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CONSOLIDATED CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (UNAUDITED) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Development revenues: |  |  |  |
Government contracts and other |  | $ 4,771 | $ 303 | $ 5,810
Operating expenses: |  |  |  |
Research and development | $ 336 | 921 | 1,604 | 3,636
Sales and marketing | 104 | 94 | 319 | 305
General and administrative | 956 | 1,076 | 3,788 | 3,313
Total operating expenses | 1,396 | 2,091 | 6,492 | 7,254
Operating income (loss) | (1,396) | 2,680 | (6,189) | (1,444)
Other income (expense): |  |  |  |
Interest income | 2 | 6 | 47 | 20
Interest expense | (253) | (366) | (854) | (1,477)
Change in fair value of warrants | (81) | (561) | 2,342 | (69)
Warrant issuance cost |  | (1,233) |  | (1,233)
Total other income (expense) | (332) | (2,154) | 1,535 | (2,759)
Income (Loss) from continuing operations | (1,728) | 526 | (4,654) | (4,203)
Loss from discontinued operations |  |  |  | (7,568)
Net income (loss) | (1,728) | 526 | (4,654) | (11,771)
Income (Loss) from continuing operations | (1,728) | 526 | (4,654) | (4,203)
Beneficial conversion feature for convertible preferred stock |  | (554) |  | (554)
Net loss allocable to common stockholders - continuing operations | $ (1,728) | $ (28) | $ (4,654) | (4,757)
Net loss allocable to common stockholders - discontinued operations |  |  |  | $ (7,568)
Basic and diluted net loss per share attributable to common stockholders - continuing operations | $ (0.39) | $ (0.03) | $ (1.13) | $ (8.78)
Basic and diluted net loss per share attributable to common stockholders - discontinued operations |  |  |  | (13.97)
Net loss per share, basic and diluted | $ (0.39) | $ (0.03) | $ (1.13) | $ (22.75)
Basic and diluted weighted average shares used in calculating net loss per share attributable to common stockholders | 4,402,221 | 826,548 | 4,113,928 | 541,777
In Process Research and Development [Member] | Nano Tx Therapeutics [Member] |  |  |  |
Operating expenses: |  |  |  |
Research and development |  |  | $ 781 |

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