DEBT - Additional Information (Details) - USD ($)		9 Months Ended
Jun. 01, 2022	Sep. 30, 2020
Debt Instrument [Line Items]
Debt discount for term loan		$ 1,115,000
Hercules and Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under term loan		$ 75,000,000
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 September 30, 2020) less 3.25%
Term loan maturity date		Oct. 01, 2024
Percentage added to prime rate for debt instrument interest rate		9.00%
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		$ 30,000,000
Additional percentage of interest on past due amounts		5.00%
Hercules and Silicon Valley Bank [Member] \| Scenario Forecast [Member]
Debt Instrument [Line Items]
Debt covenant minimum cash balance	$ 25,000,000
Hercules and Silicon Valley Bank [Member] \| Tranche A [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under term loan		$ 35,000,000
Principal amount outstanding under Tranche A term loan		25,000,000
Unused amount under Tranche A term loan		$ 10,000,000
Expiration date to borrow under a tranche for a debt instrument		Jun. 15, 2021
Minimum interest rate (as a percentage)		9.00%
Carrying value of term loan, net		$ 23,885,000
Debt discount for term loan		445,000
Debt issuance costs for term loan		670,000
Accrued interest expense		6,000
Accrued end of term charge		0
Hercules and Silicon Valley Bank [Member] \| Tranche B [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity under term loan		$ 15,000,000
Expiration date to borrow under a tranche for a debt instrument		Dec. 15, 2021
Start date to borrow under a tranche for a debt instrument		Jan. 01, 2021
Hercules and Silicon Valley Bank [Member] \| 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

Accrued end of term charge.

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First date to available to drawdown any amount under a tranche.

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Debt Covenant Minimum Cash Balance

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Percentage of outstanding loan amount payable upon maturity.

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Minimum amount allowed to be prepaid under debt instrument.

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Last date to drawdown any amounts under a tranche.

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Added percentage to current interest rate under debt instrument to past due amounts.

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Percentage of prepayment amount to be paid upon prepayment under debt instrument.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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.

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Description of any adjustments made to the stated rate to determine the effective rate.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Amount, after accumulated amortization, of debt discount.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Description of long-term debt arrangements, which are debt arrangements that originally require full repayment more than twelve months after issuance or greater than the normal operating cycle of the company, if longer, and disclosures pertaining to the underlying arrangements, including repayment terms, conversion features, interest rates, restrictions on assets and activities, debt covenants, and other matters important to users of the financial statements. Types of long-term debt arrangements include borrowing under notes payable, bonds payable, debentures, term loans, and other contractual obligations for payment.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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