Document and Entity Information
Document and Entity Information - shares | 9 Months Ended | |
Sep. 30, 2023 | Nov. 09, 2023 | |
Cover [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Sep. 30, 2023 | |
Document Fiscal Year Focus | 2023 | |
Document Fiscal Period Focus | Q3 | |
Trading Symbol | HSTO | |
Entity Registrant Name | Histogen Inc. | |
Entity Central Index Key | 0001383701 | |
Entity Current Reporting Status | Yes | |
Entity Interactive Data Current | Yes | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Non-accelerated Filer | |
Entity Shell Company | true | |
Entity Small Business | true | |
Entity Emerging Growth Company | false | |
Title of 12(b) Security | Common Stock, $0.0001 par value | |
Entity Incorporation, State or Country Code | DE | |
Entity Address, Address Line One | 10655 Sorrento Valley Road | |
Entity Address, Address Line Two | Suite 200 | |
Entity Address, City or Town | San Diego | |
Entity Address, State or Province | CA | |
Entity Address, Postal Zip Code | 92121 | |
City Area Code | (858) | |
Local Phone Number | 526-3100 | |
Entity File Number | 001-36003 | |
Entity Tax Identification Number | 20-3183915 | |
Entity Common Stock, Shares Outstanding | 4,271,759 | |
Document Quarterly Report | true | |
Document Transition Report | false |
CONDENSED CONSOLIDATED BALANCE
CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) | Sep. 30, 2023 | Dec. 31, 2022 |
Current assets | ||
Cash and cash equivalents | $ 4,573,000 | $ 12,109,000 |
Restricted cash | 300,000 | 400,000 |
Accounts receivable, net | 0 | 99,000 |
Prepaid and other current assets | 582,000 | 848,000 |
Total current assets | 5,455,000 | 13,456,000 |
Property and equipment, net | 0 | 436,000 |
Right-of-use asset | 4,658,000 | |
Other assets | 362,000 | 523,000 |
Total assets | 5,817,000 | 19,073,000 |
Current liabilities | ||
Accounts payable | 386,000 | 382,000 |
Accrued liabilities | 943,000 | 595,000 |
Current portion of lease liabilities | 238,000 | |
Current portion of deferred revenue | 19,000 | 19,000 |
Total current liabilities | 1,348,000 | 1,234,000 |
Lease liabilities, non-current | 4,379,000 | |
Deferred revenue, non-current | 65,000 | 79,000 |
Finance lease liability, non-current | 5,000 | |
Total liabilities | 1,413,000 | 5,697,000 |
Commitments and contingencies (Note 8) | ||
Stockholders' equity | ||
Preferred stock, $0.0001 par value; 10,000,000 shares authorized at September 30, 2023 and December 31, 2022; no shares issued and outstanding at September 30, 2023 and December 31, 2022 | ||
Common stock, $0.0001 par value; 200,000,000 shares authorized at September 30, 2023 and December 31, 2022; 4,271,759 shares issued and outstanding at September 30, 2023 and December 31, 2022 | 5,000 | 5,000 |
Additional paid-in capital | 103,117,000 | 102,673,000 |
Accumulated deficit | (97,686,000) | (88,273,000) |
Total Histogen, Inc. stockholders' equity | 5,436,000 | 14,405,000 |
Noncontrolling interest | (1,032,000) | (1,029,000) |
Total equity | 4,404,000 | 13,376,000 |
Total liabilities and stockholders’ equity | $ 5,817,000 | $ 19,073,000 |
CONDENSED CONSOLIDATED BALANC_2
CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares | Sep. 30, 2023 | Dec. 31, 2022 |
Statement of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.0001 | $ 0.0001 |
Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.0001 | $ 0.0001 |
Common stock, shares authorized | 200,000,000 | 200,000,000 |
Common stock, shares issued | 4,271,759 | 4,271,759 |
Common stock, shares outstanding | 4,271,759 | 4,271,759 |
UNAUDITED CONDENSED CONSOLIDATE
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | ||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | |
Revenue | ||||
Total revenue | $ 5 | $ 5 | $ 15 | $ 3,765 |
Operating expense | ||||
Research and development | 660 | 907 | 2,189 | 3,932 |
General and administrative | 2,870 | 2,696 | 6,913 | 7,508 |
Total operating expense | 3,530 | 3,603 | 9,102 | 11,440 |
Loss from operations | (3,525) | (3,598) | (9,087) | (7,675) |
Other income (expense) | ||||
Interest expense, net | (1) | (1) | (2) | |
Other income (expense) | (5) | (5) | ||
Gain on sale of subsidiary | 1 | |||
Loss on disposal of fixed assets | (324) | (324) | ||
Net loss | (3,854) | (3,599) | (9,416) | (7,677) |
Loss (gain) attributable to noncontrolling interest | 3 | 3 | 3 | 20 |
Deemed dividend - accretion of discount and redemption feature of redeemable convertible preferred stock | (488) | |||
Net loss available to common stockholders | $ (3,851) | $ (3,596) | $ (9,413) | $ (8,145) |
Net loss per share available to common stockholders, basic | $ (0.90) | $ (1.01) | $ (2.20) | $ (2.85) |
Net loss per share available to common stockholders, diluted | $ (0.90) | $ (1.01) | $ (2.20) | $ (2.85) |
Weighted-average number of common shares outstanding used to compute net loss per share, basic | 4,271,759 | 3,554,623 | 4,271,759 | 2,853,713 |
Weighted-average number of common shares outstanding used to compute net loss per share, diluted | 4,271,759 | 3,554,623 | 4,271,759 | 2,853,713 |
License [Member] | ||||
Revenue | ||||
Total revenue | $ 5 | $ 5 | $ 15 | $ 3,765 |
UNAUDITED CONDENSED CONSOLIDA_2
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands | Total | Redeemable Convertible Preferred Stock [Member] | Common Stock [Member] | Additional Paid-in Capital [Member] | Accumulated Deficit [Member] | Total Histogen, Inc. Stockholders' Equity (Deficit) [Member] | Noncontrolling Interest [Member] |
Beginning balance at Dec. 31, 2021 | $ 20,186 | $ 5 | $ 98,839 | $ (77,652) | $ 21,192 | $ (1,006) | |
Beginning balance, shares at Dec. 31, 2021 | 2,497,450 | ||||||
Issuance of common stock, net of issuance costs | (9) | (9) | (9) | ||||
Issuance of redeemable convertible preferred stock, net of issuance costs | $ 4,296 | ||||||
Issuance of redeemable convertible preferred stock, net of issuance costs, shares | 5,000 | ||||||
Stock-based compensation expense | 165 | 165 | 165 | ||||
Net loss | (684) | (673) | (673) | (11) | |||
Ending balance at Mar. 31, 2022 | 19,658 | $ 5 | 98,995 | (78,325) | 20,675 | (1,017) | |
Ending balance, shares at Mar. 31, 2022 | 2,497,450 | ||||||
Ending balance at Mar. 31, 2022 | $ 4,296 | ||||||
Ending balance, shares at Mar. 31, 2022 | 5,000 | ||||||
Beginning balance at Dec. 31, 2021 | 20,186 | $ 5 | 98,839 | (77,652) | 21,192 | (1,006) | |
Beginning balance, shares at Dec. 31, 2021 | 2,497,450 | ||||||
Net loss | (7,677) | ||||||
Ending balance at Sep. 30, 2022 | 16,254 | $ 5 | 102,584 | (85,309) | 17,280 | (1,026) | |
Ending balance, shares at Sep. 30, 2022 | 4,271,759 | ||||||
Beginning balance at Mar. 31, 2022 | 19,658 | $ 5 | 98,995 | (78,325) | 20,675 | (1,017) | |
Beginning balance, shares at Mar. 31, 2022 | 2,497,450 | ||||||
Issuance of redeemable convertible preferred stock, net ofissuance costs | (119) | (119) | (119) | ||||
Accretion of issuance costs, discount and redemption feature of redeemable convertible preferred stock | (954) | $ 954 | (954) | (954) | |||
Redemption of redeemable convertible preferred stock, shares | (5,000) | ||||||
Redemption of redeemable convertible preferred stock | $ (5,250) | ||||||
Stock-based compensation expense | 115 | 115 | 115 | ||||
Net loss | (3,394) | (3,388) | (3,388) | (6) | |||
Ending balance at Jun. 30, 2022 | 15,306 | $ 5 | 98,037 | (81,713) | 16,329 | (1,023) | |
Ending balance, shares at Jun. 30, 2022 | 2,497,450 | ||||||
Issuance of common stock, net of issuance costs | 4,414 | 4,414 | 4,414 | ||||
Issuance of common stock, net of issuance costs, shares | 1,774,309 | ||||||
Stock-based compensation expense | 133 | 133 | 133 | ||||
Net loss | (3,599) | (3,596) | (3,596) | (3) | |||
Ending balance at Sep. 30, 2022 | 16,254 | $ 5 | 102,584 | (85,309) | 17,280 | (1,026) | |
Ending balance, shares at Sep. 30, 2022 | 4,271,759 | ||||||
Beginning balance at Dec. 31, 2022 | 13,376 | $ 5 | 102,673 | (88,273) | 14,405 | (1,029) | |
Beginning balance, shares at Dec. 31, 2022 | 4,271,759 | ||||||
Stock-based compensation expense | 419 | 419 | 419 | ||||
Net loss | (3,473) | (3,470) | (3,470) | (3) | |||
Ending balance at Mar. 31, 2023 | 10,322 | $ 5 | 103,092 | (91,743) | 11,354 | (1,032) | |
Ending balance, shares at Mar. 31, 2023 | 4,271,759 | ||||||
Beginning balance at Dec. 31, 2022 | 13,376 | $ 5 | 102,673 | (88,273) | 14,405 | (1,029) | |
Beginning balance, shares at Dec. 31, 2022 | 4,271,759 | ||||||
Net loss | (9,416) | ||||||
Ending balance at Sep. 30, 2023 | 4,404 | $ 5 | 103,117 | (97,686) | 5,436 | (1,032) | |
Ending balance, shares at Sep. 30, 2023 | 4,271,759 | ||||||
Beginning balance at Mar. 31, 2023 | 10,322 | $ 5 | 103,092 | (91,743) | 11,354 | (1,032) | |
Beginning balance, shares at Mar. 31, 2023 | 4,271,759 | ||||||
Stock-based compensation expense | 32 | 32 | 32 | ||||
Net loss | (2,089) | (2,092) | (2,092) | 3 | |||
Ending balance at Jun. 30, 2023 | 8,265 | $ 5 | 103,124 | (93,835) | 9,294 | (1,029) | |
Ending balance, shares at Jun. 30, 2023 | 4,271,759 | ||||||
Stock-based compensation expense | (7) | (7) | (7) | ||||
Net loss | (3,854) | (3,851) | (3,851) | (3) | |||
Ending balance at Sep. 30, 2023 | $ 4,404 | $ 5 | $ 103,117 | $ (97,686) | $ 5,436 | $ (1,032) | |
Ending balance, shares at Sep. 30, 2023 | 4,271,759 |
UNAUDITED CONDENSED CONSOLIDA_3
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands | 3 Months Ended | 9 Months Ended | |
Sep. 30, 2023 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | |
Cash flows from operating activities | |||
Net loss | $ (3,854) | $ (9,416) | $ (7,677) |
Adjustments to reconcile net loss to net cash used in operating activities: | |||
Depreciation and amortization | 100 | 102 | |
Stock-based compensation | 444 | 413 | |
Gain from sale of subsidiary | (1) | ||
Loss on disposal of fixed assets | 324 | 324 | |
Changes in operating assets and liabilities: | |||
Accounts receivable | 99 | 91 | |
Prepaid expenses and other current assets | 266 | 655 | |
Other assets | 162 | 167 | |
Accounts payable | 4 | (832) | |
Accrued liabilities | 357 | (198) | |
Right-of-use asset and lease liabilities, net | 41 | 49 | |
Deferred revenue | (15) | (14) | |
Net cash used in operating activities | (7,635) | (7,244) | |
Cash flows from investing activities | |||
Cash proceeds from sale of subsidiary | 1 | ||
Cash paid for property and equipment | (215) | ||
Cash proceeds from sale of property and equipment | 12 | ||
Net cash provided by (used in) investing activities | 13 | (215) | |
Cash flows from financing activities | |||
Proceeds from the issuance of common stock, net of issuance costs | 4,414 | ||
Costs paid in connection with December 2021 financing | (9) | ||
Repayment of finance lease obligations | (14) | (6) | |
Issuance costs for redeemable convertible preferred stock | (585) | ||
Redemption payment for redeemable convertible preferred stock | (488) | ||
Net cash (used in) provided by financing activities | (14) | 3,326 | |
Net decrease in cash, cash equivalents and restricted cash | (7,636) | (4,133) | |
Cash, cash equivalents and restricted cash, beginning of period | 12,509 | 19,085 | |
Cash, cash equivalents and restricted cash, end of period | 4,873 | 4,873 | 14,952 |
Reconciliation of cash, cash equivalents and restricted cash to the condensed consolidated balance sheets | |||
Cash and cash equivalents | 4,573 | 4,573 | 14,552 |
Restricted cash | 300 | 300 | 400 |
Total cash, cash equivalents and restricted cash | $ 4,873 | 4,873 | 14,952 |
Supplemental disclosure of cash flow information | |||
Cash paid for interest | $ 1 | 1 | |
Noncash investing and financing activities | |||
Redemption payment of redeemable convertible preferred stock from escrow | (4,762) | ||
Issuance of redeemable convertible preferred stock, proceeds held in escrow | 4,762 | ||
Fair value of warrants issued to Placement Agent | $ 283 |
Insider Trading Arrangements
Insider Trading Arrangements | 3 Months Ended |
Sep. 30, 2023 | |
Trading Arrangements, by Individual | |
Rule 10b5-1 Arrangement Adopted | false |
Non-Rule 10b5-1 Arrangement Adopted | false |
Rule 10b5-1 Arrangement Terminated | false |
Non-Rule 10b5-1 Arrangement Terminated | false |
Description of Business and Bas
Description of Business and Basis of Presentation | 9 Months Ended |
Sep. 30, 2023 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Description of Business and Basis of Presentation | 1. Description of Business and Basis of Presentation 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. Until recently, the Company was a clinical-stage therapeutics company focused on developing potential first-in-class clinical and preclinical small molecule pan-caspase and caspase selective inhibitors that protect the body’s natural process to restore immune function. 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 (“Nasdaq”) under the ticker symbol “HSTO”. On September 18, 2023, the Company announced, after extensive consideration of potential strategic alternatives, that its Board of Directors (the “Board”), had unanimously approved the dissolution and liquidation of Histogen (the “Dissolution”) pursuant to a plan of complete liquidation and dissolution (the “Plan of Dissolution”), subject to stockholder approval. In connection with the Plan of Dissolution, the Company discontinued all development programs and terminated all but two employees as of September 30, 2023. The focus of the remaining two employees is to manage the wind-down of the Company's operations and matters related to managing the Dissolution, including obtaining the necessary stockholder approval of the Plan of Dissolution. Additionally, the Company is currently seeking to sell their caspase program assets and other remaining assets. In light of the planned dissolution, on September 26, 2023, the Company received written notice from Nasdaq advising the Company that based upon Nasdaq’s review and pursuant to Listing Rule 5101, Nasdaq believed that the Company is a “public shell,” and that the continued listing of our securities was no longer warranted. As a result, the trading of the Company's common stock was suspended as of the opening of business on October 5, 2023, and on October 12, 2023, Nasdaq filed a Form 25-NSE with the Securities and Exchange Commission (“SEC”), which removed the Company's common stock from listing and registration on Nasdaq. Recent Developments On October 3, 2023, the Company entered into an Asset Purchase Agreement (the “Asset Purchase Agreement”) with Allergan Sales, LLC (“Allergan”), pursuant to which Histogen and its affiliates sold to Allergan certain assets, including certain patents and other intellectual property rights, related to Histogen’s hypoxia generated growth factor technology (the “Transaction”). In exchange, Allergan agreed to pay Histogen a purchase price of $ 2.1 million and agreed to assume certain liabilities as set forth in the Asset Purchase Agreement. The Asset Purchase Agreement contains customary provisions on, among other things, representation and warranties, and covenants related to the transfer of ownership of the acquired assets and other matters. In connection with the Transaction, on October 3, 2023, the Company and Allergan mutually elected to terminate the Allergan License Agreements, as amended from time to time. In connection with the Transaction, on October 3, 2023, the Company also entered into a Mutual Termination of the Second Amended and Restated Strategic Relationship Success Fee Agreement (the “Lordship Agreement’) with Lordship Ventures LLC (“Lordship”), pursuant to which Histogen agreed to pay Lordship a mutually agreed to success and termination fee as required by the terms of the Lordship Agreement (refer to Note 10 for further information). Reverse Stock Split On June 2, 2022, the Company’s Board approved a one-for- twenty reverse stock split of its then outstanding common stock (the “Reverse Stock Split”) with any fractional shares resulting from the Reserve Stock Split rounded down to the next whole share of common stock. The par value and the authorized shares of the common stock were not adjusted as a result of the Reverse Stock Split. All references to share and per share amounts for all periods presented in the condensed consolidated financial statements have been retrospectively restated to reflect this Reverse Stock Split. Additionally, all rights to receive shares of common stock under outstanding warrants, options, and restricted stock units (“RSUs”) were adjusted to give effect of the reverse stock split. Furthermore, remaining shares of common stock available for future issuance under stock-based payment award plans and employee stock purchase plans were adjusted to give effect to the Reverse Stock Split. Liquidity and Going Concern The Company has incurred operating losses and negative cash flows from operations and had an accumulated deficit of $ 97.7 million as of September 30, 2023. The Company expects operating losses and negative cash flows from operations to continue for the foreseeable future, including through the execution of the Plan of Dissolution if approved by the Company’s stockholders. In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that these consolidated financial statements are issued on November 9, 2023. The Company has determined that its cash and cash equivalents as of September 30, 2023 of $ 4.6 million would be insufficient to fund its operations for a period of at least twelve months from the date of these financial statements which raises substantial doubt regarding the Company’s ability to continue as a going concern. The Company does not have plans to alleviate the substantial doubt about the Company’s ability to continue as a going concern. On September 18, 2023, the Company announced that the Board unanimously approved the Plan of Dissolution. As the Plan of Dissolution has not yet been brought to a vote or approved by the Company’s stockholders, the Company concluded that the liquidation basis of accounting should not be applied as of the balance sheet date. Accordingly, the accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The condensed consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from the outcome of these uncertainties described above. 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 accounting principles generally accepted in the United States (“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 was a wholly-owned subsidiary intended to pursue registration with the COFEPRIS (Mexico equivalent to Food and Drug Administration). Since the Company acquired CIMRESA in 2018, there have been no financial or operational activities. On January 17, 2023, the Company sold the wholly-owned subsidiary, CIMRESA, and deconsolidated the former subsidiary, resulting in a gain during the nine months ended September 30, 2023. 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 (refer to Note 2 for further information). Unaudited Interim Financial Information The unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2023 and 2022 have been prepared in accordance with the rules and regulations of the 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, 2022 included in the Annual Report on Form 10-K that the Company filed with the SEC on March 9, 2023. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 9 Months Ended |
Sep. 30, 2023 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies 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 to the business and operating results presents additional uncertainty, the Company continues to use the best information available to them in their significant accounting estimates. Significant estimates and assumptions include those related to the useful lives of property and equipment, discount rates used in recognizing contracts containing leases, unrecognized tax benefits, and volatility used for stock-based compensation option pricing. 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 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. Customer Risk During the three and nine months ended September 30, 2023 and 2022 , one customer accounted for 100 % of total revenues. Accounts Receivable Accounts receivable are generally due within 30 days and are recorded net of the allowance for doubtful accounts, if any. Management considers all accounts receivable to be recoverable, and accordingly, no provision for doubtful accounts was recorded at December 31, 2022. No accounts receivable are recorded as of September 30, 2023 on the accompanying condensed consolidated balance sheets. 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. No property and equipment are recorded as of September 30, 2023 on the accompanying condensed consolidated balance sheets. 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. During the three months ended September 30, 2023, the Company disposed of its remaining property and equipment and, as of September 30, 2023 , other assets are the remaining long-lived assets recorded on the accompanying condensed consolidated balance sheets (refer to Note 4 for further information). Comprehensive Loss The Company is required to report all components of comprehensive loss, including net loss, in the accompanying condensed consolidated financial statements in the period in which they are recognized. Comprehensive loss is defined as 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 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. The Company applies the revenue recognition standard, including the use of any practical expedients, consistently to contracts with similar characteristics and in similar circumstances (refer to Note 5 for further information). Grant Awards 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 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 and nine months ended September 30, 2023, qualifying expenses totaling $ 0 and $ 0.1 million have been incurred with a corresponding reduction of research and development expenses related to the award, respectively. As of September 30, 2023 and December 31, 2022, $ 0 and $ 0.1 million was included in accounts receivable within the condensed consolidated balance sheets with respect to the award, respectively. The Company made the decision in December 2022 to terminate the study for futility regarding patient recruitment and redirect efforts and funding away from HST-003 to other product candidates. As of March 31, 2023, the Company had completed its HST-003 clinical study close-out activities and early terminated the grant award. 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, 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 consist of professional fees for legal (including patent costs), audit and other consulting services, travel and entertainment, recruiting, facility costs, 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 as a component of general and administrative expenses in the accompanying 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 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 and nine months ended September 30, 2023 and 2022, 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. For the three and nine months ended September 30, 2023 and 2022, diluted net loss per share attributable to common stockholders is equal to 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): September 30, 2023 September 30, 2022 Common stock options issued and outstanding 218,919 129,006 Warrants to purchase common stock 4,876,571 4,876,639 Total anti-dilutive shares 5,095,490 5,005,645 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. Recently Issued Accounting Pronouncements Not Yet Adopted In March 2023, the FASB issued ASU No. 2023-01, Leases (Topic 842): Common Control Arrangements (“ASU 2023-01” ), amending certain provisions of ASC 842 that apply to arrangements between related parties under common control. This standard amends the accounting for leasehold improvements in common-control arrangements for all entities. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, with early adoption permitted. The Company does not expect to early adopt this guidance and is in the process of evaluating the impact of adoption of this guidance on the Company’s consolidated financial statements. Recently Adopted Accounting Pronouncements None. |
Property and Equipment, Net
Property and Equipment, Net | 9 Months Ended |
Sep. 30, 2023 | |
Property, Plant and Equipment [Abstract] | |
Property and Equipment, Net | 3. Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): September 30, December 31, Lab and manufacturing equipment $ — $ 937 Office furniture and equipment — 225 Software — 48 Total — 1,210 Less: accumulated depreciation and amortization — ( 774 ) Property and equipment, net $ — $ 436 Depreciation and amortization expense for the nine months ended September 30, 2023 and 2022 , were $ 100 t housand and $ 102 thousand, respectively. During the three months ended September 30, 2023, the Company disposed of $ 1.2 million in property and equipment that had an accumulated depreciation of $ 0.9 million, resulting in a loss of $ 0.3 million on the accompanying condensed consolidated statements of operations. |
Balance Sheet Details
Balance Sheet Details | 9 Months Ended |
Sep. 30, 2023 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Balance Sheet Details | 4. Balance Sheet Details Prepaid and other current assets consisted of the following (in thousands): September 30, December 31, Insurance $ 463 $ 626 Prepaid rent — 81 Pre-clinical and clinical related expenses — 64 Prepaid corporate taxes 79 — Other 40 77 Total $ 582 $ 848 Other assets consisted of the following (in thousands): September 30, December 31, Insurance $ 353 $ 513 Other 9 10 Total $ 362 $ 523 Accrued liabilities consisted of the following (in thousands): September 30, December 31, Current portion of finance lease liabilities $ — $ 9 Accrued compensation 787 160 Preclinical and clinical related expenses — 150 Legal fees 134 44 Accrued franchise tax — 162 Other 22 70 Total $ 943 $ 595 |
Revenues
Revenues | 9 Months Ended |
Sep. 30, 2023 | |
Revenue from Contract with Customer [Abstract] | |
Revenues | 5. Revenues The following is a summary description of the material revenue arrangements, including arrangements that generated revenues during the three and nine months ended September 30, 2023 and 2022. 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 the Company’s cell conditioned medium (“CCM”) skin care ingredient in the medical aesthetics market to 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, the Company 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, the Company 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. 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 life of the patent into early 2028. 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. 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. All deliveries of Additional Supply of CCM to Allergan have been completed as of March 31, 2021. As such, there is no revenue for the three and nine months ended September 30, 2023 and 2022. Revenue of $ 0.2 million related to the Potential Future Improvements has been deferred and amortized ratably over the remaining life of the patent into early 2028, for which $ 5 thousand and $ 15 thousand of previously deferred revenue was recognized in revenue during each of the three and nine months ended September 30, 2023 and 2022, respectively. 2022 Allergan Letter Agreement Pursuant to the 2017 Allergan Amendment, the Company 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 Allergan. In consideration for the execution of the Letter Agreement, the Company 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 applied point in time recognition. The Company recognized the entire $ 3.8 million of license revenue related to the Letter Agreement during the year ended December 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 both September 30, 2023 and December 31, 2022. Deferred revenue is classified in current portion of deferred revenue liabilities when the Company’s obligations to provide research for Potential Future Improvements are expected to be satisfied within twelve months of the balance sheet date. The deferred revenue is recognized on a straight-line basis over the remaining life of the licensing patents into early 2028. |
Redeemable Convertible Preferre
Redeemable Convertible Preferred Stock | 9 Months Ended |
Sep. 30, 2023 | |
Equity [Abstract] | |
Redeemable Convertible Preferred Stock | 6. Redeemable Convertible Preferred Stock The redeemable convertible preferred stock instruments were contingently redeemable preferred stock. Each series contained redemption features, limited voting rights, dividends, and conversion terms. The convertible preferred stock was presented on the consolidated balance sheets as mezzanine equity as of March 31, 2022. All shares of redeemable convertible preferred stock were fully redeemed and were no longer outstanding as of June 30, 2022. 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 had a stated value of $ 1,000 per share and were convertible, at a conversion price of $ 20.00 per share, into 125,000 shares of common stock. The shares of Series B Preferred Stock had a stated value of $ 1,000 per share and were convertible, at a conversion price of $ 20.00 per share, into 125,000 shares of common stock. The closing occurred on March 25, 2022 . The proceeds of $ 4.76 million were held in escrow and were only permitted to be disbursed to the Company upon conversion of the Series A and Series B Preferred Stock. Since the redeemable convertible preferred stock could have been redeemed at the option of the holder, but was not mandatorily redeemable, the redeemable preferred stock was classified as mezzanine equity and initially recognized at fair value of $ 4.76 million as mezzanine equity on the accompanying statement of redeemable convertible preferred stock and stockholders' equity. 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 $ 0.6 million. The proceeds were held in escrow and were only permitted to be disbursed to the Company upon conversion of the Series A and Series B Preferred Stock. 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 17,501 shares of common stock, with an exercise price of 125 % of the offering price, or $ 25.00 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 stockholders’ 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 September 30, 2023, the Company had 17,501 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 $ 25.00 per share. Voting Rights The shares of Preferred Stock had 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 the Company's certificate of incorporation to effect a reverse stock split of issued and outstanding common stock within a range, to be determined by the Board and set forth in such proposal. Each share of Series A Preferred Stock outstanding on April 14, 2022 (the “Record Date”) had 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 had 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 of the Series A Preferred Stock agreed to not transfer their shares of Series A Preferred Stock until after the 2022 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 entitled the holder thereof to cast 30,000 votes on the Reverse Stock Split Proposal. The holders of the Series B Preferred Stock agreed to not transfer their shares of Series B Preferred Stock until after the 2022 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 were 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 were voted against such Proposal, then 70 % of the votes entitled to be cast by Series B Preferred Stock would have been cast in favor of the proposal and 30 % of such votes would have been cast against the proposal. Dividends The holders of the redeemable convertible preferred stock were 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 were payable on shares of Preferred Stock. Conversion Rights Each share of Preferred Stock was 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 had a stated value of $ 1,000 per share and were convertible, at a conversion price of $ 20.00 per share, into 125,000 shares of common stock. The shares of Series B Preferred Stock had a stated value of $ 1,000 per share and were convertible, at a conversion price of $ 20.00 per share, into 125,000 shares of common stock. Redemption Rights Each share of Preferred Stock was redeemable after (i) the earlier of (1) the receipt of authorized stockholder approval for the reverse stock split and (2) the date that was 90 days following the Original Issue Date of March 25, 2022, and (ii) before the date that was 120 days after the Original Issue Date or July 23, 2022 (the “Redemption Period”) , each stockholder had 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. Between June 2, 2022, and June 29, 2022, at the request of the holders, the Company redeemed for cash proceeds totaling $ 5.25 million ($ 4.76 million payment from escrow and $ 0.5 million redemption payment by the Company), 2,500 outstanding shares of Series A Preferred Stock and 2,500 outstanding shares of Series B Preferred Stock based on the receipt of the Redemption Notices (the “Preferred Redemption”) at a price equal to 105 % of the $ 1,000 stated value per share, which represented all outstanding shares of Preferred Stock. The approximately $ 1.1 million accretion of the Series A and Series B Preferred Stock to its redemption value was recorded as a reduction to additional paid-in capital. The Company recognized a portion of the accretion as a deemed dividend related to the accretion of the discount and redemption feature of approximately $ 0.5 million upon redemption of Preferred Stock on the consolidated statement of operations. On June 30, 2022, the Company filed a Certificate of Elimination with respect to the Series A Preferred Stock and Series B Preferred Stock (the “Series A Certificate of Elimination and the Series B Certificate of Elimination”), which upon filing with the Secretary of State of the State of Delaware (“Delaware Secretary”), eliminated from all matters set forth in the Certificates of Designation of Series A and Series B Preferred Stock. As of September 30, 2023 and December 31, 2022 , all shares of the Series A Preferred Stock and Series B Preferred Stock are no longer outstanding and the Company’s only remaining class of outstanding stock is its common stock, par value $ 0.0001 per share. |
Stockholders' Equity
Stockholders' Equity | 9 Months Ended |
Sep. 30, 2023 | |
Equity [Abstract] | |
Stockholders' Equity | 7. Stockholders’ Equity Common Stock January 2021 Offering In January 2021, the Company completed an S-1 offering (the “January 2021 Offering”) of an aggregate of 580,000 shares of common stock, pre-funded warrants to purchase up to 120,000 shares of its common stock, and common stock warrants to purchase up to an aggregate of 700,000 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 stock 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 stock 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 $ 20.00 , and the combined purchase price of one pre-funded warrant and accompanying common stock warrant was $ 19.998 . The common stock warrants are exercisable for five ( 5 ) years at an exercise price of $ 20.00 per share. The pre-funded warrants were immediately exercisable at an exercise price of $ 0.002 per share and were exercisable at any time until all of the pre-funded warrants are exercised in full. Placement agent warrants were issued to purchase up to 35,000 shares of common stock, are immediately exercisable for an exercise price of $ 25.00 per share, 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. The common stock 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 September 30, 2023, a total of 336,060 warrants issued in the January 2021 Offering to purchase shares of common stock have been exercised and the Company issued 336,060 shares of its common stock. The Company received gross proceeds of approximately $ 6.8 million. As of September 30, 2023 , the Company had 387,565 shares and 11,375 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 $ 20.00 per share and $ 25.00 per share, respectively. June 2021 Offering In June 2021, the Company completed a registered direct offering (the “June 2021 Offering”) of an aggregate of 298,865 shares of common stock, together with accompanying warrants to purchase up to an aggregate of 239,093 shares of common stock, at a public offering price of $ 22.00 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 $ 20.00 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 14,946 shares, of the aggregate number of common stock sold in the offering, which are immediately exercisable for an exercise price of $ 27.50 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 September 30, 2023, no warrants associated with the June 2021 Offering have been exercised. As of September 30, 2023 , the Company had 90,910 shares and 14,946 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 $ 20.00 per share and $ 27.50 per share, respectively. In connection with the July 2022 Offering, the Company agreed to amend warrants, by reducing the exercise price and extending the expiration date, to purchase up to an aggregate of 148,183 shares of common stock of the Company that were originally issued to the investor in the June 2021 Offering. Refer to July 2022 Offering overview below for accounting treatment for the amended warrants. December 2021 Offering In December 2021, the Company completed a registered direct offering (the “December 2021 Offering”) of an aggregate of 411,764 shares of common stock and 411,766 warrants to purchase up to 411,766 shares of common stock, at a public offering price of $ 8.50 per share. The accompanying warrants permit the investor to purchase additional shares equal to approximately the same number of shares of the Company’s common stock purchased by the investor. The warrants have an exercise price of $ 8.50 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 20,590 shares, of the aggregate number of shares of common stock sold in the offering, which are immediately exercisable for an exercise price of $ 10.626 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 September 30, 2023 , no warrants associated with the December 2021 Offering have been exercised. As of September 30, 2023 , the Company had 164,707 shares and 20,590 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 $ 8.50 per share and $ 10.626 per share, respectively. In connection with the July 2022 Offering, the Company agreed to amend warrants, by reducing the exercise price and extending the expiration date, to purchase up to an aggregate of 247,059 shares of common stock of the Company that were originally issued to the investor in the December 2021 Offering. Refer to July 2022 Offering overview below for accounting treatment for the amended warrants. July 2022 Offering On July 12, 2022, the Company entered into a Securities Purchase Agreement (the “July 2022 Purchase Agreement”) with a single healthcare-focused institutional investor for the sale by the Company of (i) a pre-funded warrant to purchase up to 1,774,309 shares of Common Stock (the “Pre-Funded Warrant”), (ii) a Series A warrant to purchase up to an aggregate of 1,774,309 shares of common stock (the “Series A Warrant”), and (iii) a Series B warrant to purchase up to an aggregate of 1,774,309 shares of common stock (the “Series B Warrant,” and together with the Pre-Funded Warrant and the Series A Warrant, the “Warrants”), in a private placement offering (the “Offering”). The combined purchase price of one Pre-Funded Warrant and accompanying Series A Warrant and accompanying Series B Warrant was $ 2.818 . Subject to certain ownership limitations, the Series A Warrant became exercisable immediately after the issuance date at an exercise price equal to $ 2.568 per share of common stock, subject to adjustments as provided under the terms of the Series A Warrant, and has a term of five and a half ( 5.5 ) years from the issuance date. Subject to certain ownership limitations, the Series B Warrant became exercisable immediately after the issuance date at an exercise price equal to $ 2.568 per share of common stock, subject to adjustments as provided under the terms of the Series B Warrant, and has a term of one and a half ( 1.5 ) years from the issuance date. Subject to certain ownership limitations described in the Pre-Funded Warrant, the Pre-Funded Warrant was immediately exercisable at an exercise price of $ 0.0001 per share of common stock any time until all of the Pre-Funded Warrant is exercised in full. As of September 30, 2023 , the Pre-Funded Warrant to purchase up to an aggregate of 1,774,309 shares of common stock had been fully exercised and the Company issued 1,774,309 shares of common stock. The Company also agreed to amend certain warrants to purchase up to an aggregate of 447,800 shares of common stock of the Company that were issued to the investor in the private placement in November 2020, June 2021 and December 2021 with exercise prices ranging from $ 8.50 to $ 34.00 per share and expiration dates ranging from May 18, 2026 to June 21, 2027 , so that such warrants have a reduced exercise price of $ 2.568 per share and expiration date of five and a half ( 5.5 ) years following the closing of the private placement, for an additional offering price of $ 0.0316 per amended warrant. The incremental fair value resulting from the modifications to the warrants was adjusted against the gross proceeds from the offering as an equity issuance cost. The gross proceeds to the Company were approximately $ 5 million, before deducting the placement agent’s fees and other offering expenses, and excluding the proceeds, if any, from the exercise of the Series A Warrant, the Series B Warrant, and amended warrants. The Series A warrants and placement agent warrants were valued at $ 3.8 million and $ 0.2 million, respectively, using the Black-Scholes option pricing model based on the following assumptions: expected volatility 79.28 %, risk-free interest rate 3.06 %, expected dividend yield 0 %, and an expected term of 5.5 years. The Series B warrants were valued at $ 2.3 million using the Black-Scholes option pricing model based on the following assumptions: expected volatility 74.25 %, risk-free interest rate 3.16 %, expected dividend yield 0 %, and an expected term of 1.5 years. The amended warrants were valued at $ 1.0 million using the Black-Scholes option pricing model based on the following assumptions: expected volatility 79.28 %, risk-free interest rate 3.06 %, expected dividend yield 0 %, and an expected term of 5.5 years. The estimated fair value of the original warrants immediately prior to the warrant amendments was $ 0.5 million using Black-Scholes option pricing model based on the following assumptions: expected volatility ranging from 81.21 – 83.34 %, risk-free interest rates of 3.06 – 3.16 %, expected dividend yield 0 %, and an expected terms of 3.84 – 4.94 years. The warrant modifications resulted in an estimated value of $ 0.5 million, measured as the incremental fair value of the amended warrants, and was adjusted against the gross proceeds from the offering. As of September 30, 2023 , no warrants associated with the July 2022 Purchase Agreement have been exercised. As of September 30, 2023 , the Company had 3,996,418 shares and 124,202 shares of common stock reserved for issuance pursuant to the warrants and placement agent’s warrants, respectively, issued by the Company in the July 2022 Purchase Agreement, at an exercise price of $ 2.568 per share and $ 3.5225 per share, respectively. Common Stock Warrants As of September 30, 2023 , warrants to purchase 68 shares of common stock with an exercise price of $ 1,486.00 per share that were issued by Conatus in connection with obtaining financing in 2016 expired unexercised on July 3, 2023 . See warrant discussion above in connection with the January 2021 Offering, the June 2021 Offering, the December 2021 Offering, and the July 2022 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 41,861 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 16,336 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 were made under the 2017 Plan and any cancelled, forfeited or expired options were no t made available for granting. As of September 30, 2023 , 4,662 fully vested options remain outstanding 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) 42,500 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. On June 20, 2023, the Company held its 2023 Annual Meeting of Stockholders (the “Annual Meeting”) at which time the stockholders approved an amendment to the Company’s 2020 Plan to increase the number of shares authorized for issuance thereunder by 500,000 shares, as previously approved by the Board. The following summarizes activity related to the Company’s stock options under the 2017 Plan and the 2020 Plan for the nine months ended September 30, 2023: Options Weighted- Weighted- Aggregate Outstanding at December 31, 2022 113,279 $ 21.30 8.09 $ — Granted 472,454 0.94 Cancelled / Forfeited ( 371,301 ) 5.27 Outstanding at September 30, 2023 214,432 $ 4.20 9.29 $ — Vested and exercisable at September 30, 2023 22,912 $ 30.56 7.16 $ — Valuation of Stock Option Awards The following weighted-average assumptions were used to calculate the fair value of awards granted to employees, non-employees and directors: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected volatility — % — % 93.53 % 78.95 % Risk-free interest rate — % — % 3.91 % 2.14 % Expected option life (in years) — — 6.03 6.02 Expected dividend yield — % — % — % — % Additionally, in connection with the closing of the Merger, no further awards will be made under the Conatus 2013 Plan. As of September 30, 2023 , 4,487 fully vested options remain outstanding under the Conatus 2013 Plan with a weighted average exercise price of $ 740.10 per share. Restricted Stock Units On November 8, 2021, the Company granted 23,423 restricted stock units to the Company’s then Interim Chief Executive Officer, Chief Financial Officer, and Senior Vice President of Technical Operations. The fair value of the RSUs was $ 14.58 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, subject to continued service to the Company. Prior to RSU vesting, on November 7, 2022, the Company and the RSU recipients mutually agreed to enter into RSU Cancellation Agreements such that the RSU awards are cancelled and no longer outstanding. Forfeiture Stock Option Grants On March 10, 2023, the Company approved stock option grants to purchase 111,063 shares of the Company’s common stock to certain officers and employees as part of an annual award grant. Because the Company did not have sufficient shares available under the 2020 Plan at the time of approval, these shares were subject to forfeiture in the event that the shares available pursuant to the plan were not increased prior to the one-year anniversary and vesting of the award by an amount required to be available for issuance for all outstanding stock awards containing the forfeiture condition (“Forfeiture Stock Option Grants”). The Company had a conditional obligation to increase the shares available for issuance under the stock option plans before these Forfeiture Stock Option Grants can be granted at which time the Company would begin to recognize compensation costs from the inception date of the award through grant date. On June 20, 2023, the Company held its Annual Meeting at which the stockholders approved an amendment to the Company’s 2020 Plan to increase the number of shares authorized for issuance thereunder by 500,000 shares, which met the Company’s conditional obligation to increase the shares available for issuance. The Forfeiture Stock Options Grants were granted as of June 20, 2023. As such, during the three and nine months ended September 30, 2023, the Company began recognizing compensation expense for the Forfeiture Stock Option Grants dating back to the March 10, 2023 inception date of the grant awards. On September 18, 2023, the Company announced the Board approved a Plan of Dissolution and implemented a reduction in its workforce effective September 30, 2023. The reduction in workforce resulted in the forfeiture of 281,934 stock options granted under the 2020 Plan to certain officers and employees which did not meet certain vesting criteria. Stock Option Cancellations On March 10, 2023, the Company entered into Stock Option Cancellation Agreements with certain officers and employees (the “Option holders”), pursuant to which such individuals surrendered and cancelled 69,045 stock options with a weighted average price of $ 17.92 per share to purchase shares of the Company’s common stock (the “Cancelled Stock Options”). Pursuant to the terms of the Stock Option Cancellation Agreements, the Company agreed to pay each of the option holders a lump sum cash payment of $ 250 in exchange for the agreement to cancel the aforementioned stock options. The Company determined that because the Cancelled Stock Options were cancelled in exchange of cash consideration, the cash payments are considered partial settlements of the original awards and the cancellation should be accounted for as a repurchase of outstanding equity. The Company also determined that cash paid in exchange of cancellation was less than the fair value of the original awards and the stock options were probable of vesting pursuant to their original terms. Therefore, the Company recorded previously unrecognized compensation costs related to the Cancelled Stock Options of approximately $ 0 and $ 0.4 million dur ing the three and nine months ended September 30, 2023, respectively, on the accompanying condensed consolidated statements of operations. Inducement Grant On February 23, 2023, the Company issued 106,793 stock options to its newly appointed Executive Vice President and Chief Scientific Officer as an inducement grant outside of the Company’s equity incentive plans in accordance with Nasdaq Listing Rule 5635(c)(4). In accordance with the award agreement, 25 % of the options vest on the first anniversary of the employee’s hire date, on February 1, 2024, and then ratably over the remaining 36 months. Based on the terms being similar to standard grants as awarded under the 2020 Plan, the Company applied ASC 718 accounting basis for the recognition of share-based compensation expense. The inducement grant was valued at $ 0.1 million using the Black-Scholes option pricing model based on the following assumptions: expected volatility 91.65 %, risk-free interest rate 4.06 %, expected dividend yield 0 %, and an expected term of 6.08 years. On September 18, 2023, the Company announced the Board approved a Plan of Dissolution and implemented a reduction in its workforce effective September 30, 2023. The reduction in workforce also resulted in the forfeiture of 106,793 inducement grant stock options which did not meet certain vesting criteria. As of September 30, 2023, no inducement grant options were vested and no ne are outstanding. Stock-based Compensation Expense The compensation cost, including the inducement grant expense, that has been included in the accompanying condensed consolidated statements of operations for all stock-based compensation arrangements is detailed as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 General and administrative $ 6 $ 121 $ 415 $ 388 Research and development ( 13 ) 12 29 25 Total $ ( 7 ) $ 133 $ 444 $ 413 As of September 30, 2023 , total unrecognized compensation cost related to unvested options was approximately $ 0.1 million which is expected to be recognized over a weighted-average period of 2.87 years. Common Stock Reserved for Future Issuance Common stock reserved for future issuance is as follows: As of September 30, 2023 2022 Common stock warrants 4,876,571 4,876,639 Common stock options issued and outstanding under stock plans 218,919 129,006 Common stock available for issuance under stock plans 708,768 94,524 Total 5,804,258 5,100,169 |
Commitments and Contingencies
Commitments and Contingencies | 9 Months Ended |
Sep. 30, 2023 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | 8. Commitments and Contingencies Leases In January 2020, the Company entered into a long-term operating lease with San Diego Sycamore, LLC (“Sycamore”) for its headquarters that includes office and laboratory space. The lease commenced on March 1, 2020 and was set to expire on August 31, 2031 , with no options to renew or extend. The lease was accounted for as a modification of the Company’s existing lease with Sycamore as the lease agreement did not grant the Company an additional right-of-use asset. The terms of the lease agreement include seven 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 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 $ 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. During the year ended December 31, 2022, the Company completed construction of the building improvements. Due to construction delays, the tenant improvement construction period was extended by two months for which the Company was granted an incremental two-month extension of rent abatement and effectively shortened the lease term. Upon completion of the improvements, the building improvement costs in excess of the tenant improvement allowance that was funded by the Company were capitalized to the right-of-use-asset, to be amortized over the remaining lease term. As a result of the modification, the lease liability was remeasured and a corresponding increase of $ 0.4 million was recorded to both the lease liability and right-of-use-asset. On August 7, 2023, the Company entered into a Lease Termination Agreement (the “Lease Termination Agreement”) for its headquarters and laboratory operating lease, pursuant to which the Company and the landlord mutually agreed to accelerate the termination date to August 31, 2023 , subject to a termination fee paid by the Company of approximately $ 1.0 million. The Company entered into the Lease Termination Agreement primarily for the purpose of reducing the overall cash commitment and long-term liabilities related to the lease as part of the Company’s efforts to pursue potential strategic alternatives at the time. The lease termination eliminated the Company’s right-of-use assets and operating lease liabilities balance in its entirety and resulted in a credit of approximately $ 29 thousand, which was recognized as an adjustment against general and administrative expenses on the accompanying condensed consolidated statement of operations for the period ending September 30, 2023. The Company recognized a loss of $ 1.0 million resulting primarily from the lease termination fee, partially offset by the credit adjustment to eliminate the Company's right-of-use assets and operating lease liabilities. The lease termination will also result in the cancellation of the letter of credit during the fourth quarter of 2023, which will reclass $ 0.3 million of restricted cash to cash and cash equivalents on the accompanying condensed consolidated balance sheets. The Lease Termination Agreement was accounted for as a lease termination rather than a modification because the Company contemporaneously terminated the lease and its right-of-use of the facility. The tables below show the beginning balances of the operating right-of-use (“ROU”) assets and operating lease liabilities as of January 1, 2023 and the ending balances as of September 30, 2023, including the changes during the period (in thousands): Operating Operating lease ROU assets at January 1, 2023 $ 4,658 Amortization of operating lease ROU assets ( 223 ) Write off of ROU asset due to lease termination ( 4,435 ) Operating lease ROU assets at September 30, 2023 $ — Operating Operating lease liabilities at January 1, 2023 $ 4,617 Principal payments on operating lease liabilities ( 154 ) Write off of lease liability due to lease termination ( 4,463 ) Operating lease liabilities at September 30, 2023 $ — The Company leased certain office equipment that was classified as a finance lease. In parallel with terminating its operating lease, the Company early terminated its finance lease with payment of a termination fee of $ 14 thousand. As of September 30, 2023, the Company’s operating lease and finance lease were terminated and no future minimum payments of current or long-term lease liabilities remain on the accompanying condensed consolidated balance sheets. Employment and Severance Agreements On September 18, 2023, the Company announced that its Board had unanimously approved the dissolution and liquidation of Histogen pursuant to the Plan of Dissolution, subject to stockholder approval. In connection with the Plan of Dissolution, the Company discontinued all development programs and terminated all but two employees as of September 30, 2023. The focus of the remaining two employees is to manage the wind-down of the Company's operations and matters related to managing the Dissolution, including obtaining the necessary stockholder approval of the Plan of Dissolution. In connection with the employee terminations, the Company renegotiated severance obligations and entered into separation agreements that provide for severance payments in lieu of those set forth in the existing executive employment agreements. The Company also entered into amended and restated employment agreements with the two remaining employees tasked with managing the wind-down of operations, including a severance payment and provision for a retention payment for agreeing to oversee matters related to the Dissolution. As of September 30, 2023, the Company recorded severance payments obligations that represent a liability of $ 0.7 million on the accompanying condensed consolidated balance sheets. The Company has also agreed to $ 0.6 million of severance and retention payments that will be recognized ratably over the course of the Dissolution beginning October 1, 2023 which remains subject to recoupment by the Company in the event of a voluntary or for cause termination prior to final adjournment of the stockholders meeting. Material Contracts Pfizer Inc. In July 2010, Conatus entered into a Stock Purchase Agreement with Pfizer, pursuant to which it acquired all of the outstanding capital stock of Idun Pharmaceuticals, Inc., which was subsequently spun off to Conatus stockholders in January 2013. Under the stock purchase agreement, the Company may be required to make payments to Pfizer totaling $ 18.0 million upon the achievement of specified regulatory milestones. Prior to the termination of the Collaboration Agreement with Amerimmune on November 28, 2022, the obligations pursuant to the Stock Purchase Agreement were the responsibility of the Company's former collaboration partner, Amerimmune. In accordance with authoritative guidance, amounts for the milestone 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 payments have been recorded during the three and nine months ended September 30, 2023 and year ended December 31, 2022. 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 8,366 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 the Company 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 and nine months ended September 30, 2023 and year ended December 31, 2022. JHU License Agreement On April 3, 2023, the Company entered into an Exclusive License Agreement (the “JHU License Agreement”) with Johns Hopkins University (“Johns Hopkins”), pursuant to which Johns Hopkins granted the Company an exclusive license to certain intellectual property associated with the use of emricasan for the treatment of disease in humans resulting from viral or bacterial infections (including but not limited to, MRSA, VRSA, and SARS-CoV-2). In exchange, the Company agreed to pay Johns Hopkins an upfront license fee, reimbursement of certain patent costs, payments upon meeting certain milestones of up to $ 2.1 million, and royalty payments, including minimum annual royalty payments that totals $ 0.3 million of future payables creditable to the then current year royalties on net sales through 2033. The Company recognized expenses of $ 6 thousand and $ 112 thousand for the three and nine months ended September 30, 2023, respectively, related to the upfront license fee and reimbursement of intellectual property prosecution costs. The JHU License Agreement contains customary provisions on, among other things, termination, indemnification and patent prosecution and maintenance of the licensed intellectual property portfolio. 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 milestones that require milestone payments have been met and therefore no amounts for the milestone and royalty payments have been recorded during the three and nine months ended September 30, 2023. 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 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 September 30, 2023, no accruals have been made and no liability recognized related to such claims and legal proceedings. 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, the Company’s former Chief Executive Officer, as well as three individuals, two of which are currently employed by the Company. Although the complaint lists the “Histogen Board, 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 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 petitioned 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 hearing for the motion to compel arbitration was held on August 12, 2022 and the San Diego Superior Court issued a ruling to uphold the binding arbitration agreements signed by both plaintiffs. On July 10, 2023, plaintiff’s counsel filed a formal demand for arbitration for one of the plaintiffs. On August 3, 2023, a joint stipulation was filed dismissing the former Chief Executive Officer, as well as the three individuals, two of which are currently employed by the Company. The plaintiffs requested and the Company agreed to an additional pre-arbitration mediation, which was conducted on September 25, 2023. The Company and one of the plaintiffs reached a settlement agreement covered by the Company’s liability insurance, however, the matter remains unresolved between the Company and the second plaintiff. The matter is expected to proceed to arbitration but is the responsibility of the remaining plaintiff to follow through with the initiation of the arbitration proceeding. The Company believes that defense costs, settlement monies, damages or any other awards would be covered by their liability insurance; provided, however, insurance may not cover all claims or could exceed their insurance coverage. The Company believes that there are substantial defenses to this lawsuit, and intends to vigorously defend against each of these claims. While this litigation matter is in the early stages for the remaining plaintiff, the Company believes the action is without merit. Nonetheless, the ultimate outcome is unknown at this time. |
Related Parties
Related Parties | 9 Months Ended |
Sep. 30, 2023 | |
Related Party Transactions [Abstract] | |
Related Parties | 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 both September 30, 2023 and December 31, 2022, Lordship controlled approximately 2.8 % of the Company’s outstanding voting shares, respectively, and currently holds two Board 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 generated from their Human Multipotent Cell Conditioned Media, or CCM, and their Human Extracellular Matrix, or hECM, in connection with the Company’s biologics technology platform. 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. The Company recogni zed $ 0 expense to Lordship for both the three months ended September 30, 2023 and 2022, and $ 0 a nd $ 375 thousand for the nine months ended September 30, 2023 and 2022, respectively, all of which is included in general and administrative expenses on the accompanying condensed consolidated statements of operations. As of September 30, 2023 and December 31, 2022 , there was a balance of $ 9 thousand and $ 10 thousand, respectively, paid to Lordship included as a component of other assets on the accompanying consolidated balance sheets in connection with the deferral of revenue from the Allergan license transfer agreements. Refer to Note 10 for further information. |
Subsequent Events
Subsequent Events | 9 Months Ended |
Sep. 30, 2023 | |
Subsequent Events [Abstract] | |
Subsequent Events | 10. Subsequent Events On October 3, 2023, the Company entered into an Asset Purchase Agreement with Allergan Sales, LLC (“Allergan”), pursuant to which Histogen and its affiliates sold to Allergan certain assets, including certain patents and other intellectual property rights, related to Histogen’s hypoxia generated growth factor technology. In exchange, Allergan agreed to pay Histogen a purchase price of $ 2.1 million and agreed to assume certain liabilities as set forth in the Asset Purchase Agreement. The Asset Purchase Agreement contains customary provisions on, among other things, representation and warranties, and covenants related to the transfer of ownership of the acquired assets and other matters. In connection with the Transaction, on October 3, 2023, the Company and Allergan mutually elected to terminate the Allergan License Agreements, as amended from time to time. In connection with the Transaction, on October 3, 2023, the Company also entered into a Mutual Termination of the Second Amended and Restated Strategic Relationship Success Fee Agreement (the “Lordship Agreement’) with Lordship, pursuant to which Histogen agreed to pay Lordship a mutually agreed to success and termination fee of $ 0.4 million as required by the terms of the Lordship Agreement. |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 9 Months Ended |
Sep. 30, 2023 | |
Accounting Policies [Abstract] | |
Description of Business | 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. Until recently, the Company was a clinical-stage therapeutics company focused on developing potential first-in-class clinical and preclinical small molecule pan-caspase and caspase selective inhibitors that protect the body’s natural process to restore immune function. 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 (“Nasdaq”) under the ticker symbol “HSTO”. On September 18, 2023, the Company announced, after extensive consideration of potential strategic alternatives, that its Board of Directors (the “Board”), had unanimously approved the dissolution and liquidation of Histogen (the “Dissolution”) pursuant to a plan of complete liquidation and dissolution (the “Plan of Dissolution”), subject to stockholder approval. In connection with the Plan of Dissolution, the Company discontinued all development programs and terminated all but two employees as of September 30, 2023. The focus of the remaining two employees is to manage the wind-down of the Company's operations and matters related to managing the Dissolution, including obtaining the necessary stockholder approval of the Plan of Dissolution. Additionally, the Company is currently seeking to sell their caspase program assets and other remaining assets. In light of the planned dissolution, on September 26, 2023, the Company received written notice from Nasdaq advising the Company that based upon Nasdaq’s review and pursuant to Listing Rule 5101, Nasdaq believed that the Company is a “public shell,” and that the continued listing of our securities was no longer warranted. As a result, the trading of the Company's common stock was suspended as of the opening of business on October 5, 2023, and on October 12, 2023, Nasdaq filed a Form 25-NSE with the Securities and Exchange Commission (“SEC”), which removed the Company's common stock from listing and registration on Nasdaq. |
Recent Developments | Recent Developments On October 3, 2023, the Company entered into an Asset Purchase Agreement (the “Asset Purchase Agreement”) with Allergan Sales, LLC (“Allergan”), pursuant to which Histogen and its affiliates sold to Allergan certain assets, including certain patents and other intellectual property rights, related to Histogen’s hypoxia generated growth factor technology (the “Transaction”). In exchange, Allergan agreed to pay Histogen a purchase price of $ 2.1 million and agreed to assume certain liabilities as set forth in the Asset Purchase Agreement. The Asset Purchase Agreement contains customary provisions on, among other things, representation and warranties, and covenants related to the transfer of ownership of the acquired assets and other matters. In connection with the Transaction, on October 3, 2023, the Company and Allergan mutually elected to terminate the Allergan License Agreements, as amended from time to time. In connection with the Transaction, on October 3, 2023, the Company also entered into a Mutual Termination of the Second Amended and Restated Strategic Relationship Success Fee Agreement (the “Lordship Agreement’) with Lordship Ventures LLC (“Lordship”), pursuant to which Histogen agreed to pay Lordship a mutually agreed to success and termination fee as required by the terms of the Lordship Agreement (refer to Note 10 for further information). |
Reverse Stock Split | Reverse Stock Split On June 2, 2022, the Company’s Board approved a one-for- twenty reverse stock split of its then outstanding common stock (the “Reverse Stock Split”) with any fractional shares resulting from the Reserve Stock Split rounded down to the next whole share of common stock. The par value and the authorized shares of the common stock were not adjusted as a result of the Reverse Stock Split. All references to share and per share amounts for all periods presented in the condensed consolidated financial statements have been retrospectively restated to reflect this Reverse Stock Split. Additionally, all rights to receive shares of common stock under outstanding warrants, options, and restricted stock units (“RSUs”) were adjusted to give effect of the reverse stock split. Furthermore, remaining shares of common stock available for future issuance under stock-based payment award plans and employee stock purchase plans were adjusted to give effect to the Reverse Stock Split. |
Liquidity and Going Concern | Liquidity and Going Concern The Company has incurred operating losses and negative cash flows from operations and had an accumulated deficit of $ 97.7 million as of September 30, 2023. The Company expects operating losses and negative cash flows from operations to continue for the foreseeable future, including through the execution of the Plan of Dissolution if approved by the Company’s stockholders. In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about its ability to continue as a going concern within one year after the date that these consolidated financial statements are issued on November 9, 2023. The Company has determined that its cash and cash equivalents as of September 30, 2023 of $ 4.6 million would be insufficient to fund its operations for a period of at least twelve months from the date of these financial statements which raises substantial doubt regarding the Company’s ability to continue as a going concern. The Company does not have plans to alleviate the substantial doubt about the Company’s ability to continue as a going concern. On September 18, 2023, the Company announced that the Board unanimously approved the Plan of Dissolution. As the Plan of Dissolution has not yet been brought to a vote or approved by the Company’s stockholders, the Company concluded that the liquidation basis of accounting should not be applied as of the balance sheet date. Accordingly, the accompanying financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The condensed consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from the outcome of these uncertainties described above. |
Basis of Presentation and Principles of Consolidation | 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 accounting principles generally accepted in the United States (“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 was a wholly-owned subsidiary intended to pursue registration with the COFEPRIS (Mexico equivalent to Food and Drug Administration). Since the Company acquired CIMRESA in 2018, there have been no financial or operational activities. On January 17, 2023, the Company sold the wholly-owned subsidiary, CIMRESA, and deconsolidated the former subsidiary, resulting in a gain during the nine months ended September 30, 2023. 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 (refer to Note 2 for further information). |
Unaudited Interim Financial Information | Unaudited Interim Financial Information The unaudited condensed consolidated financial statements for the three and nine months ended September 30, 2023 and 2022 have been prepared in accordance with the rules and regulations of the 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, 2022 included in the Annual Report on Form 10-K that the Company filed with the SEC on March 9, 2023. |
Use of Estimates | 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 to the business and operating results presents additional uncertainty, the Company continues to use the best information available to them in their significant accounting estimates. Significant estimates and assumptions include those related to the useful lives of property and equipment, discount rates used in recognizing contracts containing leases, unrecognized tax benefits, and volatility used for stock-based compensation option pricing. Actual results may materially differ from those estimates. |
Variable Interest Entities | 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 | 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 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 | 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 | 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. Customer Risk During the three and nine months ended September 30, 2023 and 2022 , one customer accounted for 100 % of total revenues. |
Accounts Receivable | Accounts Receivable Accounts receivable are generally due within 30 days and are recorded net of the allowance for doubtful accounts, if any. Management considers all accounts receivable to be recoverable, and accordingly, no provision for doubtful accounts was recorded at December 31, 2022. No accounts receivable are recorded as of September 30, 2023 on the accompanying condensed consolidated balance sheets. |
Property and Equipment | 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. No property and equipment are recorded as of September 30, 2023 on the accompanying condensed consolidated balance sheets. |
Valuation of Long-Lived Assets | 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. During the three months ended September 30, 2023, the Company disposed of its remaining property and equipment and, as of September 30, 2023 , other assets are the remaining long-lived assets recorded on the accompanying condensed consolidated balance sheets (refer to Note 4 for further information). |
Comprehensive Loss | Comprehensive Loss The Company is required to report all components of comprehensive loss, including net loss, in the accompanying condensed consolidated financial statements in the period in which they are recognized. Comprehensive loss is defined as 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 | Revenue Recognition 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. The Company applies the revenue recognition standard, including the use of any practical expedients, consistently to contracts with similar characteristics and in similar circumstances (refer to Note 5 for further information). Grant Awards 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 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 and nine months ended September 30, 2023, qualifying expenses totaling $ 0 and $ 0.1 million have been incurred with a corresponding reduction of research and development expenses related to the award, respectively. As of September 30, 2023 and December 31, 2022, $ 0 and $ 0.1 million was included in accounts receivable within the condensed consolidated balance sheets with respect to the award, respectively. The Company made the decision in December 2022 to terminate the study for futility regarding patient recruitment and redirect efforts and funding away from HST-003 to other product candidates. As of March 31, 2023, the Company had completed its HST-003 clinical study close-out activities and early terminated the grant award. |
Research and Development Expenses | 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, net of reimbursable research and development costs incurred under the DoD grant. |
General and Administrative Expenses | 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 consist of professional fees for legal (including patent costs), audit and other consulting services, travel and entertainment, recruiting, facility costs, general information technology costs, depreciation and amortization, and other general corporate overhead expenses. |
Patent Costs | 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 as a component of general and administrative expenses in the accompanying consolidated statements of operations. |
Income Taxes | Income Taxes Income taxes are accounted for under the asset and liability method. Deferred income taxes are recorded for temporary differences between 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 and nine months ended September 30, 2023 and 2022, 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 | 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. For the three and nine months ended September 30, 2023 and 2022, diluted net loss per share attributable to common stockholders is equal to 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): September 30, 2023 September 30, 2022 Common stock options issued and outstanding 218,919 129,006 Warrants to purchase common stock 4,876,571 4,876,639 Total anti-dilutive shares 5,095,490 5,005,645 |
Stock-Based Compensation | 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. |
Recently Issued Accounting Pronouncements Not Yet Adopted | Recently Issued Accounting Pronouncements Not Yet Adopted In March 2023, the FASB issued ASU No. 2023-01, Leases (Topic 842): Common Control Arrangements (“ASU 2023-01” ), amending certain provisions of ASC 842 that apply to arrangements between related parties under common control. This standard amends the accounting for leasehold improvements in common-control arrangements for all entities. The amendments in this ASU are effective for public business entities for fiscal years beginning after December 15, 2023, including interim periods within those fiscal years, with early adoption permitted. The Company does not expect to early adopt this guidance and is in the process of evaluating the impact of adoption of this guidance on the Company’s consolidated financial statements. |
Recently Adopted Accounting Pronouncements | Recently Adopted Accounting Pronouncements None. |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Accounting Policies [Abstract] | |
Summary of Outstanding Potentially Dilutive Shares Excluded in Calculation of Diluted Net Loss Per Share | 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): September 30, 2023 September 30, 2022 Common stock options issued and outstanding 218,919 129,006 Warrants to purchase common stock 4,876,571 4,876,639 Total anti-dilutive shares 5,095,490 5,005,645 |
Property and Equipment, Net (Ta
Property and Equipment, Net (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Property, Plant and Equipment [Abstract] | |
Schedule of Property and Equipment, Net | Property and equipment, net consisted of the following (in thousands): September 30, December 31, Lab and manufacturing equipment $ — $ 937 Office furniture and equipment — 225 Software — 48 Total — 1,210 Less: accumulated depreciation and amortization — ( 774 ) Property and equipment, net $ — $ 436 |
Balance Sheet Details (Tables)
Balance Sheet Details (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Balance Sheet Related Disclosures [Abstract] | |
Summary of Prepaid and Other Current Assets | Prepaid and other current assets consisted of the following (in thousands): September 30, December 31, Insurance $ 463 $ 626 Prepaid rent — 81 Pre-clinical and clinical related expenses — 64 Prepaid corporate taxes 79 — Other 40 77 Total $ 582 $ 848 |
Summary of Other Assets | Other assets consisted of the following (in thousands): September 30, December 31, Insurance $ 353 $ 513 Other 9 10 Total $ 362 $ 523 |
Summary of Accrued Liabilities | Accrued liabilities consisted of the following (in thousands): September 30, December 31, Current portion of finance lease liabilities $ — $ 9 Accrued compensation 787 160 Preclinical and clinical related expenses — 150 Legal fees 134 44 Accrued franchise tax — 162 Other 22 70 Total $ 943 $ 595 |
Stockholders' Equity (Tables)
Stockholders' Equity (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Equity [Abstract] | |
Summary of Stock Option Activity | The following summarizes activity related to the Company’s stock options under the 2017 Plan and the 2020 Plan for the nine months ended September 30, 2023: Options Weighted- Weighted- Aggregate Outstanding at December 31, 2022 113,279 $ 21.30 8.09 $ — Granted 472,454 0.94 Cancelled / Forfeited ( 371,301 ) 5.27 Outstanding at September 30, 2023 214,432 $ 4.20 9.29 $ — Vested and exercisable at September 30, 2023 22,912 $ 30.56 7.16 $ — |
Summary of Valuation of Stock Option Awards | The following weighted-average assumptions were used to calculate the fair value of awards granted to employees, non-employees and directors: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected volatility — % — % 93.53 % 78.95 % Risk-free interest rate — % — % 3.91 % 2.14 % Expected option life (in years) — — 6.03 6.02 Expected dividend yield — % — % — % — % Additionally, in connection with the closing of the Merger, no further awards will be made under the Conatus 2013 Plan. As of September 30, 2023 , 4,487 fully vested options remain outstanding under the Conatus 2013 Plan with a weighted average exercise price of $ 740.10 per share. |
Summary of Compensation Cost Including Inducement Grant Expense Included in Condensed Consolidated Statements of Operations for Stock-based Compensation Arrangements | The compensation cost, including the inducement grant expense, that has been included in the accompanying condensed consolidated statements of operations for all stock-based compensation arrangements is detailed as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 General and administrative $ 6 $ 121 $ 415 $ 388 Research and development ( 13 ) 12 29 25 Total $ ( 7 ) $ 133 $ 444 $ 413 |
Summary of Common Stock Reserved for Future Issuance | Common stock reserved for future issuance is as follows: As of September 30, 2023 2022 Common stock warrants 4,876,571 4,876,639 Common stock options issued and outstanding under stock plans 218,919 129,006 Common stock available for issuance under stock plans 708,768 94,524 Total 5,804,258 5,100,169 |
Commitments and Contingencies (
Commitments and Contingencies (Tables) | 9 Months Ended |
Sep. 30, 2023 | |
Commitments and Contingencies Disclosure [Abstract] | |
Summary of Changes in ROU Assets and Lease Liabilities | The tables below show the beginning balances of the operating right-of-use (“ROU”) assets and operating lease liabilities as of January 1, 2023 and the ending balances as of September 30, 2023, including the changes during the period (in thousands): Operating Operating lease ROU assets at January 1, 2023 $ 4,658 Amortization of operating lease ROU assets ( 223 ) Write off of ROU asset due to lease termination ( 4,435 ) Operating lease ROU assets at September 30, 2023 $ — Operating Operating lease liabilities at January 1, 2023 $ 4,617 Principal payments on operating lease liabilities ( 154 ) Write off of lease liability due to lease termination ( 4,463 ) Operating lease liabilities at September 30, 2023 $ — |
Description of Business and B_2
Description of Business and Basis of Presentation - Additional Information (Detail) $ in Thousands | 9 Months Ended | |||||
Aug. 07, 2023 USD ($) | Jun. 02, 2022 | Sep. 30, 2023 USD ($) | Oct. 03, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2022 USD ($) | |
Description of Business and Basis of Presentation [Line Items] | ||||||
Lease termination date | Aug. 31, 2031 | |||||
Restricted cash | $ 300 | $ 400 | ||||
Reverse stock split description | one-for-twenty | |||||
Reverse stock split conversion ratio | 0.20 | |||||
Accumulated deficit | $ (97,686) | $ (88,273) | ||||
Cash and cash equivalents | $ 4,573 | $ 12,109 | $ 14,552 | |||
Lease Termination Agreement [Member] | ||||||
Description of Business and Basis of Presentation [Line Items] | ||||||
Lease termination date | Aug. 31, 2023 | |||||
Lease termination fees | $ 1,000 | |||||
Subsequent Event [Member] | ||||||
Description of Business and Basis of Presentation [Line Items] | ||||||
Payment receivable from sale of assets | $ 2,100 |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 9 Months Ended | |||
Sep. 30, 2020 USD ($) | Sep. 30, 2023 USD ($) shares | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) Segment shares | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) shares | |
Summary Of Significant Accounting Policies [Line Items] | ||||||
Percentage ownership not considered variable interest entity | 100% | |||||
Number of operating segment | Segment | 1 | |||||
Accounts receivable | $ (99,000) | $ (91,000) | ||||
Accounts receivable | $ 0 | 0 | $ 99,000 | |||
Property and equipment, net | $ 0 | $ 0 | $ 436,000 | |||
Shares issued | shares | 0 | 0 | 0 | |||
Income tax expense benefit | $ 0 | $ 0 | $ 0 | $ 0 | ||
U.S. Department of Defense ("DoD") [Member] | ||||||
Summary Of Significant Accounting Policies [Line Items] | ||||||
Accounts receivable from customer | 0 | 0 | $ 100,000 | |||
Grant funding obtained | $ 2,000,000 | |||||
Grant award expiration period | 2025-09 | |||||
Qualifying expenses incurred | $ 0 | $ 100,000 | ||||
Furniture and All Equipment [Member] | Maximum [Member] | ||||||
Summary Of Significant Accounting Policies [Line Items] | ||||||
Estimated useful lives of the assets | 5 years | 5 years | ||||
Software [Member] | Maximum [Member] | ||||||
Summary Of Significant Accounting Policies [Line Items] | ||||||
Estimated useful lives of the assets | 3 years | 3 years | ||||
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | One Customer [Member] | ||||||
Summary Of Significant Accounting Policies [Line Items] | ||||||
Percentage of revenues | 100% | 100% | 100% | 100% | ||
Settlement Agreement [Member] | ||||||
Summary Of Significant Accounting Policies [Line Items] | ||||||
Variable interest entity, ownership percentage | 50% |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Summary of Outstanding Potentially Dilutive Shares Excluded in Calculation of Diluted Net Loss Per Share (Detail) - shares | 6 Months Ended | 9 Months Ended |
Jun. 30, 2023 | Sep. 30, 2023 | |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Outstanding potentially dilutive securities | 5,005,645 | 5,095,490 |
Common stock options issued and outstanding [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Outstanding potentially dilutive securities | 129,006 | 218,919 |
Warrants to purchase common stock [Member] | Common Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Outstanding potentially dilutive securities | 4,876,639 | 4,876,571 |
Property and Equipment, Net - S
Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) | Sep. 30, 2023 | Dec. 31, 2022 |
Property Plant And Equipment [Line Items] | ||
Property and equipment, gross | $ 1,210,000 | |
Less: accumulated depreciation and amortization | (774,000) | |
Property and equipment, net | $ 0 | 436,000 |
Lab and Manufacturing Equipment [Member] | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, gross | 937,000 | |
Office Furniture and Equipment [Member] | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, gross | 225,000 | |
Software [Member] | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, gross | $ 48,000 |
Property and Equipment, Net - A
Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | |
Sep. 30, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | |
Property, Plant and Equipment [Abstract] | |||
Depreciation and amortization | $ 100 | $ 102 | |
Disposal of property and equipment | $ 1,200 | 1,200 | |
Accumulated depreciation | 900 | ||
Loss from disposal of property and equipment | $ (324) | $ (324) |
Balance Sheet Details - Summary
Balance Sheet Details - Summary of Prepaid and Other Current Assets (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 |
Balance Sheet Related Disclosures [Abstract] | ||
Insurance | $ 463 | $ 626 |
Prepaid rent | 81 | |
Pre-clinical and clinical related expenses | 64 | |
Prepaid corporate taxes | 79 | |
Other | 40 | 77 |
Total | $ 582 | $ 848 |
Balance Sheet Details - Summa_2
Balance Sheet Details - Summary of Other Assets (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 |
Balance Sheet Related Disclosures [Abstract] | ||
Insurance | $ 353 | $ 513 |
Other | 9 | 10 |
Total | $ 362 | $ 523 |
Balance Sheet Details - Summa_3
Balance Sheet Details - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 |
Balance Sheet Related Disclosures [Abstract] | ||
Current portion of finance lease liabilities | $ 9 | |
Accrued compensation | $ 787 | 160 |
Preclinical and clinical related expenses | 150 | |
Legal fees | 134 | 44 |
Accrued franchise tax | 162 | |
Other | 22 | 70 |
Total | $ 943 | $ 595 |
Revenues - Additional Informati
Revenues - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | |||||
Mar. 31, 2022 USD ($) | Jan. 31, 2020 USD ($) Kilograms | Mar. 31, 2019 USD ($) | Dec. 31, 2017 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) | |
Disaggregation of Revenue [Line Items] | |||||||||
Revenue | $ 5,000 | $ 5,000 | $ 15,000 | $ 3,765,000 | |||||
Deferred revenue | 100,000 | 100,000 | $ 100,000 | ||||||
2017 Allergan Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Cash payment received | $ 11,000,000 | ||||||||
Potential additional payments | 5,500,000 | ||||||||
2019 Allergan Amendment Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
One-time payment | $ 7,500,000 | ||||||||
2020 Allergan Amendment Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Revenue | 0 | 0 | 0 | 0 | |||||
Up front payment received | $ 1,000,000 | ||||||||
Additional quantity of product to be supplied | Kilograms | 200 | ||||||||
Revenue related to Potential Future Improvements | $ 200,000 | ||||||||
Revenue recognized | 5,000 | 15,000 | |||||||
2022 Allergan Letter Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Potential milestone payment | 5,500,000 | ||||||||
Potential milestone payment recognized | $ 3,800,000 | ||||||||
Product [Member] | 2017 Allergan Agreement [Member] | Minimum [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Sales target for additional potential payment payout | 60,000,000 | ||||||||
Product [Member] | 2022 Allergan Letter Agreement [Member] | Minimum [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Sales target for potential milestone payment | $ 60,000,000 | ||||||||
License [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Revenue | $ 5,000 | $ 5,000 | $ 15,000 | $ 3,765,000 | |||||
License [Member] | 2019 Allergan Amendment Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Revenue | $ 7,500,000 | ||||||||
License [Member] | 2022 Allergan Letter Agreement [Member] | |||||||||
Disaggregation of Revenue [Line Items] | |||||||||
Revenue | $ 3,800,000 |
Redeemable Convertible Prefer_2
Redeemable Convertible Preferred Stock - Additional Information (Details) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended | ||||
Apr. 14, 2022 Vote $ / shares | Jun. 29, 2022 USD ($) $ / shares shares | Mar. 31, 2022 USD ($) $ / shares shares | Sep. 30, 2022 shares | Sep. 30, 2023 $ / shares shares | Sep. 30, 2022 USD ($) shares | Dec. 31, 2022 $ / shares shares | |
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock, stated value per share | $ 0.0001 | $ 0.0001 | |||||
Proceeds from the issuance of common stock, net of issuance costs | $ | $ 4,414 | ||||||
Expected volatility | 93.53% | 78.95% | |||||
Risk-free interest rate | 3.91% | 2.14% | |||||
Expected term | 6 years 10 days | 6 years 7 days | |||||
Common stock reserved for issuance | shares | 5,100,169 | 5,804,258 | 5,100,169 | ||||
Redemption payment by the Company | $ | $ 488 | ||||||
Common stock, par value | $ 0.0001 | $ 0.0001 | |||||
March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Offering price per share | $ 25 | ||||||
Warrant purchase percentage | 7% | ||||||
Warrants to purchase common stock | shares | 17,501 | ||||||
Exercise price percentage | 125% | ||||||
Warrants exercisable expiration period | 5 years 6 months | ||||||
Warrant issuance date | Sep. 25, 2022 | ||||||
Common stock reserved for issuance | shares | 17,501 | ||||||
Exercise price of warrant per share | $ 25 | ||||||
March 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Aggregate value of warrants | $ | $ 34 | ||||||
March 2022 Offering [Member] | Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Expected volatility | 78.90% | ||||||
Risk-free interest rate | 2.40% | ||||||
Expected dividend yield | 0% | ||||||
Expected term | 5 years 6 months | ||||||
Preferred Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock, stated value per share | $ 1,000 | $ 1,000 | |||||
Proceeds from the issuance of common stock, net of issuance costs | $ | $ 5,250 | ||||||
Proceeds held in escrow | $ | $ 4,760 | ||||||
Preferred Stock, Redemption Terms | (i) the earlier of (1) the receipt of authorized stockholder approval for the reverse stock split and (2) the date that was 90 days following the Original Issue Date of March 25, 2022, and (ii) before the date that was 120 days after the Original Issue Date or July 23, 2022 (the “Redemption Period”) | ||||||
Preferred stock redemption percentage of stated value per share | 105% | 105% | |||||
Redemption payment by the Company | $ | $ 500 | ||||||
Accretion of Preferred Stock to its redemption value recorded as a reduction to additional paid-in capital. | $ | 1,100 | ||||||
Deemed dividend related to the accretion of the discount and redemption feature | $ | $ 500 | ||||||
Preferred Stock [Member] | March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock, stated value per share | $ 1,000 | ||||||
Percentage of original issue discount | 5% | ||||||
Proceeds from the issuance of common stock, net of issuance costs | $ | $ 4,760 | ||||||
Closing date | Mar. 25, 2022 | ||||||
Proceeds held in escrow | $ | $ 4,760 | ||||||
Fair value recognized | $ | 4,760 | ||||||
Placement agent's fees and other offering expenses | $ | $ 600 | ||||||
Common Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Issuance of common stock, net of issuance costs, shares | shares | 1,774,309 | ||||||
Exercise price of warrant per share | $ 1,486 | ||||||
Series A Redeemable Convertible Preferred Stock [Member] | Preferred Stock [Member] | March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Issuance of common stock, net of issuance costs, shares | shares | 2,500 | ||||||
Preferred stock, stated value per share | $ 0.0001 | ||||||
Offering price per share | $ 952.38 | ||||||
Series A Preferred Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock, stated value per share | $ 1,000 | 1,000 | |||||
Conversion price per share | $ 20 | ||||||
Number of votes per each share | Vote | 3,776 | ||||||
Preferred stock, NASDAQ minimum price | $ 0.2648 | ||||||
Preferred stock, voting rights description | Each share of Series A Preferred Stock outstanding on April 14, 2022 (the “Record Date”) had 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 had 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 of the Series A Preferred Stock agreed to not transfer their shares of Series A Preferred Stock until after the 2022 Annual Meeting and to vote all shares of Series A Preferred Stock in favor of the Reverse Stock Split Proposal. | ||||||
Series A Preferred Stock [Member] | Preferred Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock redeemed | shares | 2,500 | ||||||
Redeemable convertible preferred stock, shares outstanding | shares | 0 | 0 | |||||
Series A Preferred Stock [Member] | Preferred Stock [Member] | March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Issuance of common stock, net of issuance costs, shares | shares | 125,000 | ||||||
Preferred stock, stated value per share | $ 1,000 | ||||||
Conversion price per share | $ 20 | ||||||
Series A Preferred Stock [Member] | Common Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Percentage of aggregate votes cast on reverse stock split voted in favor thereof | 70% | ||||||
Percentage of aggregate votes cast on reverse stock split voted against | 30% | ||||||
Convertible preferred stock conversion in to common stock | shares | 125,000 | ||||||
Series B Redeemable Convertible Preferred Stock [Member] | Preferred Stock [Member] | March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Issuance of common stock, net of issuance costs, shares | shares | 2,500 | ||||||
Preferred stock, stated value per share | $ 0.0001 | ||||||
Offering price per share | $ 952.38 | ||||||
Series B Preferred Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock, stated value per share | $ 1,000 | ||||||
Conversion price per share | $ 20 | ||||||
Preferred stock, voting rights description | Each share of Series B Preferred Stock outstanding on the Record Date entitled the holder thereof to cast 30,000 votes on the Reverse Stock Split Proposal. The holders of the Series B Preferred Stock agreed to not transfer their shares of Series B Preferred Stock until after the 2022 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. | ||||||
Number of votes on reverse stock split | Vote | 30,000 | ||||||
Series B Preferred Stock [Member] | Preferred Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Preferred stock redeemed | shares | 2,500 | ||||||
Redeemable convertible preferred stock, shares outstanding | shares | 0 | 0 | |||||
Series B Preferred Stock [Member] | Preferred Stock [Member] | March 2022 Offering [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Issuance of common stock, net of issuance costs, shares | shares | 125,000 | ||||||
Preferred stock, stated value per share | $ 1,000 | ||||||
Conversion price per share | $ 20 | ||||||
Series B Preferred Stock [Member] | Common Stock [Member] | |||||||
Redeemable Convertible Preferred Stock [Line Items] | |||||||
Percentage of aggregate votes cast on reverse stock split voted in favor thereof | 70% | ||||||
Percentage of aggregate votes cast on reverse stock split voted against | 30% | ||||||
Convertible preferred stock conversion in to common stock | shares | 125,000 |
Stockholders' Equity - Addition
Stockholders' Equity - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended | |||||||||||||
Sep. 18, 2023 | Jun. 20, 2023 | Mar. 10, 2023 | Feb. 23, 2023 | Jul. 12, 2022 | Nov. 08, 2021 | Dec. 31, 2021 | Jun. 30, 2021 | Jan. 31, 2021 | May 31, 2020 | Apr. 30, 2019 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Nov. 30, 2020 | Dec. 18, 2017 | |
Class Of Stock [Line Items] | ||||||||||||||||
Proceeds from the issuance of common stock, net of issuance costs | $ 4,414,000 | |||||||||||||||
Expected volatility | 93.53% | 78.95% | ||||||||||||||
Risk-free interest rate | 3.91% | 2.14% | ||||||||||||||
Expected term | 6 years 10 days | 6 years 7 days | ||||||||||||||
Common stock reserved for issuance | 5,100,169 | 5,804,258 | 5,100,169 | |||||||||||||
Warrants to purchase common stock | 4,876,639 | 4,876,571 | 4,876,639 | |||||||||||||
Cancellation payment for employees | $ 250 | |||||||||||||||
Unrecognized compensation expense | $ 100,000 | |||||||||||||||
Weighted-average vesting term | 2 years 10 months 13 days | |||||||||||||||
2017 Plan [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Number of common stock shares authorized to issue | 41,861 | |||||||||||||||
Increase in number of common stock available for grant | 16,336 | |||||||||||||||
Vesting period | 4 years | |||||||||||||||
Expiration period | 10 years | |||||||||||||||
Stock options issued | 0 | |||||||||||||||
Number of fully vested options outstanding | 4,662 | |||||||||||||||
Number of shares subject to forfeiture | 0 | |||||||||||||||
2020 Stock Plan [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Number of common stock shares authorized to issue | 42,500 | |||||||||||||||
Expiration period | 10 years | |||||||||||||||
Percentage of outstanding shares of common stock | 5% | |||||||||||||||
Number of additional shares authorized for issuance | 500,000 | |||||||||||||||
Number of shares subject to forfeiture | 281,934 | |||||||||||||||
Conatus 2013 Plan [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Stock options issued | 0 | |||||||||||||||
Number of fully vested options | 4,487 | |||||||||||||||
Weighted average exercise price of fully vested options | $ 740.1 | |||||||||||||||
Inducement Grant options vested | 4,487 | |||||||||||||||
Stock Option Cancellations [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Number of shares subject to forfeiture | 69,045 | |||||||||||||||
Weighted-Average Exercise Price, Cancelled / Forfeited | $ 17.92 | |||||||||||||||
Unrecognized compensation expense | $ 400,000 | |||||||||||||||
Forfeiture Stock Option Grants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Number of Options, Granted | 111,063 | |||||||||||||||
Employee Stock Option | Inducement Grant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Vesting period | 36 months | |||||||||||||||
Vesting term | In accordance with the award agreement, 25% of the options vest on the first anniversary of the employee’s hire date, on February 1, 2024, and then ratably over the remaining 36 months. | |||||||||||||||
Employee Stock Option | Inducement Grant [Member] | Share-based Payment Arrangement, Tranche One [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Remaining vesting percentage | 25% | |||||||||||||||
Employee Stock Option | Inducement Grant [Member] | Executive Vice President and Chief Scientific Officer [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Stock options issued | 106,793 | |||||||||||||||
Restricted Stock Units [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Vesting term | 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, subject to continued service to the Company. Prior to RSU vesting, on November 7, 2022, the Company and the RSU recipients mutually agreed to enter into RSU Cancellation Agreements such that the RSU awards are cancelled and no longer outstanding. | |||||||||||||||
Number of restricted stock units granted | 23,423 | |||||||||||||||
Fair value per share | $ 14.58 | |||||||||||||||
Number of restricted stock units outstanding | 0 | |||||||||||||||
Black-Scholes Option Pricing Model [Member] | Employee Stock Option | Inducement Grant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Expected volatility | 91.65% | |||||||||||||||
Risk-free interest rate | 4.06% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 6 years 29 days | |||||||||||||||
Aggregate value of inducement grant | $ 100,000 | |||||||||||||||
Number of fully vested options | 0 | |||||||||||||||
Number of fully vested options outstanding | 0 | |||||||||||||||
Number of shares subject to forfeiture | 106,793 | |||||||||||||||
Inducement Grant options vested | 0 | |||||||||||||||
July 2022 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Combined purchase price of one share of common stock and accompanying warrant | $ 2.818 | |||||||||||||||
Proceeds from the issuance of common stock, net of issuance costs | $ 5,000,000 | |||||||||||||||
July 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Gross proceeds from offering of warrants | $ 500,000 | |||||||||||||||
July 2022 Offering [Member] | Pre-funded Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 1,774,309 | |||||||||||||||
Exercise price of warrant per share | $ 0.0001 | |||||||||||||||
July 2022 Offering [Member] | Series A Warrant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 1,774,309 | |||||||||||||||
Exercise price of warrant per share | $ 2.568 | |||||||||||||||
July 2022 Offering [Member] | Series B Warrant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 1,774,309 | |||||||||||||||
Exercise price of warrant per share | $ 2.568 | |||||||||||||||
July 2022 Offering [Member] | Series A Warrants and Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Expected volatility | 79.28% | |||||||||||||||
Risk-free interest rate | 3.06% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years 6 months | |||||||||||||||
July 2022 Offering [Member] | Series B Warrants and Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Expected volatility | 74.25% | |||||||||||||||
Risk-free interest rate | 3.16% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 1 year 6 months | |||||||||||||||
Common Stock [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 1,774,309 | |||||||||||||||
Exercise price of warrant per share | $ 1,486 | |||||||||||||||
Warrants to purchase common stock | 68 | |||||||||||||||
Warrant expiration date | Jul. 03, 2023 | |||||||||||||||
Number of fully vested options outstanding | 129,006 | 218,919 | 129,006 | |||||||||||||
Common Stock [Member] | December 2021 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 411,764 | |||||||||||||||
Warrants to purchase common stock | 411,766 | 247,059 | ||||||||||||||
Exercise price of warrant per share | $ 8.5 | $ 8.5 | ||||||||||||||
Common stock reserved for issuance | 164,707 | |||||||||||||||
Offering price per share | $ 8.5 | |||||||||||||||
Warrants exercisable expiration period | 5 years 6 months | |||||||||||||||
Warrants exercised | 0 | |||||||||||||||
Common Stock [Member] | Black-Scholes Option Pricing Model [Member] | December 2021 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 100,000 | |||||||||||||||
Expected volatility | 79.81% | |||||||||||||||
Risk-free interest rate | 1.21% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years 6 months | |||||||||||||||
Common Stock [Member] | Placement Agent Warrants [Member] | December 2021 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 20,590 | |||||||||||||||
Exercise price of warrant per share | $ 10.626 | $ 10.626 | ||||||||||||||
Proceeds from the issuance of common stock, net of issuance costs | $ 3,500,000 | |||||||||||||||
Placement agent's fees and other offering expenses | $ 500,000 | |||||||||||||||
Common stock reserved for issuance | 20,590 | |||||||||||||||
Percentage of warrant coverage | 5% | |||||||||||||||
Warrants exercisable expiration period | 5 years 6 months | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 336,060 | |||||||||||||||
Exercise price of warrant per share | $ 20 | |||||||||||||||
Gross proceeds from warrant exercise | $ 6,800,000 | |||||||||||||||
Proceeds from the issuance of common stock, net of issuance costs | $ 14,000,000 | |||||||||||||||
Placement agent's fees and other offering expenses | 1,900,000 | |||||||||||||||
Issuance of common stock for warrant exercises, shares | 336,060 | |||||||||||||||
Common stock reserved for issuance | 387,565 | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 7,200,000 | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | Placement Agent Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 35,000 | |||||||||||||||
Warrant exercisable period | 5 years | |||||||||||||||
Exercise price of warrant per share | $ 25 | $ 25 | ||||||||||||||
Common stock reserved for issuance | 11,375 | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 300,000 | |||||||||||||||
Expected volatility | 80.08% | |||||||||||||||
Risk-free interest rate | 0.38% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | Public Offering of Common Stock [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 580,000 | |||||||||||||||
Number of prefunded warrants to be issued | 120,000 | |||||||||||||||
Warrants to purchase common stock | 700,000 | |||||||||||||||
Combined purchase price of one share of common stock and accompanying warrant | $ 20 | |||||||||||||||
Combined purchase price of one pre-funded warrant and accompanying warrant | $ 19.998 | |||||||||||||||
Warrant exercisable period | 5 years | |||||||||||||||
Exercise price of warrant per share | $ 20 | |||||||||||||||
Common Stock [Member] | January 2021 Offering [Member] | Public Offering of Common Stock [Member] | Pre-funded Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Exercise price of warrant per share | $ 0.002 | |||||||||||||||
Common Stock [Member] | June 2021 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 298,865 | |||||||||||||||
Warrants to purchase common stock | 239,093 | 148,183 | ||||||||||||||
Exercise price of warrant per share | $ 20 | $ 20 | ||||||||||||||
Common stock reserved for issuance | 90,910 | |||||||||||||||
Offering price per share | $ 22 | |||||||||||||||
Percentage of warrant coverage | 80% | |||||||||||||||
Warrants exercisable expiration period | 5 years 6 months | |||||||||||||||
Warrants exercised | 0 | |||||||||||||||
Common Stock [Member] | June 2021 Offering [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 3,000,000 | |||||||||||||||
Expected volatility | 81.44% | |||||||||||||||
Risk-free interest rate | 0.88% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years 6 months | |||||||||||||||
Common Stock [Member] | June 2021 Offering [Member] | Placement Agent Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 14,946 | |||||||||||||||
Exercise price of warrant per share | $ 27.5 | $ 27.5 | ||||||||||||||
Proceeds from the issuance of common stock, net of issuance costs | $ 6,600,000 | |||||||||||||||
Placement agent's fees and other offering expenses | $ 900,000 | |||||||||||||||
Common stock reserved for issuance | 14,946 | |||||||||||||||
Percentage of warrant coverage | 5% | |||||||||||||||
Warrants exercisable expiration period | 5 years | |||||||||||||||
Common Stock [Member] | June 2021 Offering [Member] | Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 200,000 | |||||||||||||||
Expected volatility | 80.15% | |||||||||||||||
Risk-free interest rate | 0.77% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Issuance of common stock, net of issuance costs, shares | 1,774,309 | |||||||||||||||
Exercise price of warrant per share | $ 2.568 | |||||||||||||||
Common stock reserved for issuance | 3,996,418 | |||||||||||||||
Warrants exercised | 0 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Pre-funded Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 1,774,309 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Placement Agent Warrants [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Exercise price of warrant per share | $ 3.5225 | |||||||||||||||
Common stock reserved for issuance | 124,202 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 200,000 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Series A Warrant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants exercisable expiration period | 5 years 6 months | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Series A Warrant [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 3,800,000 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Series B Warrant [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants exercisable expiration period | 1 year 6 months | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Series B Warrants and Placement Agent Warrants [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 2,300,000 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Private Placement [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Warrants to purchase common stock | 447,800 | 447,800 | 447,800 | |||||||||||||
Warrant exercisable period | 5 years 6 months | |||||||||||||||
Exercise price of warrant per share | $ 2.568 | |||||||||||||||
Offering price per share | $ 0.0316 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Private Placement [Member] | Maximum [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Exercise price of warrant per share | $ 34 | $ 34 | $ 34 | |||||||||||||
Warrant expiration date | Jun. 21, 2027 | |||||||||||||||
Common Stock [Member] | July 2022 Offering [Member] | Private Placement [Member] | Minimum [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Exercise price of warrant per share | $ 8.5 | $ 8.5 | $ 8.5 | |||||||||||||
Warrant expiration date | May 18, 2026 | |||||||||||||||
Amended Warrants [Member] | July 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 1,000,000 | |||||||||||||||
Expected volatility | 79.28% | |||||||||||||||
Risk-free interest rate | 3.06% | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Expected term | 5 years 6 months | |||||||||||||||
Estimated Fair Value of Original Warrants Immediately Prior to Warrants Amendments [Member] | July 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Aggregate value of warrants | $ 500,000 | |||||||||||||||
Expected dividend yield | 0% | |||||||||||||||
Estimated Fair Value of Original Warrants Immediately Prior to Warrants Amendments [Member] | July 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | Maximum [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Expected volatility | 83.34% | |||||||||||||||
Risk-free interest rate | 3.16% | |||||||||||||||
Expected term | 4 years 11 months 8 days | |||||||||||||||
Estimated Fair Value of Original Warrants Immediately Prior to Warrants Amendments [Member] | July 2022 Offering [Member] | Black-Scholes Option Pricing Model [Member] | Minimum [Member] | ||||||||||||||||
Class Of Stock [Line Items] | ||||||||||||||||
Expected volatility | 81.21% | |||||||||||||||
Risk-free interest rate | 3.06% | |||||||||||||||
Expected term | 3 years 10 months 2 days |
Stockholders' Equity - Summary
Stockholders' Equity - Summary of Stock Option Activity (Details) - 2017 and 2020 Plan [Member] - $ / shares | 9 Months Ended | 12 Months Ended |
Sep. 30, 2023 | Dec. 31, 2022 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Number of Options, Beginning balance | 113,279 | |
Number of Options, Granted | 472,454 | |
Number of Options, Cancelled / Forfeited | (371,301) | |
Number of Options, Ending balance | 214,432 | 113,279 |
Number of Options, Vested and exercisable | 22,912 | |
Weighted-Average Exercise Price, Beginning balance | $ 21.30 | |
Weighted-Average Exercise Price, Granted | 0.94 | |
Weighted-Average Exercise Price, Cancelled / Forfeited | 5.27 | |
Weighted-Average Exercise Price, Ending balance | 4.2 | $ 21.30 |
Weighted-Average Exercise Price, Vested and exercisable | $ 30.56 | |
Weighted-Average Remaining Contractual Term Outstanding | 9 years 3 months 14 days | 8 years 1 month 2 days |
Weighted-Average Remaining Contractual Term Outstanding, Vested and exercisable | 7 years 1 month 28 days |
Stockholders' Equity - Summar_2
Stockholders' Equity - Summary of Valuation of Stock Option Awards (Detail) | 9 Months Ended | |
Sep. 30, 2023 | Sep. 30, 2022 | |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract] | ||
Expected volatility | 93.53% | 78.95% |
Risk-free interest rate | 3.91% | 2.14% |
Expected option life (in years) | 6 years 10 days | 6 years 7 days |
Stockholders' Equity - Summar_3
Stockholders' Equity - Summary of Compensation Cost Including Inducement Grant Expense Included in Condensed Consolidated Statements of Operations for Stock-based Compensation Arrangements (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | ||
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Compensation cost | $ (7) | $ 133 | $ 444 | $ 413 |
General and Administrative [Member] | ||||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Compensation cost | 6 | 121 | 415 | 388 |
Research and Development [Member] | ||||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||||
Compensation cost | $ (13) | $ 12 | $ 29 | $ 25 |
Stockholders' Equity - Summar_4
Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Detail) - shares | Sep. 30, 2023 | Sep. 30, 2022 |
Class Of Stock [Line Items] | ||
Common stock warrants | 4,876,571 | 4,876,639 |
Common stock available for issuance under stock plans | 708,768 | 94,524 |
Total | 5,804,258 | 5,100,169 |
Common Stock [Member] | ||
Class Of Stock [Line Items] | ||
Common stock warrants | 68 | |
Common stock options issued and outstanding under stock plans | 218,919 | 129,006 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||||||||
Oct. 01, 2023 | Aug. 07, 2023 | Apr. 03, 2023 | Apr. 30, 2019 | Dec. 31, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2023 | Dec. 31, 2022 | Mar. 01, 2020 | Jul. 31, 2010 | |
Operating Leased Assets [Line Items] | ||||||||||||
Lease commencement date | Mar. 01, 2020 | |||||||||||
Lease expiration date | Aug. 31, 2031 | |||||||||||
Lessee, operating lease, existence of option to extend | false | |||||||||||
Rent abatement term | 7 months | |||||||||||
Tenant improvement allowance on modified lease | $ 2,200,000 | $ 2,200,000 | ||||||||||
Right-of-use asset | $ 4,658,000 | $ 4,500,000 | ||||||||||
Operating lease liability | 4,617,000 | $ 4,500,000 | ||||||||||
Issuance of preferred stock, value | $ 4,414,000 | $ (9,000) | ||||||||||
Severance payments obligations | 1,348,000 | 1,348,000 | 1,234,000 | |||||||||
Severance and retention payments | $ 600,000 | |||||||||||
PUR Biologics, LLC [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Upfront cash paid | $ 500,000 | |||||||||||
Amount forgiven | 22,000 | |||||||||||
Repayments of outstanding payable assumed | 23,000 | |||||||||||
Development Assets [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Milestone and royalty payment obligations | $ 400,000 | |||||||||||
Percentage of royalties on net sales | 5% | |||||||||||
Development Assets [Member] | Commercialization Milestone [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Milestone and royalty payment obligations | $ 400,000 | |||||||||||
Development Assets [Member] | Product [Member] | Estimated Sales [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Revenue target for milestone achievement | $ 500,000 | |||||||||||
Series D Convertible Preferred Stock [Member] | Development Assets [Member] | PUR Biologics, LLC [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Issuance of preferred stock, shares | 8,366 | |||||||||||
Issuance of preferred stock, value | $ 1,750,000 | |||||||||||
Contingent Liability [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Payment for milestone | 0 | 0 | 0 | |||||||||
JHU License Agreement [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Royalty payments | $ 300,000 | |||||||||||
Selling expense | 6,000 | 112,000 | ||||||||||
Collaboration Agreement with Amerimmune [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Payment for milestone | 0 | 0 | $ 0 | |||||||||
Lease Termination Agreement [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Lease expiration date | Aug. 31, 2023 | |||||||||||
Lease termination fees | $ 1,000,000 | |||||||||||
Gain (loss) on termination of lease agreement | (1,000,000) | |||||||||||
Lease Termination Agreement [Member] | Scenario Forecast [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Reclassification of restricted cash to cash and cash equivalents | $ 300,000 | |||||||||||
Lease Termination Agreement [Member] | General and Administrative Expense [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Gain (loss) on termination of lease agreement | (29,000) | |||||||||||
Office Equipment [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Lease termination fees | 14,000 | |||||||||||
Building Improvements [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Increase (decrease) in operating lease liability | 400,000 | |||||||||||
Increase (decrease) in right-of-use-asset | $ 400,000 | |||||||||||
Extension of rent abatement | 2 months | |||||||||||
Amendment [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Tenant improvement allowance on modified lease | 2,300,000 | $ 2,300,000 | ||||||||||
Increase (decrease) in operating lease liability | 300,000 | |||||||||||
Increase (decrease) in right-of-use-asset | 300,000 | |||||||||||
Letter of Credit [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Security deposit | 300,000 | 300,000 | ||||||||||
Letter of credit | 300,000 | 300,000 | ||||||||||
Letter of Credit [Member] | Amendment [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Letter of credit | 400,000 | 400,000 | ||||||||||
Maximum [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Tenant improvement allowance on modified lease | 2,200,000 | 2,200,000 | ||||||||||
Maximum [Member] | Development Assets [Member] | PUR Biologics, LLC [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Potential cash payout | $ 6,250,000 | |||||||||||
Related Party [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Payment to related party | $ 18,000,000 | |||||||||||
Johns Hopkins University [Member] | Maximum [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Milestone Payment | $ 2,100,000 | |||||||||||
Severance Payments Obligations [Member] | ||||||||||||
Operating Leased Assets [Line Items] | ||||||||||||
Severance payments obligations | $ 700,000 | $ 700,000 |
Commitments and Contingencies_2
Commitments and Contingencies - Summary of Changes in ROU Assets (Detail) $ in Thousands | 9 Months Ended |
Sep. 30, 2023 USD ($) | |
Commitments and Contingencies Disclosure [Abstract] | |
Operating lease ROU assets at January 1, 2023 | $ 4,658 |
Amortization of operating lease ROU assets | (223) |
Write off of ROU asset due to lease termination | $ (4,435) |
Commitments and Contingencies_3
Commitments and Contingencies - Summary of Changes in Lease Liabilities (Detail) $ in Thousands | 9 Months Ended |
Sep. 30, 2023 USD ($) | |
Commitments and Contingencies Disclosure [Abstract] | |
Operating lease liabilities at January 1, 2023 | $ 4,617 |
Principal payments on operating lease liabilities | (154) |
Write off of lease liability due to lease termination | $ (4,463) |
Related Parties - Additional In
Related Parties - Additional Information (Detail) - Lordship Ventures Histogen Holdings LLC [Member] - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended | ||
Nov. 30, 2012 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | |
Related Party Transaction [Line Items] | ||||||
Percentage of outstanding voting shares controlled | 2.80% | 2.80% | ||||
Success Fee Agreement [Member] | ||||||
Related Party Transaction [Line Items] | ||||||
Minimum percentage of asset or equity engaged in merger or sale transaction | 90% | |||||
Related party expense recognized | $ 0 | $ 0 | $ 0 | $ 375 | ||
Allergan License Agreements [Member] | ||||||
Related Party Transaction [Line Items] | ||||||
Amount due to related parties | $ 9 | $ 9 | $ 10 | |||
Private Histogen [Member] | Success Fee Agreement [Member] | ||||||
Related Party Transaction [Line Items] | ||||||
Description of related party transaction | 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 generated from their Human Multipotent Cell Conditioned Media, or CCM, and their Human Extracellular Matrix, or hECM, in connection with the Company’s biologics technology platform. 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. | |||||
Private Histogen [Member] | Success Fee Agreement [Member] | Product Revenue [Member] | ||||||
Related Party Transaction [Line Items] | ||||||
Success fee percentage to be paid on certain product revenues | 1% | |||||
Private Histogen [Member] | Success Fee Agreement [Member] | License and Royalty Revenue [Member] | ||||||
Related Party Transaction [Line Items] | ||||||
Success fee percentage to be paid on certain license and royalty revenues | 10% |
Subsequent Events - Additional
Subsequent Events - Additional Information (Details) - Subsequent Event [Member] $ in Millions | Oct. 03, 2023 USD ($) |
Subsequent Event [Line Items] | |
Payment receivable from sale of assets | $ 2.1 |
Lordship Agreement [Member] | |
Subsequent Event [Line Items] | |
Termination fee | $ 0.4 |