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DEBT - Additional Information (Details) - Hercules and Silicon Valley Bank [Member] - USD ($) |  |  | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 01, 2022 | Aug. 12, 2021 | Sep. 30, 2020 | Dec. 31, 2021 | Jun. 30, 2021
Debt Instrument [Line Items] |  |  |  |  |
Maximum borrowing capacity under term loan |  |  | $ 75,000,000 |  |
Principal amount outstanding under term loan |  |  |  | $ 50,000,000 |
Description of maturity date terms for term loan |  |  | The Term Loan matures on October 1, 2024, or the Loan Maturity Date, and may be extended up to an additional 12 months upon the achievement of certain clinical, regulatory and financial milestones. |  |
Term loan interest rate description |  |  |  | The Term Loan bears interest at a floating rate per annum equal to the greater of either (i) 9.0% or (ii) 9.0% plus the prime rate as reported in The Wall Street Journal (3.25% as of December 31, 2021) less 3.25%. |
Term loan maturity date |  |  | Oct. 01, 2024 |  |
Percentage added to prime rate for debt instrument interest rate |  |  | 9.00% |  |
Interest only period payment term description |  |  | Upon the achievement of certain clinical milestones, the interest-only period was extended for an additional six months until May 1, 2023. Upon the achievement of certain regulatory and financial milestones, the interest-only period may be extended for another six months until November 1, 2023 |  |
End of term charge for loan, percentage |  |  | 6.55% |  |
Minimum amount of prepayment allowed under debt instrument |  |  | $ 5,000,000 |  |
Prepayment charge (as a percentage) |  |  | 1.50% |  |
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 $5,000,000 of the outstanding loan by paying the entire principal balance (or portion thereof) and all accrued and unpaid interest. Such prepayment is subject to a prepayment charge of 1.5% of the prepayment amount, if the prepayment is made in any of the first 36 months following the Closing Date. Thereafter, any prepayment is not subject to a prepayment charge. |  |
Debt covenant minimum cash balance |  |  | $ 25,000,000 |  |
Debt covenant minimum cash balance upon licensing transaction |  | $ 35,000,000 | 30,000,000 |  |
Debt covenant minimum cash balance upon regulatory milestone achievement |  |  | $ 20,000,000 |  |
Additional percentage of interest on past due amounts |  |  | 5.00% |  |
Carrying value of term loan, net |  |  |  | $ 49,830,000 |
Unamortized debt discount and issuance costs |  |  |  | 863,000 |
Accrued end of term charge |  |  |  | 693,000 |
Scenario Forecast [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt covenant minimum cash balance | $ 30,000,000 |  |  |  |
Tranche A [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum borrowing capacity under term loan |  |  | $ 35,000,000 |  |
Principal amount outstanding under term loan |  |  | $ 25,000,000 |  | $ 10,000,000
Minimum interest rate (as a percentage) |  |  | 9.00% |  |
Tranche B [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum borrowing capacity under term loan |  |  | $ 15,000,000 |  |
Principal amount outstanding under term loan |  |  |  | $ 15,000,000 |
Minimum interest rate (as a percentage) |  |  | 9.00% |  |
Tranche C [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maximum borrowing capacity under term loan |  |  | $ 25,000,000 |  |
Expiration date to borrow under a tranche for a debt instrument |  |  | Dec. 31, 2022 |  |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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