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Leases - Additional Information (Detail) |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Nov. 04, 2025 Lease | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024
Lessee Lease Description [Line Items] |  |  |  |  |  |
Number of operating leases | Lease | 3 |  |  |  |  |
Lessee, operating lease, expiration period | We currently have three operating leases for administrative and research and development office and lab space in San Diego, California and Boston, Massachusetts that expire between November 2025 and May 2033. |  |  |  |  |
Lease agreement additional extended lease term |  | 5 years |  | 5 years |  |
Weighted-average discount rate |  | 12.30% |  | 12.30% |  | 11.40%
Weighted-average remaining lease term |  | 6 years 4 months 24 days |  | 6 years 4 months 24 days |  | 5 years 10 months 24 days
Total cash paid for amounts included in the measurement of lease liabilities |  | $ 500,000 | $ 300,000 | $ 1,400,000 | $ 1,300,000 |
ROU assets obtained in exchange for operating lease liabilities |  |  |  | 2,700,000 | 0 |
ASC 842 |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Total operating lease rent expense |  | 800,000 | $ 500,000 | 2,400,000 | $ 1,500,000 |
San Diego Corporate Headquarters Lease |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Reimbursements for tenant improvements and rent credits |  |  |  | 1,300,000 |  |
Boston Lease |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Reimbursements for tenant improvements and rent credits |  |  |  | 1,400,000 |  |
2025 San Diego Corporate Headquarters Lease |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |
Rent credit to be applied as credit, in equal monthly installments |  |  |  | 2,400,000 |  |
Lease allowance |  | $ 6,200,000 |  | $ 6,200,000 |  |

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