| Schedule of quarterly financial information |
| | | | | | | | | | | | | | | | | | First Quarter Ended March 31, 2016 | | Second Quarter
Ended
June 30, 2016 | | Third Quarter Ended
September 30, 2016 | | Fourth Quarter Ended December 31, 2016 | Net product revenue | $ | — |
| | $ | 112,685 |
| | $ | 586,134 |
| | $ | 291,099 |
| Other revenue | — |
| | — |
| | 12,940 |
| | 7,805 |
| Total revenue | — |
| | 112,685 |
| | 599,074 |
| | 298,904 |
| Costs and expenses: | |
| | | | | | | Cost of product revenue | 197,020 |
| | 110,931 |
| | 221,090 |
| | 133,706 |
| Research and development | 4,387,079 |
| | 6,094,921 |
| | 5,665,357 |
| | 4,230,804 |
| Selling, general and administrative | 5,111,695 |
| | 5,377,784 |
| | 5,447,847 |
| | 3,918,661 |
| Total costs and expenses | 9,695,794 |
| | 11,583,636 |
| | 11,334,294 |
| | 8,283,171 |
| Loss from operations | (9,695,794 | ) | | (11,470,951 | ) | | (10,735,220 | ) | | (7,984,267 | ) | Interest income, net | 103,333 |
| | 107,818 |
| | 97,726 |
| | 84,232 |
| Net loss | $ | (9,592,461 | ) | | $ | (11,363,133 | ) | | $ | (10,637,494 | ) | | $ | (7,900,035 | ) | Net loss per share attributable to common stockholders — basic and diluted | $ | (0.61 | ) | | $ | (0.71 | ) | | $ | (0.65 | ) | | $ | (0.48 | ) | Weighted-average number of common shares outstanding — basic and diluted | 15,843,532 |
| | 16,105,555 |
| | 16,361,617 |
| | 16,619,596 |
|
| | | | | | | | | | | | | | | | | | First Quarter Ended March 31, 2015 | | Second Quarter
Ended
June 30, 2015 | | Third Quarter Ended September 30, 2015 | | Fourth Quarter Ended December 31, 2015 | Costs and expenses: | |
| | | | | | | Research and development | $ | 2,804,946 |
| | $ | 3,190,178 |
| | $ | 3,445,200 |
| | $ | 3,309,055 |
| Selling, general and administrative | 3,216,212 |
| | 3,904,403 |
| | 4,722,281 |
| | 4,621,383 |
| Total costs and expenses | 6,021,158 |
| | 7,094,581 |
| | 8,167,481 |
| | 7,930,438 |
| Loss from operations | (6,021,158 | ) | | (7,094,581 | ) | | (8,167,481 | ) | | (7,930,438 | ) | Interest income, net | 3,577 |
| | 16,183 |
| | 14,637 |
| | 37,631 |
| Net loss | $ | (6,017,581 | ) | | $ | (7,078,398 | ) | | $ | (8,152,844 | ) | | $ | (7,892,807 | ) | Net loss per share attributable to common stockholders — basic and diluted | $ | (0.59 | ) | | $ | (0.47 | ) | | $ | (0.53 | ) | | $ | (0.51 | ) | Weighted-average number of common shares outstanding — basic and diluted | 10,179,955 |
| | 15,034,764 |
| | 15,290,435 |
| | 15,551,800 |
|
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