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Summary of Significant Accounting Policies (Policies) | 9 Months Ended
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Sep. 30, 2025
Summary of Significant Accounting Policies |
Interim Financial Statements | Interim Financial Statements The summary of significant accounting policies is included in the Company’s audited consolidated financial statements and related notes as of and for the year ended December 31, 2024 found in the Annual Report on Form 10-K filed with the SEC on March 31, 2025. The accompanying unaudited interim consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). Any references in these notes to applicable guidance are meant to refer to GAAP as found in Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) promulgated by the Financial Accounting Standards Board (FASB). The accompanying unaudited interim consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. In the opinion of management, the accompanying unaudited interim consolidated financial statements include all normal and recurring adjustments (which consist primarily of accruals, estimates and assumptions that impact the unaudited interim consolidated financial statements) considered necessary to present fairly the Company’s financial position as of September 30, 2025 and its results of operations for the three and nine months ended September 30, 2025 and 2024. Operating results for the three and nine months ended September 30, 2025 are not necessarily indicative of the results that may be expected for the year ending December 31, 2025. The unaudited interim consolidated financial statements, presented herein, do not contain all of the required disclosures under GAAP for annual financial statements. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes as of and for the year ended December 31, 2024 found in the Company’s Annual Report on Form 10-K filed with the SEC on March 31, 2025.
Use of Estimates | Use of Estimates The preparation of unaudited interim consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited interim consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from such estimates. Estimates and assumptions are periodically reviewed, and the effects of revisions are reflected in the unaudited interim consolidated financial statements in the period they are determined to be necessary. Significant areas that require management’s estimates include stock-based compensation assumptions and accrued research and development.
Assets Held for Sale | Assets Held for Sale In March 2025, the Company committed to a plan to sell its remaining equipment and therefore has classified the amount as assets held for sale on the consolidated balance sheet as of September 30, 2025. The assets held for sale were reported at the lower of the carrying amount or fair value, less costs to sell.
Fair Value of Financial Instruments | Fair Value of Financial Instruments Management believes that the carrying amounts of the Company’s financial instruments, including cash equivalents and accounts payable, approximate fair value due to the short-term nature of those instruments. As of September 30, 2025, the Company no longer had funds in money market accounts.
Concentration of Credit Risk | Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant risk on its cash and cash equivalents.
Segment Information | Segment Information Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker (CODM), or decision-making group, in deciding how to allocate resources in assessing performance. The Company has one operating segment. The Company’s CODM is the chief executive officer. The Company’s CODM manages the Company’s operations on a consolidated basis for the purpose of allocating resources. The accounting policies of its segment are the same as those described in the summary of significant accounting policies. The CODM assesses performance for its segment based on net loss, which is reported on the consolidated statements of operations and comprehensive loss. The measure of segment assets is reported on the balance sheet as total assets. The CODM uses cash forecast models in deciding how to invest into the segment. The CODM analyzes the Company’s net loss and monitors budget versus actual results to assess the performance of the Company. The table below summarizes the significant expense categories regularly reviewed by the CODM for the three and nine months ended September 30, 2025 and 2024 (in thousands):
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Three Months Ended September 30, |  | Nine Months Ended September 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Collaboration revenues | ​ | $ | 45,250 | ​ | $ | 3,385 | ​ | $ | 48,979 | ​ | $ | 15,979
Less: | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​
Research and development, excluding facilities, personnel, depreciation and amortization expenses | ​ |  | (383) | ​ | ​ | 4,844 | ​ | ​ | 2,644 | ​ | ​ | 22,678
General and administrative, excluding facilities and personnel expenses, depreciation and amortization expenses | ​ |  | (47) | ​ | ​ | 1,561 | ​ | ​ | 5,210 | ​ | ​ | 9,287
Facilities expense | ​ |  | 81 | ​ | ​ | 1,302 | ​ | ​ | 1,836 | ​ | ​ | 4,728
Personnel expense | ​ |  | 1,784 | ​ | ​ | 8,085 | ​ | ​ | 9,925 | ​ | ​ | 20,925
Depreciation, amortization and interest on finance and sale-leaseback lease liabilities | ​ |  | 1 | ​ | ​ | 613 | ​ | ​ | 751 | ​ | ​ | 2,951
Other segment items(a) | ​ |  | (903) | ​ | ​ | (318) | ​ | ​ | 2,936 | ​ | ​ | (1,748)
Net income (loss) | ​ | $ | 44,717 | ​ | $ | (12,702) | ​ | $ | 25,677 | ​ | $ | (42,842)
(a)“Other segment items” includes (gain)/loss on sale of held for sale assets, loss on abandonment of operating lease right-of-use assets, and other income, net.
Net Loss Per Share | ​ Net Income (Loss) Per Share Basic net income (loss) per share of common stock is computed by dividing net income (loss) by the weighted-average number of shares of common stock outstanding during each period. Diluted net income (loss) per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible preferred stock and stock options, which would result in the issuance of incremental shares of common stock. Basic and diluted earnings per share (EPS) for the three and nine months ended September 30, 2025 and 2024 were calculated as follows (in thousands, except share and per share data): ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended September 30, | ​ | Nine Months Ended September 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Numerator: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Net income (loss) | ​ | $ | 44,717 | ​ | $ | (12,702) | ​ | $ | 25,677 | ​ | $ | (42,842)
Denominator: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Basic weighted-average common shares outstanding | ​ |  | 41,788,096 | ​ |  | 41,588,035 | ​ |  | 41,782,530 | ​ |  | 41,357,528
Effect of dilutive securities | ​ |  | 152,196 | ​ |  | — | ​ |  | 153,850 | ​ |  | —
Diluted weighted-average common shares outstanding | ​ |  | 41,940,292 | ​ |  | 41,588,035 | ​ |  | 41,936,380 | ​ |  | 41,357,528
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Basic and Diluted EPS | ​ | $ | 1.07 | ​ | $ | (0.31) | ​ | $ | 0.61 | ​ | $ | (1.04)
Anti-dilutive potential common shares excluded from the EPS computation above | ​ |  | 6,267,026 | ​ |  | 8,777,638 | ​ |  | 6,267,026 | ​ |  | 8,777,638
​ The following potentially dilutive securities have been excluded from the computation of diluted weighted-average shares of common stock outstanding, as they would be anti-dilutive:
​ | ​ | ​ | ​ | ​
​ |  | September 30, |  | September 30,
​ |  | 2025 | ​ | 2024
Stock options |  | 6,267,026 |  | 8,777,638
Recently Issued Accounting Pronouncements | Recently Issued Accounting Pronouncements In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (ASU 2023-09), which expands the disclosures required for income taxes. This ASU is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. The amendment should be applied on a prospective basis while retrospective application is permitted. The Company is currently evaluating the effect of this pronouncement on its disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which is intended to provide more detailed information about specified categories of expenses (purchases of inventory, employee compensation, depreciation and amortization) included in certain expense captions presented on the consolidated statement of operations. The guidance in this ASU is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for periods after the effective date of this ASU or (2) retrospectively to all prior periods presented in the consolidated financial statements. The Company is currently evaluating the impact that the adoption of ASU 2024-03 will have on its consolidated financial statements and disclosures.

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