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INDEBTEDNESS - Narrative (Details) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 03, 2025 USD ($) | Apr. 19, 2024 USD ($) | Jan. 29, 2024 USD ($) tranche $ / shares shares | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jul. 23, 2025 shares | Jul. 21, 2025 $ / shares shares | Feb. 28, 2025 $ / shares shares | Nov. 11, 2019 USD ($)
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] |  |  | Secured Overnight Financing Rate (SOFR) [Member] |  |  |  |  |  |  |
Warrant to purchase common stock (in shares) | shares |  |  | 3,076,923 |  |  |  | 1,408,588 | 2,115,384 | 1,153,846 |
Exercise price (in dollars per share) | $ / shares |  |  | $ 1.30 |  |  |  |  | $ 1.30 | $ 1.30 |
Warrant exercise period (in years) |  |  |  |  |  |  |  |  | 8 years |
Warrant liability |  |  |  | $ 2,980 | $ 5,176 |  |  |  |  |
Loss on extinguishment of debt |  |  |  | $ 0 | 517 | $ 0 |  |  |  |
Secured Debt | Term Loan Facility | Line of Credit |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  | $ 55,000 |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity, number of available tranches | tranche |  |  | 3 |  |  |  |  |  |  |
Variable rate, floor (as percent) |  |  | 4.25% |  |  |  |  |  |  |
Basis spread on variable rate (as percent) |  |  | 6.75% |  |  |  |  |  |  |
Debt instrument, cap rate (as percent) |  |  | 15.00% |  |  |  |  |  |  |
Debt instrument, interest rate (as percent) |  |  |  | 11.00% |  |  |  |  |  |
Interest expense |  |  |  | $ 8,400 | 7,100 |  |  |  |  |
Annual interest rate, increase (as percent) |  |  | 3.00% |  |  |  |  |  |  |
Late fee percentage |  |  | 2.00% |  |  |  |  |  |  |
Exit fee percentage |  |  | 0.75% |  |  |  |  |  |  |
Debt covenant, cash and cash equivalents |  |  | $ 15,000 |  |  |  |  |  |  |
Debt covenant, revenue period (in months) |  |  | 12 months |  |  |  |  |  |  |
Debt covenant, revenue |  |  | $ 150,000 |  |  |  |  |  |  |
Secured Debt | Term Loan Facility | Line of Credit | Minimum |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Transaction fee percentage |  |  | 1.00% |  |  |  |  |  |  |
Prepayment fee percentage |  |  | 1.00% |  |  |  |  |  |  |
Secured Debt | Term Loan Facility | Line of Credit | Maximum |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Transaction fee percentage |  |  | 1.25% |  |  |  |  |  |  |
Prepayment fee percentage |  |  | 4.00% |  |  |  |  |  |  |
Secured Debt | Term Loan Facility, Tranche A | Line of Credit |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  | $ 37,000 |  |  |  |  |  |  |
Proceeds from line of credit |  |  | 34,500 |  |  |  |  |  |  |
Secured Debt | Term Loan Facility, Tranche B | Line of Credit |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  | $ 8,000 |  |  |  |  |  |  |  |
Proceeds from line of credit |  | $ 7,500 |  |  |  |  |  |  |  |
Secured Debt | Term Loan Facility, Tranche C | Line of Credit |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity | $ 10,000 |  |  |  |  |  |  |  |  |
Proceeds from line of credit | $ 9,300 |  |  |  |  |  |  |  |  |
Term Loan | Tranche A and B | Keryx | Biopharma Credit Investments V (Master) LP | Collateral Agent, Pharmakon |  |  |  |  |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit, maximum borrowing capacity |  |  |  |  |  |  |  |  |  | $ 100,000
Interest expense |  |  |  |  | 0 | $ 6,000 |  |  |  |
Extinguishment of debt |  |  | 35,000 |  |  |  |  |  |  |
Payment of outstanding debt interest and prepayment fee |  |  | $ 200 |  |  |  |  |  |  |
Loss on extinguishment of debt |  |  |  |  | $ 500 |  |  |  |  |

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