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Commitments and Contingencies - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Jun. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Commitments and Contingencies |  |  |  |  |
Loss on abandonment of operating lease right-of-use asset | $ 0 | $ 900,000 | $ 0 | $ 927,000 | $ 0
Amount of gain (loss) recognized | 400,000 |  |  | 600,000 |
Gain on sale of sale-leaseback |  |  |  | 0 | $ (82,000)
Loss contingency, estimate of possible loss | 1,900,000 |  |  | 1,900,000 |
Penn | Penn License Agreement |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Annual payments to be made |  |  |  | 25,000 |
Additional milestone payments for first CAR-M product |  |  |  | 1,700,000 |
Penn | Penn License Agreement | Maximum |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Milestone payments | 10,900,000 |  |  | 10,900,000 |
Additional milestone payments |  |  |  | 30,000,000 |
Laboratory Equipment |  |  |  |  |
Commitments and Contingencies |  |  |  |  |
Gain (loss) on termination of finance lease recognized | $ 100,000 |  |  | $ (1,700,000) |

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