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Summary of Significant Accounting Policies - Summary of Segment Profit or Loss Including Significant Segment Expenses (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2026 | Mar. 31, 2025
Segment Reporting Information, Profit (Loss) [Abstract] |  |  |
Collaboration revenue |  | $ 1,046 | $ 3,674
Less: |  |  |
Compensation and benefits |  | 8,248 | 16,557
Lab expenses and outside research services |  | 3,447 | 3,224
Clinical supply costs |  | 1,379 | 3,074
Clinical trials |  | 3,384 | 7,013
Support functions |  | 6,300 | 8,286
Other segment expenses | [1] | 3,207 | 10,215
Total operating expenses |  | 25,965 | 48,369
Loss from operations |  | (24,919) | (44,695)
Other income, net |  | 1,989 | 4,224
Loss before income taxes |  | $ (22,930) | $ (40,471)
[1] | Other segment expenses include consultants & contractor expense, contra-R&D expense for GSK collaboration, depreciation expense, impairment loss, restructuring expense, and stock-based compensation expense.

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