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STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) | Class A Preferred Shares | Class A Common Shares | Common Shares | Common Stock Issuable | Additional Paid-in Capital | Accumulated Deficit | Total
--- | --- | --- | --- | --- | --- | --- | ---
Balances at Dec. 31, 2017 | $ 0 | $ 0 | $ 3,000 | $ 9,558,000 | $ 98,679,000 | $ (48,408,000) | $ 59,832,000
Balances (in shares) at Dec. 31, 2017 | 250,000 | 1,000,000 | 25,236,255 |  |  |  |
Common stock issuable - Founders Agreement | $ 0 | $ 0 | $ 0 | 2,085,000 | 0 | 0 | 2,085,000
Issuance of common shares - Founders Agreement | $ 0 | $ 0 | $ 0 | (9,558,000) | 9,558,000 | 0 | 0
Issuance of common shares - Founders Agreement (in shares) | 0 | 0 | 834,756 |  |  |  |
Stock-based compensation expenses | $ 0 | $ 0 | $ 0 | 0 | 4,960,000 | 0 | 4,960,000
Stock-based compensation expenses (in shares) | 0 | 0 | 496,552 |  |  |  |
Exercise of warrants | $ 0 | $ 0 | $ 0 | 0 | 181,000 | 0 | 181,000
Exercise of warrants (in shares) | 0 | 0 | 42,620 |  |  |  |
Net loss | $ 0 | $ 0 | $ 0 | 0 | 0 | (30,662,000) | (30,662,000)
Balances at Dec. 31, 2018 | $ 0 | $ 0 | $ 3,000 | 2,085,000 | 113,378,000 | (79,070,000) | 36,396,000
Balances (in shares) at Dec. 31, 2018 | 250,000 | 1,000,000 | 26,610,183 |  |  |  |
Common stock issuable - Founders Agreement | $ 0 | $ 0 | $ 0 | 4,923,000 | 0 | 0 | 4,923,000
Issuance of common shares - Founders Agreement | $ 0 | $ 0 | $ 0 | (2,085,000) | 2,085,000 | 0 | 0
Issuance of common shares - Founders Agreement (in shares) | 0 | 0 | 709,314 |  |  |  |
Issuance of common shares - Equity fee on Horizon Notes to Fortress Biotech | $ 0 | $ 0 | $ 0 | 0 | 375,000 | 0 | 375,000
Issuance of common shares - Equity fee on Horizon Notes to Fortress Biotech (in shares) | 0 | 0 | 108,069 |  |  |  |
Issuance of warrants - Horizon Notes | $ 0 | $ 0 | $ 0 | 0 | 888,000 | 0 | 888,000
Issuance of warrants - Horizon Notes (in shares) | 0 | 0 | 0 |  |  |  |
Conversion of Class A common shares to common shares | $ 0 | $ 0 | $ 0 | 0 | 0 | 0 | 0
Conversion of Class A common shares to common shares (in shares) | 0 | (154,615) | 154,615 |  |  |  |
Issuance of common shares, net of offering costs - At-the-Market Offering | $ 0 | $ 0 | $ 0 | 0 | 21,972,000 | 0 | 21,972,000
Issuance of common shares, net of offering costs - At-the-Market Offering (in Shares) | 0 | 0 | 3,506,222 |  |  |  |
Issuance of common shares - Equity fee on At-the-Market Offering | $ 0 | $ 0 | $ 0 | 0 | 495,000 | 0 | 495,000
Issuance of common shares - Equity fee on At-the-Market Offering (in shares) | 0 | 0 | 87,656 |  |  |  |
Issuance of common shares, net of offering costs - Public Offering | $ 0 | $ 0 | $ 1,000 | 0 | 29,536,000 | 0 | 29,537,000
Issuance of common shares, net of offering costs - Public Offering (in shares) | 0 | 0 | 7,906,250 |  |  |  |
Issuance of common shares - Equity fee on Public Offering | $ 0 | $ 0 | $ 0 | 0 | 791,000 | 0 | 791,000
Issuance of common shares - Equity fee on Public Offering (in shares) | 0 | 0 | 197,656 |  |  |  |
Stock-based compensation expenses | $ 0 | $ 0 | $ 0 | 0 | 2,664,000 | 0 | 2,664,000
Stock-based compensation expenses (in shares) | 0 | 0 | 30,341 |  |  |  |
Exercise of warrants | $ 0 | $ 0 | $ 0 | 0 | 0 | 0 | 0
Exercise of warrants (in shares) | 0 | 0 | 93,213 |  |  |  |
Net loss | $ 0 | $ 0 | $ 0 | 0 | 0 | (46,389,000) | (46,389,000)
Balances at Dec. 31, 2019 | $ 0 | $ 0 | $ 4,000 | $ 4,923,000 | $ 172,184,000 | $ (125,459,000) | $ 51,652,000
Balances (in shares) at Dec. 31, 2019 | 250,000 | 845,385 | 39,403,519 |  |  |  |

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