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CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) | Common Stock | Additional Paid- in Capital | Accumulated Deficit | Total
--- | --- | --- | --- | ---
Beginning Balance at Dec. 31, 2019 | $ 45,728 | $ 371,573,909 | $ (327,533,414) | $ 44,086,223
Beginning Balance, Shares at Dec. 31, 2019 | 45,728,831 |  |  |
Warrants exercised for cash | $ 459 | 549,541 |  | 550,000
Warrants exercised for cash, shares | 458,334 |  |  |
Issuance of common stock as commitment fee for future financing | $ 345 | (345) |  |
Issuance of common stock as commitment fee for future financing (Shares) | 345,357 |  |  |
Stock-based compensation | $ 85 | 2,705,280 |  | 2,705,365
Stock-based compensation (in shares) | 85,110 |  |  |
Net loss |  |  | (12,827,343) | (12,827,343)
Ending Balance at Jun. 30, 2020 | $ 46,617 | 374,828,385 | (340,360,757) | 34,514,245
Ending Balance, Shares at Jun. 30, 2020 | 46,617,632 |  |  |
Beginning Balance at Mar. 31, 2020 | $ 46,532 | 373,467,697 | (334,019,058) | 39,495,171
Beginning Balance, Shares at Mar. 31, 2020 | 46,532,522 |  |  |
Stock-based compensation | $ 85 | 1,360,688 |  | 1,360,773
Stock-based compensation (in shares) | 85,110 |  |  |
Net loss |  |  | (6,341,699) | (6,341,699)
Ending Balance at Jun. 30, 2020 | $ 46,617 | 374,828,385 | (340,360,757) | 34,514,245
Ending Balance, Shares at Jun. 30, 2020 | 46,617,632 |  |  |
Beginning Balance at Dec. 31, 2020 | $ 50,731 | 383,533,326 | (356,239,484) | 27,344,573
Beginning Balance, Shares at Dec. 31, 2020 | 50,731,072 |  |  |
Issuance of common stock for cash (net of offering costs of $3.9 million) | $ 32,283 | 52,520,475 |  | 52,552,758
Issuance of common stock for cash (net of offering costs of $3.9 million), Shares | 32,282,857 |  |  |
Stock options exercised for cash | $ 2 | 3,085 |  | $ 3,087
Stock options exercised for cash (Shares) | 1,456 |  |  | 1,456
Stock-based compensation | $ 63 | 3,029,062 | 0 | $ 3,029,125
Stock-based compensation (in shares) | 63,290 |  |  |
Net loss | $ 0 | 0 | (19,686,232) | (19,686,232)
Ending Balance at Jun. 30, 2021 | $ 83,079 | 439,085,948 | (375,925,716) | 63,243,311
Ending Balance, Shares at Jun. 30, 2021 | 83,078,675 |  |  |
Beginning Balance at Mar. 31, 2021 | $ 83,014 | 437,430,839 | (365,018,934) | 72,494,919
Beginning Balance, Shares at Mar. 31, 2021 | 83,013,929 |  |  |
Stock options exercised for cash | $ 2 | 3,085 |  | 3,087
Stock options exercised for cash (Shares) | 1,456 |  |  |
Stock-based compensation | $ 63 | 1,652,024 | 0 | 1,652,087
Stock-based compensation (in shares) | 63,290 |  |  |
Net loss | $ 0 | 0 | (10,906,782) | (10,906,782)
Ending Balance at Jun. 30, 2021 | $ 83,079 | $ 439,085,948 | $ (375,925,716) | $ 63,243,311
Ending Balance, Shares at Jun. 30, 2021 | 83,078,675 |  |  |

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