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Summary of Significant Accounting Policies (Policies) | 3 Months Ended
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Mar. 31, 2026
Accounting Policies [Abstract] |
Basis of Presentation | Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2026, the condensed consolidated statements of operations and comprehensive loss for the three months ended March 31, 2026 and 2025, the condensed consolidated statements of stockholders’ equity for the three months ended March 31, 2026 and 2025, and the results of its cash flows for the three months ended March 31, 2026 and 2025. The financial data and other information disclosed in these notes related to the three months ended March 31, 2026 and 2025 are also unaudited. The results for the three months ended March 31, 2026 are not necessarily indicative of results to be expected for the year ending December 31, 2026, any other periods, or any future year period. The Company has evaluated subsequent events through the date the condensed consolidated financial statements were issued. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the Securities and Exchange Commission (“SEC”) on March 27, 2026.
Segments | Segments Operating segments are identified as components of an entity for which separate discrete financial information is available and that is regularly reviewed by the chief operating decision maker, the Company’s Chief Executive Officer, in deciding how to allocate resources to an individual segment and in assessing performance. The Company has determined it operates in a single operating segment and has one operating segment. See Note 3 for further information.
Cash, Cash Equivalents, Restricted Cash, and Marketable Securities | Cash, Cash Equivalents, Restricted Cash, and Marketable Securities The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents include amounts invested in money market accounts. As of March 31, 2026, restricted cash consisted of a cash reserve allocated to future tax payments related to the 2024 Loan (as defined in Note 8) and credit card collateral. As of December 31, 2025, restricted cash consisted solely of a cash reserve allocated to future tax payments related to the 2024 Loan. There was $0.1 million and $0.2 million in restricted cash as of March 31, 2026 and December 31, 2025, respectively, on the Company’s condensed consolidated balance sheets.
Marketable Securities | The Company’s investments in marketable securities have been classified and accounted for as available-for-sale. The Company classifies its maturities as either short-term or long-term based on each instrument’s underlying contractual maturity date, which are carried at their fair values based on the quoted market prices of the securities. Unrealized gains and losses are reported as accumulated other comprehensive income (loss). Realized gains and losses on available-for-sale securities are included in net loss in the period earned or incurred. As of March 31, 2026 and December 31, 2025, marketable securities consisted of U.S. Treasury bills. The Company periodically reviews whether its securities may be other-than-temporarily impaired, including whether or not (i) the Company has the intent to sell the security or (ii) it is more likely than not that the Company will be required to sell the security before its anticipated recovery. If one of these factors is met, the Company will record an impairment loss associated with its impaired investment. The impairment loss will be recorded as a write-down of investments in the condensed consolidated balance sheets and a realized loss within other expense in the condensed consolidated statements of operations and comprehensive loss. As of March 31, 2026 and December 31, 2025, there were no impairment losses for the investments.
Assets Held for Sale | Assets Held for Sale The Company classifies long-lived assets or disposal groups to be sold as held for sale in the period in which all of the following criteria are met: management, having the authority to approve the action, commits to a plan to sell the asset or disposal group; the asset or disposal group is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such assets or disposal group; the sale of the asset or disposal group is probable, and transfer of the asset or disposal group is expected to qualify for recognition as a completed sale within one year, except if events or circumstances beyond the Company’s control extend the period of time required to sell the asset or disposal group beyond one year; and actions required to complete the plan to sell have been initiated. The Company initially measures a long-lived asset or disposal group that is held for sale at the lower of its carrying value or fair value less any costs to sell. Fair value is estimated by the Company through evaluations of quoted market prices received for other comparable held for sale assets sold by the Company. Any loss resulting from this measurement is recognized in the period in which the held for sale criteria are met. Conversely, gains are not recognized on the sale of a long-lived asset or disposal group until the date of sale. The Company assesses the fair value of a long-lived asset or disposal group less any costs to sell each reporting period it remains classified as held for sale and reports any subsequent changes as an adjustment to the carrying value of the asset or disposal group, as long as the new carrying value does not exceed the carrying value of the asset at the time it was initially classified as held for sale. Upon determining that a long-lived asset or disposal group meets the criteria to be classified as held for sale, the Company ceases depreciation and reports long-lived assets in the line item “assets held for sale” in its condensed consolidated balance sheets. In March 2025, the Company’s board of directors (the “Board of Directors”) approved a plan to sell the Tarzana facility. The Company engaged a broker to facilitate a potential sale of the Tarzana facility and therefore reclassified the land and building as held for sale in the condensed consolidated balance sheet during the year ended December 31, 2025. The Tarzana facility is currently leased to AstraZeneca Pharmaceuticals LP (“Tenant”) and Tenant has a right of first offer to purchase it. Refer to Note 8. In May 2026, the Company determined that there had been a change to its plan with respect to the Tarzana facility and the Board of Directors approved discontinuing the plan to market the Tarzana facility for sale. As a result, the Company determined that this asset no longer meets the criteria to be classified as held for sale under ASC 360. Consequently, in the second quarter of 2026, this asset will be reclassified as held and used at the lower of (a) its carrying amount before the asset was classified as held for sale, adjusted for depreciation expenses that would have been recognized had the asset been continuously classified as held and used, and (b) its fair value. The Company is currently evaluating the financial statement impact of this reclassification. The resulting adjustment will be recognized in the second quarter in the condensed consolidated statement of operations and comprehensive loss as a component of gain (loss) from operations.
Impairment of Long-Lived Assets | Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable or that the useful life is shorter than originally estimated. Recoverability of assets is measured by comparing the carrying amount of an asset to future undiscounted net cash flows expected to be generated by the asset over its remaining useful life. If such assets are impaired, the impairment recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. If the useful life is shorter than originally estimated, the Company depreciates or amortizes the remaining carrying value over the revised shorter useful life. See Note 12 for more information.
Research and Development Expenses | Research and Development Expenses Research and development costs are expensed as incurred. Clinical trial and other development costs incurred by third parties are expensed as the contracted work is performed. The Company accrues for costs incurred as the services are being provided by monitoring the status of the trial or project and the invoices received from its external service providers. The Company adjusts its accrual as actual costs become known. Where contingent milestone payments are due to third parties under research and development arrangements or license agreements, the milestone payment obligations are expensed when the milestone results are achieved.
Recent Accounting Pronouncements Not Yet Adopted | Recent Accounting Pronouncements Not Yet Adopted In November 2024, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40) (“ASU 2024-03”). The amendments in this update require disclosure, in the notes to the financial statements, of specific expense categories present within expense captions presented on the face of the income statement within continuing operations of public business entities. The amendments in this update are effective for annual periods beginning after December 15, 2026 and interim periods beginning after December 15, 2027. The Company is currently evaluating the impact of ASU 2024-03 on its consolidated financial statements and related disclosures. In September 2025, the FASB issued ASU No. 2025-07, Derivatives and Hedging and Revenue from Contracts with Customers - Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract (“ASU 2025-07”) which applies to all entities that enter into non-exchange-traded contracts with underlyings based on operations or activities specific to one of the parties to the contract. The new guidance excludes from derivative accounting non-exchange-traded contracts with underlyings that are based on operations or activities specific to one of the parties to the contract. ASU 2025-07 is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods. Early adoption is permitted. The Company does not expect adoption of ASU 2025-07 to have a material impact on its condensed consolidated financial statements and related disclosures. A variety of proposed or otherwise potential accounting standards are currently being studied by standard-setting organizations and certain regulatory agencies. Because of the tentative and preliminary nature of such proposed standards, the Company has not yet determined the effect, if any, that the implementation of such proposed standards would have on the Company’s consolidated financial statements.

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