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v3.23.1

Liquidity and Capital Resources (Details) |  |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Dec. 02, 2022 USD ($) | Nov. 23, 2022 $ / shares shares | Jul. 12, 2022 USD ($) $ / shares | Mar. 06, 2022 USD ($) $ / shares shares | Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) $ / shares | Oct. 18, 2022 USD ($) ft²
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Cash |  |  |  |  | $ 11,446,000 | $ 16,985,000 |
Accumulated deficit |  |  |  |  | (165,297,000) | (140,702,000) |
Net loss |  |  |  |  | (24,579,000) | (122,545,000) |
Net cash used in operating activities |  |  |  |  | $ (20,976,000) | $ (23,488,000) |
Common stock, par value (in dollars per share) | $ / shares |  |  |  |  | $ 0.005 | $ 0.005 |
Aggregate gross purchase price |  |  |  |  | $ 12,000,000 |  |
New Facility Lease [Abstract] |  |  |  |  |  |  |
Area of office and laboratory space | ft² |  |  |  |  |  |  | 45,500
Letter of credit |  |  |  |  |  |  | $ 4,100,000
Restricted cash |  |  |  |  | $ 4,100,000 |  | $ 4,100,000
Common Warrants [Member] |  |  |  |  |  |  |
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  | $ 38.2 |  |  |
Warrant exercisable term |  |  |  |  | 6 months |  |
Warrant expiration term |  |  |  |  | 5 years 6 months |  |
Pre-funded Warrants [Member] |  |  |  |  |  |  |
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  | $ 0.125 |  |  |  |  |
PIPE Investor [Member] |  |  |  |  |  |  |
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Private placement (in shares) | shares |  | 2,185,000 |  | 343,000 |  |  |
Common stock, par value (in dollars per share) | $ / shares |  |  |  | $ 0.005 |  |  |
Number of common stock (in shares) | shares |  |  |  | 1 |  |  |
Unit price (in dollars per share) | $ / shares |  | $ 3.53 |  |  |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  |  | $ 0.1 |  |  |
Aggregate gross purchase price |  |  |  | $ 12,000,000 |  |  |
Proceeds from issuance of warrants to purchase of common stock | $ 7,700,000 |  |  |  |  |  |
Warrant exercisable term |  |  |  | 6 months |  |  |
Warrant expiration term |  |  |  | 5 years 6 months |  |  |
PIPE Investor [Member] | Common Warrants [Member] |  |  |  |  |  |  |
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Private placement (in shares) | shares |  |  |  | 343,000 |  |  |
Number of common stock (in shares) | shares |  | 1 |  | 1 |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  | $ 3.28 |  |  |  |  |
Aggregate gross purchase price |  |  |  | $ 12,000,000 |  |  |
Warrant exercisable term |  |  |  |  | 6 months |  |
Warrant expiration term |  |  |  |  | 5 years 6 months |  |
PIPE Investor [Member] | Pre-funded Warrants [Member] |  |  |  |  |  |  |
Liquidity and Capital Resources [Abstract] |  |  |  |  |  |  |
Private placement (in shares) | shares |  |  |  | 68,000 |  |  |
Number of common stock (in shares) | shares |  | 2 |  | 1 |  |  |
Warrant exercise price (in dollars per share) | $ / shares |  |  | $ 0.1 |  |  |  |
Proceeds from issuance of warrants to purchase of common stock |  |  | $ 7,000 |  |  |  |

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