, key personnel and the ability to attract and retain qualified employees, protection of proprietary technology and confidentiality of trade secrets, compliance with governmental regulations, the impact of the COVID-19 pandemic, the Company’s implementation and maintenance of effective internal controls, and the ability to secure additional capital to fund operations and commercial success of its product candidates.

Product candidates currently under development will require extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel, and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s commercialization efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales, and the Company may depend on certain strategic relationships to distribute its products, including the Company’s strategic partnership with Fresenius Medical Care Holdings, Inc., or Fresenius Medical Care, to sell, market and distribute its 6 millimeter HAV for certain specified indications.

Net Loss per Share Attributable to Common Stockholders

The Company follows the two-class method to compute basic and diluted net loss per share attributable to common stockholders when shares met the definition of participating securities. The two-class method determines net loss per common share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to share in the earnings as if all income for the period had been distributed. During periods of loss, there is no allocation required under the two-class method since the redeemable convertible preferred stock did not have a contractual obligation to share in the Company’s losses.

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless inclusion of such shares would be anti-dilutive. As the Company has only incurred losses, basic and diluted net loss per share is the same.

The potential shares of common stock that were excluded from the computation of diluted net loss per share for each period because including them would have had an antidilutive effect were as follows:


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204

The 15,000,000 Contingent Earnout shares are excluded from the anti-dilutive table for all the periods presented as such shares are contingently issuable until the share price of the Company exceeds specified thresholds that have not yet been achieved, or upon the occurrence of a change in control.

Impairment of Long-Lived Assets

The Company reviews the carrying value of property and equipment for indicators of possible impairment whenever events and circumstances indicate that the carrying value of an asset or asset group may not be recoverable from the estimated future net undiscounted cash flows expected to result from its use and eventual disposition. In cases where estimated future net undiscounted cash flows are less than the carrying value, an impairment loss is recognized equal to an amount by which the carrying value exceeds the fair value of the asset or asset group. The factors considered by management in performing this assessment include current operating results, trends and prospects, the manner in which the property is used, and the effects of obsolescence, demand, competition, and other economic factors. Based on this assessment, during the nine months ended September 30, 2020 and 2021, respectively, the Company concluded there were no such events or changes in circumstances requiring review of the carrying amount of the Company’s long-lived assets and there was no impairment at December 31, 2020 or September 30, 2021.

Recently Adopted Accounting Pronouncements

In August 2020, the FASB issued ASU No. 2020-06, “Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity” (“ASU 2020-06”), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. Either a modified retrospective method of transition or a fully retrospective method of transition is permissible for the adoption of this standard. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2020-06 as of January 1, 2021. The adoption of this ASU had no impact on the Company’s financial statements and related disclosures.

Recently Issued Accounting Pronouncements

In May 2021, the FASB issued ASU No. 2021-04, “Issuer’s Accounting for Certain Modifications or Exchanges of Freestanding Equity-Classified Written Call Options” (“ASU 2021-04”). The FASB issued this update to clarify and reduce diversity in an issuer’s accounting for modifications or exchanges of freestanding equity classified written call options (for example, warrants) that remain equity classified after modification or exchange. ASU 2021-04 is effective for all entities for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. An entity should apply the amendments prospectively to modifications or exchanges occurring after the effective date of the amendments. The Company is currently evaluating the effect of this update on its financial statements.

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP.

Reverse Recapitalization

On August 26, 2021 (the “Closing Date”), Alpha Healthcare Acquisition Corp. (“AHAC”) consummated a merger pursuant to which Hunter Merger Sub, Inc. (“Merger Sub”), a Delaware corporation and wholly owned subsidiary of AHAC, merged with Humacyte, Inc., a Delaware Corporation (“Legacy Humacyte”), with Legacy Humacyte surviving the Merger as a wholly-owned subsidiary of AHAC (such transactions, the “Merger,” and, collectively with the other transactions described in the Business Combination Agreement dated as of February 17, 2021 by and among Legacy Humacyte, Merger Sub, and AHAC (the “Merger Agreement”), the “Reverse Recapitalization”). As a result of the Merger, AHAC was renamed Humacyte, Inc. (“New Humacyte”) and Legacy Humacyte was renamed Humacyte Global, Inc.

Unless otherwise noted, the Company has retroactively adjusted all common and preferred share and related price information to give effect to the Exchange Ratio of approximately 0.26260 established in the Merger Agreement.

Segments

The Company operates and manages its business as one reportable and operating segment. The Company is developing proprietary, bioengineered, acellular human tissues that can be used in the treatment of diseases and conditions across a range of anatomic locations in multiple therapeutic areas. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for purposes of evaluating financial performance and allocating resources.

Comprehensive loss

Comprehensive loss includes net loss as well as other changes in stockholders’ deficit that result from transactions and economic events other than those with stockholders. There was no difference between net loss and comprehensive loss for the years ended December 31, 2019 and 2020.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in the financial statements include stock-based compensation costs, right-of-use, or ROU assets, accruals for research and development activities, fair value of common stock, useful lives of property and equipment, redeemable convertible preferred stock and income taxes. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

2. Summary of Significant Accounting Policies (continued)

Cash and Cash Equivalents

The Company considers all short-term, highly liquid investments purchased with an original maturity of three months or less at the date of purchase to be cash equivalents. Cash deposits are held with financial institutions with investment-grade ratings in the United States of America, or US. Cash deposits typically exceed federally insured limits. As of December 31, 2019 and 2020, cash and cash equivalents consisted of cash on deposit with banks denominated in US dollars and investments in money market funds.

Redeemable Convertible Preferred Stock

The Company analyzes all issued equity instruments to determine the appropriate accounting and classification. The Company evaluates its equity instruments under Accounting Standards Codification, or ASC 480, Distinguishing liabilities from equity, to determine whether the instrument embodies an obligation of the Company and, if not, the appropriate classification within temporary or permanent equity. Equity instruments that are classified as temporary equity will have at least one of the following characteristics: redemption at a fixed or determinable price on a fixed or determinable date or dates, redemption at the option of the holder, or any condition of redemption or liquidation which is not solely within the control of the Company without regard to probability.

The Company records equity instruments that are classified as temporary equity at fair value upon issuance, net of issuance costs. The Company accretes the carrying value of its redeemable convertible preferred stock to the redemption or liquidation amount once the Company has determined that it is probable that it will become redeemable or be liquidated. The accretion will be recorded as charges against additional paid-in capital until the additional paid-in capital balance is reduced to zero. At that time, additional accretion adjustments will be recorded as additions to accumulated deficit.

The Company also analyzes instances where the equity instrument has a conversion feature pursuant to ASC 815, Derivatives and hedging, to determine whether the embedded conversion feature should be bifurcated from the equity instrument and accounted for separately. As of December 31, 2019 and 2020, the Company did not have any instruments that have been recognized as derivative liabilities with respect to its outstanding redeemable convertible preferred stock.

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In 2014, the Financial Accounting Standards Board, or FASB issued Accounting Standards Update No. 2014-09, Revenues from Contracts with Customers (Topic 606), or ASC 606. The new guidance became effective January 1, 2019 for private companies with early adoption allowed. The Company adopted ASC 606 on January 1, 2019 using the modified-retrospective adoption method for all contracts that were not completed as of the date of adoption. Under the modified-retrospective method, there was no cumulative effect of applying the standard as of January 1, 2019.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

2. Summary of Significant Accounting Policies (continued)

Grant Revenue

We generate revenue primarily from government and other awarded grants that reimburse us for certain allowable costs related to research and development efforts. The Company has determined that the grants are not within the scope of ASC 606 as they do not meet the definition of a contract with a customer. The Company has concluded that the grants meet the definition of a contribution and are nonexchange transactions and has applied the contribution accounting model in Subtopic 958-605, Not-for-Profit-Entities-Revenue Recognition by analogy.

The Company recognizes funding received from grants as revenue, rather than as a reduction of research and development expenses, because the Company is the principal in conducting the research and development activities and these grants are central to the Company’s ongoing operations. The Company recognizes revenue only after the qualifying expenses related to the grants have been incurred and it is reasonably assured that the expenses will be reimbursed and the revenue will be collectible. The related costs incurred are included in research and development expense in our statements of operations and comprehensive loss.

Revenue from grants not within the scope of ASC 606 was $6.2 million and $1.5 million for the years ending December 31, 2019 and 2020, respectively.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. Total cash balances exceeded insured balances by the Federal Depository Insurance Corporation as of December 31, 2019 and 2020. Cash equivalents are invested in highly rated money market funds invested only in obligations of the US government and its agencies.

The majority of the Company’s revenue has been derived from government grants. The Company’s grants which represented 10% or more of the Company’s total revenue during the years ended December 31, 2019 and 2020 or accounts receivable balance as of December 31, 2019 and 2020 are as follows:


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the years ended December 31, 2019 and 2020.

2. Summary of Significant Accounting Policies (continued)

Other Risks and Uncertainties

Net Loss per Share Attributable to Common Stockholders

The Company applies the two-class method to compute basic and diluted net loss per share attributable to common stockholders when shares meet the definition of participating securities. The two-class method determines net loss per share for each class of common and redeemable convertible preferred stock according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income (loss) available to common stockholders for the period to be allocated between common and redeemable convertible preferred stock based upon their respective rights to share in the earnings as if all income (loss) for the period had been distributed. During periods of loss, there is no allocation required under the two-class method since the redeemable convertible preferred stock does not have a contractual obligation to share in the Company’s losses.

2. Summary of Significant Accounting Policies (continued)

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless inclusion of such shares would be anti-dilutive. Since the Company has only incurred losses, basic and diluted net loss per share is the same. Securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share are as follows:


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Fair Value of Financial Instruments

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants at the measurement date. ASC 820, Fair Value Measurement and Disclosures, establishes a hierarchy whereby inputs to valuation techniques used in measuring fair value are prioritized, or the fair value hierarchy. There are three levels to the fair value hierarchy based on reliability of inputs, as follows:

●

Level 1—Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets.

●

Level 2—Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

●

Level 3—Unobservable inputs in which little or no market data exists, therefore requiring the Company to develop its own assumptions.

The Company evaluates assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level at which to classify them for each reporting period, utilizing valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The determination requires significant judgments to be made by the Company.

The Company’s cash equivalents are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. The carrying values of other receivables, accounts payable and accrued expenses as of December 31, 2019 and 2020 approximated their fair values due to the short-term nature of these items.

2. Summary of Significant Accounting Policies (continued)

Property and Equipment, Net

Property and equipment, net are recorded at cost less accumulated depreciation. Expenditures for major additions and improvements are capitalized and minor replacements, maintenance, and repairs are charged to expense as incurred. When property and equipment are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet accounts and any resulting gain or loss is included in the results of operations for the respective period. Depreciation is calculated using the straight-line method over the estimated useful lives of the related assets. The estimated useful lives for significant asset categories are as follows:


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Impairment of Long-Lived Assets

The Company reviews the carrying value of property and equipment for indicators of possible impairment whenever events and circumstances indicate that the carrying value of an asset or asset group may not be recoverable from the estimated future net undiscounted cash flows expected to result from its use and eventual disposition. In cases where estimated future net undiscounted cash flows are less than the carrying value, an impairment loss is recognized equal to an amount by which the carrying value exceeds the fair value of the asset or asset group. The factors considered by management in performing this assessment include current operating results, trends and prospects, the manner in which the property is used, and the effects of obsolescence, demand, competition, and other economic factors. Based on this assessment, there was no impairment at December 31, 2019 and 2020.

Income Taxes

Income taxes are computed using the asset and liability approach that requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company’s financial statements. In estimating future tax consequences, the Company considers all expected future events other than enactment of changes in tax laws or rates. A valuation allowance is recorded, if necessary, to reduce net deferred tax assets to their realizable values if management does not believe it is more likely than not that the net deferred tax assets will be realized. As of December 31, 2019 and 2020, the Company has recorded a full valuation allowance against its deferred tax assets.

2. Summary of Significant Accounting Policies (continued)

The Company recognizes the benefit of an income tax position only if it is more likely than not (greater than 50%) that the tax position will be sustained upon tax examination, based solely on the technical merits of the tax position. Otherwise, no benefit can be recognized. Assessing an uncertain tax position begins with the initial determination of the sustainability of the position and is measured at the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement. As of each balance sheet date, unresolved uncertain tax positions must be reassessed. Additionally, the Company must accrue interest and related penalties, if applicable, on all tax exposures for which reserves have been established consistent with jurisdictional tax laws.

The Company has analyzed its filing positions in all significant Federal and state jurisdictions where it is required to file income tax returns, as well as open tax years in these jurisdictions. As of December 31, 2019 and 2020, the Company has determined that no uncertain tax positions would have a material impact on the financials statements of the Company. The Company is no longer subject to Federal, state, and local tax examinations by tax authorities for years before 2017 although carry-forward attributes that were generated prior to 2017 may still be adjusted upon examination by the taxing authorities if they either have been or will be used in a future period. No income tax returns are currently under examination by taxing authorities.

As of December 31, 2019 and 2020, the Company had not recorded any amounts for unrecognized tax benefits. The Company’s policy is to recognize interest and penalties related to uncertain tax positions in the provision for income taxes. As of December 31, 2019 and 2020, the Company had no accrued interest or penalties related to uncertain tax positions, and no amounts had been recognized in the Company’s statements of operations and comprehensive loss.

Intellectual Property

The Company seeks to protect its intellectual property by filing patent applications in the United States and abroad related to novel technologies and product candidates that it views as important to its business. The patent positions of biotechnology companies generally, including the Company’s patent positions, is highly uncertain and involves complex legal and factual questions for which legal principles remain unresolved. Patent costs have been expensed as incurred as general and administrative expense.

Research and Development

The Company expenses research and development costs as operating expenses as incurred. Research and development expenses consist primarily of:

●

salaries and related overhead expenses for personnel in research and development functions, including stock-based compensation and benefits;

●

fees paid to consultants and CROs, including in connection with clinical trials, and other related clinical trial fees, such as for investigator grants, patient screening, laboratory work and statistical compilation and analysis;

●

allocation of facility lease and maintenance costs;

●

depreciation of leasehold improvements, laboratory equipment and computers;

●

costs related to purchasing raw materials for and producing product candidates for clinical trials;

●

costs related to compliance with regulatory requirements;

●

costs related to the manufacturing scale-out initiative; and

●

license fees related to in-licensed technologies.

2. Summary of Significant Accounting Policies (continued)

Accrued Research and Development

The Company has entered into various agreements with CROs and a CMO, which conduct preclinical studies and clinical trials and contract manufacturing activities. The Company’s research and development accruals are estimated based on the level of services performed, progress of the studies, including the phase or completion of events, and contracted costs. The estimated costs of research and development provided, but not yet invoiced, are included in accrued expenses on the balance sheet. If the actual timing of the performance of services or the level of effort varies from the original estimates, the Company will adjust the accrual accordingly. Payments made under these arrangements in advance of the performance of the related services are recorded as prepaid expenses and other current assets until the services are rendered. The Company terminated its agreement with its CMO on March 6, 2020 but will continue to rely on its CMO to store and ship HAV inventory until such time as its HAV inventory is fully depleted. As of December 31, 2020, the inventory value held at the CMO is immaterial.

Stock-Based Compensation

The Company accounts for stock-based compensation for employees and non-employees measured at grant date, based on the fair value of the award. The Company measures the fair value of awards granted using the Black-Scholes option pricing model and recognizes the expense over the requisite service period using the straight-line method. Option valuation models, including the Black-Scholes option-pricing model, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the grant-date fair value of an award. These assumptions include the risk-free rate of interest, expected dividend yield, expected volatility, the expected term of the award, and the fair value of the underlying common stock on the date of grant. Forfeitures are accounted for as they occur.

Leases

Effective January 1, 2019, the Company accounts for its leases under ASC 842, Leases. The Company determines if an arrangement is or contains a lease and the classification of that lease at inception of a contract. The Company’s operating lease assets are included in “operating lease right-of-use assets, net”, and the current and non-current portions of the operating lease liabilities are included in “operating lease obligation, current portion”, and “operating lease obligation, net of current portion”, respectively, on the balance sheets. The Company’s finance lease assets are included in “finance lease right-of-use assets, net”, and the current and non-current portions of the finance lease liabilities are included in “finance lease obligation, current portion”, and “finance lease obligation, net of current portion”, respectively, on the balance sheets.

Under this guidance, arrangements meeting the definition of a lease are classified as operating or finance leases, and are recorded on the balance sheet as both a right-of-use asset and lease liability, calculated by discounting fixed lease payments over the lease term at the rate implicit in the lease or the Company’s incremental borrowing rate. Lease right-of-use assets and lease obligations are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. Operating lease right-of-use assets are adjusted for (i) payments made at or before the commencement date, (ii) initial direct costs incurred, and (iii) tenant incentives under the lease. As the implicit rate for the operating leases were not determinable, the Company used an incremental borrowing rate based on the information available at the respective lease commencement dates in determining the present value of future payments. The incremental borrowing rate represents the interest rate the Company would expect to incur at lease commencement to borrow an amount equal to the lease payments on a collateralized basis over the term of a lease. The Company determined the incremental borrowing rate by considering various factors, such as its credit rating, interest rates of similar debt instruments of entities with comparable credit ratings, the lease term and the currency in which the lease was denominated. The Company considers a lease term to be the noncancelable period that it has the right to use the underlying asset, including any periods where it is reasonably certain the Company will exercise any option to extend the contract.

2. Summary of Significant Accounting Policies (continued)

Lease expenses for minimum lease payments for operating leases are recognized on a straight-line basis over the lease term. Amortization expense of the right-of-use asset for finance leases is recognized on a straight-line basis over the lease term and interest expense for finance leases is recognized based on the incremental borrowing rate. Lease liabilities are increased by interest and reduced by payments each period, and the right of use asset is amortized over the lease term.

In calculating the right-of-use assets and lease liabilities, the Company has elected to combine lease and non-lease components for all asset classes. The Company excludes short-term leases, if any, having initial terms of 12 months or less from the new guidance as an accounting policy election, and recognizes rent expense on a straight-line basis over the lease term.

Prior to the adoption of ASC 842 on January 1, 2019 the Company was deemed to be the accounting owner of leased space during the construction of its headquarters in a build-to-suit arrangement. Upon substantial completion of construction in June 2018, the Company assessed the facility for sale-leaseback criteria qualification. The Company determined that the transaction did not meet the requirements of a sale-leaseback due to the Company’s continuing involvement in the leased facility. As such, the facility was accounted for as an asset financing, with the building asset and related facility financing obligation remaining on the Company’s balance sheet. The Company availed itself of the practical expedients provided under the ASU and its subsequent amendments regarding identification of leases, lease classification, indirect costs, and the combination of lease and non-lease components. Upon adoption of ASC 842, the Company removed the building assets and facility financing obligation, under the failed sale leaseback, for its headquarters lease from its financial statements, with a corresponding adjustment (addition) to accumulated deficit of $1.9 million, and recorded a finance lease liability and corresponding right-of-use asset, each for $27.6 million in connection with the headquarters lease. In addition, the adoption of this guidance resulted in the recognition of operating right-of-use assets and operating lease liabilities of $0.9 million as of January 1, 2019, which included the lease of the underlying land associated with its headquarters.

The cumulative effect of initially applying the new lease guidance on January 1, 2019 is as follows:


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

2. Summary of Significant Accounting Policies (continued)

Recently Adopted Accounting Pronouncements

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement, which makes a number of changes to add, modify or remove certain disclosure requirements associated with the movement amongst or hierarchy associated with Level 1, Level 2 and Level 3 fair value measurements. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted upon issuance of the update. The Company adopted ASU 2018-13 as of January 1, 2020. The adoption of this ASU did not have a material impact on its financial statements and related disclosures.

Recently Issued Accounting Pronouncements

In August 2020, the FASB issued ASU No. 2020-06, “Debt-Debt with Conversion and Other Options (Subtopic 470 – 20) and Derivatives and Hedging-Contracts in Entity’s Own Equity (Subtopic 815 – 40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. Either a modified retrospective method of transition or a fully retrospective method of transition is permissible for the adoption of this standard. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, with early adoption permitted. The Company plans to adopt the standard effective January 1, 2021 and is currently evaluating the impact of this standard on its financial statements and related disclosures.

Property and Equipment, Net

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

5. Property and Equipment, Net

Property and equipment, net consist of the following:


	December 31,		September 30,
($ in thousands)	2020		2021

Scientific equipment	$	27,412	$	27,578
Computer equipment		149		154
Software		335		335
Furniture and fixtures		988		988
Leasehold improvements		26,355		26,355
		55,239		55,410
Accumulated depreciation		(14,261)		(18,911)
Property and equipment, net	$	40,978	$	36,499

Depreciation expense totaled $1.6 million and $4.7 million for the three and nine months ended September 30, 2020, respectively, and $1.5 million and $4.7 million for the three and nine months ended September 30, 2021, respectively. All long-lived assets are maintained in the United States.

3. Property and Equipment, Net

Property and equipment, net consist of the following:


	As of December 31,
($ in thousands)	2019		2020

Scientific equipment	$	27,822	$	27,412
Computer equipment		218		149
Software		340		335
Furniture and fixtures		988		988
Leasehold improvements		26,337		26,355
		55,705		55,239
Accumulated depreciation		(8,417)		(14,261)
Property and equipment, net	$	47,288	$	40,978

Depreciation expense totaled $4.7 million and $6.3 million for the years ended December 31, 2019 and 2020, respectively. All long-lived assets are maintained in the United States.

Accrued Expenses

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Accrued Expenses

6. Accrued Expenses

Accrued expenses consisted of the following:


	December 31,		September 30,
($ in thousands)	2020		2021

Accrued external research, development and manufacturing costs	$	2,615	$	2,685
Accrued employee compensation and benefits		1,009		4,025
Accrued professional fees		968		2,712
Total	$	4,592	$	9,422

4. Accrued Expenses

Accrued expenses consisted of the following:


	As of December 31,
($ in thousands)	2019		2020
Accrued external research, development and manufacturing costs	$	3,872	$	2,615
Accrued employee compensation and benefits		1,260		1,009
Accrued professional fees		868		968
Total	$	6,000	$	4,592

Debt

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Debt

Debt

7. Debt

On April 30, 2020, the Company received loan proceeds in the amount of approximately $3.3 million under the Paycheck Protection Program (“PPP”). All or portion of this loan and any accrued interest was eligible to be forgiven after a twenty-four week period as long as the borrower used the loan proceeds for eligible purposes, including payroll, benefits, rent and utilities, and maintains its payroll levels. The amount of the loan forgiven was to be reduced if the borrower terminated employees or reduced salaries during the twenty-four week period. The unforgiven portion of the PPP loan was to be payable over two years at an interest rate of 1%, with a deferral of payments for the first ten months. On May 25, 2021, the PPP loan was forgiven and the Company recognized a gain from loan extinguishment in the amount of $3,284 during the nine months ended September 30, 2021.

In March 2021, the Company entered into a term loan agreement with Silicon Valley Bank and SVB Innovation Credit Fund VIII, L.P., which provides a term loan facility of up to $50.0 million with a maturity date of March 1, 2025, or the Loan Agreement. The Company’s obligations under the Loan Agreement are secured by substantially all of its assets except for its intellectual property. The Loan Agreement contains certain customary covenants, including, but not limited to, those relating to additional indebtedness, liens, asset divestitures, and affiliate transactions. If a minimum liquidity amount is not maintained, 50% of the outstanding principal and interest will become cash collateralized. As of September 30, 2021, the Company was in compliance with all covenants. The Company may use the proceeds of borrowings under the Loan Agreement as working capital and to fund its general business requirements.

The Loan Agreement provides that the term loans will be distributed in tranches. The initial term loan tranche of $20.0 million was drawn in March 2021 and is accounted for net of issuance costs which are being accreted to interest expense over the term of the loan using the effective interest method. As of September 30, 2021, three subsequent $10.0 million term loan tranches were eligible to

be disbursed at the request of the Company during specified draw periods between now and 2023 if certain business development milestones and other specified requirements are met by the dates specified in the Loan Agreement. Borrowings bear interest at the greater of 7.5% or the Wall Street Journal Prime Rate plus 4.25% (7.5% as of September 30, 2021). Interest only payments on the principal amount outstanding are due monthly beginning in the first month after the loan is dispersed. Repayment of principal may begin as soon as April 1, 2022 under the level of borrowing outstanding at September 30, 2021, and no later than April 1, 2024. The term loans may only be prepaid in full, and such prepayment requires 30 days’ advance notice and is subject to a prepayment fee of 3.00% (with a step down to 2.00% after March 30, 2022, and a further step down to 1.00% after March 30, 2023). The Company is not obligated to pay a prepayment fee if the Company makes a prepayment after March 30, 2024.

On October 13, 2021, the Company borrowed an additional $10.0 million under the Loan Agreement. As a result of the additional borrowing, the commencement of repayment of principal was deferred to no earlier than July 2023.

In connection with the Loan Agreement, the Company granted warrants to the lenders to purchase shares of common stock at an exercise price of $10.28 per share, of which 287,704 warrants were immediately exercisable. The warrants are classified within stockholders’ equity as the settlement of the warrants is indexed to the Company’s own stock. The Company recognized the fair value of the warrants immediately exercisable within stockholders’ equity using a Black-Scholes valuation model at issuance. As of September 30, 2021, the fair value of warrants ($2.4 million), a 5% final payment fee ($1.0 million) and debt issuance costs ($0.3 million) are being accreted to interest expense over the term of the loan using the effective interest method.

At issuance, the Company initially determined that the funding of an additional tranche was not probable, and therefore no value was ascribed to the remaining 123,302 warrants that were only exercisable upon the funding of the additional tranche. As a result of the Company’s additional $10.0 million borrowings under the Loan Agreement on October 13, 2021, the warrants to purchase the additional 123,302 shares of the Company’s common stock became exercisable at an exercise price of $10.28 per share.

SVB loan payable and net discount or premium balances are as follows:


	September 30,
($ in thousands)	2021
Principal amount of SVB loan payable	$	20,000
Final payment amount of SVB loan payable		1,000
Net premium associated with accretion of final payment and other debt issuance costs		(3,073)
SVB loan payable, current and noncurrent		17,927
Less SVB loan payable, current portion		(3,889)
SVB loan payable, noncurrent portion	$	14,038

Future minimum payments of principal on the Company’s outstanding variable rate borrowings as of September 30, 2021 are as follows:


Year ending December 31:	($ in thousands)
2021 (remainder)	$	—
2022		5,555
2023		6,667
2024		6,667
2025		1,111
Total future payments		20,000

5. Debt

On April 30, 2020, the Company received loan proceeds in the amount of approximately $3.3 million under the Paycheck Protection Program (“PPP”). The PPP, established as part of the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”), provides for loans to qualifying businesses for amounts up to 2.5 times of the average monthly payroll expenses of the qualifying business. All or portion of this loan and any accrued interest may be forgiven after a twenty four week period as long as the borrower uses the loan proceeds for eligible purposes, including payroll, benefits, rent and utilities, and maintains its payroll levels. The amount of the loan forgiven will be reduced if the borrower terminates employees or reduces salaries during the twenty four week period. The unforgiven portion of the PPP loan is payable over two years at an interest rate of 1%, with a deferral of payments for the first ten months.

In September 2020, the Company applied for forgiveness of the outstanding amount under its PPP loan. The Company used the proceeds for purposes it believes were consistent with the requirements of the PPP. The Company determined that loan forgiveness would become probable upon approval by the Small Business Administration of the Company’s forgiveness application. If and when the loan forgiveness becomes probable, the Company will recognize income for debt extinguishment on our statements of operations and comprehensive loss.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Redeemable Convertible Preferred Stock

Leases

12 Months Ended

Dec. 31, 2020

Leases

Leases

6. Leases

The Company’s finance lease relates to its headquarters, which was substantially completed in June 2018 and leased through May 2033, and its operating lease relates to the land lease associated with its headquarters. Historically the Company’s operating leases included a lease for laboratory and office space in Ohio. In March 2020, the Company terminated this lease, effective September 30, 2020, and paid termination fees of less than $0.1 million.

At December 31, 2019 and 2020, the Company had finance lease liabilities of $26.3 million and $24.8 million, respectively, and right-of-use assets of $25.6 million and $23.5 million, respectively, and operating lease liabilities of $0.9 million and $0.8 million, respectively, and right-of-use assets of $0.9 million and $0.8 million, respectively, all of which were included in the balance sheet.

The Company’s leases do not require any contingent rental payments, impose any financial restrictions, or contain any residual value guarantees. Certain of the Company’s leases include renewal options and escalation clauses;

renewal options have been included in the calculation of the lease liabilities and right of use assets as the Company is reasonably certain to exercise the options due to the specialized nature of the leased building. Variable expenses generally represent the Company’s share of the landlord’s operating expenses. The Company does not act as a lessor in any lease arrangements.

The following summarizes quantitative information about the Company’s leases:


	Year Ended
	December 31,
($in thousands)	2019		2020
Finance lease cost
Amortization of right-of-use assets	$	2,060	$	2,060
Interest on lease liabilities		2,298		2,180
Total finance lease cost		4,358		4,240
Operating lease cost		137		152
Total lease cost	$	4,495	$	4,392


	Year Ended						Year Ended
	December 31, 2019						December 31, 2020
	Finance			Operating			Finance			Operating
($ in thousands)	Leases			Leases			Leases			Leases
Operating cash flows from leases	$	(2,298)		$	(137)		$	(2,180)		$	(182)
Financing cash flows from leases	$	(1,292)		$	—		$	(1,500)		$	—
Weighted-average remaining lease term		6.02			6.38			5.52			6.24
Weighted-average discount rate		8.50	%		8.50	%		8.50	%		8.50	%

As of December 31, 2020, the maturities of the Company’s lease liabilities were as follows:


($ in thousands)	Finance Leases		Operating Leases
Year Ended December 31, 2021	$	3,773	$	105
Year Ended December 31, 2022		3,868		105
Year Ended December 31, 2023		3,965		105
Year Ended December 31, 2024		4,065		106
Year Ended December 31, 2025		4,167		106
Thereafter		16,937		678
Total		36,775		1,205
Less: present value discount		(11,956)		(436)
Lease liabilities	$	24,819	$	769

Redeemable Convertible Preferred Stock

12 Months Ended

Dec. 31, 2020

Redeemable Convertible Preferred Stock

7. Redeemable Convertible Preferred Stock

Redeemable Convertible Preferred Stock and Preferred Stock Terms

The Company has outstanding series A redeemable convertible preferred stock, series B redeemable convertible preferred stock, series C redeemable convertible preferred stock and series D redeemable convertible preferred stock, which are collectively referred to as “redeemable convertible preferred stock.” The series A redeemable convertible preferred stock, series B redeemable convertible preferred stock and series C redeemable convertible preferred stock are individually and collectively referred to as “junior” series of preferred stock.

As of December 31, 2019 and December 31, 2020, redeemable convertible preferred stock consisted of the following (in thousands, except share amounts):


	Redeemable	Redeemable
	Convertible	Convertible
	Preferred	Preferred Stock
	Stock	Issued and		Carrying	Liquidation		Issuance
	Authorized	Outstanding	Value		Preference		Price
Series A redeemable convertible preferred stock	18,421,897	18,421,897	$	74,079	$	74,079	$	4.0212
Series B redeemable convertible preferred stock	24,137,647	24,137,647		127,358		136,500	$	5.6550
Series C redeemable convertible preferred stock	11,241,286	11,241,283		70,704		75,000	$	6.6717
Series D redeemable convertible preferred stock	15,812,735	15,812,735		148,848		150,000	$	9.4859
	69,613,565	69,613,562	$	420,989	$	435,579

In connection with the series D redeemable convertible preferred stock financing, the Company granted Fresenius Medical Care the right to purchase up to an aggregate of $30.0 million of its common stock in a private placement effected concurrently with its initial public offering at a price per share equal to the initial public offering price. See Note 13: Related Party Transactions for further discussion of the Company’s relationship with Fresenius Medical Care.

Election of Directors

The holders of the series A redeemable convertible preferred stock and the series B redeemable convertible preferred stock may designate one individual and two individuals, respectively, to the Board of Directors. The holders of the series C redeemable convertible preferred stock may designate one individual to the Board of Directors and Fresenius Medical Care may designate one representative to attend, in a non-voting observer capacity, all meetings of the Company’s Board of Directors.

Conversion to Common Stock

Each share of redeemable convertible preferred stock is convertible, at the option of the holder thereof, into that number of the fully paid and nonassessable shares of common stock determined by dividing the original issue price for the relevant shares by the conversion price. Each share of redeemable convertible preferred stock will automatically be converted into that number of fully-paid, nonassessable shares of common stock at the then effective conversion rate for such shares (i) immediately prior to the closing of a firm commitment underwritten public offering on the New York Stock Exchange or a Nasdaq market pursuant to an effective registration statement filed under the Securities Act of 1933, as amended, if the offering price is not less than $2.7401 per share (as adjusted for any stock dividend, stock split, combination of shares, reorganization, recapitalization, reclassification or other similar event) and the aggregate gross proceeds to the Company are not less than $100.0 million (before deduction of commissions and expenses), (ii) with respect to the series C redeemable convertible preferred stock, series B redeemable convertible preferred stock and series A redeemable convertible preferred stock, upon the receipt by the Company of a written request for such conversion from the holders of at least 60% of such series of redeemable convertible preferred stock then outstanding and at least 60% of the then outstanding shares of series C redeemable convertible preferred stock or (iii) with respect to the series D redeemable convertible preferred stock, upon the receipt by the Company of a written request for such conversion from the holders of a majority of the then outstanding shares of series D redeemable convertible preferred stock.

7. Redeemable Convertible Preferred Stock (continued)

The following are the conversion prices for each series of the redeemable convertible preferred stock as of December 31, 2020:


Series	Conversion Price
Series A redeemable convertible preferred stock	$	4.0212
Series B redeemable convertible preferred stock	$	5.6550
Series C redeemable convertible preferred stock	$	6.6717
Series D redeemable convertible preferred stock	$	9.4859

These conversion prices are subject to adjustment from time to time including for certain share issuances made without consideration or for consideration less than the then applicable conversion price of a series of redeemable convertible preferred stock, dividends, stock splits, and combinations. As of December 31, 2020, each series of redeemable convertible preferred stock is convertible on a one-for-one basis.

The series A, series B, series C and series D redeemable convertible preferred stock includes an anti-dilution feature that adjusts the conversion price, in certain scenarios, if the Company sells shares at a price below the stated conversion price. The anti-dilution provision is considered a contingent beneficial conversion feature. Due to the inability of the Company to determine the price of the shares sold, the Company is unable to determine the number of shares that the holder would receive if the contingency occurs. Therefore, the beneficial conversion feature is not recognized until the contingent event occurs.

Dividends

Any dividends on the redeemable convertible preferred stock are not cumulative. The holders of the redeemable convertible preferred stock are entitled to receive dividends pro rata with the holders of common stock on an as-converted basis, when and if declared and paid by the Board of Directors, out of any assets at the time legally available. Any declared and unpaid dividends on the redeemable convertible preferred stock are payable upon certain voluntary or involuntary acquisition or sale transactions or the liquidation, dissolution or winding up of the Company as described below under “Liquidation,” and no dividends may be made with respect to the common stock unless all dividends declared on the redeemable convertible preferred stock have been paid or set aside for payment.

7. Redeemable Convertible Preferred Stock (continued)

Liquidation

In the event of certain voluntary or involuntary acquisition or sale transactions or upon the liquidation, dissolution or winding up of the Company, each, a Reorganization, in which the holders of the series D redeemable convertible preferred stock receive less than $9.4859 per share plus any declared but unpaid dividends, referred to as the Series D Liquidation Preference, or such lesser amount approved in writing by the holders of a majority of the then outstanding series D redeemable convertible preferred stock, the series D stockholders will receive the series D liquidation preference before the holders of the series C, series B, series A redeemable convertible preferred stock or common stockholders would receive any proceeds relating to such Reorganization, and the entire assets of the Company available for distribution would be distributed pro rata among holders of the series D redeemable convertible preferred stock. In the event that, after the payment to the holders of the series D redeemable convertible preferred stock, the holders of the series C redeemable convertible preferred stock would receive less than $6.6717 per share plus any declared but unpaid dividends or such lesser amount approved by the holders of at least 80% of the then outstanding series C redeemable convertible preferred stock, the entire remaining assets of the Company available for distribution would be distributed pro rata among holders of the series C redeemable convertible preferred stock. In the event that, after the payment to the holders of the series D redeemable convertible preferred stock and series C redeemable convertible preferred stock, the holders of the series B redeemable convertible preferred stock would receive less than $5.6550 per share plus any declared but unpaid dividends or such lesser amount approved by the holders of a majority of the then outstanding series B redeemable convertible preferred stock, the entire remaining assets of the Company available for distribution would be distributed pro rata among holders of the series B redeemable convertible preferred stock. However, in the event of any Reorganization, if the holders of the series D redeemable convertible preferred stock, series C redeemable convertible preferred stock or series B redeemable convertible preferred stock would receive less than 1.25 times their respective liquidation preference per share, the holders of each such series will be entitled to receive, in preference to any distribution of assets to the holders of any junior series, an amount per share equal to 1.25 times such liquidation preference.

In the event that, after the payment to the holders of the series D redeemable convertible preferred stock, series C redeemable convertible preferred stock and series B redeemable convertible preferred stock described above, the holders of the series A redeemable convertible preferred stock would receive less than $4.0212 per share plus any declared but unpaid dividends or such lesser amount approved by the holders of a majority of the then outstanding series A redeemable convertible preferred stock, the entire remaining assets of the Company available for distribution would be distributed pro rata among holders of the series A redeemable convertible preferred stock. After payment to the holders of preferred stock, the remaining assets of the Company available for distribution would be distributed pro rata among the holders of preferred stock and common stock with the preferred stock being treated as if they had been converted to common stock at the then applicable conversion rate.

Voting

Except as provided in the Company’s certificate of incorporation and as required by law, the holders of the redeemable convertible preferred stock vote with the holders of common stock on an as-converted basis. Preferred stockholders will generally vote together with the holders of common stock as a single class but also have class vote approval rights as provided by law and others as specified in the Company’s certificate of incorporation.

7. Redeemable Convertible Preferred Stock (continued)

Redemption and Balance Sheet Classification

In accordance with the Company’s accounting policy, the series A, series B, series C and series D redeemable convertible preferred stock was classified as temporary equity due to the fact that liquidation is not solely within the control of the Company. As of December 31, 2020, liquidation of the series A, series B, series C and series D redeemable convertible preferred stock was not probable because the change in control events (acquisition, sale or asset transfer) that would lead to liquidation are contingent upon events that have not yet occurred and are not considered probable at this time. The Company has not adjusted the carrying value of the redeemable convertible preferred stock to its liquidation preference because a deemed liquidation event obligating the Company to pay the liquidation preference to holders of shares of redeemable convertible preferred stock is not probable of occurring. Subsequent adjustments of the carrying values to the liquidation preference will be made only when it becomes probable that such a deemed liquidation event will occur.

Stockholders, Equity (Deficit)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit)

8. Stockholders’ Equity (Deficit)

Redeemable Convertible Preferred Stock

As of December 31, 2020 and immediately prior to the Merger, Legacy Humacyte had outstanding series A redeemable convertible preferred stock, series B redeemable convertible preferred stock, series C redeemable convertible preferred stock and series D redeemable convertible preferred stock, which are collectively referred to as “redeemable convertible preferred stock.”

In connection with the Merger, all previously issued and outstanding redeemable convertible preferred stock was converted into an equivalent number of shares of common stock of the Company on a one-to-one basis, then multiplied by the Exchange Ratio pursuant to the Merger Agreement.

Common Stock

On August 26, 2021, the Merger and related PIPE Financing was consummated and the Company issued 27,346,449 shares of common stock for proceeds of $242.4 million. The Company incurred $3.9 million of transaction costs, consisting of banking, legal, and other professional fees. Legacy Humacyte assumed $15.2 million of liabilities, including PIPE Financing fees and legal fees, and $0.1 million of assets from AHAC. Immediately following the Merger, there were 103,003,384 shares of common stock outstanding with a par value of $0.0001.

As of September 30, 2021, the Company’s Second Amended and Restated Certificate of Incorporation authorized the Company to issue 250,000,000 shares of common stock at a par value of $0.0001 per share. The number of authorized shares of common stock may be increased or decreased (but not below the number of shares thereof then outstanding or reserved for issuance) by the affirmative vote of the holders of a majority of the capital stock of the Company entitled to vote and without a separate class vote of the common stock.

The holders of common stock are entitled to receive dividends from time to time as may be declared by the Company’s board of directors. Through September 30, 2021, no dividends have been declared.

The holders of common stock are entitled to one vote for each share held with respect to all matters voted on by the common stockholders of the Company.

In the event of a reorganization of the Company, after payment to the preferred stockholders of their liquidation preferences, holders of common stock are entitled to share ratably in all remaining assets of the Company.

As of September 30, 2021, the Company had reserved common stock for future issuances as follows:


		September 30,
		2021
Common stock reserved for Contingent Consideration Shares		15,000,000
Exercise of options under stock plans		6,399,888
Issuance of options under stock plans		7,730,503
Shares available for grant under ESPP		1,030,033
Warrants to purchase common stock		5,465,204
		35,625,628

On August 26, 2021, upon the Closing, all of the outstanding redeemable convertible preferred stock was converted to Common Stock pursuant to the conversion rate effective immediately prior to the Merger and the Exchange Ratio and the remaining amount was reclassified to additional paid-in capital.

Preferred Stock

The Company’s Second Amended and Restated Certificate of Incorporation provides the Company’s board of directors with the authority to issue $0.0001 par value preferred stock in one more series and to establish from time to time the number of shares to be included in each such series, by adopting a resolution and filing a certification of designations. Voting powers, designations, powers, preferences and relative, participating, optional, special and other rights shall be stated and expressed in such resolutions. There were 20,000,000 shares designated as preferred stock and none were outstanding as of September 30, 2021.

Warrants

Activity of warrants for the nine months ended September 30, 2021 is set forth below:


	Legacy
	Humacyte
	Common Stock	Private Placement		Total Common
	Warrants	Warrants	Public Warrants	Stock Warrants

Outstanding as of December 31, 2020	32,961	—	—	32,961
Common Stock Warrants issued to SVB	287,704	—	—	287,704
Common Stock Warrants as Part of the Merger	—	177,500	5,000,000	5,177,500
Warrants Exercised	(32,961)	—	—	(32,961)
Oustanding as of September 30, 2021	287,704	177,500	5,000,000	5,465,204

In conjunction with a long-term debt agreement entered into on March 15, 2006 and paid in full during 2011, the Company issued a warrant that gave the holder the right to purchase 32,961 shares of the Company’s common stock at an exercise price of $1.14 per share, which was outstanding as of December 31, 2020. The warrant was fully exercised on March 4, 2021. There was no activity for the warrant during the year ended December 31, 2020.

See Note 7 — Debt for a discussion of warrants issued in conjunction with the Company’s Loan Agreement.

Private Placement Warrants

The Private Placement Warrants were initially recognized as a liability on the Closing Date, at a fair value of $0.6 million, and the Private Placement Warrant liability was remeasured to fair value as of September 30, 2021, resulting in a loss of less than $0.1 million for the three and nine months ended September 30, 2021, classified within change in fair value of common stock warrant liabilities in the condensed consolidated statements of operations and comprehensive loss.

The Private Placement Warrants were valued using the following assumptions under the Monte Carlo simulation value model:


	August 26,			September 30,
	2021			2021
Market price of public stock	$	10.96		$	11.61
Exercise price	$	11.50		$	11.50
Expected term (years)		5.00			4.91
Expected share price volatility		32.5	%		28.5	%
Risk-free interest rate		0.68	%		0.96	%
Estimated dividend yield		0	%		0	%

Public Warrants

The Public Warrants may only be exercised for a whole number of shares and will expire five years after the completion of the Merger. The Public Warrants became exercisable 30 days after the completion of the Merger.

The Public Warrants were initially recognized as equity on the Closing Date at a fair value of $2.80 per share. There were no exercises of the Public Warrants during the three months ended September 30, 2021.

Contingent Earnout Liability

Following the Closing, former holders of Legacy Humacyte common and preferred shares may receive up to 15,000,000 additional shares of the Company’s common stock in the aggregate, in two equal tranches of 7,500,000 shares of common stock per tranche. The first and second tranches are issuable if the closing volume weighted average price (“VWAP”) per share of common

stock quoted on the Nasdaq (or the exchange on which the shares of common stock are then listed) is greater or equal to $15.00 and $20.00, respectively, over any twenty trading days within any thirty-day trading period.

Upon the Closing, the contingent obligation to issue Contingent Earnout Shares was accounted for as a liability because the triggering events that determine the number of Contingent Earnout Shares required to be issued include events that are not solely indexed to the common stock of Humacyte. The estimated fair value of the total Contingent Earnout Shares at the Closing on August 26, 2021, was $159.4 million based on a Monte Carlo simulation valuation model using a distribution of potential outcomes on a monthly basis over a ten-year period using the most reliable information available. The Contingent Earnout Liability was remeasured to fair value as of September 30, 2021, resulting in the recording of a non-cash loss of $9.8 million for the three and nine months ended September 30, 2021, classified within change in fair value of contingent earnout liability in the condensed consolidated statements of operations and comprehensive loss.

Assumptions used in the valuations are described below:


	August 26,			September 30,
	2021			2021
Current stock price	$	10.96		$	11.61
Expected share price volatility		79.6	%		78.9	%
Risk-free interest rate		1.34	%		1.55	%
Estimated dividend yield		0	%		0.0	%
Expected term (years)		10.00			10.00

8. Stockholders’ Deficit

Common Stock

As of December 31, 2019 and 2020, the Company’s certificate of incorporation, as amended, authorized the Company to issue 340,216,780 shares of common stock, respectively, at a par value of $0.0001 per share. The number of authorized shares of common stock may be increased or decreased (but not below the number of shares thereof then outstanding or reserved for issuance) by the affirmative vote of the holders of a majority (assuming the conversion of all redeemable convertible preferred stock into shares of the Company’s common stock) of the capital stock of the Company entitled to vote and without a separate class vote of the common stock.

The holders of common stock are entitled to receive dividends from time to time as may be declared by the Board of Directors. No cash dividend may be declared or paid to common stockholders until paid on each series of outstanding redeemable convertible preferred stock in accordance with its terms. Through December 31, 2020, no dividends have been declared.

The holders of common stock are entitled to one vote for each share held with respect to all matters voted on by the common stockholders of the Company. Preferred stockholders generally vote together with the holders of common stock as a single class but also have class vote approval rights as provided by law and others as specified in the Company’s certificate of incorporation.

In the event of a Reorganization of the Company, after payment to the preferred stockholders of their liquidation preferences, holders of common stock are entitled, together with holders of redeemable convertible preferred stock, to share ratably in all remaining assets of the Company.

8. Stockholders’ Deficit (continued)

At December 31, 2019 and 2020, the Company had reserved common stock for future issuances as follows:


	December 31,
	2019	2020

Conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Conversion of Series C redeemable convertible preferred stock	11,241,286	11,241,286
Conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Exercise of options under stock plan	5,220,236	4,813,262
Issuance of options under stock plan	2,736,954	2,948,598
Warrant to purchase common stock	32,961	32,961
	77,603,716	77,408,386

Warrant

In conjunction with a long-term debt agreement entered into on March 15, 2006 and paid in full during 2011, the Company issued a warrant that gave the holder the right to purchase 32,961 shares of the Company’s common stock at an exercise price of $1.14 per share, which was outstanding as of December 31, 2019 and 2020. The warrant is exercisable and expires on March 15, 2021. There was no activity for the warrant during the years ended December 31, 2019 and 2020.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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Stock-based Compensation

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Stock-based Compensation

9. Stock-based Compensation

At Closing, the 2021 Long-Term Incentive Plan, or the 2021 Plan, and the 2021 Employee Stock Purchase Plan, or the ESPP, became effective. As of September 30, 2021, 7,730,503 and 1,030,033 shares of common stock were available under the 2021 Plan and ESPP, respectively. On January 1 of each year commencing January 1, 2022, the 2021 Plan and the ESPP reserve will automatically increase in an amount equal to the lesser of (a) 5% and 1%, respectively, of the number of shares of the Company’s common stock outstanding on December 31 of the preceding year and (b) a number of shares of common stock determined by the Company’s board of directors.

Under the 2021 Plan, the Company can grant non-statutory stock options, or NSOs, incentive stock options, or ISOs, stock appreciation rights, restricted stock, restricted stock units, unrestricted stock, performance awards and other forms of awards. Under the ESPP, eligible employees are permitted to purchase shares of the Company’s common stock at the lower of 85% of the closing trading price per share of the Company’s common stock on the first day of the offering or 85% of the closing trading price per share on the exercise date, which will occur on the last day of each offering.

Prior to the Closing, Legacy Humacyte had two equity incentive plans, the 2015 Omnibus Incentive Plan, as amended, or the 2015 Plan, and the 2005 Stock Option Plan, or the 2005 Plan. As a result of the Merger, no further awards may be granted under either the 2015 plan or the 2005 Plan. All awards previously granted and outstanding as of the effective date of the Merger, which total 5,886,706 and 518,432 shares of common stock reserved for options issued under the 2015 Plan and 2005 Plan, respectively, were adjusted to reflect the impact of the Merger as set forth in the Merger Agreement, but otherwise remain in effect pursuant to their original terms. The shares underlying any award granted under the 2015 Plan that are forfeited, cancelled or reacquired by the Company prior to vesting, that expire or that are paid out in cash rather than shares will become available for grant and issuance under the 2021 Plan.

The Company’s stock option plans allow for the grant of awards that the Company believes aid in aligning the interests of these persons with those of its stockholders. The Company’s board of directors determines the specific terms of equity incentive grants, including the exercise price per share and vesting period for option awards. Option awards are granted with an exercise price equal to the fair market value of the Company’s common stock at the date of grant.

The Company has granted options that include either a service-based or performance-based vesting conditions, or both, and a 10-year contractual term. The service-based vesting condition for the plans is generally satisfied over 36 to 48 months from the date of grant. The performance-based vesting conditions are satisfied upon the attainment of certain product development milestones. The

Company recognizes stock-based compensation expense based on the grant date fair value of the awards measured using the Black-Scholes option pricing model. Compensation expense related to awards with service-based vesting conditions is recognized on a straight-line basis over the requisite service period. Option valuation models, including the Black-Scholes option-pricing model, require the input of highly subjective assumptions, and changes in the assumptions used can materially affect the grant-date fair value of an award. These assumptions include the risk-free rate of interest, expected dividend yield, expected volatility, the expected term of the award, and the fair value of the underlying common stock on the date of grant. Forfeitures are accounted for as they occur.

Compensation expense related to awards with performance-based vesting conditions is recognized over the requisite service period using the accelerated attribution method to the extent achievement of the performance-based condition is probable. The Company does not recognize compensation expense related to awards with performance-based vesting conditions until it is probable that the performance-based vesting condition will be achieved. Forfeitures are accounted for as they occur.

Option awards under the Company’s option plans generally provide for accelerated vesting of the unvested portions of any option award in the event of an involuntary termination, as such term is defined in the relevant stock option agreement, of a grantee’s employment during the period that commences 30 days prior to the effective date of a corporate transaction and that ends 12 months following the effective date of such transaction. Additionally, the Company’s board of directors may, in its sole discretion, accelerate the vesting of any unvested stock options in the event of a corporate transaction.

Under the terms of her employment agreement, the Company awarded the Company’s President and Chief Executive Officer, Laura Niklason M.D., PhD., a stock option award in January 2021 entitling her to purchase 1,312,984 shares of the Company’s common stock at an exercise price of $10.28 per share, none of which have vested as of September 30, 2021. This stock option vests in equal annual installments on each of the first three anniversaries of November 9, 2020, subject to acceleration upon a corporate transaction (as defined in the 2015 Plan). The vesting of this award did not accelerate upon finalization of the Merger.

The Company estimated the fair value of the stock options on the date of grant using the following assumptions in the Black-Scholes option-pricing model:


	Three Months Ended September 30,			Nine Months Ended September 30,
	2020		2021⁽¹⁾	2020		2021
Estimated dividend yield	0	%	—	0	%	0	%
Expected share price volatility (weighted average and range, if applicable)	91.6	%	—	91.4% (89.4% to 91.6%)		91.4% (91.0% to 92.1%)
Risk-free interest rate (weighted average and range, if applicable)	0.34	%	—	0.40% (0.34% to 0.75%)		0.68% (0.62% to 1.02%)
Expected term of options (in years)	6.0		—	6.0		6.0

(1)	The Company did not grant any stock options during the three months ended September 30, 2021.

●

Fair Value of Common Stock. As the Company’s common stock was not publicly traded prior to the Merger, the fair value of the shares of its common stock underlying the options has historically been determined by the Company’s board of directors with input from management, after considering independent third-party valuation reports.

●

Expected Term. The expected term represents the period that stock options are expected to be outstanding. The Company calculated the expected term using the simplified method for options, which is available where there is insufficient historical data about exercise patterns and post-vesting employment termination behavior. The simplified method is based on the vesting period and the contractual term for each grant, or for each vesting-tranche for awards with graded vesting. The mid-point between the vesting date and the maximum contractual expiration date is used as the expected term under this method. For awards with multiple vesting-tranches, the times from grant until the mid-points for each of the tranches may be averaged to provide an overall expected term.

●

to use the volatility of its common stock. For purposes of identifying these peer companies, the Company considered the industry, stage of development, size and financial leverage of potential comparable companies.

●

Risk-Free Interest Rate. The risk-free interest rate was based on the yields of U.S. Treasury zero-coupon securities with maturities similar in duration to the expected term of the options.

●

Expected Dividend Yield. The Company has not paid dividends on its common stock nor does it expect to pay dividends in the foreseeable future. Accordingly, the Company has estimated the dividend yield to be zero.

At September 30, 2021, there were 7,730,503 options remaining available for grant under the 2021 Plan. The Company has sufficient authorized and unissued shares to make all issuances currently available under the 2021 Plan.

The following tables show a summary of stock-based compensation expense included in the condensed consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2021, and the three and nine months ended September 30, 2020, and remaining unrecognized cost as of September 30, 2021 and 2020:


	Three Months Ended September 30,				Nine Months Ended September 30,
($ in thousands)	2020		2021		2020		2021
Research and development	$	308	$	486	$	781	$	1,837
General and administrative		862		1,391		2,685		5,498
Total	$	1,170	$	1,877	$	3,466	$	7,335


	December 31,		September 30,
($ in thousands)	2020		2021
Unrecognized share-based compensation cost	$	5,789	$	12,480
Expected weighted average period compensation costs to be recognized (years)		1.7		2.1

A summary of option activity under the Company’s stock option plans during the nine months ended September 30, 2021 is presented below:


				Weighted
				Average
		Weighted		Remaining	Aggregate
		Average Exercise		Contractual Term	Intrinsic Value
	Number of Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Granted	1,838,029	$	10.28
Exercised	(188,006)	$	2.97
Forfeited	(63,397)	$	7.87
Options outstanding at September 30, 2021	6,399,888	$	7.33	6.6	$	26,705
Vested and exercisable, September 30, 2021	4,092,342	$	5.74	5.1	$	23,345
Vested and expected to vest, September 30, 2021	6,399,888	$	7.33	6.6	$	26,705

The Company did not grant any stock options during the three months ended September 30, 2021.

9. Stock-based Compensation

The Company has adopted the 2015 Omnibus Incentive Plan, as amended, or the 2015 Plan, which allows for the grant of nonstatutory stock options, or NSOs, and incentive stock options, or ISOs, stock appreciation rights, restricted stock, restricted stock units and unrestricted stock awards to employees, officers, directors, and consultants in the service of the Company. The Company believes that such awards aid in aligning the interests of these persons with those of its stockholders. The Board of Directors determines the specific terms of equity incentive grants, including the exercise price per share and vesting period for option awards. Option awards are granted with an exercise price equal to the fair market value of the Company’s common stock at the date of grant.

The Company has granted options that include either a service-based or performance-based vesting condition and a 10-year contractual term. The service-based vesting condition is generally satisfied over 36 months from the date of grant. The performance-based vesting conditions are satisfied upon the attainment of certain product development milestones. The Company recognizes stock-based compensation expense based on the grant date fair value of the awards. Compensation expense related to awards with service-based vesting conditions is recognized on a straight-line basis over the requisite service period. Compensation expense related to awards with performance-based vesting conditions is recognized over the requisite service period using the accelerated attribution method to the extent achievement of the performance-based condition is probable. The Company does not recognize compensation expense related to awards with performance-based vesting conditions until it is probable that the performance-based vesting condition will be achieved. Forfeitures are accounted for as they occur.

Option awards under the 2015 Plan generally provide for accelerated vesting of the unvested portions of any option award in the event of an involuntary termination, as such term is defined in the relevant stock option agreement, of a grantee’s employment during the period that commences 30 days prior to the effective date of a corporate transaction and that ends 12 months following the effective date of such transaction. Additionally, the Company’s board of directors may, in its sole discretion, accelerate the vesting of any unvested stock options in the event of a corporate transaction.

9. Stock-based Compensation (continued)

The Company used the following assumptions on the date of grant to estimate the fair value of the stock options in the Black-Scholes option-pricing model as follows:


	Year Ended December 31,
	2019		2020
Estimated dividend yield	0	%	0	%
Expected share price volatility	70.1%-87.7	%	89.4% - 91.6	%
Risk-free interest rate	1.76% - 2.46	%	0.34% - 0.75	%
Expected term of options (in years)	6.00		6.00

●

Fair Value of Common Stock. As the Company’s common stock has not historically been publicly traded, the fair value of the shares of its common stock underlying the options has historically been determined by the Company’s board of directors with input from management, after considering independent third-party valuation reports.

●

Expected Volatility. The expected volatility was based on the historical share volatility of several publicly traded peer companies over a period of time equal to the expected term of the options, as the Company does not have any trading history to use the volatility of its common stock. For purposes of identifying these peer companies, the Company considered the industry, stage of development, size and financial leverage of potential comparable companies.

●

Risk-Free Interest Rate. The risk-free interest rate was based on the yields of US Treasury zero-coupon securities with maturities similar in duration to the expected term of the options.

●

At December 31, 2020, there were 2,948,598 options remaining available for grant under the 2015 Plan. The Company has sufficient authorized and unissued shares to make all issuances currently contemplated under the 2015 Plan.

9. Stock-based Compensation (continued)

The following tables show a summary of stock-based compensation expense included in the statements of operations and comprehensive loss for the years ended December 31, 2019 and 2020, and remaining unrecognized cost as of December 31, 2019 and 2020:


	Year Ended December 31,
($ in thousands)	2019		2020
Research and development	$	914	$	1,135
General and administrative		3,543		3,559
Total	$	4,457	$	4,694


	As of December 31,
($ in thousands)	2019		2020
Unrecognized share-based compensation cost	$	7,919	$	5,789
Expected weighted average period compensation costs to be recognized (years)		1.8		1.7

A summary of option activity under the 2015 Plan during the years ended December 31, 2019 and 2020 is presented below:


				Weighted
				Average
		Weighted		Remaining	Aggregate
	Number of	Average Exercise		Contractual Term	Intrinsic Value
	Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2018	5,638,773	$	4.69	7.4	$	21,354
Granted	621,031		8.49
Exercised	(620,831)		1.97
Forfeited	(418,737)		7.62
Options outstanding at December 31, 2019	5,220,236	$	5.22	6.5	$	17,044
Granted	480,856		9.79
Exercised	(195,239)		1.55
Forfeited	(692,591)		3.76
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Vested and exercisable, December 31, 2020	3,392,302	$	4.99	5.9	$	17,925
Vested and expected to vest, December 31, 2020	4,813,262	$	6.04	6.6	$	20,422

The total intrinsic value of options exercised during the years ended December 31, 2019 and 2020 was $4.0 million and $1.4 million, respectively.

The weighted-average grant-date fair value per share of options granted during the years ended December 31, 2019 and 2020 was $5.84 and $7.26, respectively.

Income Taxes

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

10. Income Taxes

The Company’s tax provision for interim periods is determined using an estimate of its annual effective tax rate, adjusted for discrete items, if any, that arise during the period. Each quarter, the Company updates its estimate of the annual effective tax rate and, if the estimated annual effective tax rate changes, the Company makes a cumulative adjustment in such period. No adjustment was made as of September 30, 2021. The Company’s effective federal tax rate for the three and nine months ended September 30, 2020 and 2021 was 0%, primarily as a result of estimated tax losses for the fiscal year to date offset by the increase in the valuation allowance in the net operating loss carryforwards.

The Company did not record any income tax expense or benefit during the three and nine months ended September 30, 2020 and 2021. The Company has a net operating loss and has provided a valuation allowance against net deferred tax assets due to uncertainties regarding the Company’s ability to realize these assets. All losses before income taxes arose in the United States.

On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security (“CARES”) Act was passed by the U.S. Congress and signed into United States law. The CARES Act, among other things, includes certain provisions for individuals and corporations; however, these benefits did not materially impact the Company’s income tax provision in the periods presented.

10. Income Taxes

The Company did not record any income tax expense or benefit during the years ended December 31, 2019 and 2020. The Company has a net operating loss and has provided a valuation allowance against net deferred tax assets due to uncertainties regarding the Company’s ability to realize these assets. All losses before income taxes arose in the US.

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s deferred tax assets and deferred tax liabilities, including valuation allowances, are as follows:


	As of December 31,
($ in thousands)	2019		2020
Deferred tax assets:
Net operating loss	$	50,616	$	53,515
Capitalized research and development		19,660		32,337
Research credits		10,658		15,056
Share-based compensation		1,669		2,519
Right of use lease liability		207		177
Accrued expenses		71		57
Other		1		1
Total deferred tax asset		82,882		103,662
Less: valuation allowance		(82,193)		(101,757)
Total net deferred tax asset		689		1,905

Deferred tax liabilities:
Basis difference in fixed assets		(482)		(1,728)
Right of use lease assets		(207)		(177)
Total deferred tax liability		(689)		(1,905)
Total net deferred tax asset/(liability)	$	—	$	—

A valuation allowance is provided for deferred tax assets where the recoverability of the assets is uncertain. The determination to provide a valuation allowance is dependent upon the assessment of whether it is more likely than not that sufficient future taxable income will be generated to utilize the deferred tax assets. Based on the weight of the available evidence, which includes the Company’s historical operating losses, lack of taxable income and the accumulated deficit, the Company provided a full valuation allowance against the deferred tax assets resulting from the tax loss and credits carried forward as of December 31, 2019 and December 31, 2020.

10. Income Taxes (continued)

The reasons for the difference between the actual income tax benefit for the years ended December 31, 2019 and 2020, and the amount computed by applying the statutory Federal income tax rate to losses before income taxes are as follows:


	December 31,
	2019				2020
($ in thousands)	Amount		Rate		Amount		Rate
Income tax benefit at statutory rate	$	(17,939)	21.0	%	$	(13,970)	21.0	%
State income taxes, net of federal benefit		(1,739)	2.0	%		(1,338)	2.0	%
Tax credits		(1,821)	2.1	%		(2,625)	3.9	%
Other nondeductible expenses		54	0.0	%		90	(0.1)	%
Deferred rate changes		16	0.0	%		16	0.0	%
Other		449	(0.5)	%		(1,736)	2.6	%
Change in valuation allowance		20,980	(24.6)	%		19,563	(29.4)	%
Provision for income taxes	$	—	0.0	%	$	—	0.0	%

As of December 31, 2020 the Company had approximately $232.7 million and $232.6 million of Federal and state net operating losses, respectively. Of this amount, $71.5 million of Federal net operating losses are carried over indefinitely, while the remaining amount begins to expire in 2025. The Company’s net operating loss carryforwards are subject to the application of the 80% limitation on taxable income beginning in 2021. Some of these state net operating losses included in these amounts follow the Federal Tax Cuts and Jobs Act and are carried over indefinitely, and others have various expiration dates.

As of December 31, 2019 and December 31, 2020 the Company had Federal and state research tax credit carryforwards of $10.7 million and $15.1 million, respectively. These credit carryforwards begin to expire in 2021.

Net operating loss carryforwards and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service, or IRS, and may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders or groups over a three-year period in excess of 50% as defined under Sections 382 and 383 in the Internal Revenue Code, which could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. The Company has not determined whether there have been any cumulative ownership changes or the impact on the utilization of the loss carryforwards if such changes have occurred.

The Company applies the accounting guidance for uncertainties in income taxes, which prescribes a recognition threshold and measurement process for recording uncertain tax positions taken, or expected to be taken, in a tax return in the financial statements. Additionally, the guidance also prescribes the treatment for derecognition, classification, accounting in interim periods and disclosure requirements for uncertain tax positions. The Company accrues for the estimated amount of taxes for uncertain tax positions if it is more likely than not that the Company would be required to pay such additional taxes.

On March 27, 2020, the CARES Act was passed by the U.S. Congress and signed into United States law. The CARES Act, among other things, includes certain provisions for individuals and corporations (including a suspension on the application of the 80% limitation described above for taxable years beginning prior to January 1, 2021); however, these benefits did not materially impact the Company’s income tax provision in the periods presented.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

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Retirement Plan

12 Months Ended

Dec. 31, 2020

Retirement Plan

Retirement Plan

11. Retirement Plan

The Company maintains two defined contribution employee retirement plans, or 401(k) plans, for all employees upon their date of hire. The 401(k) plans are intended to qualify as tax-qualified plans under Section 401(k) of the Internal Revenue Code of 1986, as amended. The plans permit employees to contribute, on a pre-tax basis, a portion of their salary up to the Federally mandated limits. The Company matches an employee’s contribution up to 4% of the employee’s compensation. Contributions to the plans by the Company totaled $0.6 million for the year ended December 31, 2019,and $0.6 million for the year ended December 31, 2020.

The entire disclosure for retirement benefits.

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Commitments and Contingencies

Commitments and Contingencies

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Commitments and Contingencies

11. Commitments and Contingencies

Patent License Agreements

Duke University

In March 2006, the Company entered into a license agreement with Duke University, or Duke, which was subsequently amended in 2011, 2014, 2015, 2018 and 2019. Under this license agreement, Duke granted the Company a worldwide, exclusive, sublicensable license to certain patents related to decellularized tissue engineering, referred to as the patent rights, as well as a non-exclusive license to use and practice certain know-how related to the patent rights. The relevant licensed patent on decellularization of tissue will expire in 2021. The Company has agreed to use commercially reasonable efforts to develop, register, market and sell products utilizing the patent rights, referred to as the licensed products. Any services provided to a third party utilizing licensed products are referred to as licensed services. The Company has also agreed to meet certain benchmarks in its development efforts, including as to development events, clinical trials, regulatory submissions and marketing approval, within specified timeframes. Under the license agreement, Duke retains the right to use the patent rights for its own educational and research purposes, and to provide the patent rights to other non-profit, governmental or higher-learning institutions for non-commercial purposes without paying royalties or other fees.

In connection with the Company’s entry into the license agreement, the Company granted equity consideration to Duke in the form of 52,693 shares of the Company’s common stock. Under the license agreement, the Company also agreed to pay Duke:

●

a low single-digit percentage royalty on eligible sales of licensed products and licensed services, plus a low double-digit percentage of any sublicensing revenue;

●

an annual minimum royalty beginning in 2012, which increases in the calendar year immediately following the first commercial sale of licensed products or licensed services (whichever occurs first); and

●

an additional amount in license fees, as certain milestones are met.

The license agreement remains effective until the last of the patent rights expires or four years after the Company’s first commercial sale, unless earlier terminated. Either party may terminate the agreement for fraud, willful misconduct or illegal conduct, or uncured material breach. Duke may terminate the agreement if the Company becomes insolvent. Duke may also terminate the license, convert the license into a non-exclusive license or seek assignment of any sublicense if the Company fails to reach diligence milestones within the applicable time period. If the Company abandons any claim, patent or patent application, its rights under the license with respect to such patent rights will be terminated in the territory in which the Company abandons such rights. The Company may terminate the license agreement unilaterally upon three months’ prior notice to Duke. The Company agrees to indemnify Duke against certain third-party claims. Payments to Duke under the license agreement were immaterial during the periods presented.

Yale University

In February 2014, the Company entered into a license agreement with Yale University, or Yale, that granted the Company a worldwide license to the patents related to coatings for small-diameter vessels to inhibit clotting. The license granted under the agreement is exclusive in the field of engineered vascular tissues and tissues and extracellular matrix-based implants used for vascular repair, reconstruction and replacement (provided that all uses are vascular tissues within the range of 1 – 12mm in diameter), except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes. The Company has agreed to pay to Yale an annual maintenance

fee, increasing between the first and fourth anniversaries of the agreement up to a maximum of less than $0.1 million per year for this license.

In August 2019, the Company entered into a license agreement with Yale, that granted the Company a worldwide license to the patents related to Bioartificial Vascular Pancreas (BVP). The license granted under the agreement is exclusive in the field of engineered vascular tissues that deliver pancreatic islet cells to patients, except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes. The Company has agreed to pay to Yale an annual maintenance fee, increasing between the first and fourth anniversaries of the agreement up to a maximum of less than $0.1 million per year for this license.

In August 2019, the Company entered into a license agreement with Yale that granted the Company a worldwide license to the patents related to tubular prostheses. The license granted under the agreement is exclusive in the field of engineered urinary conduits, engineered tracheas/airways, and engineered esophagi, except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes. The Company has agreed to pay to Yale an annual maintenance fee, increasing between the first and fourth anniversaries of the agreement up to a maximum of less than $0.1 million per year for this license.

The Company has agreed to use reasonable commercial efforts to develop and commercialize the licensed patents and any licensed products and methods, and to use reasonable efforts to make the licensed products available to patients in low and low-middle income countries. The Company is also obligated to provide Yale periodically an updated and revised copy of its plan for each license, which must indicate progress of its development and commercialization. The Company may also sublicense the Company’s rights without Yale’s prior written consent, but such sublicense is subject to certain conditions.

In connection with its entry into the license agreement, the Company paid Yale upfront cash fees. The Company has also agreed to pay Yale:

●

annual maintenance fees, increasing between the first anniversary of the agreement until the fifth anniversary for the coating and BVP licenses and until the fourth anniversary for the tubular prostheses license up to a maximum of less than $0.1 million per year;

●

milestone payments upon achievement of certain regulatory and commercial milestones of $0.2 million and $0.6 million;

●

a low single-digit percentage royalty on worldwide net sales, subject to reductions for third-party license fees; and

●

a low double-digit percentage of sublicensing income.

If the Company or any of its future sublicensees bring a patent challenge against Yale or assists another party in bringing a patent challenge against Yale, the license fees described above will be subject to certain increases and penalties.

The agreements expire on a country-by-country basis on the date on which the last of the patents in such country expires, lapses or is declared invalid. Yale may terminate the agreements if the Company fails to (i) provide written diligence reports, (ii) provide commercially reasonable diligence plans, (iii) implement the plans in accordance with the obligations under the agreements, or (iv) reach certain research and development milestones within the scheduled timeframe set forth in the agreements; however, any such termination right would be limited in scope to the country to which such failure relates. Yale may also terminate for the Company’s non-payment, uncured material breach, failure to obtain adequate insurance, bringing or assisting in bringing of a patent challenge against Yale, abandonment of the research and development of the Company’s products or insolvency. The Company may terminate the license agreements (i) on 90 days’ prior written notice to Yale, provided the Company is not in breach of the license agreements and has made all required payments to Yale thereunder and (ii) on written notice to Yale following an uncured material breach. With respect to the license agreements related to small-diameter vessels and BVP, the Company’s rights under the license agreements will also terminate automatically with respect to a patent application or patent within the licensed patents in a specified country if, upon receipt of written notice from Yale, the Company does not agree to pay the patent filing, prosecution and maintenance fees incurred by Yale for such patent applications or patents in the specified country. Under certain circumstances, Yale may, at its option, convert the exclusive licenses to non-exclusive licenses if the Company declines to initiate certain infringement or interference proceedings with

respect to the licensed patents. The Company has agreed to indemnify Yale against certain third-party claims. Payments to Yale under the license agreement were immaterial during the periods presented.

Legal Matters

The Company currently is not aware of any legal proceedings or claims that management believes will have, individually or in the aggregate, a material adverse effect on the Company’s business, financial condition, results of operations, or cash flows.

Indemnification

To the extent permitted under Delaware law, the Company has agreed to indemnify its directors and officers for certain events or occurrences while the director or officer is, or was serving, at the Company’s request in such capacity. The indemnification period covers all pertinent events and occurrences during the director’s or officer’s service. The maximum potential amount of future payments the Company could be required to make under these indemnification arrangements is not specified in such arrangements; however, the Company has director and officer insurance coverage that is intended to reduce its exposure and enable the Company to recover a portion of any potential future amounts the Company could be required to make. To date, the Company has not incurred any costs as a result of such obligations and has not accrued any liabilities related to such obligations in the condensed consolidated financial statements.

12. Commitments and Contingencies

Patent License Agreements

Duke University

●

a low single-digit percentage royalty on eligible sales of licensed products and licensed services, plus a low double-digit percentage of any sublicensing revenue;

●

an additional amount in license fees, as certain milestones are met.

The license agreement remains effective until the last of the patent rights expires or four years after our first commercial sale, unless earlier terminated. Either party may terminate the agreement for fraud, willful misconduct or illegal conduct, or uncured material breach. Duke may terminate the agreement if the Company becomes insolvent. Duke may also terminate the license, convert the license into a non-exclusive license or seek assignment of any sublicense if the Company fails to reach diligence milestones within the applicable time period. If the Company abandons any claim, patent or patent application, its rights under the license with respect to such patent rights will be terminated in the territory in which the Company abandons such rights. The Company may terminate the license agreement unilaterally upon three months’ prior notice to Duke. The Company agrees to indemnify Duke against certain third-party claims. Payments to Duke under the license agreement were immaterial during the periods presented.

12. Commitments and Contingencies (continued)

Yale University

In February 2014, the Company entered into a license agreement with Yale University, or Yale, that granted the Company a worldwide license to the patents related to coatings for small-diameter vessels to inhibit clotting. The license granted under the agreement is exclusive in the field of engineered vascular tissues and tissues and extracellular matrix-based implants used for vascular repair, reconstruction and replacement (provided that all uses are vascular tissues within the range of 1–12mm in diameter), except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes.

In August 2019, the Company entered into a license agreement with Yale, that granted the Company a worldwide license to the patents related to tubular prostheses. The license granted under the agreement is exclusive in the field of engineered urinary conduits, engineered tracheas/airways, and engineered esophagi, except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes.

In connection with its entry into the license agreement, the Company paid Yale upfront cash fees. The Company has also agreed to pay Yale:

●

milestone payments upon achievement of certain regulatory and commercial milestones;

●

a low single-digit percentage royalty on worldwide net sales, subject to reductions for third-party license fees; and

●

a low double-digit percentage of sublicensing income.

12. Commitments and Contingencies (continued)

Legal Matters

Indemnification

To the extent permitted under Delaware law, the Company has agreed to indemnify its directors and officers for certain events or occurrences while the director or officer is, or was serving, at the Company’s request in such capacity. The indemnification period covers all pertinent events and occurrences during the director’s or officer’s service. The maximum potential amount of future payments the Company could be required to make under these indemnification arrangements is not specified in such arrangements; however, the Company has director and officer insurance coverage that is intended to reduce its exposure and enable the Company to recover a portion of any future amounts paid. The Company believes the estimated fair value of these indemnification arrangements in excess of applicable insurance coverage is immaterial.

Related Party Transactions

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Related Party Transactions

12. Related Party Transactions

Fresenius Medical Care investments and distribution agreement

In June 2018, the Company completed a $150 million financing transaction pursuant to which Fresenius Medical Care purchased shares of series D redeemable convertible preferred stock that at the Closing of the Merger converted into 15,812,735 shares of the Company’s common stock. In August 2021, Fresenius Medical Care invested $25 million as part of the PIPE Financing and received 2.5 million shares of the Company’s common stock.

In addition, the Company entered into a distribution agreement with Fresenius Medical Care in June 2018 which, as amended as of February 16, 2021, granted Fresenius Medical Care and its affiliates exclusive rights to develop outside the United States and EU and commercialize outside of the United States the Company’s 6 millimeter x 42cm HAV and all improvements thereto, and modifications and derivatives thereof (including any changes to the length, diameter or configuration of the foregoing), for use in vascular creation, repair, replacement or construction, including renal replacement therapy for dialysis access, the treatment of peripheral arterial disease, and the treatment of vascular trauma, but excluding coronary artery bypass graft, pediatric heart surgery, or adhering pancreatic islet cells onto the outer surface of the distribution product for use in diabetic patients. Within the United States, Fresenius Medical Care will collaborate with the Company in its commercialization of the product in the field, including adoption of the distribution product as a standard of care in patients for which such use is supported by clinical results and health economic analyses.

The Company is responsible for developing and seeking regulatory approval for the distribution product in the field in the United States. For countries outside the United States, the parties agreed to use commercially reasonable efforts to satisfy certain agreed minimum market entry criteria for the distribution product in the field in such country. For the EU, once such criteria have been satisfied for the applicable country, or if the parties otherwise mutually agree to obtain regulatory approval for the distribution product in the field in the applicable country, the Company agreed to use commercially reasonable efforts to obtain such regulatory approval (other than pricing approval), and Fresenius Medical Care agreed to use commercially reasonable efforts to obtain the corresponding pricing approval. For the rest of the world (i.e., outside the United States and the EU), once such criteria have been satisfied for the applicable country, or if the parties otherwise mutually agree to obtain regulatory and pricing approval for the distribution product in the field in the applicable country, Fresenius Medical Care agreed to use commercially reasonable efforts to obtain such approvals, and the Company agreed to use commercially reasonable efforts to support Fresenius Medical Care in its efforts.

and regulatory materials controlled by the Company during the term to develop the distribution product in accordance with the terms of the distribution agreement. In addition, the Company grants to Fresenius Medical Care, among other things, a perpetual, irrevocable, non-exclusive sublicensable license under the patents and know-how that primarily relate to the distribution product or its manufacture and that were created, conceived or developed solely or jointly by or on behalf of Fresenius Medical Care in the performance of its activities under the distribution agreement.

The distribution agreement provides that the Company will own all know-how and patents that primarily relate to the distribution product or its manufacture that are created, conceived or developed by or on behalf of either party in the performance of activities under the distribution agreement. Ownership of all other know-how, patents, materials and other intellectual property created, conceived or developed during the performance of activities under the distribution agreement will be determined in accordance with U.S. patent laws for determining inventorship.

The Company is obligated to make payments to Fresenius Medical Care based on a share of aggregate net sales by or on behalf of the Company of the distribution product in the United States in the field. Such revenue-share payments will be a percentage of net sales in the low double digits, without regard to the calendar year in which such net sales are attributable, until such time that the Company has paid to Fresenius Medical Care a certain total amount, at which time the revenue-share will decrease to a percentage of net sales in the mid-single digits. The amounts that Fresenius Medical Care will be obligated to pay the Company under the distribution agreement for sales of the distribution product in the field outside of the United States will vary. Fresenius Medical Care agreed to pay the Company initially, on a country-by-country basis for sales outside of the United States, the amount equal to the average cost of manufacturing the Company’s distribution product plus a fixed dollar amount per unit. Following a specified period, on a country-by-country basis outside of the United States, Fresenius Medical Care will pay the Company a fixed percentage of net sales for each unit sold in such country, such that the Company will receive more than half of such net sales.

The distribution agreement will generally continue on a country-by-country basis until the later of (a) the tenth anniversary of the launch date of the distribution product in the relevant country or (b) the expiration of the last-to-expire valid claim of specified patents in such country. Each party is permitted to terminate the distribution agreement for insolvency of, or, under certain circumstances, including various cure periods, material breach by the other party. Subject to a cure period, Fresenius Medical Care may also terminate the distribution agreement in its entirety or on a country-by-country basis (i) for certain withdrawals of regulatory approval or (ii) for termination or expiration of any of our in-licenses that is necessary for the exercise of Fresenius Medical Care’s rights, or the satisfaction of its obligations, under the distribution agreement. In addition, Fresenius Medical Care may terminate the distribution agreement for convenience on a country-by-country basis upon not less than 12 months’ written notice to the Company, although Fresenius Medical Care is not permitted to give such notice prior to the end of the second year following launch of the distribution product in such country. Each party is required to indemnify one another for certain third-party claims.

Arrangements with Dr. Niklason and Yale University

In September 2016, the Company entered into a Memorandum of Understanding Regarding Scientific and Operational Leadership, or MOU, with Dr. Niklason in connection with her performance of various consulting activities for the Company.

The MOU provided for the Company to make a payment each year through 2023 to the academic institution with which Dr. Niklason was then affiliated, up to an aggregate amount of $2.5 million for 2018 through 2023, and to pay Dr. Niklason reasonable consulting fees in consideration of the services she performed for the Company. For the three and nine months ended September 30, 2020, the company made payments under the MOU of $0.1 million and $0.4 million, respectively, to, or on behalf of, Yale University, where Dr. Niklason, currently the Company’s President, CEO and a member of the Company’s board of directors, serves as a Professor Adjunct, Division Chief and Vice Chair, Research in Anesthesia. The MOU was terminated effective November 9, 2020.

The following table shows a summary of related party expenses included in the statements of operations and comprehensive loss for the three and nine months ended September 30, 2020 and 2021:


	Three Months Ended September 30,		Nine Months Ended September 30,
($ in thousands)	2020	2021	2020	2021
Expenses under MOU	125	—	375	—
License expenses	20	—	70	85
Other	4	2	17	83
Total	149	2	462	168

As of December 31, 2020 and September 30, 2021, the Company was a party to license agreements with Yale University, as described in Note 11 — Commitments and Contingencies, above.

13. Related Party Transactions

Fresenius Medical Care distribution agreement

In addition to Fresenius Medical Care’s purchase of series D redeemable convertible preferred stock, the Company entered into a distribution agreement with Fresenius Medical Care in June 2018 which, as amended as of February 16, 2021, granted Fresenius Medical Care and its affiliates exclusive rights to develop outside the United States and EU and commercialize outside of the United States the Company’s 6mm x 42cm HAV and all improvements thereto, and modifications and derivatives thereof (including any changes to the length, diameter or configuration of the foregoing), for use in vascular creation, repair, replacement or construction, including renal replacement therapy for dialysis access, the treatment of peripheral arterial disease, and the treatment of vascular trauma, but excluding coronary artery bypass graft, pediatric heart surgery, or adhering pancreatic islet cells onto the outer surface of the distribution product for use in diabetic patients. Within the United States, Fresenius Medical Care will collaborate with the Company in its commercialization of the product in the field, including adoption of the distribution product as a standard of care in patients for which such use is supported by clinical results and health economic analyses.

Under the distribution agreement, the Company grants an exclusive, sublicensable license to Fresenius Medical Care under the patents, know-how and regulatory materials controlled by the Company during the term to commercialize the distribution product in the field outside the United States, subject to the Company’s retained rights to carry out its obligations under the distribution agreement. The Company also grants a non-exclusive, sublicensable license to Fresenius Medical Care under the patents, know-how and regulatory materials controlled by the Company during the term to develop the distribution product in accordance with the terms of the distribution agreement. In addition, the Company grants to Fresenius Medical Care, among other things, a perpetual, irrevocable, non-exclusive sublicensable license under the patents and know-how that primarily relate to the distribution product or its manufacture and that were created, conceived or developed solely or jointly by or on behalf of Fresenius Medical Care in the performance of its activities under the distribution agreement.

13. Related Party Transactions (continued)

Arrangements with Dr. Niklason and Yale University

The MOU provided for the Company to make a payment each year through 2023 to the academic institution with which Dr. Niklason was then affiliated, up to an aggregate amount of $2.5 million for 2018 through 2023, and to pay Dr. Niklason reasonable consulting fees in consideration of the services she performed for the Company. For the years ended December 31, 2019 and 2020, the company made payments under the MOU of $0.4 million and $0.5 million, respectively, to, or on behalf of, Yale University, where Dr. Niklason, currently the Company’s President, CEO and a member of the Company’s board of directors, serves as a Professor Adjunct, Division Chief and Vice Chair, Research in Anesthesia. The MOU was terminated effective November 9, 2020.

The following table shows a summary of related party expenses included in the statements of operations and comprehensive loss for the years ended December 31, 2019 and 2020:


	Year Ended
	December 31,
($ in thousands)	2019		2020
Expenses under MOU	$	422	$	500
License expenses		110		92
Other		39		28
Total	$	571	$	620

As of December 31, 2019 and December 31, 2020, the Company was a party to license agreements with Yale University, as described in Note 12 — Commitments and Contingencies above.

Subsequent Events

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Subsequent Events [Abstract]

Subsequent Events

13. Subsequent Events

In preparing the condensed consolidated financial statements as of September 30, 2021 and for the three and nine months ended September 30, 2021, the Company evaluated the effect subsequent events would have on the financial statements through the date the financial statements were issued.

On October 13, 2021, the Company borrowed an additional $10.0 million under the Loan Agreement, and the warrants to purchase an additional 123,302 shares of the Company’s common stock at an exercise price of $10.28 per share became exercisable. See Note 7 — Debt and Note 8 — Stockholders’ Equity (Deficit) for additional information.

14. Subsequent Events

The Company evaluated the effect subsequent events would have on the financial statements through March 22, 2021, which is the date the financial statements were issued.

Under the terms of her employment agreement, the Company awarded Dr. Niklason an additional stock option award in January 2021 entitling her to purchase 1,312,984 shares of the Company’s common stock at an exercise price of $10.28 per share, none of which have vested as of the issuance date of these financial statements. This stock option vests in equal annual installments on each of the first three anniversaries of November 9, 2020, subject to acceleration upon a corporate transaction (as defined in the 2015 Plan).

Under the terms of his consulting agreement, the Company awarded Mr. Sander an additional stock option award in January 2021 entitling him to purchase 183,817 shares of the Company’s common stock at an exercise price of $10.28 per share, none of which have vested as of the issuance date of these financial statements. This stock option vests in equal annual installments on each of the first three anniversaries of November 9, 2020, subject to acceleration upon a corporate transaction (as defined in the 2015 Plan).

On February 17, 2021, the Company entered into a business combination agreement with AHAC and Merger Sub, a wholly owned subsidiary of AHAC, pursuant to which Merger Sub will merge with the Company, with the Company surviving the Merger as a wholly owned subsidiary of AHAC. As a result of the Merger, AHAC will immediately be renamed New Humacyte. Immediately prior to the consummation of the Merger, the Company’s outstanding preferred stock will automatically convert into shares of the Company’s common stock at the then-effective conversion ratio. In addition, concurrently with the completion of the Merger, certain investors have agreed to subscribe for and purchase an aggregate of $175 million of common stock of New Humacyte. The boards of directors of both AHAC and the Company have approved the proposed Merger. Completion of the Merger is subject to approval of AHAC’s shareholders and the satisfaction or waiver of certain other customary closing conditions. The Company expects that the Merger will represent a business combination pursuant to FASB ASC Topic 805, Business Combinations and will be accounted for as a reverse recapitalization in accordance with GAAP. Under this method of accounting, AHAC will be treated as the acquired company for financial reporting purposes. This determination is primarily based on the fact that subsequent to the Merger, the Company’s stockholders are expected to have a majority of the voting power of the combined company, the Company will comprise all of the ongoing operations of the Combined Company, the Company will comprise a majority of the governing body of the combined company, and the Company’s senior management will comprise all of the senior management of the combined company. Accordingly, for accounting purposes, the Merger will be treated as the equivalent of the Company issuing shares for the net assets of AHAC, accompanied by a recapitalization. The net assets of AHAC will be stated at historical costs. No goodwill or other intangible assets will be recorded. Operations prior to the Merger will be those of the Company.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Unaudited Interim Condensed Consolidated Financial Statements

Basis of Presentation

Basis of Presentation

Unless otherwise noted, the Company has retroactively adjusted all common and preferred share and related price information to give effect to the Exchange Ratio established in the Merger Agreement.

Basis of Presentation

The Company has prepared the accompanying financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP.

Reverse Recapitalization

Unaudited Interim Condensed Consolidated Financial Statements

On August 26, 2021 (the “Closing Date”), Alpha Healthcare Acquisition Corp. (“AHAC”) consummated a merger pursuant to which Hunter Merger Sub, Inc. (“Merger Sub”), a Delaware corporation and wholly owned subsidiary of AHAC, merged with Humacyte, Inc., a Delaware Corporation (“Legacy Humacyte”), with Legacy Humacyte surviving the Merger as a wholly-owned subsidiary of AHAC (such transactions, the “Merger,” and, collectively with the other transactions described in the Business Combination Agreement dated as of February 17, 2021 by and among Legacy Humacyte, Merger Sub, and AHAC (the “Merger Agreement”), the “Reverse Recapitalization”). As a result of the Merger, AHAC was renamed Humacyte, Inc. (“New Humacyte”) and Legacy Humacyte was renamed Humacyte Global, Inc.

Common Stock Warrants

Common Stock Warrants

Contingent Earnout Liability

Contingent Earnout Liability

Segments

Segments

Comprehensive loss

Comprehensive loss

Use of Estimates

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in the financial statements include stock-based compensation costs, right-of-use, or ROU assets, accruals for research and development activities, fair value of common stock, useful lives of property and equipment, redeemable convertible preferred stock and income taxes. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

2. Summary of Significant Accounting Policies (continued)

Cash and Cash Equivalents

Cash and Cash Equivalents

Redeemable Convertible Preferred Stock

Redeemable Convertible Preferred Stock

Revenue Recognition

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

2. Summary of Significant Accounting Policies (continued)

Grant Revenue

The Company recognizes funding received from grants as revenue, rather than as a reduction of research and development expenses, because the Company is the principal in conducting the research and development activities and these grants are central to the Company’s ongoing operations. The Company recognizes revenue only after the qualifying expenses related to the grants have been incurred and it is reasonably assured that the expenses will be reimbursed and the revenue will be collectible. The related costs incurred are included in research and development expense in our statements of operations and comprehensive loss.

Revenue from grants not within the scope of ASC 606 was $6.2 million and $1.5 million for the years ending December 31, 2019 and 2020, respectively.

Concentration of Credit Risk

Concentration of Credit Risk


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the three and nine months ended September 30, 2020 and 2021.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. Total cash balances exceeded insured balances by the Federal Depository Insurance Corporation as of December 31, 2019 and 2020. Cash equivalents are invested in highly rated money market funds invested only in obligations of the US government and its agencies.


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the years ended December 31, 2019 and 2020.

Other Risks and Uncertainties

Other Risks and Uncertainties

2. Summary of Significant Accounting Policies (continued)

Other Risks and Uncertainties

Net Loss per Share Attributable to Common Stockholders

Net Loss per Share Attributable to Common Stockholders


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204

Net Loss per Share Attributable to Common Stockholders

2. Summary of Significant Accounting Policies (continued)

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless inclusion of such shares would be anti-dilutive. Since the Company has only incurred losses, basic and diluted net loss per share is the same. Securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share are as follows:


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Fair Value of Financial Instruments

●

Level 1—Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets.

●

Level 3—Unobservable inputs in which little or no market data exists, therefore requiring the Company to develop its own assumptions.

2. Summary of Significant Accounting Policies (continued)

Fair Value of Financial Instruments


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Impairment of Long-Lived Assets

Property and Equipment, Net


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Impairment of Long-Lived Assets


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Accrued Research and Development

Income Taxes

2. Summary of Significant Accounting Policies (continued)

Intellectual Property

Intellectual Property

Research and Development

Research and Development

The Company expenses research and development costs as operating expenses as incurred. Research and development expenses consist primarily of:

●

salaries and related overhead expenses for personnel in research and development functions, including stock-based compensation and benefits;

●

allocation of facility lease and maintenance costs;

●

depreciation of leasehold improvements, laboratory equipment and computers;

●

costs related to purchasing raw materials for and producing product candidates for clinical trials;

●

costs related to compliance with regulatory requirements;

●

costs related to the manufacturing scale-out initiative; and

●

license fees related to in-licensed technologies.

Accrued Research and Development

Leases

Leases

2. Summary of Significant Accounting Policies (continued)

The cumulative effect of initially applying the new lease guidance on January 1, 2019 is as follows:


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements

Summary of Significant Accounting Policies (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of 10% or more of the Company's total revenue or accounts receivable balance


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

Summary of securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Summary of estimated useful lives for significant asset


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Summary of cumulative effect of initially applying the new lease guidance


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

Property and Equipment, Net (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Schedule of Property and equipment


	December 31,		September 30,
($ in thousands)	2020		2021

Scientific equipment	$	27,412	$	27,578
Computer equipment		149		154
Software		335		335
Furniture and fixtures		988		988
Leasehold improvements		26,355		26,355
		55,239		55,410
Accumulated depreciation		(14,261)		(18,911)
Property and equipment, net	$	40,978	$	36,499


	As of December 31,
($ in thousands)	2019		2020

Scientific equipment	$	27,822	$	27,412
Computer equipment		218		149
Software		340		335
Furniture and fixtures		988		988
Leasehold improvements		26,337		26,355
		55,705		55,239
Accumulated depreciation		(8,417)		(14,261)
Property and equipment, net	$	47,288	$	40,978

Accrued Expenses (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Schedule of Accrued Expenses


	December 31,		September 30,
($ in thousands)	2020		2021

Accrued external research, development and manufacturing costs	$	2,615	$	2,685
Accrued employee compensation and benefits		1,009		4,025
Accrued professional fees		968		2,712
Total	$	4,592	$	9,422


	As of December 31,
($ in thousands)	2019		2020
Accrued external research, development and manufacturing costs	$	3,872	$	2,615
Accrued employee compensation and benefits		1,260		1,009
Accrued professional fees		868		968
Total	$	6,000	$	4,592

Debt (Tables)

9 Months Ended

Sep. 30, 2021

Debt

Summary of SVB loan payable and net discount or premium balances


	September 30,
($ in thousands)	2021
Principal amount of SVB loan payable	$	20,000
Final payment amount of SVB loan payable		1,000
Net premium associated with accretion of final payment and other debt issuance costs		(3,073)
SVB loan payable, current and noncurrent		17,927
Less SVB loan payable, current portion		(3,889)
SVB loan payable, noncurrent portion	$	14,038

Summary of future minimum payments of principal and estimated payments of interest


Year ending December 31:	($ in thousands)
2021 (remainder)	$	—
2022		5,555
2023		6,667
2024		6,667
2025		1,111
Total future payments		20,000

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

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Summary of quantitative information about the leases

Leases (Tables)

12 Months Ended

Dec. 31, 2020

Leases


	Year Ended
	December 31,
($in thousands)	2019		2020
Finance lease cost
Amortization of right-of-use assets	$	2,060	$	2,060
Interest on lease liabilities		2,298		2,180
Total finance lease cost		4,358		4,240
Operating lease cost		137		152
Total lease cost	$	4,495	$	4,392


	Year Ended						Year Ended
	December 31, 2019						December 31, 2020
	Finance			Operating			Finance			Operating
($ in thousands)	Leases			Leases			Leases			Leases
Operating cash flows from leases	$	(2,298)		$	(137)		$	(2,180)		$	(182)
Financing cash flows from leases	$	(1,292)		$	—		$	(1,500)		$	—
Weighted-average remaining lease term		6.02			6.38			5.52			6.24
Weighted-average discount rate		8.50	%		8.50	%		8.50	%		8.50	%

Schedule of maturities of lease liabilities


($ in thousands)	Finance Leases		Operating Leases
Year Ended December 31, 2021	$	3,773	$	105
Year Ended December 31, 2022		3,868		105
Year Ended December 31, 2023		3,965		105
Year Ended December 31, 2024		4,065		106
Year Ended December 31, 2025		4,167		106
Thereafter		16,937		678
Total		36,775		1,205
Less: present value discount		(11,956)		(436)
Lease liabilities	$	24,819	$	769

Redeemable Convertible Preferred Stock (Tables)

12 Months Ended

Dec. 31, 2020

Redeemable Convertible Preferred Stock

Summary of redeemable convertible preferred stock

As of December 31, 2019 and December 31, 2020, redeemable convertible preferred stock consisted of the following (in thousands, except share amounts):


	Redeemable	Redeemable
	Convertible	Convertible
	Preferred	Preferred Stock
	Stock	Issued and		Carrying	Liquidation		Issuance
	Authorized	Outstanding	Value		Preference		Price
Series A redeemable convertible preferred stock	18,421,897	18,421,897	$	74,079	$	74,079	$	4.0212
Series B redeemable convertible preferred stock	24,137,647	24,137,647		127,358		136,500	$	5.6550
Series C redeemable convertible preferred stock	11,241,286	11,241,283		70,704		75,000	$	6.6717
Series D redeemable convertible preferred stock	15,812,735	15,812,735		148,848		150,000	$	9.4859
	69,613,565	69,613,562	$	420,989	$	435,579

Summary of conversion prices for each series of the redeemable convertible preferred stock


Series	Conversion Price
Series A redeemable convertible preferred stock	$	4.0212
Series B redeemable convertible preferred stock	$	5.6550
Series C redeemable convertible preferred stock	$	6.6717
Series D redeemable convertible preferred stock	$	9.4859

Stockholders' Equity (Deficit) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Schedule of activity of warrants


	Legacy
	Humacyte
	Common Stock	Private Placement		Total Common
	Warrants	Warrants	Public Warrants	Stock Warrants

Outstanding as of December 31, 2020	32,961	—	—	32,961
Common Stock Warrants issued to SVB	287,704	—	—	287,704
Common Stock Warrants as Part of the Merger	—	177,500	5,000,000	5,177,500
Warrants Exercised	(32,961)	—	—	(32,961)
Oustanding as of September 30, 2021	287,704	177,500	5,000,000	5,465,204

Summary of common stock reserved for future issuances


		September 30,
		2021
Common stock reserved for Contingent Consideration Shares		15,000,000
Exercise of options under stock plans		6,399,888
Issuance of options under stock plans		7,730,503
Shares available for grant under ESPP		1,030,033
Warrants to purchase common stock		5,465,204
		35,625,628


	December 31,
	2019	2020

Conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Conversion of Series C redeemable convertible preferred stock	11,241,286	11,241,286
Conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Exercise of options under stock plan	5,220,236	4,813,262
Issuance of options under stock plan	2,736,954	2,948,598
Warrant to purchase common stock	32,961	32,961
	77,603,716	77,408,386

Private Placement Warrants

Contingent earnout liability


	August 26,			September 30,
	2021			2021
Market price of public stock	$	10.96		$	11.61
Exercise price	$	11.50		$	11.50
Expected term (years)		5.00			4.91
Expected share price volatility		32.5	%		28.5	%
Risk-free interest rate		0.68	%		0.96	%
Estimated dividend yield		0	%		0	%


	August 26,			September 30,
	2021			2021
Current stock price	$	10.96		$	11.61
Expected share price volatility		79.6	%		78.9	%
Risk-free interest rate		1.34	%		1.55	%
Estimated dividend yield		0	%		0.0	%
Expected term (years)		10.00			10.00

Stock-based Compensation (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of assumptions on the date of grant to estimate the fair value of the stock options in the Black-Scholes option-pricing model


	Three Months Ended September 30,			Nine Months Ended September 30,
	2020		2021⁽¹⁾	2020		2021
Estimated dividend yield	0	%	—	0	%	0	%
Expected share price volatility (weighted average and range, if applicable)	91.6	%	—	91.4% (89.4% to 91.6%)		91.4% (91.0% to 92.1%)
Risk-free interest rate (weighted average and range, if applicable)	0.34	%	—	0.40% (0.34% to 0.75%)		0.68% (0.62% to 1.02%)
Expected term of options (in years)	6.0		—	6.0		6.0


	Year Ended December 31,
	2019		2020
Estimated dividend yield	0	%	0	%
Expected share price volatility	70.1%-87.7	%	89.4% - 91.6	%
Risk-free interest rate	1.76% - 2.46	%	0.34% - 0.75	%
Expected term of options (in years)	6.00		6.00

Summary of stock-based compensation expense included in the statements of operations and comprehensive loss


	Three Months Ended September 30,				Nine Months Ended September 30,
($ in thousands)	2020		2021		2020		2021
Research and development	$	308	$	486	$	781	$	1,837
General and administrative		862		1,391		2,685		5,498
Total	$	1,170	$	1,877	$	3,466	$	7,335


	December 31,		September 30,
($ in thousands)	2020		2021
Unrecognized share-based compensation cost	$	5,789	$	12,480
Expected weighted average period compensation costs to be recognized (years)		1.7		2.1


	Year Ended December 31,
($ in thousands)	2019		2020
Research and development	$	914	$	1,135
General and administrative		3,543		3,559
Total	$	4,457	$	4,694


	As of December 31,
($ in thousands)	2019		2020
Unrecognized share-based compensation cost	$	7,919	$	5,789
Expected weighted average period compensation costs to be recognized (years)		1.8		1.7

Summary of option activity


				Weighted
				Average
		Weighted		Remaining	Aggregate
		Average Exercise		Contractual Term	Intrinsic Value
	Number of Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Granted	1,838,029	$	10.28
Exercised	(188,006)	$	2.97
Forfeited	(63,397)	$	7.87
Options outstanding at September 30, 2021	6,399,888	$	7.33	6.6	$	26,705
Vested and exercisable, September 30, 2021	4,092,342	$	5.74	5.1	$	23,345
Vested and expected to vest, September 30, 2021	6,399,888	$	7.33	6.6	$	26,705


				Weighted
				Average
		Weighted		Remaining	Aggregate
	Number of	Average Exercise		Contractual Term	Intrinsic Value
	Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2018	5,638,773	$	4.69	7.4	$	21,354
Granted	621,031		8.49
Exercised	(620,831)		1.97
Forfeited	(418,737)		7.62
Options outstanding at December 31, 2019	5,220,236	$	5.22	6.5	$	17,044
Granted	480,856		9.79
Exercised	(195,239)		1.55
Forfeited	(692,591)		3.76
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Vested and exercisable, December 31, 2020	3,392,302	$	4.99	5.9	$	17,925
Vested and expected to vest, December 31, 2020	4,813,262	$	6.04	6.6	$	20,422

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Schedule of components of Company's deferred tax assets and deferred tax liabilities


	As of December 31,
($ in thousands)	2019		2020
Deferred tax assets:
Net operating loss	$	50,616	$	53,515
Capitalized research and development		19,660		32,337
Research credits		10,658		15,056
Share-based compensation		1,669		2,519
Right of use lease liability		207		177
Accrued expenses		71		57
Other		1		1
Total deferred tax asset		82,882		103,662
Less: valuation allowance		(82,193)		(101,757)
Total net deferred tax asset		689		1,905

Deferred tax liabilities:
Basis difference in fixed assets		(482)		(1,728)
Right of use lease assets		(207)		(177)
Total deferred tax liability		(689)		(1,905)
Total net deferred tax asset/(liability)	$	—	$	—

Schedule of difference between the actual income tax benefit and amount computed by applying the statutory Federal income tax rate to losses before income taxes


	December 31,
	2019				2020
($ in thousands)	Amount		Rate		Amount		Rate
Income tax benefit at statutory rate	$	(17,939)	21.0	%	$	(13,970)	21.0	%
State income taxes, net of federal benefit		(1,739)	2.0	%		(1,338)	2.0	%
Tax credits		(1,821)	2.1	%		(2,625)	3.9	%
Other nondeductible expenses		54	0.0	%		90	(0.1)	%
Deferred rate changes		16	0.0	%		16	0.0	%
Other		449	(0.5)	%		(1,736)	2.6	%
Change in valuation allowance		20,980	(24.6)	%		19,563	(29.4)	%
Provision for income taxes	$	—	0.0	%	$	—	0.0	%

Related Party Transactions (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020


	Three Months Ended September 30,		Nine Months Ended September 30,
($ in thousands)	2020	2021	2020	2021
Expenses under MOU	125	—	375	—
License expenses	20	—	70	85
Other	4	2	17	83
Total	149	2	462	168


	Year Ended
	December 31,
($ in thousands)	2019		2020
Expenses under MOU	$	422	$	500
License expenses		110		92
Other		39		28
Total	$	571	$	620

Organization and Description of Business (Details) - USD ($) $ in Thousands			3 Months Ended						9 Months Ended		12 Months Ended
	Aug. 26, 2021	Mar. 22, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Organization and Description of Business
Proceeds from merger	$ 242,400								$ 242,400
Accumulated deficit			$ 457,158						457,158		$ 388,096	$ 321,572	$ 234,289
Net loss			31,563	$ 17,198	$ 20,301	$ 17,760	$ 14,878	$ 17,674	69,062	$ 50,312	66,524	85,422
Cash and cash equivalents			$ 240,449						$ 240,449		$ 39,929	$ 93,713
Substantial Doubt about Going Concern, within One Year [true false]		true

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

Summary of Significant Accounting Policies - Basis of Presentation (Details) - shares	Aug. 26, 2021	Dec. 31, 2020
Summary of Significant Accounting Policies
Exchange ratio		0.2626%
Public warrants assumed	5,000,000
Private placement warrants assumed	177,500
Share accepting a tender offer entitles warrants to receive cash (as a percent)	50.00%

Summary of Significant Accounting Policies - Segment (Details) - segment	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Segments
Number of reportable segment	1	1	1	1	1	1
Number of operating segment					1

Summary of Significant Accounting Policies - Grant Revenue (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended		86 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Nov. 30, 2013	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from grants not within the scope of ASC 606				$ 200	$ 900	$ 1,100	$ 1,400	$ 1,500	$ 6,200	$ 1,600
Department of Defense grants \| Work on bioengineered blood vessels for vascular trauma
Disaggregation of Revenue [Line Items]
Grants	$ 4,000
Department of Defense grants \| Work to support human tissue engineered blood vessels for vascular reconstruction
Disaggregation of Revenue [Line Items]
Grants		$ 7,100
Department of Defense grants \| Reimbursement of certain allowable costs related to grants
Disaggregation of Revenue [Line Items]
Recognized revenue				200	600	1,100	1,000
National Institutes of Health grant \| Reimbursement of certain allowable costs related to grants
Disaggregation of Revenue [Line Items]
Recognized revenue				$ 0	$ 300	$ 0	$ 300
National Institutes of Health grant \| Work to support bioengineered grafts for peripheral vascular disease
Disaggregation of Revenue [Line Items]
Grants			$ 1,600

Summary of Significant Accounting Policies -Concentration of Credit Risk (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Revenue \| Customer concentration
Concentration Risk [Line Items]
Concentration of Credit Risk	100.00%	98.00%	100.00%	96.00%	95.00%	100.00%
Revenue \| Customer concentration \| Grant A
Concentration Risk [Line Items]
Concentration of Credit Risk						28.00%
Revenue \| Customer concentration \| Grant B
Concentration Risk [Line Items]
Concentration of Credit Risk		0.00%		11.00%	10.00%	38.00%
Revenue \| Customer concentration \| Grant C
Concentration Risk [Line Items]
Concentration of Credit Risk	100.00%	68.00%	100.00%	65.00%	67.00%	34.00%
Revenue \| Customer concentration \| Grant D
Concentration Risk [Line Items]
Concentration of Credit Risk		30.00%		20.00%	18.00%
Accounts Receivable \| Credit concentration
Concentration Risk [Line Items]
Concentration of Credit Risk			100.00%		100.00%	100.00%
Accounts Receivable \| Credit concentration \| Grant B
Concentration Risk [Line Items]
Concentration of Credit Risk						67.00%
Accounts Receivable \| Credit concentration \| Grant C
Concentration Risk [Line Items]
Concentration of Credit Risk			100.00%		100.00%	33.00%

Summary of Significant Accounting Policies - Net Loss per Share Attributable to Common Stockholders (Details) - shares	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Contingent consideration (in shares)	15,000,000
Series A redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		18,421,897	18,421,897	18,421,897
Series B redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		24,137,647	24,137,647	24,137,647
Series C redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		11,241,283	11,241,283	11,241,283
Series D redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		15,812,735	15,812,735	15,812,735
Exercise of options under stock plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share	6,399,888	4,516,907	4,813,262	5,220,236
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share	5,465,204	32,961	32,961	32,961

Summary of Significant Accounting Policies - Property and Equipment, Net (Details)	12 Months Ended
	Dec. 31, 2020
Scientific equipment. \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Scientific equipment. \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Computer equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Software
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Furniture and fixtures \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Furniture and fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years

Summary of Significant Accounting Policies - Impairment of Long-Lived Assets and Income Taxes (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended		24 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Impairment of Long-Lived Assets
Impairment of long-lived assets	$ 0	$ 0	$ 0
Income Taxes
Uncertain tax positions		0		$ 0
Accrued interest or penalties related to uncertain tax positions		$ 0		0
interest or penalties related to uncertain tax positions expensed				$ 0

Summary of Significant Accounting Policies - Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit	$ (457,158)	$ (388,096)	$ (321,572)	$ (234,289)
Lease liabilities, Finance leases		24,819	26,300
Finance lease right-of-use assets	21,947	23,492	25,552
Operating right-of-use assets	$ 738	769	897
Lease liabilities, Operating leases		$ 769	$ 900
Cumulative Effect Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit				(1,861)
Lease liabilities, Finance leases				27,600
Finance lease right-of-use assets				27,612
Operating right-of-use assets				923
Lease liabilities, Operating leases				900
ASU 2016-02 \| Cumulative Effect Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accumulated deficit				$ 1,900

The cumulative amount of the reporting entity's undistributed earnings or deficit.

Organization and Description of Business

Summary of Significant Accounting Policies - New lease guidance on January 1, 2019 (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Assets
Building asset				$ 25,091
Finance lease right-of-use assets, net	$ 21,947	$ 23,492	$ 25,552
Operating lease right-of-use assets, net	738	769	897
Liabilities and stockholders' deficit
Accrued expenses	9,422	4,592	6,000	7,049
Facility financing obligation, current portion				276
Finance lease obligation, current portion	1,915	1,729	1,500
Operating lease obligation, current portion	44	42	70
Facility financing obligation, net of current portion				22,955
Finance lease obligation, net of current portion	21,627	23,090	24,819
Operating lease obligation, net of current portion	693	727	829
Accumulated deficit	$ (457,158)	$ (388,096)	$ (321,572)	(234,289)
Cumulative Effect Adjustment
Assets
Building asset				(25,091)
Finance lease right-of-use assets, net				27,612
Operating lease right-of-use assets, net				923
Liabilities and stockholders' deficit
Accrued expenses				(1)
Facility financing obligation, current portion				(276)
Finance lease obligation, current portion				1,292
Operating lease obligation, current portion				55
Facility financing obligation, net of current portion				(22,955)
Finance lease obligation, net of current portion				26,319
Operating lease obligation, net of current portion				870
Accumulated deficit				(1,861)
Beginning Balance, As Adjusted
Assets
Finance lease right-of-use assets, net				27,612
Operating lease right-of-use assets, net				923
Liabilities and stockholders' deficit
Accrued expenses				7,048
Finance lease obligation, current portion				1,292
Operating lease obligation, current portion				55
Finance lease obligation, net of current portion				26,319
Operating lease obligation, net of current portion				870
Accumulated deficit				(236,150)
ASU 2016-02 \| Cumulative Effect Adjustment
Liabilities and stockholders' deficit
Accumulated deficit				$ 1,900

Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 55,410		$ 55,410		$ 55,239	$ 55,705
Accumulated depreciation	(18,911)		(18,911)		(14,261)	(8,417)
Property and equipment, net	36,499		36,499		40,978	47,288
Depreciation expense	1,500	$ 1,600	4,650	$ 4,729	6,291	4,689
Scientific equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	27,578		27,578		27,412	27,822
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	154		154		149	218
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	335		335		335	340
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	988		988		988	988
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 26,355		$ 26,355		$ 26,355	$ 26,337

Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Accrued Expenses
Accrued external research, development and manufacturing costs	$ 2,685	$ 2,615	$ 3,872
Accrued employee compensation and benefits	4,025	1,009	1,260
Accrued professional fees	2,712	968	868
Total	$ 9,422	$ 4,592	$ 6,000	$ 7,049

Debt - PPP (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended		12 Months Ended
Debt - PPP (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Proceeds from debt instruments			$ 3,251	$ 3,251
Gain on PPP loan forgiveness		$ 3,284
Paycheck Protection Program
Debt Instrument [Line Items]
Proceeds from debt instruments	$ 3,300
Gain on PPP loan forgiveness		$ 3,284

Leases - Paragraphs (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Lease, Liability			$ 769	$ 900
Finance Lease, Liability			24,819	26,300
Operating Lease, Right-of-Use Asset		$ 738	769	897
Finance lease right-of-use assets, net		$ 21,947	$ 23,492	$ 25,552
Maximum
Gain (Loss) on Termination of Lease	$ 100

Leases - Costs (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
Leases - Costs (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Finance lease cost
Amortization of right-of-use assets			$ 2,060	$ 2,060
Interest on lease liabilities			2,180	2,298
Total finance lease cost			4,240	4,358
Operating lease cost	$ 31	$ 71	152	137
Total lease cost			$ 4,392	$ 4,495

Leases - Cash flows (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
Leases - Cash flows (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Leases
Operating cash flows from leases, Operating Leases			$ (182)	$ (137)
Operating cash flows from leases, Finance Leases			(2,180)	(2,298)
Financing cash flows from leases	$ (1,277)	$ (1,107)	$ (1,500)	$ (1,292)
Weighted-average remaining lease term, Operating Leases			6 years 2 months 26 days	6 years 4 months 17 days
Weighted-average remaining lease term, Finance Leases			5 years 6 months 7 days	6 years 7 days
Weighted-average discount rate, Operating Leases			8.50%	8.50%
Weighted-average discount rate, Finance Leases			8.50%	8.50%

Leases - Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating leases
2021	$ 105
2022	105
2023	105
2024	106
2025	106
Thereafter	678
Total, Operating leases	1,205
Less: present value discount, Operating leases	436
Lease liabilities, Operating leases	769	$ 900
Finance leases
2021	3,773
2022	3,868
2023	3,965
2024	4,065
2025	4,167
Thereafter	16,937
Total, Finance leases	36,775
Less: present value discount, Finance leases	11,956
Lease liabilities, Finance leases	$ 24,819	$ 26,300

Redeemable Convertible Preferred Stock - Preferred Stock Terms (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Temporary Equity [Line Items]
Redeemable Convertible Preferred Stock, Authorized	0	69,613,565	69,613,565
Redeemable Convertible Preferred Stock, Issued and Outstanding	0	69,613,562	69,613,562
Redeemable Convertible Preferred Stock, Carrying Value		$ 420,989	$ 420,989
Redeemable Convertible Preferred Stock, Liquidation Preference	$ 0	$ 435,579	$ 435,579
Series A redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable Convertible Preferred Stock, Authorized		18,421,897
Redeemable Convertible Preferred Stock, Issued and Outstanding		18,421,897
Redeemable Convertible Preferred Stock, Carrying Value		$ 74,079
Redeemable Convertible Preferred Stock, Liquidation Preference		$ 74,079
Redeemable Convertible Preferred Stock, Issuance Price		$ 4.0212
Series B redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable Convertible Preferred Stock, Authorized		24,137,647
Redeemable Convertible Preferred Stock, Issued and Outstanding		24,137,647
Redeemable Convertible Preferred Stock, Carrying Value		$ 127,358
Redeemable Convertible Preferred Stock, Liquidation Preference		$ 136,500
Redeemable Convertible Preferred Stock, Issuance Price		$ 5.6550
Series C redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable Convertible Preferred Stock, Authorized		11,241,286
Redeemable Convertible Preferred Stock, Issued and Outstanding		11,241,283
Redeemable Convertible Preferred Stock, Carrying Value		$ 70,704
Redeemable Convertible Preferred Stock, Liquidation Preference		$ 75,000
Redeemable Convertible Preferred Stock, Issuance Price		$ 6.6717
Series D redeemable convertible preferred stock
Temporary Equity [Line Items]
Redeemable Convertible Preferred Stock, Authorized		15,812,735
Redeemable Convertible Preferred Stock, Issued and Outstanding		15,812,735
Redeemable Convertible Preferred Stock, Carrying Value		$ 148,848
Redeemable Convertible Preferred Stock, Liquidation Preference		$ 150,000
Redeemable Convertible Preferred Stock, Issuance Price		$ 9.4859

Redeemable Convertible Preferred Stock (Details)	Dec. 31, 2020 USD ($)
Fresenius Medical Care \| Private placement
Class of Stock [Line Items]
Right to purchase common stock granted	$ 30.0

Redeemable Convertible Preferred Stock - Election of Directors (Details)	12 Months Ended
	Dec. 31, 2020 individual
Fresenius Medical Care
Temporary Equity [Line Items]
Number of representative to attend, in a non-voting observer capacity designated by related party	1
Series A redeemable convertible preferred stock
Temporary Equity [Line Items]
Number of individual designated for board of director by holder of stock	1
Series B redeemable convertible preferred stock
Temporary Equity [Line Items]
Number of individual designated for board of director by holder of stock	2
Series C redeemable convertible preferred stock
Temporary Equity [Line Items]
Number of individual designated for board of director by holder of stock	1

Redeemable Convertible Preferred Stock - Conversion to Common Stock (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares
Redeemable Convertible Preferred Stock
Minimum offering price required for automatic conversion \| $ / shares	$ 2.7401
Minimum aggregate gross proceeds required for automatic conversion \| $	$ 100.0
Percentage of written request of holder required for automatic conversion	60.00%

Redeemable Convertible Preferred Stock- Conversion prices (Details)	Dec. 31, 2020 $ / shares
Temporary Equity [Line Items]
Conversion ratio	1
Series A redeemable convertible preferred stock
Temporary Equity [Line Items]
Conversion Price	$ 4.0212
Series B redeemable convertible preferred stock
Temporary Equity [Line Items]
Conversion Price	5.6550
Series C redeemable convertible preferred stock
Temporary Equity [Line Items]
Conversion Price	6.6717
Series D redeemable convertible preferred stock
Temporary Equity [Line Items]
Conversion Price	$ 9.4859

Redeemable Convertible Preferred Stock - Liquidation (Details)	12 Months Ended
	Dec. 31, 2020 $ / shares
Temporary Equity [Line Items]
Number of times of liquidation preference per share holder is entitled to receive	1.25
Series A redeemable convertible preferred stock
Temporary Equity [Line Items]
Liquidation preference per share	$ 4.0212
Series B redeemable convertible preferred stock
Temporary Equity [Line Items]
Liquidation preference per share	5.6550
Series C redeemable convertible preferred stock
Temporary Equity [Line Items]
Liquidation preference per share	$ 6.6717
Percentage of holders required for approval of liquidation preference	80.00%
Series D redeemable convertible preferred stock
Temporary Equity [Line Items]
Liquidation preference per share	$ 9.4859

Stockholders' Equity (Deficit) - Common Stock (Details) $ / shares in Units, $ in Thousands		3 Months Ended	9 Months Ended	12 Months Ended
	Aug. 26, 2021 USD ($) $ / shares shares	Sep. 30, 2021 $ / shares shares	Sep. 30, 2021 USD ($) Vote $ / shares shares	Dec. 31, 2020 Vote $ / shares shares	Dec. 31, 2019 $ / shares shares
Proceeds from merger	$ 242,400		$ 242,400
Assets	$ 100
Common stock, shares outstanding \| shares	103,003,384	103,003,384	103,003,384	5,822,396	5,627,157
Common stock, par value \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Dividends declared \| $ / shares			$ 0	$ 0
Number of vote per common share held \| Vote				1
Common stock, authorized \| shares		250,000,000	250,000,000	340,216,780	340,216,780
Common Stock
Issuance of common stock upon the Merger and related PIPE Financing, net of issuance costs \| shares	27,346,449	27,346,449
Proceeds from merger	$ 242,400
Transaction costs	$ 3,900
Common stock, shares outstanding \| shares	103,003,384
Common stock, par value \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001
Number of vote per common share held \| Vote			1
Common stock, authorized \| shares		250,000,000	250,000,000
Alpha Healthcare Acquisition Corp. and Hunter Merger Sub, Inc. \| Common Stock
Contingent consideration liability	$ 15,200
Assets	$ 100

Stockholders' Equity (Deficit) - Common stock for future issuances (Details) - shares	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Reserved common stock for future issuances	35,625,628	77,408,386	77,603,716
Series A redeemable convertible preferred stock
Class of Stock [Line Items]
Reserved common stock for future issuances		18,421,897	18,421,897
Series B redeemable convertible preferred stock
Class of Stock [Line Items]
Reserved common stock for future issuances		24,137,647	24,137,647
Series C redeemable convertible preferred stock
Class of Stock [Line Items]
Reserved common stock for future issuances		11,241,286	11,241,286
Series D redeemable convertible preferred stock
Class of Stock [Line Items]
Reserved common stock for future issuances		15,812,735	15,812,735
Common stock reserved for Contingent Consideration Shares
Class of Stock [Line Items]
Reserved common stock for future issuances	15,000,000
Exercise of options under stock plan
Class of Stock [Line Items]
Reserved common stock for future issuances	6,399,888	4,813,262	5,220,236
Issuance of options under stock plan
Class of Stock [Line Items]
Reserved common stock for future issuances	7,730,503	2,948,598	2,736,954
Shares available for grant under ESPP
Class of Stock [Line Items]
Reserved common stock for future issuances	1,030,033
Warrants to purchase common stock
Class of Stock [Line Items]
Reserved common stock for future issuances	5,465,204	32,961	32,961

Stock-based Compensation (Details) - $ / shares	1 Months Ended	9 Months Ended	12 Months Ended
Stock-based Compensation (Details) - $ / shares	Jan. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of options remaining available for grant		7,730,503	2,948,598
Outstanding awards		6,399,888	4,813,262	5,220,236	5,638,773
Contractual term		10 years	10 years
Vesting period	3 years		36 months
Commencement of involuntary termination term prior to effective date of corporate transaction		30 days	30 days
End of involuntary termination term after effective date of corporate transaction		12 months	12 months
Granted		1,838,029	480,856	621,031
Exercise price		$ 10.28	$ 9.79	$ 8.49
Minimum
Vesting period		36 months
Maximum
Vesting period		48 months
Chief Executive Officer [Member]
Vesting period	3 years
Granted	1,312,984
Exercise price	$ 10.28

Stock-based Compensation - Fair value of the stock options (Details)	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Assumptions on the date of grant to estimate the fair value of the stock options
Estimated dividend yield	0.00%	0.00%	0.00%	0.00%	0.00%
Expected price volatility	91.60%	91.40%	91.40%
Expected share price volatility, minimum		91.00%	89.40%		89.40%	70.10%
Expected share price volatility, maximum		92.10%	91.60%		91.60%	87.70%
Risk-free interest rate	0.34%	0.68%	0.40%
Risk-free interest rate, minimum		0.62%	0.34%		0.34%	1.76%
Risk-free interest rate, maximum		1.02%	0.75%		0.75%	2.46%
Expected term of options (in years)	6 years	6 years	6 years		6 years	6 years

Stock-based Compensation - Available options (Details) - shares	Sep. 30, 2021	Dec. 31, 2020
Stock-based Compensation
Number of options remaining available for grant	7,730,503	2,948,598

Stock-based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,877	$ 1,170	$ 7,335	$ 3,466	$ 4,694	$ 4,457
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	486	308	1,837	781	1,135	914
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense	$ 1,391	$ 862	$ 5,498	$ 2,685	$ 3,559	$ 3,543

Stock-based Compensation - Unrecognized cost (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Stock-based Compensation
Unrecognized share-based compensation cost	$ 12,480	$ 5,789	$ 7,919
Expected weighted average period compensation costs to be recognized (years)	2 years 1 month 6 days	1 year 8 months 12 days	1 year 9 months 18 days

Stock-based Compensation - Option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of Shares
Options outstanding at the beginning	4,813,262	5,220,236	5,638,773
Granted	1,838,029	480,856	621,031
Exercised	(188,006)	(195,239)	(620,831)
Forfeited	(63,397)	(692,591)	(418,737)
Options outstanding at the end	6,399,888	4,813,262	5,220,236	5,638,773
Vested and exercisable at the end of period	4,092,342	3,392,302
Vested and expected to vest at the end	6,399,888	4,813,262
Weighted Average Exercise Price Per Share
Options outstanding at the beginning (in dollars per share)	$ 6.04	$ 5.22	$ 4.69
Granted (in dollars per share)	10.28	9.79	8.49
Exercised (in dollars per share)	2.97	1.55	1.97
Forfeited (in dollars per share)	7.87	3.76	7.62
Options outstanding at the end (in dollars per share)	7.33	6.04	$ 5.22	$ 4.69
Vested and exercisable at the end of period (in dollars per share)	5.74	4.99
Vested and expected to vest at the end (in dollars per share)	$ 7.33	$ 6.04
Weighted Average Remaining Contractual Term and Aggregate Intrinsic Value
Options outstanding (in years)	6 years 7 months 6 days	6 years 7 months 6 days	6 years 6 months	7 years 4 months 24 days
Vested and exercisable at the end of period (in years)	5 years 1 month 6 days	5 years 10 months 24 days
Vested and expected to vest at the end (in years)	6 years 7 months 6 days	6 years 7 months 6 days
Options outstanding at the beginning (in dollars)	$ 20,422	$ 17,044	$ 21,354
Options outstanding at the end (in dollars)	26,705	20,422	$ 17,044	$ 21,354
Vested and exercisable at the end of period (in years)	23,345	17,925
Vested and expected to vest at the end (in dollars)	$ 26,705	$ 20,422

Stock-based Compensation - Other information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stock-based Compensation
Total intrinsic value of options exercised	$ 1.4	$ 4.0
Weighted-average grant-date fair value per share of options granted	$ 7.26	$ 5.84

Income Taxes - Deferred tax assets and deferred tax liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss	$ 53,515	$ 50,616
Intangible assets	32,337	19,660
Research credits	15,056	10,658
Share-based compensation	2,519	1,669
Right of use lease liability	177	207
Accrued expenses	57	71
Other	1	1
Total deferred tax asset	103,662	82,882
Less: valuation allowance	(101,757)	(82,193)
Total net deferred tax asset	1,905	689
Deferred tax liabilities:
Basis difference in fixed assets	(1,728)	(482)
Right of Use Lease Assets	(177)	(207)
Total deferred tax liability	$ (1,905)	$ (689)

Income Taxes - Tax reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Income tax benefit at statutory rate, Amount					$ (13,970)	$ (17,939)
State income taxes, net of federal benefit, Amount					(1,338)	(1,739)
Tax credits, Amount					(2,625)	(1,821)
Other nondeductible expenses, Amount					90	54
Deferred rate changes, Amount					16	16
Other, Amount					(1,736)	449
Change in valuation allowance, Amount					$ 19,563	$ 20,980
Income tax benefit at statutory rate, Rate					21.00%	21.00%
State income taxes, net of federal benefit, Rate					2.00%	2.00%
Tax credits, Rate					3.90%	2.10%
Other nondeductible expenses, Rate					(0.10%)	0.00%
Deferred rate changes, Rate					0.00%	0.00%
Other, Rate					2.60%	(0.50%)
Change in valuation allowance, Rate					(29.40%)	(24.60%)
Effective tax rate	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%

Income Taxes - Additional information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Percent of limitation on taxable income	80.00%
Effective federal tax rate	$ (13,970)	$ (17,939)
Effective federal tax rate	21.00%	21.00%
Foreign
Operating Loss Carryforwards [Line Items]
Operating loss	$ 232,700
Operating loss	71,500
Tax credit carryforwards		$ 10,700
State
Operating Loss Carryforwards [Line Items]
Operating loss	232,600
Tax credit carryforwards	$ 15,100

Retirement Plan (Details) $ in Millions	12 Months Ended
Retirement Plan (Details) $ in Millions	Dec. 31, 2020 USD ($) plan	Dec. 31, 2019 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Number of plans \| plan	2,000
Qualified Plan
Defined Contribution Plan Disclosure [Line Items]
Employer's contribution for retirement plan \| $	$ 0.6	$ 0.6
Plan 401 (K)
Defined Contribution Plan Disclosure [Line Items]
Employer's contribution Percentage for retirement plan	4.00%

Commitments and Contingencies - Duke University (Details) - Duke university - License agreement - shares	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Agreement expiration term after first commercial sale	4 years	4 years
Threshold notice period required to terminate the agreement	3 months	3 months
Collaborative Arrangement, Shares Issued In Connection With License Agreement	52,693	52,693

Commitments and Contingencies - Yale University (Details) - Yale university - USD ($) $ in Millions	1 Months Ended		9 Months Ended	12 Months Ended
	Aug. 31, 2019	Feb. 28, 2014	Sep. 30, 2021	Dec. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone payments upon achievement of certain regulatory milestones			$ 0.2
Milestone payments upon achievement of certain commercial milestones			$ 0.6
License agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Threshold notice period required to terminate the agreement			90 days	90 days
License agreement related to coatings for small diameter vessels to inhibit clotting
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative Arrangement, Maximum Annual Maintenance Fee	$ 0.1	$ 0.1
License agreement related to bioartificial vascular pancreas
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative Arrangement, Maximum Annual Maintenance Fee			$ 0.1
License agreement related to tubular prostheses
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Collaborative Arrangement, Maximum Annual Maintenance Fee	$ 0.1

Related Party Transactions (Details) - USD ($) $ in Millions		1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Aug. 26, 2021	Aug. 31, 2021	Jun. 30, 2018	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2023	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2021
Related Party Transaction [Line Items]
Proceeds from PIPE	$ 175.0
Common stock, shares issued							5,822,396	5,627,157	103,003,384
Fresenius Medical Care
Related Party Transaction [Line Items]
Financing amount			$ 150.0
Shares issued for conversion of preferred shares	15,812,735
Proceeds from PIPE		$ 25.0
Common stock, shares issued		2,500,000
Dr. Niklason, President, CEO and member of board of directors
Related Party Transaction [Line Items]
Aggregate amount						$ 2.5
Payments made				$ 0.1	$ 0.4		$ 0.5	$ 0.4

Related Party Transactions - Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Total	$ 2	$ 149	$ 168	$ 462	$ 620	$ 571
Expenses under MOU
Related Party Transaction [Line Items]
Total		125		375	500	422
License expenses
Related Party Transaction [Line Items]
Total		20	85	70	92	110
Other
Related Party Transaction [Line Items]
Total	$ 2	$ 4	$ 83	$ 17	$ 28	$ 39

Subsequent Events - Stock option grants (Details) - $ / shares	1 Months Ended	9 Months Ended	12 Months Ended
	Jan. 31, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 22, 2021
Subsequent Event [Line Items]
Option to purchase shares of common stock		1,838,029	480,856	621,031
Exercise price		$ 10.28	$ 9.79	$ 8.49
Number of shares vested as of the issuance date		6,399,888	4,813,262
Vesting period	3 years		36 months
Dr. Niklason
Subsequent Event [Line Items]
Option to purchase shares of common stock	1,312,984
Exercise price	$ 10.28
Vesting period	3 years
Subsequent event \| Dr. Niklason
Subsequent Event [Line Items]
Option to purchase shares of common stock	1,312,984
Exercise price	$ 10.28
Number of shares vested as of the issuance date					0
Vesting period	3 years
Subsequent event \| Mr. Sander
Subsequent Event [Line Items]
Option to purchase shares of common stock	183,817
Exercise price	$ 10.28
Number of shares vested as of the issuance date					0

Subsequent Events - Merger (Details) - Subsequent event	Feb. 17, 2021 USD ($)
Subsequent Event [Line Items]
Amount of common stock investors have agreed to purchase	$ 175,000,000
Intangible Assets, Net (Including Goodwill)	$ 0

Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Current assets
Cash and cash equivalents	$ 240,449	$ 39,929	$ 93,713
Accounts receivable	240	113	601
Prepaid expenses	3,490	1,407	640
Total current assets	244,179	41,449	94,954
Finance lease right-of-use assets, net	21,947	23,492	25,552
Operating lease right-of-use assets, net	738	769	897
Property and equipment, net	36,499	40,978	47,288
Total assets	303,363	106,688	168,691
Current liabilities
Accounts payable	5,830	2,274	3,272
Accrued expenses	9,422	4,592	6,000	$ 7,049
SVB loan payable, current portion	3,889
Finance lease obligation, current portion	1,915	1,729	1,500
Deferred payroll tax, current portion	145	145
Operating lease obligation, current portion	44	42	70
PPP loan payable, current portion		2,451
Total current liabilities	21,245	11,233	10,842
Contingent earnout liability	169,200
Finance lease obligation, net of current portion	21,627	23,090	24,819
SVB loan payable, net of current portion	14,038
Operating lease obligation, net of current portion	693	727	829
Common stock warrant liabilities	555
Deferred payroll tax, net of current portion	144	144
PPP loan payable, net of current portion		822
Total liabilities	227,502	36,016	36,490
Commitments and contingencies (Note 11)
Redeemable convertible preferred stock (Series A, B, C and D) $0.001 par value, 0 and 69,613,565 shares authorized as of September 30, 2021 and December 31, 2020, respectively; 0 and 69,613,562 shares outstanding as of September 30, 2021 and December 31, 2020, respectively; liquidation preference of $0 and $435,579 as of September 30, 2021 and December 31, 2020, respectively.		420,989	420,989
Stockholders' equity (deficit)
Preferred stock, $0.0001 par value; 20,000,000 and 0 shares designated as of September 30, 2021 and December 31, 2020; 0 shares issued and outstanding as of September 30, 2021 and December 31, 2020
Common stock, $0.0001 and $0.0001 par value as of September 30, 2021 and December 31, 2020, respectively; 250,000,000 and 340,216,780 shares authorized as of September 30, 2021 and December 31, 2020, respectively; 103,003,384 and 5,822,396 shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively.	10	1	1
Additional paid-in capital	533,009	37,778	32,783
Accumulated deficit	(457,158)	(388,096)	(321,572)	$ (234,289)
Total stockholders' equity (deficit)	75,861	(350,317)	(288,788)
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	$ 303,363	$ 106,688	$ 168,691

Balance sheet (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Aug. 26, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance Sheets
Redeemable convertible preferred stock, par value	$ 0.001		$ 0.001	$ 0.001
Redeemable convertible preferred stock, shares authorized	0		69,613,565	69,613,565
Redeemable convertible preferred stock, shares outstanding	0		69,613,562	69,613,562
Redeemable convertible preferred stock, liquidation preference	$ 0		$ 435,579	$ 435,579
Preferred stock, par value	$ 0.0001		$ 0.0001
Preferred stock, shares designated	20,000,000		0
Preferred stock, shares issued	0		0
Preferred stock, shares outstanding	0		0
Common stock, par value	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Common stock, shares authorized	250,000,000		340,216,780	340,216,780
Common stock, shares issued	103,003,384		5,822,396	5,627,157
Common stock, shares outstanding	103,003,384	103,003,384	5,822,396	5,627,157

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Condensed Consolidated Statements of Operations and Comprehensive Loss
Grant Revenue	$ 241	$ 914	$ 1,086	$ 1,367	$ 1,491	$ 6,187
Operating expenses:
Research and development (includes related party expenses of $2 and $149 for the three months ended September 30, 2021 and 2020 and $168 and $462 for the nine months ended September 30, 2021 and 2020)	15,386	14,692	45,091	40,879	54,078	75,603
General and administrative	5,398	3,435	15,576	9,416	12,013	16,275
Total operating expenses	20,784	18,127	60,667	50,295	66,091	91,878
Loss from operations	(20,543)	(17,213)	(59,581)	(48,928)	(64,600)	(85,691)
Other expenses, net:
Interest income	3	2	6	277	278	2,567
Change in fair value of contingent earnout liability	(9,768)		(9,768)
Interest expense	(1,204)	(549)	(2,952)	(1,661)	(2,202)	(2,298)
Transaction costs expensed	(49)		(49)
Change in fair value of common stock warrant liabilities	(2)		(2)
Gain on PPP loan forgiveness			3,284
Total other expenses, net	(11,020)	(547)	(9,481)	(1,384)	(1,924)	269
Net loss and comprehensive loss	$ (31,563)	$ (17,760)	$ (69,062)	$ (50,312)	$ (66,524)	$ (85,422)
Net loss per share attributable to common stockholders, basic	$ (0.72)	$ (3.07)	$ (3.69)	$ (8.74)
Net loss per share attributable to common stockholders, diluted	$ (0.72)	$ (3.07)	$ (3.69)	$ (8.74)
Weighted-average shares outstanding used in computing net loss per share attributable to common stockholders, basic	43,950,856	5,788,130	18,728,471	5,755,418
Weighted-average shares outstanding used in computing net loss per share attributable to common stockholders, diluted	43,950,856	5,788,130	18,728,471	5,755,418
Net loss per share attributable to common stockholders, basic and diluted					$ (11.54)	$ (16.17)
Weighted-average shares outstanding used in computing net loss per share attributable to common stockholders, basic and diluted					5,765,688	5,283,628

Condensed Consolidated Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Condensed Consolidated Statements of Operations and Comprehensive Loss
Related party expenses	$ 2	$ 149	$ 168	$ 462	$ 620	$ 571

Condensed Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Redeemable Convertible Preferred Stock.	Common Stock	Additional Paid-in Capital	Accumulated Deficit Cumulative Effect Adjustment	Accumulated Deficit	Cumulative Effect Adjustment	Total
Balance at the beginning at Dec. 31, 2018	$ 420,989
Balance at the beginning (in shares) at Dec. 31, 2018	69,613,562
Balance at the end at Dec. 31, 2019	$ 420,989						$ 420,989
Balance at the end (in shares) at Dec. 31, 2019	69,613,562						69,613,562
Balance at the beginning at Dec. 31, 2018		$ 1	$ 27,108		$ (234,289)		$ (207,180)
Balance at the beginning (in shares) at Dec. 31, 2018		5,006,326
Equity
Proceeds from the exercise of stock options			1,218				$ 1,218
Proceeds from the exercise of stock options (in shares)		620,831					620,831
Net loss					(85,422)		$ (85,422)
Stock-based compensation			4,457				4,457
Balance at the end (ASU 2016-02) at Dec. 31, 2019				$ (1,861)		$ (1,861)
Balance at the end at Dec. 31, 2019		$ 1	32,783		(321,572)		(288,788)
Balance at the end (in shares) at Dec. 31, 2019		5,627,157
Balance at the end at Mar. 31, 2020	$ 420,989
Balance at the end (in shares) at Mar. 31, 2020	69,613,562
Equity
Proceeds from the exercise of stock options			175				175
Proceeds from the exercise of stock options (in shares)		148,159
Net loss					(17,674)		(17,674)
Stock-based compensation			1,182				1,182
Balance at the end at Mar. 31, 2020		$ 1	34,140		(339,246)		(305,105)
Balance at the end (in shares) at Mar. 31, 2020		5,775,316
Balance at the beginning at Dec. 31, 2019	$ 420,989						$ 420,989
Balance at the beginning (in shares) at Dec. 31, 2019	69,613,562						69,613,562
Balance at the end at Sep. 30, 2020	$ 420,989
Balance at the end (in shares) at Sep. 30, 2020	69,613,562
Balance at the beginning (ASU 2016-02) at Dec. 31, 2019				(1,861)		(1,861)
Balance at the beginning at Dec. 31, 2019		$ 1	32,783		(321,572)		$ (288,788)
Balance at the beginning (in shares) at Dec. 31, 2019		5,627,157
Equity
Net loss							(50,312)
Balance at the end at Sep. 30, 2020		$ 1	36,484		(371,884)		(335,399)
Balance at the end (in shares) at Sep. 30, 2020		5,788,877
Balance at the beginning at Dec. 31, 2019	$ 420,989						$ 420,989
Balance at the beginning (in shares) at Dec. 31, 2019	69,613,562						69,613,562
Balance at the end at Dec. 31, 2020	$ 420,989						$ 420,989
Balance at the end (in shares) at Dec. 31, 2020	69,613,562						69,613,562
Balance at the beginning (ASU 2016-02) at Dec. 31, 2019				$ (1,861)		$ (1,861)
Balance at the beginning at Dec. 31, 2019		$ 1	32,783		(321,572)		$ (288,788)
Balance at the beginning (in shares) at Dec. 31, 2019		5,627,157
Equity
Proceeds from the exercise of stock options			301				$ 301
Proceeds from the exercise of stock options (in shares)		195,239					195,239
Net loss					(66,524)		$ (66,524)
Stock-based compensation			4,694				4,694
Balance at the end at Dec. 31, 2020		$ 1	37,778		(388,096)		(350,317)
Balance at the end (in shares) at Dec. 31, 2020		5,822,396
Balance at the beginning at Mar. 31, 2020	$ 420,989
Balance at the beginning (in shares) at Mar. 31, 2020	69,613,562
Balance at the end at Jun. 30, 2020	$ 420,989
Balance at the end (in shares) at Jun. 30, 2020	69,613,562
Balance at the beginning at Mar. 31, 2020		$ 1	34,140		(339,246)		(305,105)
Balance at the beginning (in shares) at Mar. 31, 2020		5,775,316
Equity
Proceeds from the exercise of stock options			48				48
Proceeds from the exercise of stock options (in shares)		11,761
Net loss					(14,878)		(14,878)
Stock-based compensation			1,114				1,114
Balance at the end at Jun. 30, 2020		$ 1	35,302		(354,124)		(318,821)
Balance at the end (in shares) at Jun. 30, 2020		5,787,077
Balance at the end at Sep. 30, 2020	$ 420,989
Balance at the end (in shares) at Sep. 30, 2020	69,613,562
Equity
Proceeds from the exercise of stock options			12				12
Proceeds from the exercise of stock options (in shares)		1,800
Net loss					(17,760)		(17,760)
Stock-based compensation			1,170				1,170
Balance at the end at Sep. 30, 2020		$ 1	36,484		(371,884)		(335,399)
Balance at the end (in shares) at Sep. 30, 2020		5,788,877
Balance at the beginning at Dec. 31, 2020	$ 420,989						$ 420,989
Balance at the beginning (in shares) at Dec. 31, 2020	69,613,562						69,613,562
Balance at the end at Mar. 31, 2021	$ 420,989
Balance at the end (in shares) at Mar. 31, 2021	69,613,562
Balance at the beginning at Dec. 31, 2020		$ 1	37,778		(388,096)		$ (350,317)
Balance at the beginning (in shares) at Dec. 31, 2020		5,822,396
Equity
Proceeds from the exercise of stock options			206				206
Proceeds from the exercise of stock options (in shares)		116,149
Net loss					(20,301)		(20,301)
Stock-based compensation			2,528				2,528
Issuance of warrants in conjunction with debt			2,360				2,360
Balance at the end at Mar. 31, 2021		$ 1	42,872		(408,397)		(365,524)
Balance at the end (in shares) at Mar. 31, 2021		5,938,545
Balance at the beginning at Dec. 31, 2020	$ 420,989						$ 420,989
Balance at the beginning (in shares) at Dec. 31, 2020	69,613,562						69,613,562
Balance at the end (in shares) at Sep. 30, 2021							0
Balance at the beginning at Dec. 31, 2020		$ 1	37,778		(388,096)		$ (350,317)
Balance at the beginning (in shares) at Dec. 31, 2020		5,822,396
Equity
Proceeds from the exercise of stock options (in shares)							188,006
Net loss							$ (69,062)
Balance at the end at Sep. 30, 2021		$ 10	533,009		(457,158)		75,861
Balance at the end (in shares) at Sep. 30, 2021		103,003,384
Balance at the beginning at Mar. 31, 2021	$ 420,989
Balance at the beginning (in shares) at Mar. 31, 2021	69,613,562
Balance at the end at Jun. 30, 2021	$ 420,989
Balance at the end (in shares) at Jun. 30, 2021	69,613,562
Balance at the beginning at Mar. 31, 2021		$ 1	42,872		(408,397)		(365,524)
Balance at the beginning (in shares) at Mar. 31, 2021		5,938,545
Equity
Proceeds from the exercise of stock options			30				30
Proceeds from the exercise of stock options (in shares)		5,204
Net loss					(17,198)		(17,198)
Stock-based compensation			2,930				2,930
Balance at the end at Jun. 30, 2021		$ 1	45,832		(425,595)		$ (379,762)
Balance at the end (in shares) at Jun. 30, 2021		5,943,749
Redeemable convertible preferred Stock
Conversion of redeemable convertible preferred stock into common stock in connection with the Merger and related PIPE financing	$ (420,989)
Conversion of redeemable convertible preferred stock into common stock in connection with the Merger and related PIPE financing (in shares)	(69,613,562)
Balance at the end (in shares) at Sep. 30, 2021							0
Equity
Proceeds from the exercise of stock options			360				$ 360
Proceeds from the exercise of stock options (in shares)		99,624
Conversion of redeemable convertible preferred stock into common stock in connection with the Merger and related PIPE financing		$ 7	420,982				420,989
Conversion of redeemable convertible preferred stock into common stock in connection with the Merger and related PIPE financing (in shares)		69,613,562
The merger and related PIPE financing, net of transaction costs and acquired liabilities		$ 2	209,478				209,480
Public warrants assumed upon the merger, net of transaction costs			13,912				13,912
Issuance of common stock upon the Merger and related PIPE Financing, net of issuance costs (in shares)		27,346,449
Net loss					(31,563)		(31,563)
Stock-based compensation			1,877				1,877
Contingent consideration liability recognized upon closing of the reverse recapitalization			159,432				159,432
Balance at the end at Sep. 30, 2021		$ 10	$ 533,009		$ (457,158)		$ 75,861
Balance at the end (in shares) at Sep. 30, 2021		103,003,384

Condensed Consolidated Statements of Cash Flows $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Cash flows from operating activities
Net loss	$ (69,062)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	4,650
Stock-based compensation expense	7,335
Change in fair value of contingent earnout liability	9,768
Change in fair value of common stock warrant liabilities	2
Amortization expense	1,545
Non-cash operating lease costs	31
Amortization of SVB debt discount	628
Accrued interest on PPP loan obligation	11
Gain on PPP loan forgiveness	(3,284)
Payment of liabilities acquired in Merger	(12,363)
Changes in operating assets and liabilities:
Accounts receivable	(127)
Prepaid expenses	(2,002)
Accounts payable	757
Accrued expenses	2,401
Operating lease obligation	(32)
Net cash used in operating activities	(59,742)
Cash flows from investing activities
Purchase of property and equipment	(175)
Net cash used in investing activities	(175)
Cash flows from financing activities
Proceeds from merger	242,400
Payment of transaction costs related to Merger	(941)
Proceeds from the exercise of stock options	596
Proceeds from SVB loan	19,659
Payment of finance lease principal	(1,277)
Net cash provided by financing activities	260,437
Net increase (decrease) in cash and cash equivalents	200,520
Cash and cash equivalents at the beginning of the period	39,929
Cash and cash equivalents at the end of the period	240,449
Supplemental disclosure
Cash paid for interest on SVB loan	642
Supplemental disclosure of noncash activities:
Issuance of warrants in conjunction with debt	2,360
Unpaid liabilities assumed in connection with Merger	2,228
Unpaid transaction costs in connection with Merger	3,004
Conversion of redeemable convertible preferred stock into common stock in connection with the reverse capitalization	420,989
Contingent Consideration Liability recognized upon the closing of the reverse recapitalization	$ 159,432

Organization and Description of Business

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Organization and Description of Business

1. Organization and Description of Business

Organization

Refer to Note 3 — Reverse Recapitalization for further details of the Merger.

Liquidity and Going Concern

Impact of COVID-19

1. Organization and Description of Business

Organization

Liquidity and Going Concern

Since its inception in 2004, the Company has generated no product revenue and has incurred net losses and negative cash flows from operations in each year. To date, the Company has financed its operations primarily through the sale of equity securities and convertible debt and, to a lesser extent, through governmental and other grants. At December 31, 2019 and December 31, 2020, the Company had an accumulated deficit of $321.6 million and $388.1 million, respectively. The Company’s net losses were $85.4 million and $66.5 million for the years ended December 31, 2019 and 2020, respectively. Substantially all of the Company’s net losses resulted from costs incurred in connection with the Company’s research and development programs and from general and administrative costs associated with the Company’s operations. The Company expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future as the Company advances its product candidates.

Impact of COVID-19

1. Organization and Description of Business (continued)

Summary of Significant Accounting Policies

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

Unless otherwise noted, the Company has retroactively adjusted all common and preferred share and related price information to give effect to the Exchange Ratio established in the Merger Agreement.

Use of Estimates

Unaudited Interim Condensed Consolidated Financial Statements

Common Stock Warrants

Contingent Earnout Liability

Segments

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

Grant Revenue

Concentration of Credit Risk


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the three and nine months ended September 30, 2020 and 2021.

Other Risks and Uncertainties

Net Loss per Share Attributable to Common Stockholders


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204

Impairment of Long-Lived Assets

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP.

Reverse Recapitalization

On August 26, 2021 (the “Closing Date”), Alpha Healthcare Acquisition Corp. (“AHAC”) consummated a merger pursuant to which Hunter Merger Sub, Inc. (“Merger Sub”), a Delaware corporation and wholly owned subsidiary of AHAC, merged with Humacyte, Inc., a Delaware Corporation (“Legacy Humacyte”), with Legacy Humacyte surviving the Merger as a wholly-owned subsidiary of AHAC (such transactions, the “Merger,” and, collectively with the other transactions described in the Business Combination Agreement dated as of February 17, 2021 by and among Legacy Humacyte, Merger Sub, and AHAC (the “Merger Agreement”), the “Reverse Recapitalization”). As a result of the Merger, AHAC was renamed Humacyte, Inc. (“New Humacyte”) and Legacy Humacyte was renamed Humacyte Global, Inc.

Segments

Comprehensive loss

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in the financial statements include stock-based compensation costs, right-of-use, or ROU assets, accruals for research and development activities, fair value of common stock, useful lives of property and equipment, redeemable convertible preferred stock and income taxes. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

2. Summary of Significant Accounting Policies (continued)

Cash and Cash Equivalents

Redeemable Convertible Preferred Stock

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

2. Summary of Significant Accounting Policies (continued)

Grant Revenue

The Company recognizes funding received from grants as revenue, rather than as a reduction of research and development expenses, because the Company is the principal in conducting the research and development activities and these grants are central to the Company’s ongoing operations. The Company recognizes revenue only after the qualifying expenses related to the grants have been incurred and it is reasonably assured that the expenses will be reimbursed and the revenue will be collectible. The related costs incurred are included in research and development expense in our statements of operations and comprehensive loss.

Revenue from grants not within the scope of ASC 606 was $6.2 million and $1.5 million for the years ending December 31, 2019 and 2020, respectively.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. Total cash balances exceeded insured balances by the Federal Depository Insurance Corporation as of December 31, 2019 and 2020. Cash equivalents are invested in highly rated money market funds invested only in obligations of the US government and its agencies.


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the years ended December 31, 2019 and 2020.

2. Summary of Significant Accounting Policies (continued)

Other Risks and Uncertainties

Net Loss per Share Attributable to Common Stockholders

2. Summary of Significant Accounting Policies (continued)

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless inclusion of such shares would be anti-dilutive. Since the Company has only incurred losses, basic and diluted net loss per share is the same. Securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share are as follows:


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Fair Value of Financial Instruments

●

Level 1—Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets.

●

Level 3—Unobservable inputs in which little or no market data exists, therefore requiring the Company to develop its own assumptions.

2. Summary of Significant Accounting Policies (continued)

Property and Equipment, Net


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Impairment of Long-Lived Assets

The Company reviews the carrying value of property and equipment for indicators of possible impairment whenever events and circumstances indicate that the carrying value of an asset or asset group may not be recoverable from the estimated future net undiscounted cash flows expected to result from its use and eventual disposition. In cases where estimated future net undiscounted cash flows are less than the carrying value, an impairment loss is recognized equal to an amount by which the carrying value exceeds the fair value of the asset or asset group. The factors considered by management in performing this assessment include current operating results, trends and prospects, the manner in which the property is used, and the effects of obsolescence, demand, competition, and other economic factors. Based on this assessment, there was no impairment at December 31, 2019 and 2020.

Income Taxes

2. Summary of Significant Accounting Policies (continued)

Intellectual Property

Research and Development

The Company expenses research and development costs as operating expenses as incurred. Research and development expenses consist primarily of:

●

salaries and related overhead expenses for personnel in research and development functions, including stock-based compensation and benefits;

●

allocation of facility lease and maintenance costs;

●

depreciation of leasehold improvements, laboratory equipment and computers;

●

costs related to purchasing raw materials for and producing product candidates for clinical trials;

●

costs related to compliance with regulatory requirements;

●

costs related to the manufacturing scale-out initiative; and

●

license fees related to in-licensed technologies.

2. Summary of Significant Accounting Policies (continued)

Accrued Research and Development

Stock-Based Compensation

Leases

2. Summary of Significant Accounting Policies (continued)

The cumulative effect of initially applying the new lease guidance on January 1, 2019 is as follows:


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

2. Summary of Significant Accounting Policies (continued)

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

Reverse Recapitalization

9 Months Ended

Sep. 30, 2021

Reverse Recapitalization

Reverse Recapitalization

3. Reverse Recapitalization

On August 26, 2021, Merger Sub, a wholly-owned subsidiary of AHAC, merged with Legacy Humacyte, with Legacy Humacyte surviving as a wholly-owned subsidiary of AHAC. At the effective time of the Merger:

●

each outstanding share of Legacy Humacyte common stock was converted into approximately 0.26260 shares of the Company’s common stock;

●

each outstanding share of preferred stock of Legacy Humacyte was cancelled and converted into the aggregate number of shares of New Humacyte’s common stock that would be issued upon conversion of the shares of Legacy Humacyte preferred stock based on the applicable conversion ratio immediately prior to the effective time, multiplied by approximately 0.26260; and

●

each outstanding option or warrant to purchase Legacy Humacyte common stock was converted into an option or warrant, as applicable, to purchase a number of shares of the Company’s common stock equal to the number of shares of Legacy Humacyte common stock subject to such option or warrant multiplied by approximately 0.26260, at an exercise price per share equal to the current exercise price per share for such option or warrant divided by approximately 0.26260;

in each case, rounded down to the nearest whole share.

In addition, upon the closing of the merger (the “Closing”), 2,500,000 Class B shares of AHAC (Founder Shares) automatically converted into shares of the Company’s common stock, on a one-for-one basis.

Former holders of the Legacy Humacyte common stock and Legacy Humacyte preferred stock are eligible to receive up to an aggregate of 15 million additional shares of the Company’s common stock (the “Contingent Earnout Shares”) in the aggregate in two equal tranches of 7.5 million shares if the volume-weighted average closing sale price of the common stock is greater than or equal to $15.00 and $20.00, respectively, for any 20 trading days within any 30 consecutive trading day period. At the Closing on August 26, 2021, the Company recorded a liability (“Contingent Earnout Liability”) of $159.4 million, based on the estimated fair value of the 15 million Contingent Earnout Shares with a corresponding reduction of additional paid-in capital in the equity section of the Company’s condensed consolidated balance sheet.

Concurrently with the execution of the Business Combination Agreement, AHAC entered into subscription agreements (the “Subscription Agreements”) with certain investors (the “PIPE Investors”). Pursuant to the Subscription Agreements, the PIPE Investors purchased an aggregate of 17,500,000 shares of the Company’s common stock (the “PIPE Shares”) in a private placement at a price of $10.00 per share for an aggregate purchase price of $175 million (the “PIPE Financing”). The PIPE Financing was consummated in connection with the Closing.

The number of shares of the Company’s common stock outstanding immediately following the consummation of the Merger was:


	Shares
Common stock of AHAC, outstanding prior to Merger	10,355,000
Less redemption of AHAC shares	(3,008,551)
Common stock of AHAC	7,346,449
AHAC Founder Shares	2,500,000
New Humacyte shares issued to PIPE Investors	17,500,000
Issuance of common stock upon reverse recapitalization and PIPE Financing	27,346,449
New Humacyte shares issued in Merger to Legacy Humacyte stockholders	75,656,935	⁽¹⁾
Total shares of common stock immediately after Merger	103,003,384

(1) Includes 69,613,562 shares of common stock issued upon conversion of Legacy Humacyte’s redeemable convertible preferred stock.

The Merger is accounted for as a reverse recapitalization in accordance with U.S. GAAP. Under this method of accounting, AHAC is treated as the acquired company for financial reporting purposes and Legacy Humacyte is treated as the acquiror. This determination is primarily based on the fact that subsequent to the Merger, the Legacy Humacyte stockholders hold a majority of the voting rights of the combined company, Legacy Humacyte comprises all of the ongoing operations of the combined company, Legacy Humacyte comprises a majority of the carryover governing body of the combined company, and Legacy Humacyte’s senior management comprises all of the senior management of the combined company. Accordingly, for accounting purposes, the Merger was treated as the equivalent of Legacy Humacyte issuing shares for the net assets of AHAC, accompanied by a recapitalization. The net assets of AHAC were stated at historical costs. No goodwill or other intangible assets were recorded. Operations prior to the Merger are those of Legacy Humacyte.

In connection with the Merger, the Company received $242.4 million in proceeds from the Merger and related PIPE Financing. The Company incurred $3.9 million of transaction costs, consisting of banking, legal, and other professional fees, of which $3.9 million was recorded as a reduction of proceeds to additional paid-in capital, and less than $0.1 million related to the Private Placement Warrants, which are classified as liabilities in the condensed consolidated balance sheets, was expensed in the condensed consolidated statements of operations and comprehensive loss. Legacy Humacyte assumed $15.2 million of liabilities, including PIPE Financing fees and legal fees, and $0.1 million of assets from AHAC. Of the $15.2 million of liabilities assumed from AHAC, as of September 30, 2021, $2.2 million was included in accounts payable and accrued expenses. In addition, there were $3.0 million of unpaid transaction costs included in accounts payable and accrued expenses as of September 30, 2021.

Fair Value Measurements

9 Months Ended

Sep. 30, 2021

Fair Value Measurements

Fair Value Measurements

4. Fair Value Measurements

●

Level 1 — Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets.

●

Level 2 — Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

●

Level 3 — Unobservable inputs in which little or no market data exists, therefore requiring the Company to develop its own assumptions.

The Company’s assets and liabilities that were measured at fair value on a recurring basis were as follows:


	Fair Value Measured as of December 31, 2020
($in thousands)	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	35,623	$	—	$	—	$	35,623
Total financial assets	$	35,623	$	—	$	—	$	35,623


	Fair Value Measured as of September 30, 2021
($in thousands)	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	238,375	$	—	$	—	$	238,375
Total financial assets	$	238,375	$	—	$	—	$	238,375
Liabilities:
Contingent earnout liability	$	—	$	—	$	169,200	$	169,200
Common stock warrant liabilities (Private Placement Warrants)		—		—		555		555
Total financial liabilities	$	—	$	—	$	169,755	$	169,755

The following table presents a summary of the changes in the fair value of the Company’s Level 3 financial instruments:


	Contingent		Private Placement
($in thousands)	Earnout Liability		Warrants

Fair value as of December 31, 2020	$	—	$	—
Private placement warrant liability acquired as part of the merger		—		(553)
Contingent earount liability recognized upon the closing of the reverse recapitalization		(159,432)		—
Change in fair value included in other (expense) income		(9,768)		(2)
Fair value as of September 30, 2021	$	(169,200)	$	(555)

The fair value of the Contingent Earnout Liability and Private Placement Warrants liability are based on significant unobservable inputs, which represent Level 3 measurements within the fair value hierarchy.

In determining the fair value of the Contingent Earnout Liability, the Company used the Monte Carlo simulation value model using a distribution of potential outcomes on a monthly basis over a ten-year period prioritizing the most reliable information available. The assumptions utilized in the calculation were based on the achievement of certain stock price milestones, including the current Company common stock price, expected volatility, risk-free rate, expected term and expected dividend yield (see Note 8).

In determining the fair value of the Private Placement Warrants liability, the Company used the Monte Carlo simulation valuation model to estimate the fair value utilizing assumption including the current Company stock price, expected volatility, risk-free rate, expected term and expected dividend yield (see Note 8).

The Company’s cash equivalents are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. The carrying values of other receivables, accounts payable and accrued expenses as of December 31, 2020 and September 30, 2021 approximated their fair values due to the short-term nature of these items.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Property and Equipment, Net

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

5. Property and Equipment, Net

Property and equipment, net consist of the following:


	December 31,		September 30,
($ in thousands)	2020		2021

Scientific equipment	$	27,412	$	27,578
Computer equipment		149		154
Software		335		335
Furniture and fixtures		988		988
Leasehold improvements		26,355		26,355
		55,239		55,410
Accumulated depreciation		(14,261)		(18,911)
Property and equipment, net	$	40,978	$	36,499

3. Property and Equipment, Net

Property and equipment, net consist of the following:


	As of December 31,
($ in thousands)	2019		2020

Scientific equipment	$	27,822	$	27,412
Computer equipment		218		149
Software		340		335
Furniture and fixtures		988		988
Leasehold improvements		26,337		26,355
		55,705		55,239
Accumulated depreciation		(8,417)		(14,261)
Property and equipment, net	$	47,288	$	40,978

Depreciation expense totaled $4.7 million and $6.3 million for the years ended December 31, 2019 and 2020, respectively. All long-lived assets are maintained in the United States.

Accrued Expenses

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Accrued Expenses

6. Accrued Expenses

Accrued expenses consisted of the following:


	December 31,		September 30,
($ in thousands)	2020		2021

Accrued external research, development and manufacturing costs	$	2,615	$	2,685
Accrued employee compensation and benefits		1,009		4,025
Accrued professional fees		968		2,712
Total	$	4,592	$	9,422

4. Accrued Expenses

Accrued expenses consisted of the following:


	As of December 31,
($ in thousands)	2019		2020
Accrued external research, development and manufacturing costs	$	3,872	$	2,615
Accrued employee compensation and benefits		1,260		1,009
Accrued professional fees		868		968
Total	$	6,000	$	4,592

Debt

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Debt

Debt

7. Debt

SVB loan payable and net discount or premium balances are as follows:


	September 30,
($ in thousands)	2021
Principal amount of SVB loan payable	$	20,000
Final payment amount of SVB loan payable		1,000
Net premium associated with accretion of final payment and other debt issuance costs		(3,073)
SVB loan payable, current and noncurrent		17,927
Less SVB loan payable, current portion		(3,889)
SVB loan payable, noncurrent portion	$	14,038

Future minimum payments of principal on the Company’s outstanding variable rate borrowings as of September 30, 2021 are as follows:


Year ending December 31:	($ in thousands)
2021 (remainder)	$	—
2022		5,555
2023		6,667
2024		6,667
2025		1,111
Total future payments		20,000

5. Debt

Stockholders' Equity (Deficit)

Stockholders, Equity (Deficit)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Stockholders' Equity (Deficit)

8. Stockholders’ Equity (Deficit)

Redeemable Convertible Preferred Stock

Common Stock

The holders of common stock are entitled to receive dividends from time to time as may be declared by the Company’s board of directors. Through September 30, 2021, no dividends have been declared.

The holders of common stock are entitled to one vote for each share held with respect to all matters voted on by the common stockholders of the Company.

As of September 30, 2021, the Company had reserved common stock for future issuances as follows:


		September 30,
		2021
Common stock reserved for Contingent Consideration Shares		15,000,000
Exercise of options under stock plans		6,399,888
Issuance of options under stock plans		7,730,503
Shares available for grant under ESPP		1,030,033
Warrants to purchase common stock		5,465,204
		35,625,628

Preferred Stock

Warrants

Activity of warrants for the nine months ended September 30, 2021 is set forth below:


	Legacy
	Humacyte
	Common Stock	Private Placement		Total Common
	Warrants	Warrants	Public Warrants	Stock Warrants

Outstanding as of December 31, 2020	32,961	—	—	32,961
Common Stock Warrants issued to SVB	287,704	—	—	287,704
Common Stock Warrants as Part of the Merger	—	177,500	5,000,000	5,177,500
Warrants Exercised	(32,961)	—	—	(32,961)
Oustanding as of September 30, 2021	287,704	177,500	5,000,000	5,465,204

See Note 7 — Debt for a discussion of warrants issued in conjunction with the Company’s Loan Agreement.

Private Placement Warrants

The Private Placement Warrants were valued using the following assumptions under the Monte Carlo simulation value model:


	August 26,			September 30,
	2021			2021
Market price of public stock	$	10.96		$	11.61
Exercise price	$	11.50		$	11.50
Expected term (years)		5.00			4.91
Expected share price volatility		32.5	%		28.5	%
Risk-free interest rate		0.68	%		0.96	%
Estimated dividend yield		0	%		0	%

Public Warrants

Contingent Earnout Liability

Assumptions used in the valuations are described below:


	August 26,			September 30,
	2021			2021
Current stock price	$	10.96		$	11.61
Expected share price volatility		79.6	%		78.9	%
Risk-free interest rate		1.34	%		1.55	%
Estimated dividend yield		0	%		0.0	%
Expected term (years)		10.00			10.00

8. Stockholders’ Deficit

Common Stock

8. Stockholders’ Deficit (continued)

At December 31, 2019 and 2020, the Company had reserved common stock for future issuances as follows:


	December 31,
	2019	2020

Conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Conversion of Series C redeemable convertible preferred stock	11,241,286	11,241,286
Conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Exercise of options under stock plan	5,220,236	4,813,262
Issuance of options under stock plan	2,736,954	2,948,598
Warrant to purchase common stock	32,961	32,961
	77,603,716	77,408,386

Warrant

In conjunction with a long-term debt agreement entered into on March 15, 2006 and paid in full during 2011, the Company issued a warrant that gave the holder the right to purchase 32,961 shares of the Company’s common stock at an exercise price of $1.14 per share, which was outstanding as of December 31, 2019 and 2020. The warrant is exercisable and expires on March 15, 2021. There was no activity for the warrant during the years ended December 31, 2019 and 2020.

Stock-based Compensation

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Stock-based Compensation

9. Stock-based Compensation

The Company estimated the fair value of the stock options on the date of grant using the following assumptions in the Black-Scholes option-pricing model:


	Three Months Ended September 30,			Nine Months Ended September 30,
	2020		2021⁽¹⁾	2020		2021
Estimated dividend yield	0	%	—	0	%	0	%
Expected share price volatility (weighted average and range, if applicable)	91.6	%	—	91.4% (89.4% to 91.6%)		91.4% (91.0% to 92.1%)
Risk-free interest rate (weighted average and range, if applicable)	0.34	%	—	0.40% (0.34% to 0.75%)		0.68% (0.62% to 1.02%)
Expected term of options (in years)	6.0		—	6.0		6.0

(1)	The Company did not grant any stock options during the three months ended September 30, 2021.

●

Risk-Free Interest Rate. The risk-free interest rate was based on the yields of U.S. Treasury zero-coupon securities with maturities similar in duration to the expected term of the options.

●


	Three Months Ended September 30,				Nine Months Ended September 30,
($ in thousands)	2020		2021		2020		2021
Research and development	$	308	$	486	$	781	$	1,837
General and administrative		862		1,391		2,685		5,498
Total	$	1,170	$	1,877	$	3,466	$	7,335


	December 31,		September 30,
($ in thousands)	2020		2021
Unrecognized share-based compensation cost	$	5,789	$	12,480
Expected weighted average period compensation costs to be recognized (years)		1.7		2.1

A summary of option activity under the Company’s stock option plans during the nine months ended September 30, 2021 is presented below:


				Weighted
				Average
		Weighted		Remaining	Aggregate
		Average Exercise		Contractual Term	Intrinsic Value
	Number of Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Granted	1,838,029	$	10.28
Exercised	(188,006)	$	2.97
Forfeited	(63,397)	$	7.87
Options outstanding at September 30, 2021	6,399,888	$	7.33	6.6	$	26,705
Vested and exercisable, September 30, 2021	4,092,342	$	5.74	5.1	$	23,345
Vested and expected to vest, September 30, 2021	6,399,888	$	7.33	6.6	$	26,705

The Company did not grant any stock options during the three months ended September 30, 2021.

9. Stock-based Compensation

9. Stock-based Compensation (continued)

The Company used the following assumptions on the date of grant to estimate the fair value of the stock options in the Black-Scholes option-pricing model as follows:


	Year Ended December 31,
	2019		2020
Estimated dividend yield	0	%	0	%
Expected share price volatility	70.1%-87.7	%	89.4% - 91.6	%
Risk-free interest rate	1.76% - 2.46	%	0.34% - 0.75	%
Expected term of options (in years)	6.00		6.00

●

Risk-Free Interest Rate. The risk-free interest rate was based on the yields of US Treasury zero-coupon securities with maturities similar in duration to the expected term of the options.

●

9. Stock-based Compensation (continued)


	Year Ended December 31,
($ in thousands)	2019		2020
Research and development	$	914	$	1,135
General and administrative		3,543		3,559
Total	$	4,457	$	4,694


	As of December 31,
($ in thousands)	2019		2020
Unrecognized share-based compensation cost	$	7,919	$	5,789
Expected weighted average period compensation costs to be recognized (years)		1.8		1.7

A summary of option activity under the 2015 Plan during the years ended December 31, 2019 and 2020 is presented below:


				Weighted
				Average
		Weighted		Remaining	Aggregate
	Number of	Average Exercise		Contractual Term	Intrinsic Value
	Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2018	5,638,773	$	4.69	7.4	$	21,354
Granted	621,031		8.49
Exercised	(620,831)		1.97
Forfeited	(418,737)		7.62
Options outstanding at December 31, 2019	5,220,236	$	5.22	6.5	$	17,044
Granted	480,856		9.79
Exercised	(195,239)		1.55
Forfeited	(692,591)		3.76
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Vested and exercisable, December 31, 2020	3,392,302	$	4.99	5.9	$	17,925
Vested and expected to vest, December 31, 2020	4,813,262	$	6.04	6.6	$	20,422

The total intrinsic value of options exercised during the years ended December 31, 2019 and 2020 was $4.0 million and $1.4 million, respectively.

The weighted-average grant-date fair value per share of options granted during the years ended December 31, 2019 and 2020 was $5.84 and $7.26, respectively.

Income Taxes

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

10. Income Taxes


	As of December 31,
($ in thousands)	2019		2020
Deferred tax assets:
Net operating loss	$	50,616	$	53,515
Capitalized research and development		19,660		32,337
Research credits		10,658		15,056
Share-based compensation		1,669		2,519
Right of use lease liability		207		177
Accrued expenses		71		57
Other		1		1
Total deferred tax asset		82,882		103,662
Less: valuation allowance		(82,193)		(101,757)
Total net deferred tax asset		689		1,905

Deferred tax liabilities:
Basis difference in fixed assets		(482)		(1,728)
Right of use lease assets		(207)		(177)
Total deferred tax liability		(689)		(1,905)
Total net deferred tax asset/(liability)	$	—	$	—

10. Income Taxes (continued)


	December 31,
	2019				2020
($ in thousands)	Amount		Rate		Amount		Rate
Income tax benefit at statutory rate	$	(17,939)	21.0	%	$	(13,970)	21.0	%
State income taxes, net of federal benefit		(1,739)	2.0	%		(1,338)	2.0	%
Tax credits		(1,821)	2.1	%		(2,625)	3.9	%
Other nondeductible expenses		54	0.0	%		90	(0.1)	%
Deferred rate changes		16	0.0	%		16	0.0	%
Other		449	(0.5)	%		(1,736)	2.6	%
Change in valuation allowance		20,980	(24.6)	%		19,563	(29.4)	%
Provision for income taxes	$	—	0.0	%	$	—	0.0	%

Commitments and Contingencies

Commitments and Contingencies

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Commitments and Contingencies

11. Commitments and Contingencies

Patent License Agreements

Duke University

●

a low single-digit percentage royalty on eligible sales of licensed products and licensed services, plus a low double-digit percentage of any sublicensing revenue;

●

an additional amount in license fees, as certain milestones are met.

Yale University

fee, increasing between the first and fourth anniversaries of the agreement up to a maximum of less than $0.1 million per year for this license.

In connection with its entry into the license agreement, the Company paid Yale upfront cash fees. The Company has also agreed to pay Yale:

●

milestone payments upon achievement of certain regulatory and commercial milestones of $0.2 million and $0.6 million;

●

a low single-digit percentage royalty on worldwide net sales, subject to reductions for third-party license fees; and

●

a low double-digit percentage of sublicensing income.

Legal Matters

Indemnification

12. Commitments and Contingencies

Patent License Agreements

Duke University

●

a low single-digit percentage royalty on eligible sales of licensed products and licensed services, plus a low double-digit percentage of any sublicensing revenue;

●

an additional amount in license fees, as certain milestones are met.

12. Commitments and Contingencies (continued)

Yale University

In February 2014, the Company entered into a license agreement with Yale University, or Yale, that granted the Company a worldwide license to the patents related to coatings for small-diameter vessels to inhibit clotting. The license granted under the agreement is exclusive in the field of engineered vascular tissues and tissues and extracellular matrix-based implants used for vascular repair, reconstruction and replacement (provided that all uses are vascular tissues within the range of 1–12mm in diameter), except that it is subject to Yale’s non-exclusive right, on behalf of itself and all other non-profit academic institutions, to use the licensed products for research, teaching, and other non-commercial purposes.

In connection with its entry into the license agreement, the Company paid Yale upfront cash fees. The Company has also agreed to pay Yale:

●

milestone payments upon achievement of certain regulatory and commercial milestones;

●

a low single-digit percentage royalty on worldwide net sales, subject to reductions for third-party license fees; and

●

a low double-digit percentage of sublicensing income.

12. Commitments and Contingencies (continued)

Legal Matters

Indemnification

To the extent permitted under Delaware law, the Company has agreed to indemnify its directors and officers for certain events or occurrences while the director or officer is, or was serving, at the Company’s request in such capacity. The indemnification period covers all pertinent events and occurrences during the director’s or officer’s service. The maximum potential amount of future payments the Company could be required to make under these indemnification arrangements is not specified in such arrangements; however, the Company has director and officer insurance coverage that is intended to reduce its exposure and enable the Company to recover a portion of any future amounts paid. The Company believes the estimated fair value of these indemnification arrangements in excess of applicable insurance coverage is immaterial.

Related Party Transactions

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Related Party Transactions

12. Related Party Transactions

Fresenius Medical Care investments and distribution agreement

Arrangements with Dr. Niklason and Yale University

The following table shows a summary of related party expenses included in the statements of operations and comprehensive loss for the three and nine months ended September 30, 2020 and 2021:


	Three Months Ended September 30,		Nine Months Ended September 30,
($ in thousands)	2020	2021	2020	2021
Expenses under MOU	125	—	375	—
License expenses	20	—	70	85
Other	4	2	17	83
Total	149	2	462	168

As of December 31, 2020 and September 30, 2021, the Company was a party to license agreements with Yale University, as described in Note 11 — Commitments and Contingencies, above.

13. Related Party Transactions

Fresenius Medical Care distribution agreement

13. Related Party Transactions (continued)

Arrangements with Dr. Niklason and Yale University

The MOU provided for the Company to make a payment each year through 2023 to the academic institution with which Dr. Niklason was then affiliated, up to an aggregate amount of $2.5 million for 2018 through 2023, and to pay Dr. Niklason reasonable consulting fees in consideration of the services she performed for the Company. For the years ended December 31, 2019 and 2020, the company made payments under the MOU of $0.4 million and $0.5 million, respectively, to, or on behalf of, Yale University, where Dr. Niklason, currently the Company’s President, CEO and a member of the Company’s board of directors, serves as a Professor Adjunct, Division Chief and Vice Chair, Research in Anesthesia. The MOU was terminated effective November 9, 2020.

The following table shows a summary of related party expenses included in the statements of operations and comprehensive loss for the years ended December 31, 2019 and 2020:


	Year Ended
	December 31,
($ in thousands)	2019		2020
Expenses under MOU	$	422	$	500
License expenses		110		92
Other		39		28
Total	$	571	$	620

As of December 31, 2019 and December 31, 2020, the Company was a party to license agreements with Yale University, as described in Note 12 — Commitments and Contingencies above.

Subsequent Events

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Subsequent Events [Abstract]

Subsequent Events

13. Subsequent Events

14. Subsequent Events

The Company evaluated the effect subsequent events would have on the financial statements through March 22, 2021, which is the date the financial statements were issued.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Unaudited Interim Condensed Consolidated Financial Statements

Basis of Presentation

Basis of Presentation

Unless otherwise noted, the Company has retroactively adjusted all common and preferred share and related price information to give effect to the Exchange Ratio established in the Merger Agreement.

Basis of Presentation

The Company has prepared the accompanying financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP.

Reverse Recapitalization

Unaudited Interim Condensed Consolidated Financial Statements

On August 26, 2021 (the “Closing Date”), Alpha Healthcare Acquisition Corp. (“AHAC”) consummated a merger pursuant to which Hunter Merger Sub, Inc. (“Merger Sub”), a Delaware corporation and wholly owned subsidiary of AHAC, merged with Humacyte, Inc., a Delaware Corporation (“Legacy Humacyte”), with Legacy Humacyte surviving the Merger as a wholly-owned subsidiary of AHAC (such transactions, the “Merger,” and, collectively with the other transactions described in the Business Combination Agreement dated as of February 17, 2021 by and among Legacy Humacyte, Merger Sub, and AHAC (the “Merger Agreement”), the “Reverse Recapitalization”). As a result of the Merger, AHAC was renamed Humacyte, Inc. (“New Humacyte”) and Legacy Humacyte was renamed Humacyte Global, Inc.

Common Stock Warrants

Common Stock Warrants

Contingent Earnout Liability

Contingent Earnout Liability

Segments

Segments

Comprehensive loss

Comprehensive loss

Use of Estimates

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Significant estimates in the financial statements include stock-based compensation costs, right-of-use, or ROU assets, accruals for research and development activities, fair value of common stock, useful lives of property and equipment, redeemable convertible preferred stock and income taxes. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could differ from those estimates.

2. Summary of Significant Accounting Policies (continued)

Cash and Cash Equivalents

Cash and Cash Equivalents

Redeemable Convertible Preferred Stock

Redeemable Convertible Preferred Stock

Revenue Recognition

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

Revenue Recognition

The Company’s revenues generally consist of grant revenues, including revenues generated under government and other awarded grants.

In addition, ASC 606 requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

2. Summary of Significant Accounting Policies (continued)

Grant Revenue

The Company recognizes funding received from grants as revenue, rather than as a reduction of research and development expenses, because the Company is the principal in conducting the research and development activities and these grants are central to the Company’s ongoing operations. The Company recognizes revenue only after the qualifying expenses related to the grants have been incurred and it is reasonably assured that the expenses will be reimbursed and the revenue will be collectible. The related costs incurred are included in research and development expense in our statements of operations and comprehensive loss.

Revenue from grants not within the scope of ASC 606 was $6.2 million and $1.5 million for the years ending December 31, 2019 and 2020, respectively.

Concentration of Credit Risk

Concentration of Credit Risk


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the three and nine months ended September 30, 2020 and 2021.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. Total cash balances exceeded insured balances by the Federal Depository Insurance Corporation as of December 31, 2019 and 2020. Cash equivalents are invested in highly rated money market funds invested only in obligations of the US government and its agencies.


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

All of the Company’s revenues were generated from grants from government and other entities located in the United States, for the years ended December 31, 2019 and 2020.

Other Risks and Uncertainties

Other Risks and Uncertainties

2. Summary of Significant Accounting Policies (continued)

Other Risks and Uncertainties

Net Loss per Share Attributable to Common Stockholders

Net Loss per Share Attributable to Common Stockholders


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204

Net Loss per Share Attributable to Common Stockholders

2. Summary of Significant Accounting Policies (continued)

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period without consideration of potentially dilutive common stock. Diluted net loss per share attributable to common stockholders reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the Company unless inclusion of such shares would be anti-dilutive. Since the Company has only incurred losses, basic and diluted net loss per share is the same. Securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share are as follows:


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Fair Value of Financial Instruments

●

Level 1—Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets.

●

Level 3—Unobservable inputs in which little or no market data exists, therefore requiring the Company to develop its own assumptions.

2. Summary of Significant Accounting Policies (continued)

Fair Value of Financial Instruments


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Impairment of Long-Lived Assets

Property and Equipment, Net


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Impairment of Long-Lived Assets


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Accrued Research and Development

Income Taxes

2. Summary of Significant Accounting Policies (continued)

Intellectual Property

Intellectual Property

Research and Development

Research and Development

The Company expenses research and development costs as operating expenses as incurred. Research and development expenses consist primarily of:

●

salaries and related overhead expenses for personnel in research and development functions, including stock-based compensation and benefits;

●

allocation of facility lease and maintenance costs;

●

depreciation of leasehold improvements, laboratory equipment and computers;

●

costs related to purchasing raw materials for and producing product candidates for clinical trials;

●

costs related to compliance with regulatory requirements;

●

costs related to the manufacturing scale-out initiative; and

●

license fees related to in-licensed technologies.

Accrued Research and Development

Leases

Leases

2. Summary of Significant Accounting Policies (continued)

The cumulative effect of initially applying the new lease guidance on January 1, 2019 is as follows:


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements

Summary of Significant Accounting Policies (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of 10% or more of the Company's total revenue or accounts receivable balance


	Revenue								Accounts Receivable
	Three Months Ended September 30,				Nine Months Ended September 30,				December 31,		September 30,
	2020		2021		2020		2021		2020		2021
Grant A	—		—		—		—		—		—
Grant B	0		—	%	11		—	%	—		—
Grant C	68	%	100	%	65	%	100	%	100	%	100	%
Grant D	30		—	%	20		—	%	—		—
Total	98	%	100	%	96	%	100	%	100	%	100	%


	2019				2020
			Accounts				Accounts
	Revenue		Receivable		Revenue		Receivable
Grant A	28	%	—		—		—
Grant B	38	%	67	%	10	%	—
Grant C	34	%	33	%	67	%	100	%
Grant D	—		—		18	%	—
Total	100	%	100	%	95	%	100	%

Summary of securities that could potentially dilute net loss per share in the future that were not included in the computation of diluted net loss per share


	September 30,
	2020	2021

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	—
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	—
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	—
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	—
Exercise of options under stock plan	4,516,907	6,399,888
Warrants to purchase common stock	32,961	5,465,204


	December 31,
	2019	2020

Shares issuable upon conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Shares issuable upon conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Shares issuable upon conversion of Series C redeemable convertible preferred stock	11,241,283	11,241,283
Shares issuable upon conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Options to purchase common stock	5,220,236	4,813,262
Warrant to purchase common stock	32,961	32,961

Summary of estimated useful lives for significant asset


		Estimated Useful
Property and equipment		Lives (Years)
Scientific equipment		5 – 7
Computer equipment		5
Software		3
Furniture and fixtures		5 – 7
Leasehold improvements		Lesser of useful life or life of lease
Construction in progress		N/A

Summary of cumulative effect of initially applying the new lease guidance


	January 1, 2019
			Cumulative		Beginning
	Beginning		Effect		Balance,
($ in thousands)	Balance		Adjustment		As Adjusted
Assets
Building asset	$	25,091	$	(25,091)	$	—
Finance lease right-of-use assets, net	$	—	$	27,612	$	27,612
Operating lease right-of-use assets, net	$	—	$	923	$	923

Liabilities and stockholders’ deficit
Accrued expenses	$	7,049	$	(1)	$	7,048
Facility financing obligation, current portion	$	276	$	(276)	$	—
Finance lease obligation, current portion	$	—	$	1,292	$	1,292
Operating lease obligation, current portion	$	—	$	55	$	55
Facility financing obligation, net of current portion	$	22,955	$	(22,955)	$	—
Finance lease obligation, net of current portion	$	—	$	26,319	$	26,319
Operating lease obligation, net of current portion	$	—	$	870	$	870
Accumulated deficit	$	(234,289)	$	(1,861)	$	(236,150)

Reverse Recapitalization (Tables)

9 Months Ended

Sep. 30, 2021

Reverse Recapitalization

Schedule of common stock outstanding immediately following the consummation of the Merger


	Shares
Common stock of AHAC, outstanding prior to Merger	10,355,000
Less redemption of AHAC shares	(3,008,551)
Common stock of AHAC	7,346,449
AHAC Founder Shares	2,500,000
New Humacyte shares issued to PIPE Investors	17,500,000
Issuance of common stock upon reverse recapitalization and PIPE Financing	27,346,449
New Humacyte shares issued in Merger to Legacy Humacyte stockholders	75,656,935	⁽¹⁾
Total shares of common stock immediately after Merger	103,003,384

(1) Includes 69,613,562 shares of common stock issued upon conversion of Legacy Humacyte’s redeemable convertible preferred stock.

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2021

Fair Value Measurements

Schedule of assets and liabilities that were measured at fair value on a recurring basis


	Fair Value Measured as of September 30, 2021
($in thousands)	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	238,375	$	—	$	—	$	238,375
Total financial assets	$	238,375	$	—	$	—	$	238,375
Liabilities:
Contingent earnout liability	$	—	$	—	$	169,200	$	169,200
Common stock warrant liabilities (Private Placement Warrants)		—		—		555		555
Total financial liabilities	$	—	$	—	$	169,755	$	169,755

Summary of the changes in the fair value of the Company's Level 3 financial instruments


	Contingent		Private Placement
($in thousands)	Earnout Liability		Warrants

Fair value as of December 31, 2020	$	—	$	—
Private placement warrant liability acquired as part of the merger		—		(553)
Contingent earount liability recognized upon the closing of the reverse recapitalization		(159,432)		—
Change in fair value included in other (expense) income		(9,768)		(2)
Fair value as of September 30, 2021	$	(169,200)	$	(555)

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

Property and Equipment, Net (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Schedule of Property and equipment


	December 31,		September 30,
($ in thousands)	2020		2021

Scientific equipment	$	27,412	$	27,578
Computer equipment		149		154
Software		335		335
Furniture and fixtures		988		988
Leasehold improvements		26,355		26,355
		55,239		55,410
Accumulated depreciation		(14,261)		(18,911)
Property and equipment, net	$	40,978	$	36,499


	As of December 31,
($ in thousands)	2019		2020

Scientific equipment	$	27,822	$	27,412
Computer equipment		218		149
Software		340		335
Furniture and fixtures		988		988
Leasehold improvements		26,337		26,355
		55,705		55,239
Accumulated depreciation		(8,417)		(14,261)
Property and equipment, net	$	47,288	$	40,978

Accrued Expenses (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Schedule of Accrued Expenses


	December 31,		September 30,
($ in thousands)	2020		2021

Accrued external research, development and manufacturing costs	$	2,615	$	2,685
Accrued employee compensation and benefits		1,009		4,025
Accrued professional fees		968		2,712
Total	$	4,592	$	9,422


	As of December 31,
($ in thousands)	2019		2020
Accrued external research, development and manufacturing costs	$	3,872	$	2,615
Accrued employee compensation and benefits		1,260		1,009
Accrued professional fees		868		968
Total	$	6,000	$	4,592

Debt (Tables)

9 Months Ended

Sep. 30, 2021

Debt

Summary of SVB loan payable and net discount or premium balances


	September 30,
($ in thousands)	2021
Principal amount of SVB loan payable	$	20,000
Final payment amount of SVB loan payable		1,000
Net premium associated with accretion of final payment and other debt issuance costs		(3,073)
SVB loan payable, current and noncurrent		17,927
Less SVB loan payable, current portion		(3,889)
SVB loan payable, noncurrent portion	$	14,038

Summary of future minimum payments of principal and estimated payments of interest


Year ending December 31:	($ in thousands)
2021 (remainder)	$	—
2022		5,555
2023		6,667
2024		6,667
2025		1,111
Total future payments		20,000

Schedule of activity of warrants

Stockholders' Equity (Deficit) (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020


	Legacy
	Humacyte
	Common Stock	Private Placement		Total Common
	Warrants	Warrants	Public Warrants	Stock Warrants

Outstanding as of December 31, 2020	32,961	—	—	32,961
Common Stock Warrants issued to SVB	287,704	—	—	287,704
Common Stock Warrants as Part of the Merger	—	177,500	5,000,000	5,177,500
Warrants Exercised	(32,961)	—	—	(32,961)
Oustanding as of September 30, 2021	287,704	177,500	5,000,000	5,465,204

Summary of common stock reserved for future issuances


		September 30,
		2021
Common stock reserved for Contingent Consideration Shares		15,000,000
Exercise of options under stock plans		6,399,888
Issuance of options under stock plans		7,730,503
Shares available for grant under ESPP		1,030,033
Warrants to purchase common stock		5,465,204
		35,625,628


	December 31,
	2019	2020

Conversion of Series A redeemable convertible preferred stock	18,421,897	18,421,897
Conversion of Series B redeemable convertible preferred stock	24,137,647	24,137,647
Conversion of Series C redeemable convertible preferred stock	11,241,286	11,241,286
Conversion of Series D redeemable convertible preferred stock	15,812,735	15,812,735
Exercise of options under stock plan	5,220,236	4,813,262
Issuance of options under stock plan	2,736,954	2,948,598
Warrant to purchase common stock	32,961	32,961
	77,603,716	77,408,386

Private Placement Warrants

Contingent earnout liability


	August 26,			September 30,
	2021			2021
Market price of public stock	$	10.96		$	11.61
Exercise price	$	11.50		$	11.50
Expected term (years)		5.00			4.91
Expected share price volatility		32.5	%		28.5	%
Risk-free interest rate		0.68	%		0.96	%
Estimated dividend yield		0	%		0	%


	August 26,			September 30,
	2021			2021
Current stock price	$	10.96		$	11.61
Expected share price volatility		79.6	%		78.9	%
Risk-free interest rate		1.34	%		1.55	%
Estimated dividend yield		0	%		0.0	%
Expected term (years)		10.00			10.00

Stock-based Compensation (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020

Summary of assumptions on the date of grant to estimate the fair value of the stock options in the Black-Scholes option-pricing model


	Three Months Ended September 30,			Nine Months Ended September 30,
	2020		2021⁽¹⁾	2020		2021
Estimated dividend yield	0	%	—	0	%	0	%
Expected share price volatility (weighted average and range, if applicable)	91.6	%	—	91.4% (89.4% to 91.6%)		91.4% (91.0% to 92.1%)
Risk-free interest rate (weighted average and range, if applicable)	0.34	%	—	0.40% (0.34% to 0.75%)		0.68% (0.62% to 1.02%)
Expected term of options (in years)	6.0		—	6.0		6.0


	Year Ended December 31,
	2019		2020
Estimated dividend yield	0	%	0	%
Expected share price volatility	70.1%-87.7	%	89.4% - 91.6	%
Risk-free interest rate	1.76% - 2.46	%	0.34% - 0.75	%
Expected term of options (in years)	6.00		6.00

Summary of stock-based compensation expense included in the statements of operations and comprehensive loss


	Three Months Ended September 30,				Nine Months Ended September 30,
($ in thousands)	2020		2021		2020		2021
Research and development	$	308	$	486	$	781	$	1,837
General and administrative		862		1,391		2,685		5,498
Total	$	1,170	$	1,877	$	3,466	$	7,335


	December 31,		September 30,
($ in thousands)	2020		2021
Unrecognized share-based compensation cost	$	5,789	$	12,480
Expected weighted average period compensation costs to be recognized (years)		1.7		2.1


	Year Ended December 31,
($ in thousands)	2019		2020
Research and development	$	914	$	1,135
General and administrative		3,543		3,559
Total	$	4,457	$	4,694


	As of December 31,
($ in thousands)	2019		2020
Unrecognized share-based compensation cost	$	7,919	$	5,789
Expected weighted average period compensation costs to be recognized (years)		1.8		1.7

Summary of option activity


				Weighted
				Average
		Weighted		Remaining	Aggregate
		Average Exercise		Contractual Term	Intrinsic Value
	Number of Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Granted	1,838,029	$	10.28
Exercised	(188,006)	$	2.97
Forfeited	(63,397)	$	7.87
Options outstanding at September 30, 2021	6,399,888	$	7.33	6.6	$	26,705
Vested and exercisable, September 30, 2021	4,092,342	$	5.74	5.1	$	23,345
Vested and expected to vest, September 30, 2021	6,399,888	$	7.33	6.6	$	26,705


				Weighted
				Average
		Weighted		Remaining	Aggregate
	Number of	Average Exercise		Contractual Term	Intrinsic Value
	Shares	Price Per Share		(years)	(in thousands)
Options outstanding at December 31, 2018	5,638,773	$	4.69	7.4	$	21,354
Granted	621,031		8.49
Exercised	(620,831)		1.97
Forfeited	(418,737)		7.62
Options outstanding at December 31, 2019	5,220,236	$	5.22	6.5	$	17,044
Granted	480,856		9.79
Exercised	(195,239)		1.55
Forfeited	(692,591)		3.76
Options outstanding at December 31, 2020	4,813,262	$	6.04	6.6	$	20,422
Vested and exercisable, December 31, 2020	3,392,302	$	4.99	5.9	$	17,925
Vested and expected to vest, December 31, 2020	4,813,262	$	6.04	6.6	$	20,422

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Schedule of components of Company's deferred tax assets and deferred tax liabilities


	As of December 31,
($ in thousands)	2019		2020
Deferred tax assets:
Net operating loss	$	50,616	$	53,515
Capitalized research and development		19,660		32,337
Research credits		10,658		15,056
Share-based compensation		1,669		2,519
Right of use lease liability		207		177
Accrued expenses		71		57
Other		1		1
Total deferred tax asset		82,882		103,662
Less: valuation allowance		(82,193)		(101,757)
Total net deferred tax asset		689		1,905

Deferred tax liabilities:
Basis difference in fixed assets		(482)		(1,728)
Right of use lease assets		(207)		(177)
Total deferred tax liability		(689)		(1,905)
Total net deferred tax asset/(liability)	$	—	$	—

Schedule of difference between the actual income tax benefit and amount computed by applying the statutory Federal income tax rate to losses before income taxes


	December 31,
	2019				2020
($ in thousands)	Amount		Rate		Amount		Rate
Income tax benefit at statutory rate	$	(17,939)	21.0	%	$	(13,970)	21.0	%
State income taxes, net of federal benefit		(1,739)	2.0	%		(1,338)	2.0	%
Tax credits		(1,821)	2.1	%		(2,625)	3.9	%
Other nondeductible expenses		54	0.0	%		90	(0.1)	%
Deferred rate changes		16	0.0	%		16	0.0	%
Other		449	(0.5)	%		(1,736)	2.6	%
Change in valuation allowance		20,980	(24.6)	%		19,563	(29.4)	%
Provision for income taxes	$	—	0.0	%	$	—	0.0	%

Related Party Transactions (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2021

Dec. 31, 2020


	Three Months Ended September 30,		Nine Months Ended September 30,
($ in thousands)	2020	2021	2020	2021
Expenses under MOU	125	—	375	—
License expenses	20	—	70	85
Other	4	2	17	83
Total	149	2	462	168


	Year Ended
	December 31,
($ in thousands)	2019		2020
Expenses under MOU	$	422	$	500
License expenses		110		92
Other		39		28
Total	$	571	$	620

Organization and Description of Business (Details) - USD ($) $ in Thousands			3 Months Ended						9 Months Ended		12 Months Ended
	Aug. 26, 2021	Mar. 22, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Organization and Description of Business
Proceeds from merger	$ 242,400								$ 242,400
Accumulated deficit			$ 457,158						457,158		$ 388,096	$ 321,572	$ 234,289
Net loss			31,563	$ 17,198	$ 20,301	$ 17,760	$ 14,878	$ 17,674	69,062	$ 50,312	66,524	85,422
Cash and cash equivalents			$ 240,449						$ 240,449		$ 39,929	$ 93,713
Substantial Doubt about Going Concern, within One Year [true false]		true

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

The cumulative amount of the reporting entity's undistributed earnings or deficit.

Summary of Significant Accounting Policies - Common Stock Warrants (Details) - $ / shares	Aug. 26, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 15, 2006
Summary of Significant Accounting Policies
Public warrants assumed	5,000,000
Private placement warrants assumed	177,500
Common stock, par value	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Warrants, exercise price	$ 11.50				$ 1.14
Share accepting a tender offer entitles warrants to receive cash (as a percent)	50.00%

Summary of Significant Accounting Policies - Contingent Earnout Liability (Details)	Sep. 30, 2021	Aug. 26, 2021 tranche shares	Feb. 17, 2021 tranche shares
Summary of Significant Accounting Policies
Maximum contingent earnout shares		15,000,000	15,000,000
Number of tranches of contingent earnout shares \| tranche		2	2
Number of contingent earnout shares per tranche		7,500,000	7,500,000
Warrants term	10 years

Summary of Significant Accounting Policies (Details) - segment	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Segments
Exchange ratio					0.2626%
Number of reportable segment	1	1	1	1	1	1
Number of operating segment					1

Summary of Significant Accounting Policies - Grant Revenue (Details) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended		86 Months Ended
	Sep. 30, 2017	Aug. 31, 2017	Nov. 30, 2013	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from grants not within the scope of ASC 606				$ 200	$ 900	$ 1,100	$ 1,400	$ 1,500	$ 6,200	$ 1,600
Department of Defense grants \| Work on bioengineered blood vessels for vascular trauma
Disaggregation of Revenue [Line Items]
Grants	$ 4,000
Department of Defense grants \| Work to support human tissue engineered blood vessels for vascular reconstruction
Disaggregation of Revenue [Line Items]
Grants		$ 7,100
Department of Defense grants \| Reimbursement of certain allowable costs related to grants
Disaggregation of Revenue [Line Items]
Recognized revenue				200	600	1,100	1,000
National Institutes of Health grant \| Reimbursement of certain allowable costs related to grants
Disaggregation of Revenue [Line Items]
Recognized revenue				$ 0	$ 300	$ 0	$ 300
National Institutes of Health grant \| Work to support bioengineered grafts for peripheral vascular disease
Disaggregation of Revenue [Line Items]
Grants			$ 1,600

Summary of Significant Accounting Policies -Concentration of Credit Risk (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Revenue \| Customer concentration
Concentration Risk [Line Items]
Concentration of Credit Risk	100.00%	98.00%	100.00%	96.00%	95.00%	100.00%
Revenue \| Customer concentration \| Grant A
Concentration Risk [Line Items]
Concentration of Credit Risk						28.00%
Revenue \| Customer concentration \| Grant B
Concentration Risk [Line Items]
Concentration of Credit Risk		0.00%		11.00%	10.00%	38.00%
Revenue \| Customer concentration \| Grant C
Concentration Risk [Line Items]
Concentration of Credit Risk	100.00%	68.00%	100.00%	65.00%	67.00%	34.00%
Revenue \| Customer concentration \| Grant D
Concentration Risk [Line Items]
Concentration of Credit Risk		30.00%		20.00%	18.00%
Accounts Receivable \| Credit concentration
Concentration Risk [Line Items]
Concentration of Credit Risk			100.00%		100.00%	100.00%
Accounts Receivable \| Credit concentration \| Grant B
Concentration Risk [Line Items]
Concentration of Credit Risk						67.00%
Accounts Receivable \| Credit concentration \| Grant C
Concentration Risk [Line Items]
Concentration of Credit Risk			100.00%		100.00%	33.00%

Summary of Significant Accounting Policies - Net Loss per Share Attributable to Common Stockholders (Details) - shares	9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Contingent consideration (in shares)	15,000,000
Series A redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		18,421,897	18,421,897	18,421,897
Series B redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		24,137,647	24,137,647	24,137,647
Series C redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		11,241,283	11,241,283	11,241,283
Series D redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share		15,812,735	15,812,735	15,812,735
Exercise of options under stock plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share	6,399,888	4,516,907	4,813,262	5,220,236
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities that were not included in the computation of diluted net loss per share	5,465,204	32,961	32,961	32,961

Summary of Significant Accounting Policies - Property and Equipment, Net (Details)	12 Months Ended
	Dec. 31, 2020
Scientific equipment. \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Scientific equipment. \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Computer equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Software
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Furniture and fixtures \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Furniture and fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years

Summary of Significant Accounting Policies - Impairment of Long-Lived Assets and Income Taxes (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended		24 Months Ended
	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Impairment of Long-Lived Assets
Impairment of long-lived assets	$ 0	$ 0	$ 0
Income Taxes
Uncertain tax positions		0		$ 0
Accrued interest or penalties related to uncertain tax positions		$ 0		0
interest or penalties related to uncertain tax positions expensed				$ 0

Reverse Recapitalization (Details)		3 Months Ended	9 Months Ended
Reverse Recapitalization (Details)	Aug. 26, 2021 USD ($) $ / shares tranche shares	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Feb. 17, 2021 tranche shares
Business Acquisition [Line Items]
Legacy Humacyte common stock conversion ratio to common stock	0.26260
Founder shares converted to commons stock \| shares	2,500,000
Founder shares conversion ratio	1.00
Maximum contingent earnout shares \| shares	15,000,000			15,000,000
Number of tranches of contingent earnout shares \| tranche	2			2
Number of contingent earnout shares per tranche \| shares	7,500,000			7,500,000
Closing stock price to trigger first trance of contingent earnout shares (USD per share) \| $ / shares	$ 15.00
Closing stock price to trigger second trance of contingent earnout shares (USD per share) \| $ / shares	$ 20.00
Number of days within 30 day period of stock price at $15 or $20 to trigger earnout shares \| $ / shares	20
Period of over which 20 days stock price at $15 or $20 to trigger earnout shares	30 days
Contingent Consideration Liability recognized upon the closing of the reverse recapitalization	$ 159,400,000		$ 159,432,000
Proceeds from PIPE	$ 175,000,000
Share Price \| $ / shares	$ 10.00
Proceeds from merger	$ 242,400,000		242,400,000
Transaction costs recorded in APIC	3,900,000
Public warrants assumed upon the merger, net of transaction costs	100,000	$ 13,912,000
Liabilities assumed	15,200,000
Assets	$ 100,000
Accounts Payable and Accrued Liabilities [Member]
Business Acquisition [Line Items]
Unpaid assumed liabilities		2,200,000	2,200,000
Unpaid transaction costs		$ 3,000,000.0	$ 3,000,000.0

Reverse Recapitalization - Share After Merger (Details) - shares	Aug. 26, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019
Reverse Recapitalization
Common stock of AHAC, outstanding prior to Merger	10,355,000
Less redemption of AHAC shares	(3,008,551)
Common stock of AHAC	7,346,449
AHAC Founder Shares	2,500,000
New Humacyte shares issued to PIPE Investors	17,500,000
Issuance of common stock upon reverse recapitalization and PIPE Financing	27,346,449
New Humacyte shares issued in Merger to Legacy Humacyte stockholders	75,656,935
Total shares of common stock immediately after Merger	103,003,384	103,003,384	5,822,396	5,627,157
Common stock issued upon conversion of Legacy Humacyte's redeemable convertible preferred stock	69,613,562

Fair Value Measurements (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Financial assets	$ 238,375	$ 35,623
Liabilities:
Financial liabilities	169,755
Contingent earnout liability
Liabilities:
Financial liabilities	169,200
Private Placement Warrants
Liabilities:
Financial liabilities	555
Money market funds
Assets:
Financial assets	238,375	35,623
Level 1
Assets:
Financial assets	238,375	35,623
Level 1 \| Money market funds
Assets:
Financial assets	238,375	$ 35,623
Level 3
Liabilities:
Financial liabilities	169,755
Level 3 \| Contingent earnout liability
Liabilities:
Financial liabilities	169,200
Level 3 \| Private Placement Warrants
Liabilities:
Financial liabilities	$ 555

Fair Value Measurements - Changes in the fair value (Details)	9 Months Ended
	Sep. 30, 2021 USD ($) Y	Aug. 26, 2021 USD ($)
Contingent earnout liability \| Expected term
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input	10.00	10.00
Level 3 \| Contingent earnout liability
Changes in the fair value of the Level 3 financial instruments
Fair value of liability recognized	$ (159,432,000)
Change in fair value included in other (expense) income	(9,768,000)
Ending balance	(169,200,000)
Level 3 \| Private Placement Warrants
Changes in the fair value of the Level 3 financial instruments
Fair value of liability recognized	(553,000)
Change in fair value included in other (expense) income	(2,000)
Ending balance	$ (555,000)

Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 55,410		$ 55,410		$ 55,239	$ 55,705
Accumulated depreciation	(18,911)		(18,911)		(14,261)	(8,417)
Property and equipment, net	36,499		36,499		40,978	47,288
Depreciation expense	1,500	$ 1,600	4,650	$ 4,729	6,291	4,689
Scientific equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	27,578		27,578		27,412	27,822
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	154		154		149	218
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	335		335		335	340
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	988		988		988	988
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 26,355		$ 26,355		$ 26,355	$ 26,337

Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Accrued Expenses
Accrued external research, development and manufacturing costs	$ 2,685	$ 2,615	$ 3,872
Accrued employee compensation and benefits	4,025	1,009	1,260
Accrued professional fees	2,712	968	868
Total	$ 9,422	$ 4,592	$ 6,000	$ 7,049

Debt - PPP (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended		12 Months Ended
Debt - PPP (Details) - USD ($) $ in Thousands	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Proceeds from debt instruments			$ 3,251	$ 3,251
Gain on PPP loan forgiveness		$ 3,284
Paycheck Protection Program
Debt Instrument [Line Items]
Proceeds from debt instruments	$ 3,300
Gain on PPP loan forgiveness		$ 3,284

Debt - Term Loan (Details) $ / shares in Units, $ in Millions		1 Months Ended	9 Months Ended
	Oct. 13, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) shares	Sep. 30, 2021 USD ($) tranche $ / shares shares	Aug. 26, 2021 $ / shares	Mar. 15, 2006 $ / shares
Line of Credit Facility [Line Items]
Warrants, exercise price \| $ / shares				$ 11.50	$ 1.14
Silicon Valley Bank and SVB Innovation Credit Fund VIII, L.P.,
Line of Credit Facility [Line Items]
Percent of outstanding principal and interest collateralized			50.00%
Term loan agreement
Line of Credit Facility [Line Items]
Number of tanches \| tranche			3
Amount of loan drawn	$ 10.0	$ 20.0
Amount that are eligible to disburse			$ 10.0
Borrowings bearing interest rate			7.50%
Advance notice period			30 days
Prepayment fee			3.00%
Prepayment fee after March 30, 2022			2.00%
Prepayment fee after March 30, 2023			1.00%
Warrants, exercise price \| $ / shares			$ 10.28
Warrants immediately exercisable \| shares			287,704
Fair value of warrants			$ 2.4
Final payment fee (as a percent)			5.00%
Final payment fee			$ 1.0
Debt issuance costs			$ 0.3
Number of warrants with no probable funding that becomes exercisable \| shares		123,302
Number of warrants that becomes exercisable for no probable funding \| shares	123,302
Exercise price of warrants that became exercisable for no probable funding (USD per share) \| $ / shares	$ 10.28
Term loan agreement \| Prime Rate
Line of Credit Facility [Line Items]
Borrowings bearing interest rate			7.50%
Basis spread on variable rate			4.25%
Term loan agreement \| Silicon Valley Bank and SVB Innovation Credit Fund VIII, L.P.,
Line of Credit Facility [Line Items]
Maximum loan facility amount		$ 50.0

Debt - SVB loan payable and net discount (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
SVB loan payable, current and noncurrent	$ 20,000
SVB Loan payable
Debt Instrument [Line Items]
Principal amount of SVB loan payable	20,000
Final payment amount of SVB loan payable	1,000
Net premium associated with accretion of final payment and other debt issuance costs	(3,073)
SVB loan payable, current and noncurrent	17,927
Less SVB loan payable, current portion	(3,889)
SVB loan payable, noncurrent portion	$ 14,038

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Debt - Future minimum payments (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Future minimum payments of principal and estimated payments of interest
2022	$ 5,555
2023	6,667
2024	6,667
2025	1,111
Total future payments	20,000
SVB Loan payable
Future minimum payments of principal and estimated payments of interest
Total future payments	17,927
Less final payment	(1,000)
Total principal amount of SVB loan payments	$ 20,000