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NanoTx License Agreement - Additional Information (Details) - USD ($) | May 07, 2020 | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Common stock, shares issued (in shares) |  | 15,360,025 | 6,749,028
Common stock, $0.001 par value; 100,000,000 shares authorized; 15,360,025 and 6,749,028 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively | $ 781,000 | $ 15,000 | $ 7,000
Nano Tx Licenses Agreement [Member] |  |  |
License fee payment in cash | $ 400,000 |  |
Common stock, shares issued (in shares) | 230,769 |  |
Nano Tx Licenses Agreement [Member] | Development And Sales Milestone [Member] |  |  |
Milestone payments | $ 136,500,000 |  |

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