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DEBT - Additional Information (Details) - USD ($) |  | 6 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2024 | Sep. 30, 2020 | Dec. 31, 2023 | Sep. 15, 2023
Debt Instrument [Line Items] |  |  |  |  |
Principal amount outstanding under term loan |  | $ 95,433,000 |  |  |
Hercules and Silicon Valley Bank [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum borrowing capacity under term loan | $ 125,000,000 |  | $ 75,000,000 |  |
Principal amount outstanding under term loan |  | 80,000,000 |  |  |
Carrying value of term loan, net |  | 83,400,000 |  |  |
Unamortized debt discount and issuance costs |  | 331,000 |  |  |
Accrued end of term charge |  | $ 3,800,000 |  |  |
Percentage added to prime rate for debt instrument interest rate |  |  | 9.00% |  |
Description of maturity date terms for term loan |  |  | matures on October 1, 2025, or the Loan Maturity Date, which was extended from April 1, 2025 upon regulatory approval of RYTELO. |  |
Term loan maturity date |  |  | Oct. 01, 2025 |  |
Term loan interest rate description |  | The Loan Agreement bears interest at a floating rate per annum equal to the greater of either (i) 9.0% or (ii) the sum of (A) the Prime Rate (as reported in The Wall Street Journal) minus 4.5%, plus (B) 9.0% (8.5% as of December 31, 2023). |  |  |
Interest only period payment term description |  |  | The interest only period of the Loan Agreement has been extended from June 30, 2024 through December 31, 2024. due to regulatory approval of RYTELO and satisfaction of certain financial and capitalization requirements. Following the expiration of the interest-only period, we are required to repay the Loan Agreement in equal monthly amortization payments of principal and interest until the Loan Maturity Date. |  |
End of term charge for loan, percentage |  |  | 6.55% |  |
Minimum amount of prepayment allowed under debt instrument |  |  | $ 5,000,000 |  |
Description of term loan payment terms |  |  | At our option, upon at least five business days’ prior written notice to Hercules, we may prepay all or any portion greater than or equal to $5.0 million of the outstanding loan by paying the entire principal balance (or portion thereof) and all accrued and unpaid interest. There is no prepayment charge for prepayments of drawdowns under Tranche 1 or Tranche 2. Prepayments of drawdowns under Tranche 3, Tranche 4, Tranche 5 or Tranche 6 are subject to a prepayment charge of 1.5% of the prepayment amount, if the prepayment is made prior to June 30, 2025. Thereafter, any prepayment of Tranche 3, Tranche 4, Tranche 5 or Tranche 6 is not subject to a prepayment charge. |  |
Hercules and Silicon Valley Bank [Member] | Second Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt discount amount | 100,000 |  |  |  |
Hercules and Silicon Valley Bank [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principal amount outstanding under term loan |  |  | $ 80,000,000 |  |
Debt discount amount | $ 300,000 |  |  |  |
Principle amount |  |  | $ 125,000,000 |  |
Percentage added to prime rate for debt instrument interest rate |  |  | 9.00% |  |
Hercules and Silicon Valley Bank [Member] | Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  |  | 4.50% | 8.50% |
Hercules and Silicon Valley Bank [Member] | Minimum [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  |  | 4.50% |  |
Hercules and Silicon Valley Bank [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  |  | 9.00% |  |
Hercules and Silicon Valley Bank [Member] | Maximum [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate |  |  | 9.00% |  |
Hercules and Silicon Valley Bank [Member] | Tranche One [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 0.00% |  |  |  |
Hercules and Silicon Valley Bank [Member] | Tranche Two [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 0.00% |  |  |  |
Hercules and Silicon Valley Bank [Member] | Tranche Three [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |  |
Debt instrument face amount expired |  |  |  |  | $ 20,000,000
Hercules and Silicon Valley Bank [Member] | Tranche Four [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |  |
Principle amount |  |  | $ 30,000,000 |  |
Hercules and Silicon Valley Bank [Member] | Tranche Four [Member] | Minimum [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principle amount |  |  | 10,000,000 |  |
Hercules and Silicon Valley Bank [Member] | Tranche Four [Member] | Maximum [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Principle amount |  |  | 30,000,000 |  |
Hercules and Silicon Valley Bank [Member] | Tranche Five [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |  |
Principle amount |  |  | $ 20,000,000 |  |
Hercules and Silicon Valley Bank [Member] | Tranche Six [Member] | Third Amendment [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Prepayment charge (as a percentage) | 1.50% |  |  |  |

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