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v3.23.2

LIQUIDITY AND CAPITAL RESOURCES (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2023 USD ($) shares | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) shares | Jun. 30, 2022 USD ($) | Jul. 13, 2023 USD ($) shares | Apr. 05, 2023 USD ($) | Dec. 31, 2022 USD ($) | Oct. 31, 2022 USD ($) ft²
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |  |
Cash | $ 1,837 |  | $ 1,837 |  |  |  | $ 11,446 |
Accumulated deficit | (175,229) |  | (175,229) |  |  |  | $ (165,297) |
Net loss | $ (4,508) | $ (3,398) | (9,924) | $ (12,773) |  |  |  |
Net cash used in operating activities |  |  | $ (9,921) | $ (9,425) |  |  |  |
New Facility Lease [Abstract] |  |  |  |  |  |  |  |
Area of premises | ft² |  |  |  |  |  |  |  | 45,500
Letter of credit |  |  |  |  |  |  |  | $ 4,100
Restricted cash |  |  |  |  |  |  |  | $ 4,100
Lincoln Park [Member] |  |  |  |  |  |  |  |
New Facility Lease [Abstract] |  |  |  |  |  |  |  |
Common stock shares issued and sold (in shares) | shares | 214,000 |  | 214,000 |  |  |  |  |
Gross proceeds from sale of equity | $ 300 |  | $ 300 |  |  |  |  |
Lincoln Park [Member] | Maximum [Member] |  |  |  |  |  |  |  |
New Facility Lease [Abstract] |  |  |  |  |  |  |  |
Aggregate gross purchase price |  |  |  |  |  | $ 10,000 |  |
Subsequent Event [Member] | Purchase Agreements [Member] |  |  |  |  |  |  |  |
Private Placement Offerings [Abstract] |  |  |  |  |  |  |  |
Aggregate principal convertible promissory notes |  |  |  |  | $ 8,700 |  |  |
Warrants to purchase common shares (in shares) | shares |  |  |  |  | 6,100,000 |  |  |
Annual interest rate on convertible notes payable |  |  |  |  | 6.00% |  |  |

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