HSTO Histogen Inc

NOTES TO UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

1. Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies

Description of Business

Histogen Inc. (the “Company,” “Histogen,” “we,” or the “combined company”), formerly known as Conatus Pharmaceuticals Inc. (“Conatus”), was incorporated in the state of Delaware on July 13, 2005. The Company is a clinical-stage therapeutics company focused on developing potential first-in-class restorative therapeutics that ignite the body’s natural process to repair and maintain healthy biological function.

Merger between Private Histogen and Conatus Pharmaceuticals Inc. and Name Change

On January 28, 2020, the Company, then operating as Conatus, entered into an Agreement and Plan of Merger and Reorganization, as amended (the “Merger Agreement”), with privately-held Histogen, Inc. (“Private Histogen”) and Chinook Merger Sub, Inc., a wholly-owned subsidiary of the Company (“Merger Sub”). Under the Merger Agreement, Merger Sub merged with and into Private Histogen, with Private Histogen surviving as a wholly-owned subsidiary of the Company (the “Merger”). On May 26, 2020, the Merger was completed.  Conatus changed its name to Histogen Inc., and Private Histogen, which remains as a wholly-owned subsidiary of the Company, changed its name to Histogen Therapeutics Inc. On May 27, 2020, the combined company’s common stock began trading on The Nasdaq Capital Market under the ticker symbol “HSTO”.

Liquidity and Going Concern

The Company has incurred operating losses and negative cash flows from operations and had an accumulated deficit of $78.3 million as of March 31, 2022. The Company expects operating losses and negative cash flows from operations to continue for the foreseeable future. As of March 31, 2022, the Company had $17.8 million in cash and cash equivalents.

The Company has not yet established ongoing sources of revenues sufficient to cover its operating costs and will need to continue to raise additional capital to support its future operating activities, including progression of its development programs, preparation for commercialization, and other operating costs. Management’s plans with regard to these matters include entering into a combination of additional debt or equity financing arrangements, strategic partnerships, collaboration and licensing arrangements, or other similar arrangements. In addition, the Company may fund its losses from operations through the common stock purchase agreement the Company entered into with Lincoln Park in July 2020, for the purchase of up to $10.0 million of the Company’s common stock over the 24 month period of the purchase agreement, $8.5 million of which remains available for sale as of the date these condensed consolidated financial statements were available to be issued (refer to Note 7 for further information), subject to limitations on the amount of securities the Company may sell under its effective registration statement on Form S-3 within any 12-month period. There can be no assurance that the Company will be able to obtain additional financing on terms acceptable to the Company, on a timely basis or at all. Based on the Company’s current operating plan, management believes that existing cash and cash equivalents will be sufficient to fund the Company’s obligations for at least 12 months after these condensed consolidated financial statements are issued.

The condensed consolidated financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business.

Basis of Presentation and Principles of Consolidation

The condensed consolidated financial statements include the accounts of the Company and its controlled subsidiaries, including Histogen Therapeutics, Inc., and have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”). All intercompany balances and transactions have been eliminated upon consolidation.

The Company acquired Centro De Investigacion de Medicina Regenerativa, S.A. de C.V. (“CIMRESA”), a company in Mexico, during 2018 to facilitate a potential clinical development program for HST-001, or hair stimulating complex (“HSC”). This is a wholly-owned subsidiary intended to pursue registration with the COFEPRIS (Mexico equivalent to Food and Drug Administration). CIMRESA had no operational or financial activity for the three months ended March 31, 2022 and 2021.

The Company holds a majority interest in Adaptive Biologix, Inc. (“AB”, formerly Histogen Oncology, LLC). AB was formed to develop and market applications for the treatment of cancer. The Company consolidates AB into its condensed consolidated financial statements.

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Unaudited Interim Financial Information

The unaudited condensed consolidated financial statements for the three months ended March 31, 2022 and 2021 have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (“SEC”) and GAAP. Accordingly, these condensed consolidated financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of Management, these unaudited interim condensed consolidated financial statements contain all adjustments necessary, all of which are of a normal and recurring nature, to present fairly the Company’s financial position, results of operations, and cash flows. Interim results are not necessarily indicative of results for a full year or future periods. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes thereto for the year ended December 31, 2021 included in the Annual Report on Form 10-K that the Company filed with the SEC on March 10, 2022.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and the disclosure of contingent assets and liabilities and contingencies at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the periods presented. Management believes that these estimates and assumptions are reasonable, however, actual results may differ and could have a material effect on future results of operations and financial position. Though the impact of the COVID-19 pandemic on the Company’s business and operating results presents additional uncertainty, Company’s management continues to use the best information available to them in their significant accounting estimates.

Significant estimates and assumptions include the useful lives of property and equipment, discount rates used in recognizing contracts containing leases, unrecognized tax benefits, reserves for excess or obsolete inventory, stock-based compensation, and best estimate of standalone selling price of revenue deliverables. Actual results may materially differ from those estimates.

Variable Interest Entities

The Company determined that AB is a variable interest entity (“VIE”) and that the Company is its primary beneficiary. The Company holds greater than 50% of the shares and has the authority to manage the business and affairs of the VIE. AB’s other shareholder does not have a controlling interest.

A VIE is typically an entity for which the Company has less than a 100% equity interest but controls the decision making over the business and affairs of the entity, directs the decisions driving the economic performance of such entity and participates in the profit and losses of such an entity. The Company weighed both quantitative and qualitative information about the different risks and reward characteristics of each entity and the significance of that entity to the consolidating group in the aggregate.

Segment Reporting

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker, the Interim Chief Executive Officer, in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one operating segment.

Cash, Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments purchased with an original maturity date of ninety days or less to be cash equivalents. Cash and cash equivalents include cash in readily available checking, money market accounts and brokerage accounts.

The Company’s current restricted cash consists of cash held as collateral for a letter of credit issued as a security deposit for the lease of the Company’s headquarters and is required to be held throughout the lease term.

Risks and Uncertainties

Credit Risk

At certain times throughout the year, the Company may maintain deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash balances due to the financial position of the depository institutions in which those deposits are held.

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Customer Risk

During the three months ended March 31, 2022 and 2021, one customer accounted for 100% and 72% of total revenues.

COVID-19

The cumulative effect of the COVID-19 outbreak and associated disruptions have had, and may continue to have, an adverse impact on the Company’s business and its results of operations. The full impact of the COVID-19 outbreak continues to evolve as of the date these condensed consolidated financial statements were available to be issued and will depend on future developments that are highly uncertain and unpredictable, including efficacy and adoption of vaccines, future resurgences of the virus and its variants, and the speed at which government restrictions are lifted. As such, it is uncertain as to the full magnitude that the pandemic will have on the Company’s financial condition, liquidity, and future results of operations.

Accounts Receivable

Accounts receivable are generally due within 30 days and are recorded at net realizable value, which is determined using historical experience. The Company maintains an allowance for doubtful accounts for potential credit losses. The allowance is based on an analysis of historical bad debt, current receivables aging, and expected future write-offs of uncollectible accounts, as well as an assessment of specific identifiable accounts considered at risk or uncollectible. Additions to the allowance for doubtful accounts include provisions for bad debt and deductions from the allowance for doubtful accounts include customer write-offs. Provision for doubtful accounts was not material for all periods presented.

Property and Equipment

Property and equipment are reported net of accumulated depreciation and amortization and are comprised of office furniture and equipment, lab and manufacturing equipment, and leasehold improvements. Ordinary maintenance and repairs are charged to expense, while expenditures that extend the physical or economic life of the assets are capitalized. Furniture and all equipment are depreciated over their estimated useful lives, or five years, using the straight-line method. Software is amortized over its estimated useful lives, or three years, using the straight-line method. Leasehold improvements are amortized over their estimated useful lives and limited by the remaining term of the building lease, using the straight-line method.

Valuation of Long-Lived Assets

Long-lived assets to be held and used, including property and equipment, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be recoverable. As of March 31, 2022, the Company has not recognized any impairment to long-lived assets.

Forward Purchase Contract

In 2011, Private Histogen contracted for research services from EPS Global Research Pte. Ltd. (“EPS”) to conduct clinical trials and compile data from a study that took place in 2011 and 2013. The unpaid amount due for the services was approximately $0.3 million.

In 2017, Private Histogen and EPS entered into a Debt Settlement and Conversion Agreement (“Settlement Agreement”) whereby Private Histogen paid $50 thousand and issued EPS 14,342 shares of Series D convertible preferred stock. The Company was required to repurchase the shares at the greater of the remaining balance due of approximately $0.3 million and the market price of the shares at the time of repurchase, but in no event later than December 31, 2021. The Company had the sole option to repurchase the shares (which were converted from Series D convertible preferred stock into shares of common stock upon the Merger) at any time on or before December 31, 2021.

On December 16, 2021, the Company repurchased from EPS 14,342 shares of common stock in exchange for a cash payment of approximately $0.3 million. The repurchased shares were recorded as treasury stock and retired as of March 31, 2022. As of December 31, 2021, no further amounts are due to EPS under the Settlement Agreement.

Comprehensive Income (Loss)

The Company is required to report all components of comprehensive income (loss), including net income (loss), in the accompanying condensed consolidated financial statements in the period in which they are recognized. Comprehensive income (loss) is defined as

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the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on investments and foreign currency translation adjustments. Net loss and comprehensive loss were the same for all periods presented.

Revenue Recognition

Product and License Revenue

The Company records revenue in accordance with ASC 606, Revenue from Contracts with Customers, whereby revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration expected to be received in exchange for those goods or services. A five-step model is used to achieve the core principle: (1) identify the customer contract, (2) identify the contract’s performance obligations, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations and (5) recognize revenue when (or as) a performance obligation is satisfied. The Company applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. Shipping charges billed to customers are included in product revenue and the related shipping costs are included in cost of product revenue. The Company applies the revenue recognition standard, including the use of any practical expedients, consistently to contracts with similar characteristics and in similar circumstances (See Note 4).

Grant Awards

In March 2017, the National Science Foundation (“NSF”), a government agency, awarded the Company a research and development grant to develop a novel wound dressing for infection control and tissue regeneration. The Company has concluded this government grant is not within the scope of ASC 606, as government entities generally do not meet the definition of a “customer” as defined by ASC 606. Payments received under the grant are considered conditional, non-exchange contributions under the scope of ASC 958-605, Not-for-Profit Entities – Revenue Recognition, and are recorded as revenue in the period in which such conditions are satisfied. In reaching the determination that such payments should be recorded as revenue, management considered a number of factors, including whether the Company is a principal under the arrangement, and whether the arrangement is significant to, and part of, the Company’s ongoing operations. As of March 31, 2021, the Company had completed all obligations under the NSF development grant and, as such, no longer generates any revenues in connection with the research and development grant.

In September 2020, the Company was approved for a grant award from the U.S. Department of Defense (“DoD”) in the amount of approximately $2.0 million to partially fund the Company’s planned Phase 1/2 clinical trial of HST-003 for regeneration of cartilage in the knee. The Company applies International Accounting Standard (“IAS”) 20, Accounting for Government Grants and Disclosure of Government Assistance, by analogy as there is no existing authoritative guidance under GAAP. Under the terms of the award, the DoD will reimburse the Company for certain allowable costs. The period of performance for the grant award substantially expires in September 2025 and is subject to annual and quarterly reporting requirements. As the DoD grant is a cost-type (reimbursement) grant, the Company must incur program expenses in accordance with the Statement of Work and approved budget in order to be reimbursed by the DoD. The Company will recognize funding received from the grant award as a reduction of research and development expenses in the period in which qualifying expenses have been incurred, as the Company is reasonably assured that the expenses will be reimbursed and the funding is collectible. For the three months ended March 31, 2022 and 2021, qualifying expenses totaling $0.2 million for each reporting period have been incurred with a corresponding reduction of research and development expenses related to the award. As of March 31, 2022 and December 31, 2021, $67 thousand and $0.2 million, respectively, was included in accounts receivable within the condensed consolidated balance sheets with respect to the award.

Cost of Product Revenue

Cost of product revenue represents direct and indirect costs incurred to bring the product to saleable condition.

Research and Development Expenses

All research and development costs are charged to expense as incurred. Research and development expenses primarily include (i) payroll and related costs associated with research and development performed, (ii) costs related to clinical and preclinical testing of the Company’s technologies under development, and (iii) other research and development costs including allocations of facility costs, net of reimbursable research and development costs incurred under the DoD grant.

General and Administrative Expenses

General and administrative expenses represent personnel costs for employees involved in general corporate functions, including finance, accounting, legal and human resources, among others. Additional costs included within general and administrative expenses

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consist of professional fees for legal (including patent costs), audit and other consulting services, travel and entertainment, recruiting, allocated facility and general information technology costs, depreciation and amortization, and other general corporate overhead expenses.

Patent Costs

The Company expenses all costs as incurred in connection with patent applications (including direct application fees, and the legal and consulting expenses related to making such applications) and such costs are included in general and administrative expenses in the accompanying condensed consolidated statements of operations.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred income taxes are recorded for temporary differences between condensed consolidated financial statement carrying amounts and the tax basis of assets and liabilities. Deferred tax assets and liabilities reflect the tax rates expected to be in effect for the years in which the differences are expected to reverse. No income tax expense or benefit was recorded for the three months ended March 31, 2022 and 2021, due to the full valuation allowance on the Company’s net deferred tax assets. A valuation allowance is provided if it is more likely than not that some or all the deferred tax assets will not be realized.

The Company also follows the provisions of accounting for uncertainty in income taxes which prescribes a model for the recognition and measurement of a tax position taken or expected to be taken in a tax return, and provides guidance on derecognition, classification, interest and penalties, disclosure, and transition.

The Company’s policy is to recognize interest or penalties related to income tax matters in income tax expense. Interest and penalties related to income tax matters were not material for the periods presented.

Net Loss Per Share

Basic net loss per share attributable to common stockholders is computed by dividing net loss attributable to common stockholders by the weighted-average common shares outstanding during the period, without consideration for potentially dilutive securities. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares and potentially dilutive securities outstanding for the period.

Potentially dilutive common shares consist of shares issuable from warrants, stock options, and redeemable convertible preferred stock. Potentially dilutive common shares issuable upon vesting of stock options and warrants are determined using the average share price for each period under the treasury stock method. In periods of net losses, the Company excludes all potentially dilutive common shares from the computation of diluted net loss per share for the periods as the effect would be anti-dilutive.

For the three months ended March 31, 2022 and 2021, diluted net loss per share attributable to common stockholders is equal to the basic net loss per share attributable to common stockholders as common stock equivalent shares from stock options and warrants were anti-dilutive.

The following table sets forth outstanding potentially dilutive shares that have been excluded from the calculation of diluted net loss per share attributable to common stockholders because of their anti-dilutive effect (in common stock equivalents):

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Stock-Based Compensation

Service-Based Awards

The Company recognizes stock-based compensation expense for service-based stock options and restricted stock units (“RSUs”) over the requisite service period on a straight-line basis. Employee and director stock-based compensation for service-based stock options is measured based on estimated fair value as of the grant date using the Black-Scholes option pricing model. The Company estimates the fair value of RSUs based on the closing price of the Company’s common stock on the date of issuance. The Company uses the following assumptions for estimating fair value of service-based option grants:

Fair Value of Common Stock – The fair value of common stock underlying the option grant is determined based on observable market prices of the Company’s common stock.

Expected Volatility – Volatility is a measure of the amount by which the Company’s share price has historically fluctuated or is expected to fluctuate (i.e., expected volatility) during a period. Due to the lack of an adequate history of a public market for the trading of the Company’s common stock and a lack of adequate company-specific historical and implied volatility data, volatility has been estimated and based on the historical volatility of a group of similar companies that are publicly traded. For these analyses, the Company has selected companies with comparable characteristics, including enterprise value, risk profiles, and position within the industry, and with historical share price information sufficient to meet the expected term of the stock-based awards.

Expected Term – This is the period of time during which the options are expected to remain unexercised. Options have a maximum contractual term of ten years. The Company estimates the expected term of stock options using the “simplified method”, whereby the expected term equals the average of the vesting term and the original contractual term of the underlying option.

Risk-Free Interest Rate – This is the observed yield on zero-coupon U.S. Treasury securities, as of the day each option is granted, with a term that most closely resembles the expected term of the option.

Expected Forfeiture Rate – Forfeitures are recognized as they occur.

Performance-Based Options

Stock-based compensation expense for performance-based options is recognized based on amortizing the fair market value as of the grant date over the periods during which the achievement of the performance is probable. Performance-based options require certain performance conditions to be achieved in order for these options to vest. These options vest on the date of achievement of the performance condition.

Market-Based Options

Stock-based compensation expense for market-based options is recognized on a straight-line basis over the derived service period, regardless of whether the market condition is satisfied. Market-based options subject to market-based performance targets require achievement of the performance target in order for these options to vest. The Company estimates the fair value of market-based options as of the grant date and expected term using a Monte Carlo simulation that incorporates option-pricing inputs covering the period from the grant date through the end of the derived service period.

Recently Issued Accounting Pronouncements Not Yet Adopted

None

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) (“ASU 2020-06”). This new guidance is intended to simplify the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible instruments and contracts on an entity’s own equity. Entities may adopt ASU 2020-06 using either a partial retrospective or fully retrospective method of transition. This ASU is effective for public business entities for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years, with early adoption permitted. The Company adopted ASU 2020-06 on January 1, 2022. The adoption of this standard did not have a material impact on the Company’s condensed consolidated financial statements or related disclosures.

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In November 2021, the FASB issued ASU No. 2021-10, Government Assistance (Topic 832): Disclosure by Business Entities about Government Assistance (“ASU 2021-10”), which improves the transparency of government assistance received by certain business entities by requiring the disclosure of (1) the types of government assistance received; (2) the accounting for such assistance, and (3) the effect of the assistance on the business entity’s financial statements. ASU 2021-10 is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted ASU 2021-10 on January 1, 2022. The adoption of this standard did not have a material impact on the Company’s condensed consolidated financial statements or related disclosures

2. Property and Equipment, Net

Property and equipment, net consisted of the following (in thousands):

Depreciation and amortization expense for the three months ended March 31, 2022 and 2021, were $31 thousand and $23 thousand, respectively.

3. Balance Sheet Details

Prepaid and other current assets consisted of the following (in thousands):

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Other assets consisted of the following (in thousands):

Accrued liabilities consisted of the following (in thousands):

4. Revenues

The following is a summary description of the material revenue arrangements, including arrangements that generated revenues during the three months ended March 31, 2022 and 2021.

Allergan License Agreements

2017 Allergan Amendment

In 2017, the Company entered into a series of agreements (collectively, the “2017 Allergan Agreement”), which ultimately transferred Suneva Medical, Inc.’s license and supply rights of Histogen’s cell conditioned medium (“CCM”) skin care ingredient in the medical aesthetics market to Allergan Sales LLC (“Allergan”) and granted Allergan an exclusive, royalty-free, perpetual, irrevocable, non-terminable and transferable license, including the right to sublicense to third parties, to use the Company’s CCM skin care ingredient in the medical aesthetics market. The 2017 Allergan Agreement also obligated the Company to deliver CCM to Allergan (the “Supply of CCM to Allergan”) in the future as well as share with Allergan any potential future improvements to the Company’s CCM skin care ingredients identified through the Company’s research and development efforts (“Potential Future Improvements”).  In consideration for the execution of the agreements, Histogen received a cash payment of $11.0 million and a potential additional payment of $5.5 million if Allergan’s net sales of products containing the Company’s CCM skin care ingredient exceeds $60.0 million in any calendar year through December 31, 2027.

2019 Allergan Amendment

In March 2019, Histogen entered into a separate agreement with Allergan (the “2019 Allergan Amendment”) to amend the 2017 Allergan Agreement in exchange for a one-time payment of $7.5 million to the Company. The agreement broadened Allergan’s license rights, expanding Allergan’s access to certain sales channels where its products incorporating the CCM ingredient can be sold. Specifically, the license was broadened to provide Allergan the exclusive right to sell through the “Amazon Professional” website, or any website or digital platform owned or licensed by Allergan or under the Allergan brand name, and non-exclusive rights to sell on other websites and through brick-and-mortar medical spas and wellness centers (excluding websites and brick-and-mortar stores of luxury brands).

The Company evaluated the 2019 Allergan Amendment under ASC 606 and concluded that Allergan continues to be a customer and that the expanded license is distinct from the 2017 Allergan Agreement. The Company determined the expanded license under the 2019 Allergan Amendment to be functional intellectual property as Allergan has the right to utilize the Company’s CCM skin care ingredient, and that ingredient is functional to Allergan at the time the Company transferred the expanded license.

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The standalone selling price of the expanded license was not readily observable since the Company has not yet established a price for this expanded license and the expanded license has not been sold on a standalone basis to any customer. The Company accounted for the 2019 Allergan Amendment as a modification to the 2017 Allergan Agreement. The contract modification was accounted for as if the 2017 Allergan Agreement had been terminated and the new contract included the expanded license as well as the remaining performance obligations that arose from the 2017 Allergan Agreement related to the Supply of CCM to Allergan and Potential Future Improvements.

The total transaction price for the new contract included the $7.5 million from the 2019 Allergan Amendment as well as the amounts deferred as of the 2019 Allergan Amendment execution date for each the Supply of CCM to Allergan and Potential Future Improvements.

The standalone selling price for the Supply of CCM to Allergan was determined based on comparable sales transactions. The standalone selling price of the Potential Future Improvements was estimated at the fully burdened rate of research and development employees cost plus a commercially reasonable markup. The amount of the total transaction price allocated to the expanded license was determined using the residual approach as a result of not having a standalone selling price for the expanded license; that is, the total transaction price less the standalone selling prices of the Supply of CCM to Allergan and Potential Future Improvements.

Revenue related to the Supply of CCM to Allergan has been deferred and recognized at the point in time in which deliveries are completed while revenue related to the Potential Future Improvements has been deferred and amortized ratably over the remaining 9-year life of the patent. The Supply of CCM to Allergan under the 2019 Allergan Amendment was entirely fulfilled during the year ended December 31, 2019. The $7.5 million residual amount of the total transaction price allocated to the expanded license was recognized as license revenue upon transfer of the license to Allergan in March 2019.

2020 Allergan Amendment

In January 2020, the Company further amended the 2019 Allergan Amendment in exchange for a one-time payment of $1.0 million to the Company (the “2020 Allergan Amendment”). The 2020 Allergan Amendment further broadened Allergan’s exclusive and non-exclusive license rights to include products used for or in connection with microdermabrasion. In addition, the Company agreed to provide Allergan with an additional 200 kilograms of CCM (the “Additional Supply of CCM to Allergan”).

The Company evaluated the 2020 Allergan Amendment under ASC 606 and concluded that Allergan continues to be a customer and that the expanded license is distinct from the 2019 Allergan Amendment. The Company determined the expanded license under the 2020 Allergan Amendment to be functional intellectual property as Allergan has the right to utilize the Company’s CCM skin care ingredient, and that ingredient is functional to Allergan at the time the Company transferred the expanded license.

The standalone selling price of the expanded license was not readily observable since the Company has not yet established a price for this expanded license and the expanded license has not been sold on a standalone basis to any customer. The Company accounted for the 2020 Allergan Amendment as a modification to the 2019 Allergan Amendment (which had modified the 2017 Allergan Agreement, as noted above). The contract modification was accounted for as if the 2019 Allergan Amendment had been terminated and the new contract included the expanded license and Additional Supply of CCM to Allergan, as well as the remaining performance obligation related to Potential Future Improvements.

The total transaction price for the new contract included the $1.0 million from the 2020 Allergan Amendment, the future payment for the Additional Supply of CCM to Allergan, as well as the amounts deferred as of the 2020 Allergan Amendment execution date for Potential Future Improvements.

The standalone selling price for the Additional Supply of CCM to Allergan was determined using the observable inputs of historical comparable sales transactions, including the margin from such sales. The Company also considered its reduced expected cost of satisfying this performance obligation based on the current efficiencies within its CCM manufacturing processes. Due to significant efficiencies in the Company’s CCM manufacturing processes, the forecasted cost of CCM production has decreased, while the applied margin was determined by comparison to similar sales transactions in prior years. The standalone selling price of the Potential Future Improvements was estimated at the fully burdened rate of research and development employees cost plus a commercially reasonable markup. The amount of the total transaction price allocated to the expanded license was determined using the residual approach, as a result of not having a standalone selling price for the expanded license; that is, the total transaction price less the standalone selling prices of the Additional Supply of CCM to Allergan and Potential Future Improvements.

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Under the Amended and Restated License Agreement, as amended, Allergan will indemnify the Company for third party claims arising from Allergan’s breach of the agreement, negligence or willful misconduct, or the exploitation of products by Allergan or its sublicensees. The Company will indemnify Allergan for third party claims arising from the Company’s breach of the agreement, negligence or willful misconduct, or the exploitation of products by the Company prior to the effective date. Allergan may terminate the Agreement for convenience upon one business days’ notice to the Company.

Revenue related to the Additional Supply of CCM to Allergan was deferred and was recognized at the point in time in which deliveries were completed. Revenue for the three months ended March 31, 2021 was $0.3 million ($28 thousand of which was previously deferred). All deliveries of Additional Supply of CCM to Allergan have been completed as of March 31, 2021. Revenue related to the Potential Future Improvements has been deferred and amortized ratably over the remaining 9-year life of the patent, for which $5 thousand of previously deferred revenue was recognized in revenue during each of the three months ended March 31, 2022 and 2021, respectively. The $0.9 million residual amount of the total transaction price allocated to the expanded license was recognized as license revenue upon transfer of the license to Allergan in January 2020.

In August 2021, unrelated to the Allergan Agreements, the Company agreed to a sale of CCM under a purchase order with Allergan.  The CCM sold to Allergan was initially manufactured by the Company for research and development purposes in support of its product candidates. In September 2021, the Company recognized $0.6 million of product revenue related to the sale. The Company does not have any additional purchase orders with Allergan for fulfillment.

2022 Allergan Letter Agreement

Pursuant to the 2017 Allergan Amendment, Histogen had the right to a potential milestone payment of $5.5 million if Allergan’s net sales of products containing the Company’s CCM skin care ingredient exceeds $60.0 million in any calendar year through December 31, 2027. In lieu of the potential milestone payment of $5.5 million, the Company entered into a letter agreement on March 18, 2022 (the “Letter Agreement”) with Allegan. In consideration for the execution of the Letter Agreement, Histogen received a one-time payment equal to $3.8 million (the “Final Payment”) in March 2022. In exchange, among other things, the Company agreed that the Final Payment represents a full and final satisfaction of all money due to the Company pursuant to the License Agreement. The Company evaluated the 2022 Allergan Letter Agreement under ASC 606 and concluded that the performance obligation has been satisfied and therefore used point in time recognition. The Company recognized $3.8 million of license revenue related to the Letter Agreement during the three months ended March 31, 2022. The Letter Agreement did not have an impact on the remaining performance obligation to share with Allergan any Potential Future Improvements to CCM identified through the Company’s research and development efforts.

Remaining Performance Obligation and Deferred Revenue

The remaining performance obligation is the Company’s obligation to share with Allergan any Potential Future Improvements to CCM identified through the Company’s research and development efforts. Deferred revenue recorded for the Potential Future Improvements was $0.1 million as of March 31, 2022 and December 31, 2021. Deferred revenue is classified in current portion of deferred revenue liabilities when the Company’s obligations to supply CCM or provide research for Potential Future Improvements are expected to be satisfied within twelve months of the balance sheet date.

Grant Revenue

In March 2017, the National Science Foundation (NSF), a government agency, awarded the Company a research and development grant to develop a novel wound dressing for infection control and tissue regeneration. Grant revenue recognized was $0 and $0.1 million for the three months ended March 31, 2022 and 2021. As of March 31, 2021, the Company has completed all obligations under the NSF development grant and, as such, no longer generates any revenues in connection with the research and development grant.

Amerimmune Collaborative Development and Commercialization Agreement

In October 2020, the Company entered into a Collaborative Development and Commercialization Agreement (the “Amerimmune Agreement”) with Amerimmune to jointly develop emricasan for the potential treatment of COVID-19. The FDA approved an investigational new drug application (IND) to initiate a Phase 1 study of emricasan in mild COVID-19 patients to assess safety and tolerability in 2020. Under the Amerimmune Agreement, Amerimmune, at its expense and in collaboration with the Company, shall use commercially reasonable efforts to lead the development activities for emricasan. Amerimmune is responsible for conducting clinical trials and the Company agreed to provide reasonable quantities of emricasan for such purpose. Each party shall retain ownership of their legacy intellectual property and responsibility for ongoing patent application prosecution and maintenance costs. In

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addition, the Company granted Amerimmune an exclusive option, subject to certain terms and conditions, to an exclusive license to develop and commercialize emricasan throughout the world during the term of the Amerimmune Agreement.  After exercise of the option, Amerimmune, alone or in conjunction with one or more strategic partners, will use its commercially reasonable efforts to develop, manufacture, and commercialize emricasan and the Company will share the profits equally with Amerimmune.  No consideration will be transferred to the Company until profits, as defined in the Amerimmune Agreement, are generated by Amerimmune from developing or commercializing products.

Pursuant to the terms of the Collaborative Agreement, each party shall retain ownership of their legacy intellectual property and responsibility for ongoing patent application prosecution and maintenance costs and will jointly own any intellectual property developed during the term of the agreement. In addition, the Company granted Amerimmune an exclusive option, subject to terms and conditions including completion of a Phase 2 clinical trial by Amerimmune during the research term, to obtain an exclusive license that, if granted by us, allows Amerimmune alone, or in conjunction with one or more strategic partners, to use its commercially reasonable efforts to develop, manufacture, and commercialize emricasan and other caspase modulators, including CTS-2090 and CTS-2096, and the Company will share the profits equally with Amerimmune. No consideration will be transferred to the Company until profits, as defined in the Amerimmune Agreement, are generated by Amerimmune from developing or commercializing products.

The Company has identified multiple promises to deliver goods and services, which include at the inception of the agreement: (i) a license to technology and patents, information, and know-how; (ii) supply of emricasan, and (iii) collaboration, including the Company’s participation in a Joint Development Committee and Joint Partnering Committee. At inception and through March 31, 2022, the Company has identified one performance obligation for all the deliverables under the Amerimmune Agreement since the delivered elements are either not capable of being distinct or are not distinct within the context of the contract. No upfront consideration was exchanged between the parties and any consideration received will be dependent on the successful execution of a qualifying strategic partnership, as defined, on the successful commercialization of emricasan, or upon a change in control of Amerimmune, as defined.  Although the Company will recognize revenue upon the occurrence of one of these events, no such events have occurred as of March 31, 2022.

On January 19, 2022, the Company provided a notice of material breach in connection with Amerimmune’s non-performance under the Collaborative Agreement and, on March 3, 2022, filed a demand for arbitration (“Arbitration Demand”). On March 11, 2022, Judicial Arbitration and Mediation Services, Inc. (“JAMS”) issued a Notice of Commencement of Arbitration letter, confirming the commencement of the arbitration as of that date. On March 8, 2022, Amerimmune provided written notice to exercise an option for additional license rights to develop additional products however, the Company has rejected Amerimmune’s election of the option and believes that Amerimmune no longer has such right to exercise the option based on, amongst other reasons, Histogen’s belief that the Agreement has been terminated as set forth in Histogen’s Arbitration Demand (refer to Note 8 for further information).

5. Paycheck Protection Program Loan

In April 2020, Private Histogen applied for and received loan proceeds in the amount of $0.5 million (the “PPP Loan”) under the PPP as government aid for payroll, rent, and utilities. The application for these funds required the Company to, in good faith, certify that the current economic uncertainty made the loan request necessary to support the ongoing operations of the Company. This certification further required the Company to take into account its current business activity and its ability to access other sources of liquidity sufficient to support ongoing operations in a manner that is not significantly detrimental to the business. The certification made by the Company did not contain any objective criteria and is subject to interpretation. Based in part on the Company’s assessment of other sources of liquidity, the uncertainty associated with future revenues created by the COVID-19 pandemic and related governmental responses, and the going concern uncertainty reflected in the Company’s condensed consolidated financial statements as of December 31, 2019, the Company believed in good faith that it met the eligibility requirements for the PPP Loan. If, despite the good-faith belief that given the Company’s circumstances all eligibility requirements for the PPP Loan were satisfied, it is later determined that the Company had violated any applicable laws or regulations or it is otherwise determined that the Company was ineligible to receive the PPP Loan, it may be required to repay the PPP Loan in its entirety and/or be subject to additional penalties and potential liabilities.

On June 5, 2020, the Paycheck Protection Program Flexibility Act was signed into law, extending the PPP Loan forgiveness period from eight weeks to twenty-four weeks after loan origination, extending the initial deferral period of principal and interest payments from six months to ten months after the loan forgiveness period, reducing the required amount of payroll expenditures from 75% to 60%, removing the prior ban on borrowers taking advantage of payroll tax deferral after loan forgiveness, and allowing for the amendment of the maturity date on existing loans from two years to five years.

On March 8, 2021 the Company applied for PPP loan forgiveness with its lender and subsequently received approval from the lender on April 2, 2021. The Company, in good faith, believes it maintained compliance with the PPP program requirements. On May 21, 2021, the Small Business Administration granted its forgiveness of 100% of the loan, or $0.5 million, which was recorded by the Company in the second quarter of 2021. The gain on forgiveness is reported as a component of other income in the condensed consolidated statement of operations.

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6. Redeemable Convertible Preferred Stock

The redeemable convertible preferred stock instruments are contingently redeemable preferred stock. Each series contains redemption features, voting rights, dividends, and conversion terms. The convertible preferred stock is presented on the condensed consolidated balance sheets as mezzanine equity.

March 2022 Offering

In March 2022, the Company completed a private placement offering (the “March 2022 Offering”) of (i) 2,500 shares of the Company’s Series A Redeemable Convertible Preferred Stock, par value $0.0001 per share (the “Series A Preferred Stock”), and (ii) 2,500 shares of the Company’s Series B Redeemable Convertible Preferred Stock, par value $0.0001 per share (the “Series B Preferred Stock” and together with the Series A Preferred Stock, the “Preferred Stock”), in each case, at an offering price of $952.38 per share, representing a 5% original issue discount to the stated value of $1,000 per share of Preferred Stock, for gross proceeds from the Offerings of approximately $4.76 million, before the deduction of the placement agent’s fee and other offering expenses. The shares of Series A Preferred Stock have a stated value of $1,000 per share and are convertible, at a conversion price of $1.00 per share, into 2,500,000 shares of common stock. The shares of Series B Preferred Stock have a stated value of $1,000 per share and are convertible, at a conversion price of $1.00 per share, into 2,500,000 shares of common stock. The closing occurred on March 25, 2022. The proceeds of $4.76 million are held in escrow and will only be disbursed to the Company upon conversion of the Series A and Series B Preferred Stock. Since the redeemable convertible preferred stock may be redeemed at the option of the holder, but is not mandatorily redeemable, the redeemable preferred stock has been classified as mezzanine equity and initially recognized at fair value of $4.76 million as mezzanine equity on the accompanying balance sheets.

In connection with the March 2022 Offering, the Company entered in a Registration Rights Agreement and agreed to file by July 20, 2022 a resale registration statement (the “Resale Registration Statement”) with the SEC covering all shares of Common Stock issuable upon conversion of the Preferred Stock that remains outstanding and has not previously been redeemed by the Company, and to cause the Resale Registration Statement to become effective by September 18, 2022 or, in the event of a full review of the Resale Registration Statement by the SEC, by October 18, 2022.

The March 2022 Offering generated gross proceeds of $4.76 million and the Company incurred cash-based placement agent fees and other offering expenses of approximately $0.5 million. The proceeds are held in escrow and disbursed to the Company only upon conversion of the Series A and Series B Preferred Stock.  The proceeds are included within current assets on the accompanying consolidated balance sheets.

In addition, the Company’s placement agent was issued compensatory warrants to purchase up to 7.0% of the aggregate number of shares of Preferred Stock sold in the offering (on an as-converted to common stock basis), resulting in common stock warrants to purchase up to 350,000 shares of common stock, with an exercise price of 125% of the offering price, or $1.25 per share, which are exercisable 6 months after issuance on or after September 25, 2022, and expire five and a half (5.5) years following the date of issuance on September 25, 2027.

The placement agent warrants, which are recorded as a component of mezzanine equity, were valued at an aggregate of $34 thousand dollars using the Black Scholes option pricing model based upon the following assumptions: expected volatility of 78.90%, risk-free interest rate of 2.40%, expected dividend yield of 0%, and an expected term of 5.5 years.

As of March 31, 2022, the Company had 350,000 shares of common stock reserved for issuance pursuant to the placement agent’s warrants issued by the Company in the March 2022 Offering at an exercise price of $1.25 per share.

Voting Rights

The shares of Preferred Stock have no voting rights, except that they only have the right to vote, with the holders of common stock, as a single class on a proposal to approve an amendment to our certificate of incorporation to effect a reverse stock split of our issued and outstanding common stock within a range, to be determined by our board of directors and set forth in such proposal. The Company plans to seek stockholder approval for the Reverse Stock Split Proposal at its annual meeting of stockholders.

Each share of Series A Preferred Stock outstanding on April 14, 2022 (“the Record Date”) has a number of votes equal to the number of shares of Common Stock issuable upon conversion of such share (whether or not such shares are then convertible). Accordingly, as of the Record Date, each share of Series A Preferred Stock has 3,776 votes, which is determined by dividing $1,000, the stated value of one share of Series A Preferred Stock, by $0.2648, the NASDAQ Minimum Price as of the closing on March 25, 2022. The holders

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of the Series A Preferred Stock have agreed to not transfer their shares of Series A Preferred Stock until after the Annual Meeting and to vote all shares of Series A Preferred Stock in favor of the Reverse Stock Split Proposal.

Each share of Series B Preferred Stock outstanding on the Record Date entitles the holder thereof to cast 30,000 votes on the Reverse Stock Split Proposal. The holders of the Series B Preferred Stock have agreed to not transfer their shares of Series B Preferred Stock until after the Annual Meeting and to vote all shares of Series B Preferred Stock in the same proportion as the aggregate shares of Common Stock and Series A Preferred Stock are voted on the Reverse Stock Split Proposal. As an example, if 70% of the aggregate votes cast by Common Stock and Series A Preferred Stock voting on the Reverse Stock Split Proposal are voted in favor thereof and 30% of the aggregate votes cast by Common Stock and Series A Preferred Stock voting on the Reverse Stock Split Proposal are voted against such Proposal, then 70% of the votes entitled to be cast by Series B Preferred Stock will be cast in favor of the proposal and 30% of such votes will be cast against the proposal.

Dividends

The holders of the redeemable convertible preferred stock are entitled to receive dividends on shares of Preferred Stock equal (on an as-if-converted-to-Common-Stock basis, disregarding for such purpose any conversion limitations hereunder) to and in the same form as dividends actually paid on shares of the Common Stock when, as and if such dividends are paid on shares of the Common Stock. No other dividends shall be paid on shares of Preferred Stock.

Conversion Rights

Each share of Preferred Stock is convertible, at any time and from time to time from and after the Reverse Stock Split Date at the option of the Holder thereof, into that number of shares of Common Stock determined by dividing the stated value per share of preferred stock by the conversion price. The shares of Series A Preferred Stock has a stated value of $1,000 per share and are convertible, at a conversion price of $1.00 per share, into 2,500,000 shares of common stock. The shares of Series B Preferred Stock have a stated value of $1,000 per share and are convertible, at a conversion price of $1.00 per share, into 2,500,000 shares of common stock.

Redemption Rights

Each share of Preferred Stock is redeemable after (i) the earlier of (1) the receipt of authorized stockholder approval for the reverse stock split and (2) the date that is 90 days following the Original Issue Date of March 25, 2022, and (ii) before the date that is 120 days after the Original Issue Date or July 23, 2022 (the “Redemption Period”), each stockholder shall have the right to cause the Company to redeem all or part of such stockholder’s shares of Preferred Stock at a price per share equal to 105% of the stated value of $1,000 per share.

7. Stockholders’ Equity

Common Stock

January 2021 Offering of Common Stock

In January 2021, the Company completed an S-1 offering (the “January 2021 Offering”) of an aggregate of 11,600,000 shares of common stock, pre-funded warrants to purchase up to 2,400,000 shares of its common stock, and common stock warrants to purchase up to an aggregate of 14,000,000 shares of common stock. To the extent that an investor determines, at their sole discretion, that they would beneficially own in excess of the Beneficial Ownership Limitations (or as such investor may otherwise choose), in lieu of purchasing shares of Common Stock and Common Warrants, such investor could have elected to purchase Pre-Funded Warrants and Common Warrants at the Pre-Funded Purchase Price in lieu of the shares of Common Stock and Common Warrants in such a manner to result in the same aggregate purchase price being paid by such investor to the Company. The combined purchase price of one share of common stock and the accompanying common stock warrant was $1.00, and the combined purchase price of one pre-funded warrant and accompanying common stock warrant was $0.9999. The common stock warrants are exercisable for five (5) years at an exercise price of $1.00 per share. The pre-funded warrants are immediately exercisable at an exercise price of $0.0001 per share and may be exercised at any time until all of the pre-funded warrants are exercised in full. Placement agent warrants were issued to purchase up to 700,000 shares of common stock, are immediately exercisable for an exercise price of $1.25, and are exercisable for five (5) years following the date of issuance. The Company received gross proceeds of $14.0 million and incurred placement agent’s fees and other offering expenses of approximately $1.9 million.

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The warrants and placement agent warrants were valued at $7.2 million and $0.3 million, respectively, using the Black-Scholes option pricing model based on the following assumptions: expected volatility 80.08%, risk-free interest rate 0.38%, expected dividend yield 0%, and an expected term of 5.0 years.

As of March 31, 2022 a total of 6,721,200 warrants issued in the January 2021 Offering to purchase shares of common stock have been exercised and the Company issued 6,721,200 shares of its common stock. The Company received gross proceeds of approximately $6.8 million.

As of March 31, 2022, the Company had 7,751,300 shares and 227,500 shares of common stock reserved for issuance pursuant to the warrants and placement agent’s warrants, respectively, issued by the Company in the January 2021 Offering, at an exercise price of $1.00 per share and $1.25 per share, respectively.

June 2021 Offering of Common Stock

In June 2021, the Company completed a registered direct offering (the “June 2021 Offering”) of an aggregate of 5,977,300 shares of common stock, together with accompanying warrants to purchase up to an aggregate of 4,781,840 shares of common stock, at a public offering price of $1.10 per share. The accompanying warrants permit the investor to purchase additional shares equal to 80% of the number of shares of the Company’s common stock purchased by the investor. The warrants have an exercise price of $1.00 per share, are immediately exercisable, and expire five and a half (5.5) years following the date of issuance. In addition, the Company’s placement agent was issued compensatory warrants equal to 5.0%, or 298,865 shares, of the aggregate number of common stock sold in the offering, which are immediately exercisable for an exercise price of $1.375 and expire five (5) years following the date of issuance on June 7, 2026. The Company received gross proceeds of $6.6 million and incurred cash-based placement agent fees and other offering expenses of approximately $0.9 million.

The warrants and placement agent warrants were valued at $3.0 million and $0.2 million, respectively, using a Black-Scholes option pricing model with the following assumptions: expected volatility 81.44% and 80.15%, risk-free interest rate 0.88% and 0.77%, expected dividend yield 0% and 0%, and an expected term of 5.5 years or 5.0 years, respectively.

As of March 31, 2022, no warrants associated with the June 2021 Offering have been exercised.

As of March 31, 2022, the Company had 4,781,840 shares and 298,865 shares of common stock reserved for issuance pursuant to the warrants and placement agent’s warrants, respectively, issued by the Company in the June 2021 Offering, at an exercise price of $1.00 per share and $1.375 per share, respectively.

December 2021 Offering

In December 2021, the Company completed a registered direct offering (the “December 2021 Offering”) of an aggregate of 8,235,297 shares of common stock and 8,235,297 warrants to purchase up to 8,235,297 shares of common stock, at a public offering price of $0.425 per share. The accompanying warrants permit the investor to purchase additional shares equal to the same number of shares of the Company’s common stock purchased by the investor. The warrants have an exercise price of $0.425 per share, may be exercised any time on or after 6 months and one (1) day after the issuance date, and expire five and a half (5.5) years following the date of issuance. In addition, the Company’s placement agent was issued compensatory warrants equal to 5.0%, or 411,765 shares, of the aggregate number of shares of common stock sold in the offering, which are immediately exercisable for an exercise price of $0.5313 and expire five and a half (5.5) years following the date of issuance on June 21, 2027. The Company received gross proceeds of $3.5 million and incurred cash-based placement agent fees and other offering expenses of approximately $0.5 million.

The placement agent warrants, which are recorded as a component of stockholders’ equity, were valued at an aggregate $0.1 million using the Black-Scholes option pricing model based on the following assumptions: expected volatility of 79.81%, risk-free interest rate of 1.21%, expected dividend yield of 0% and an expected term of 5.5 years.

As of March 31, 2022, no warrants associated with the December 2021 Offering have been exercised.

As of March 31, 2022, the Company had 8,235,297 shares and 411,765 shares of common stock reserved for issuance pursuant to the warrants and placement agent’s warrants, respectively, issued by the Company in the December 2021 Offering, at an exercise price of $0.425 per share and $0.5313 per share, respectively.

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Common Stock Purchase Agreement with Lincoln Park

In July 2020, the Company entered into a common stock purchase agreement (the “2020 Purchase Agreement”) with Lincoln Park which provides that, upon the terms and subject to the conditions and limitations in the 2020 Purchase Agreement,  Lincoln Park is committed to purchase up to an aggregate of $10.0 million of shares of the Company’s common stock at the Company’s request from time to time during a 24 month period that began in July 2020 and at prices based on the market price of the Company’s common stock at the time of each sale. Upon execution of the 2020 Purchase Agreement, the Company sold 328,516 shares of common stock at $3.04399 per share to Lincoln Park for gross proceeds of $1.0 million. During the year ended December 31, 2020, the Company sold an additional 300,000 shares of common stock to Lincoln Park for gross proceeds of approximately $0.5 million. In addition, in consideration for entering into the 2020 Purchase Agreement and concurrently with the execution of the 2020 Purchase Agreement, the Company issued 66,964 shares of its common stock to Lincoln Park.  During the three months ended March 31, 2022 the Company did not sell any shares of common stock to Lincoln Park and approximately $8.5 million, or 1.6 million shares of common stock, remains available for sale under the 2020 Purchase Agreement, subject to limitations on the amount of securities the Company may sell under its effective registration statement on Form S-3 within any 12-month period.    

Common Stock Warrants

In 2016, Private Histogen issued warrants to purchase common stock as consideration for settlement of prior liability claims. The warrants for the purchase of up to 3,583 common shares at an exercise price of $23.08 per share expired on July 31, 2021.

In addition, at March 31, 2022, warrants to purchase 1,346 shares of common stock with an exercise price of $74.30 per share remain outstanding that were issued by Conatus in connection with obtaining financing in 2016. These warrants expire on July 3, 2023.

See warrant discussion above in connection with the January 2021 Offering, the June 2021 Offering, and the December 2021 Offering.

Stock-Based Compensation

Equity Incentive Plans

On December 18, 2017, Private Histogen established the Histogen Inc. 2017 Stock Plan (the “2017 Plan”). Under the 2017 Plan, Private Histogen was authorized to issue a maximum aggregate of 837,208 shares of common stock with adjustments for unissued or forfeited shares under the predecessor plan (the Histogen Inc. 2007 Stock Plan). In April 2019, Private Histogen amended the 2017 Plan, which increased the number of common stock available for grants by 326,711 shares. The 2017 Plan permitted the issuance of incentive stock options (“ISOs”), non-statutory stock options (“NSOs”), and Stock Purchase Rights. NSOs could be granted to employees, directors, or consultants, while ISOs could be granted only to employees. Options granted vest over a maximum period of four years and expire ten years from the date of grant. In connection with the closing of the Merger, no further awards will be made under the 2017 Plan.

In May 2020, in connection with the closing of the Merger, the Company’s stockholders approved the Company’s 2020 Incentive Award Plan (the “2020 Plan”). The maximum number of shares of the Company’s common stock available for issuance under the 2020 Plan equals the sum of (a) 850,000 shares; (b) any shares of common stock of the Company which are subject to awards under the Conatus 2013 Equity Incentive Plan (the “Conatus 2013 Plan”) as of the effective date of the 2020 Plan which become available for issuance under the 2020 Plan after such date in accordance with its terms; and (c) an annual increase on the first day of each calendar year beginning with the January 1 of the calendar year following the effectiveness of the 2020 Plan and ending with the last January 1 during the initial ten-year term of the 2020 Plan, equal to the lesser of (i) five percent of the number of shares of the Company’s common stock outstanding (on an as-converted basis) on the final day of the immediately preceding calendar year, and (ii) such lesser number of shares of the Company’s common stock as determined by the Company’s board of directors.

Additionally, in connection with the closing of the Merger, no further awards will be made under the Conatus 2013 Plan. As of March 31, 2022, 97,930 fully vested options remain outstanding under the Conatus 2013 Plan with a weighted average exercise price of $42.90 per share.

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The following summarizes the activity related to the Company’s stock options under the 2017 Plan and the 2020 Plan for the three months ended March 31, 2022:

Prior Chief Executive Officer Stock Options

On January 24, 2019, the Company issued 485,178 stock options to its then newly appointed Chief Executive Officer. In accordance with the original award agreement, 40% of the options would vest immediately upon an initial public offering or 45 days following a change in control, as defined in the award agreement, while the remaining 60% are subject to vesting, of which 25% vest on the first anniversary of the grant date and then ratably over the remaining 36 months.

On January 28, 2020, the award agreement was amended, which became effective upon the close of the Merger in May 2020, whereby the 40% of stock options (“Liquidity Option Shares”) subject to vesting upon an initial public offering or 45 days following a change in control will now vest immediately upon meeting certain performance and market condition-based criteria. The vesting of the Liquidity Option Shares is divided into four separate tranches, each vesting 25% of the Liquidity Option Shares, upon: (1) the closing of the proposed merger with Conatus; (2) the date that the market capitalization of the Company exceeds $200.0 million; (3) the date that the market capitalization of the Company exceeds $275.0 million, and; (4) the date that the market capitalization of the Company exceeds $300.0 million. Each vesting tranche represents a unique derived service period and therefore stock-based compensation expense for each vesting tranche is recognized on a straight-line basis over its respective derived service period. Additionally, in the event that the Chief Executive Officer’s employment with the Company is terminated without cause or he resigns for good reason, an additional portion of the stock options award will vest equal to the number of such options which would have vested in the 12 months following the date of such termination.

On May 26, 2020, in connection with the closing of the Merger, 48,517 options of the Liquidity Option Shares became fully vested as the performance condition was achieved.

In November 2021, the Company’s then President and Chief Executive Officer voluntarily resigned. No further stock-based compensation expense related to the market-based options will be recognized. As of March 31, 2022, the vested option awards expired unexercised.

Board of Directors and Employee Stock Options

In March 2021, in conjunction with a former Board Member’s voluntary resignation, the Company modified share-based payment awards by accelerating the vesting of all awards that were unvested at the time of his voluntary resignation and by extending the exercise period through December 31, 2021. As a result of the modification, the Company recorded an immaterial amount of additional stock-based compensation expense during the year ended December 31, 2021. As of December 31, 2021, the awards expired unexercised.

In June 2021, in conjunction with a former employees’ voluntary resignation, the Company modified share-based payment awards by accelerating the vesting of all awards that were unvested at the time of the voluntary resignation and by extending the exercise period through August 29, 2023.

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Restricted Stock Units

On November 8, 2021, the Company granted 468,449 restricted stock units to the Company’s Interim Chief Executive Officer, Chief Financial Officer, and Senior Vice President of Technical Operations. The fair value of the RSUs was $0.73 per share, which was the closing market price of the Company’s common stock on the date of grant. The RSUs vest in full upon the earlier of (1) 12 months following the grant date and (2) a change of control of the Company, as defined in the Company’s 2020 Plan, and subject to continued service to the Company. In addition, the RSUs awarded to the Company’s Interim Chief Executive Officer are further accelerated in full upon the hiring of a permanent Chief Executive Officer.

The compensation cost that has been included in the accompanying condensed consolidated statements of operations for all stock-based compensation arrangements is detailed as follows (in thousands):

As of March 31, 2022, total unrecognized compensation cost related to unvested options and RSUs was approximately $1.0 million which is expected to be recognized over a weighted-average period of 2.5 years.

8. Commitments and Contingencies

Leases

In January 2020, Private Histogen entered into a long-term operating lease with San Diego Sycamore, LLC (“Sycamore”) for its headquarters which includes office and laboratory space. The lease commenced on March 1, 2020 and expires on August 31, 2031, with no options to renew or extend. The lease was accounted for as a modification of Private Histogen’s existing lease with Sycamore as the lease agreement did not grant Private Histogen an additional right-of-use asset.

The terms of the lease agreement include six months of rent abatement at lease commencement and a tenant improvement allowance of up to $2.2 million. The tenant improvements are required to be permanently affixed to the leased office and laboratory space and do not constitute leasehold improvements of the Company. During the construction period of the tenant improvements, the lease agreement requires the Company to relocate its operations to a similar Sycamore property whereby monthly rent is substantially

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reduced for the duration of the construction period. The lease is subject to additional variable charges for common area maintenance, insurance, taxes, and other operating costs. At lease commencement, the Company recognized a right-of-use asset and operating lease liability totaling approximately $4.5 million. The Company used a discount rate based on its estimated incremental borrowing rate to determine the right-of-use asset and operating lease liability amounts to be recognized. The Company determined its incremental borrowing rate based on the term and lease payments of the new operating lease and what it would normally pay to borrow, on a collateralized basis, over a similar term for an amount equal to the lease payments. Operating lease expense is recognized on a straight-line basis over the lease term. The terms of the lease required the Company to provide the landlord a security deposit of $0.3 million as collateral for a letter of credit issued to be held throughout the lease term. This security deposit is shown as restricted cash on the accompanying consolidated balance sheets.

In June 2021, the Company entered into the First Amendment to Lease (the “Amendment”). Pursuant to the Amendment, among other things, the Company and Sycamore agreed (i) to substitute the temporary premises, (ii) to delay the start of construction and the timing of the Company’s relocation to the replacement temporary premises, (iii) to increase the tenant improvement allowance from $2.2 million to $2.3 million, (iv) to increase the letter of credit amount from $0.3 million to $0.4 million upon commencement of the tenant improvements, and (v) to review potential subsequent reductions to the security deposit and related letter of credit requirement at certain time intervals along the lease term provided that the Company is not in default. As a result of the modification, the lease liability was remeasured using the incremental borrowing rate at the modification date and a corresponding reduction of $0.3 million was recorded to both the lease liability and right-of-use-asset.

In connection with the closing of the Merger, the Company assumed Conatus’ noncancelable operating lease agreement, as amended, for certain office space with a lease term that expired on September 30, 2020. Upon close of the Merger, the Company recognized a right-of-use asset and operating lease liability in the amount of $0.1 million and $0.2 million, respectively, related to the Conatus lease. Prior to the Merger, Conatus entered into a sub-lease agreement with a third party to lease the whole office space for the remainder of the lease term.

The Company leases certain office equipment that is classified as a finance lease. As of March 31, 2022, the weighted-average remaining term of the Company’s operating and finance lease was approximately 9.5 years and 2 years, respectively.

The Company recognizes right-of-use assets and lease liabilities at the lease commencement date based on the present value of future minimum lease payments over the lease term. The discount rate used to determine the present value of the lease payments is the rate implicit in the lease unless that rate cannot be readily determined, in which case, the Company utilizes its incremental borrowing rate in determining the present value of the future minimum lease payments. As of March 31, 2022, the weighted-average discount rate for the Company’s operating and finance lease was 12.2% and 10.0%, respectively.

The Company does not record leases with an initial term of 12 months or less on the consolidated balance sheets. Expense for these short-term leases is recognized on a straight-line basis over the lease term. The Company has elected the practical expedient to combine lease and non-lease components into a single component for all classes of underlying assets.

At March 31, 2022, future minimum payments of lease liabilities were as follows (in thousands):

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PUR Settlement

In April 2019, Private Histogen entered into a Settlement, Release and Termination Agreement (“PUR Settlement”) with PUR Biologics, LLC and its members which terminated the License, Supply and Operating Agreements between Private Histogen and PUR, eliminated Private Histogen’s membership interest in PUR and returned all in-process research and development assets to Private Histogen (the “Development Assets”). The agreement also provided indemnifications and complete releases by and among the parties. The acquisition of the Development Assets was accounted for as an asset acquisition in accordance with ASC 805-50-50, Acquisition of Assets Rather than a Business.

As consideration for the reacquisition of the Development Assets, Private Histogen compensated PUR with both equity and cash components, including 167,323 shares of Series D convertible preferred stock with a fair value of $1.75 million and a potential cash payout of up to $6.25 million (the “Cap Amount”). Private Histogen paid PUR $0.5 million in upfront cash, forgave approximately $22 thousand of accounts receivable owed by PUR to Private Histogen, and settled an outstanding payable of PUR of approximately $23 thousand owed to a third party. The Company is also obligated to make milestone and royalty payments, including (a) a $0.4 million payment upon the unconditional acceptance and approval of a New Drug Application or Pre-Market Approval Application by the FDA related to the Development Assets, (b) a $0.4 million commercialization milestone upon reaching gross sales (by the Company or licensee) of the $0.5 million of products incorporating the Development Assets, and (c) a five percent (5%) royalty on net revenues collected by Histogen from commercial sales (by the Company or licensee) of products incorporating the Development Assets. The aforementioned cash payments, along with any future milestone and royalty payments, are all applied against the Cap Amount. In accordance with authoritative guidance, amounts for the milestone and royalty payments will be recognized when it is probable that the related contingent liability has been incurred and the amount owed is reasonably estimated. No amounts for the milestone and royalty payments have been recorded during the three months ended March 31, 2022 and year ended December 31, 2021.

Litigation and Legal Matters

The Company is subject to claims and legal proceedings that arise in the ordinary course of business. Such matters are inherently uncertain, and there can be no guarantee that the outcome of any such matter will be decided favorably to the Company or that the resolution of any such matter will not have a material adverse effect upon the Company’s condensed consolidated financial statements. The Company accrues a liability for such matters when it is probable that future expenditures will be made, and such expenditures can be reasonably estimated. As of March 31, 2022, no accruals have been made and no liability recognized related to commitments and contingencies.

Employee Litigation

On or about February 17, 2022, two former employees, each of whom separately resigned and terminated their employment with Histogen, filed a complaint in the Superior Court of California, County of San Diego against the Company, the Company’s Board of Directors, the Company’s former Chief Executive Officer, as well as three individuals that are currently employed by the Company. Although the complaint lists the “Histogen Board of Directors, a business entity form unknown” as a defendant, the complaint does not specifically list the names of the board members. The plaintiffs allege whistleblower status, retaliation, discrimination, unfair business practices, wrongful termination, violation of civil rights, and other California state law claims. The Company has tendered the complaint to its liability insurer and engaged outside litigation counsel, as approved by its carrier, to defend Histogen, the Board of Directors and the individuals in this matter. The Company objects to the naming of each of the defendants in this matter and denies each of the plaintiffs’ claims. The plaintiffs agreed to pre-arbitration mediation, which was conducted on May 4, 2022, as was required by the arbitration agreement executed by each of the plaintiffs. Considering that the parties did not resolve the matter through this mediation, the Company expects to petition the San Diego Superior Court for an order that the matter be submitted to arbitration consistent with each of the plaintiff’s arbitration agreements. The Company believes that our defense costs, settlement monies, damages or any other awards would be covered by our liability insurance; provided, however, insurance may not cover all claims or could exceed our insurance coverage. The Company believes that there are substantial defenses to this lawsuit, and we intend to vigorously defend against each of these claims. While this litigation matter is in the early stages, the Company believes the action is without merit. Nonetheless, the ultimate outcome is unknown at this time.

Amerimmune Collaborative Development and Commercialization Agreement

On March 3, 2022, the Company filed a demand for arbitration (“Arbitration Demand”) with JAMS in the county of San Diego, against Amerimmune LLC (“Amerimmune”) seeking a declaratory judgment that Amerimmune has materially breached the Collaborative Agreement entered into by and between the Company and Amerimmune on October 26, 2020, and that Histogen is therefore entitled to terminate the Collaborative Agreement in accordance with its terms. The Company further brought the Arbitration

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Demand for breach of contract, seeking an award of specific performance requiring Amerimmune to comply with the terms of the Agreement, which provide that, in the event of termination for material breach, all rights and licenses granted to Amerimmune by the Company shall terminate, and Amerimmune shall cease any and all development, manufacture and commercialization activities under the Agreement, and any and all rights granted by the Company to Amerimmune revert to Histogen. In the event that specific performance is not awarded, the Company is pursuing in the alternative a cause of action for breach of contract, seeking an award of damages for such breach in an amount to be determined at hearing. And finally, the Company is pursuing a claim for misappropriation of trade secrets, seeking an award of damages in an amount to be determined at hearing.

On March 8, 2022, Amerimmune provided written notice to exercise an option for additional license rights to develop additional products, provided, however, the Company has rejected Amerimmune’s election of the option and believes that Amerimmune no longer has such right to exercise the option based on, amongst other reasons, Histogen’s belief that the Agreement has been terminated as set forth in Histogen’s Arbitration Demand. On March 11, 2022, JAMS issued a Notice of Commencement of Arbitration letter, confirming the commencement of the arbitration as of that date. During the Arbitration, the Company expects Amerimmune and the Company to continue to support planning of a Phase 2 trial of emricasan for the treatment of COVID-19. In the event that the Company is successful on its claims as set forth in the Company’s Arbitration Demand and the Agreement is terminated, the Company intends to develop emricasan for COVID-19 and other infectious and inflammatory diseases independently at its discretion.

There can be no assurances that the Arbitration will result in the Company’s favor. If the Collaborative Agreement is not terminated and the rights granted by the Company to Amerimmune do not revert back to the Company, it is expected that the Company will continue to jointly develop emricasan pursuant to the terms of the Collaborative Agreement. The ultimate outcome of this Arbitration is unknown at this time.

9. Related Parties

Lordship

Lordship, with its predecessor entities along with its principal owner, Jonathan Jackson, have invested and been affiliated with Private Histogen since 2010. As of March 31, 2022 and December 31, 2021, Lordship controlled approximately 4.7% of the Company’s outstanding voting shares and currently holds two Board of Director seats.

In November 2012, Private Histogen entered into a Strategic Relationship Success Fee Agreement with Lordship (the “Success Fee Agreement”). The Success Fee Agreement causes certain payments to be made from the Company to Lordship equal to 1% of certain product revenues and 10% of certain license and royalty revenues. The Success Fee Agreement also stipulates that, if the Company engages in a merger or sale of all or substantially all (defined as 90% or more) of its assets or equity to a third party, then the Company has the option to terminate the agreement by paying Lordship the fair market value of future payments with the minimum payment being at least equal to the most recent annual payments Lordship has received. The Success Fee Agreement was amended in August 2016, but continues to carry the same rights to certain payments. Histogen recognized an expense to Lordship for the three months ended March 31, 2022 and 2021 totaling $0.4 million and $3 thousand, respectively, all of which is included in general and administrative expenses on the accompanying consolidated statements of operations. As of March 31, 2022 and December 31, 2021, there was a balance of $11 thousand and $12 thousand, respectively, paid to Lordship included in other assets on the accompanying condensed consolidated balance sheet in connection with the deferral of revenue from the Allergan License Agreements.

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