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LEASES - Narrative (Details) $ in Thousands | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2025 USD ($) ft² | Dec. 31, 2024 USD ($) | Jul. 30, 2024 ft² | Jul. 01, 2024 USD ($) | Sep. 07, 2021 ft²
Lessee, Lease, Description [Line Items] |  |  |  |  |
Lessee, area of sublease | ft² |  |  | 20,000 |  |
Waltham lease for additional period | 5 years |  |  |  |
Operating lease right-of-use assets | $ 16,841 | $ 19,251 |  |  |
Total operating lease liabilities | 16,883 |  |  |  |
Lessee, operating lease, term of contract |  |  |  | 5 years 3 months |
Accent Therapeutics, Inc |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Letters of credit outstanding, amount | 200 |  |  |  |
Phase A Premises |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Lessee, area of sublease | ft² |  |  |  |  | 35,662
Waltham Lease |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |
Lessee, operating lease, monthly base rent | $ 200 |  |  |  |
Operating lease, period for improvement | 8 years 4 months |  |  |  |
Percentage of annual increase in operating lease | 3.00% |  |  |  |
Letters of credit outstanding, amount | $ 1,200 |  |  |  |
Operating lease right-of-use assets | $ 5,700 |  |  |  |
Total operating lease liabilities |  |  |  | $ 5,700 |
Lessee, operating lease, monthly base rent per square foot | ft² | 71.00 |  |  |  |
Lessee, operating lease, area of rental space | ft² | 17,500 |  |  |  |

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