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License Agreement - Additional Information (Details) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
May 07, 2020 | Dec. 31, 2021 | Dec. 31, 2020
Common stock, shares issued (in shares) |  | 15,510,025 | 6,749,028
Common stock, $0.001 par value; 100,000,000 shares authorized; 15,510,025 and 6,749,028 shares issued and outstanding in 2021 and 2020, respectively |  | $ 16,000 | $ 7,000
UTHSA License Agreement [Member] |  |  |
License fee payment in cash |  | 250,000 |
License agreement maintenance fee |  | 50,000 |
UTHSA License Agreement [Member] | Development And Sales Milestone [Member] |  |  |
Milestone payments |  | $ 30,300,000 |
Nano Tx Licenses Agreement [Member] |  |  |
License fee payment in cash | $ 400,000 |  |
Common stock, shares issued (in shares) | 230,769 |  |
Common stock, $0.001 par value; 100,000,000 shares authorized; 15,510,025 and 6,749,028 shares issued and outstanding in 2021 and 2020, respectively | $ 781,000 |  |
Nano Tx Licenses Agreement [Member] | Development And Sales Milestone [Member] |  |  |
Milestone payments | $ 136,500,000 |  |

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