| Mar'20 | Dec'19 | Sep'19 | Jun'19 | Mar'19 | Dec'18 | Sep'18 | Jun'18 | Mar'18 | Dec'17 | Sep'17 | Jun'17 | Mar'17 | Dec'16 | Sep'16 | Jun'16 | Mar'16 | Dec'15 | Sep'15 | Jun'15 | Mar'15 | Dec'14 | Sep'14 | Jun'14 | Mar'14 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Operating activities | ||||||||||||||||||||||||
Net loss | ||||||||||||||||||||||||
-51,470 | -57,891 | -57,072 | -55,395 | -50,844 | -48,273 | -43,624 | -39,999 | -36,862 | -33,281 | -32,351 | -32,256 | -32,186 | -31,809 | -32,362 | -31,676 | -13,215 | -12,769 | -11,281 | -10,731 | -13,128 | -11,121 | 0 | 0 | 0 |
Adjustments to reconcile net loss to net cash used in operating activities: | ||||||||||||||||||||||||
Depreciation | ||||||||||||||||||||||||
276 | 279 | 279 | 278 | 276 | 275 | 276 | 277 | 277 | 263 | 244 | 220 | 197 | 190 | 188 | 194 | 194 | 191 | 186 | 175 | 168 | 158 | 0 | 0 | 0 |
Non-cash lease expense | ||||||||||||||||||||||||
634 | 620 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Stock-based compensation expense | ||||||||||||||||||||||||
6,654 | 6,215 | 5,638 | 5,222 | 4,853 | 4,587 | 4,401 | 4,193 | 4,033 | 3,760 | 3,522 | 3,299 | 3,080 | 2,964 | 2,883 | 2,777 | 2,463 | 2,323 | 2,161 | 1,970 | 1,930 | 1,635 | 0 | 0 | 0 |
Changes in assets and liabilities: | ||||||||||||||||||||||||
Prepaid expenses and other current assets | ||||||||||||||||||||||||
-770 | 2,059 | 1,389 | -1,097 | -563 | -943 | 1,589 | 2,981 | 2,780 | 2,816 | -223 | -946 | 13 | 36 | 521 | 914 | -93 | -474 | 130 | -346 | 58 | -1,656 | 0 | 0 | 0 |
Accounts payable | ||||||||||||||||||||||||
1,303 | -1,227 | 748 | -212 | -2,022 | 16 | -992 | 2,644 | 3,331 | 1,061 | 384 | -806 | -1,069 | 1,000 | 613 | 284 | 397 | -309 | 49 | 624 | -623 | -270 | 0 | 0 | 0 |
Accrued expenses | ||||||||||||||||||||||||
951 | 2,709 | 2,562 | 3,133 | 1,138 | 551 | 832 | -981 | 585 | 724 | 743 | 130 | -30 | -2,504 | -2,156 | -1,134 | 1,108 | 1,693 | 2,202 | 2,637 | 2,114 | 4,459 | 0 | 0 | 0 |
Noncurrent accrued expenses | ||||||||||||||||||||||||
0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Operating lease liabilities | ||||||||||||||||||||||||
-650 | -629 | 0 | 0 | 0 | - | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Deferred rent | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | - | -37 | -121 | -67 | 574 | 578 | 736 | 814 | 182 | 146 | 0 | 0 | 0 | - | - | 0 | 0 |
Net cash used in operating activities | ||||||||||||||||||||||||
-41,136 | -51,984 | -49,171 | -45,806 | -47,469 | -43,331 | -41,720 | -37,865 | -30,915 | -29,768 | -27,354 | -28,596 | -29,563 | -29,731 | -30,734 | -9,698 | -8,766 | -8,241 | -7,438 | -25,756 | -10,399 | -4,281 | 0 | 0 | 0 |
Investing activities | ||||||||||||||||||||||||
Purchases of property and equipment | ||||||||||||||||||||||||
113 | 144 | 189 | 197 | 148 | 125 | 102 | 108 | 247 | 294 | 698 | 891 | 749 | 704 | 268 | 101 | 283 | 268 | 280 | 323 | 201 | 212 | 0 | 0 | 0 |
Net cash used in investing activities | ||||||||||||||||||||||||
-113 | -144 | -189 | -197 | -148 | -125 | -102 | -108 | -247 | -294 | -698 | -891 | -749 | -704 | -268 | -101 | -283 | -268 | -280 | -323 | -201 | -212 | 0 | 0 | 0 |
Financing activities | ||||||||||||||||||||||||
Proceeds from issuance of common stock, net of issuance costs | ||||||||||||||||||||||||
- | - | - | - | - | 128,425 | 147,728 | 147,591 | 238,538 | 113,572 | 95,417 | 95,417 | 26,031 | 23,601 | 0 | 0 | 0 | - | - | - | - | 57,248 | 0 | 0 | 0 |
Proceeds from exercise of stock options | ||||||||||||||||||||||||
512 | 412 | 419 | 737 | 756 | 1,024 | 1,050 | 669 | 666 | 373 | 225 | 132 | 42 | 72 | 71 | 61 | 74 | 114 | 0 | 0 | 0 | - | - | - | - |
Net cash provided by financing activities | ||||||||||||||||||||||||
512 | 412 | 419 | 737 | 547 | 129,449 | 148,778 | 148,261 | 239,204 | 113,945 | 95,642 | 95,550 | 26,073 | 23,674 | 22,525 | 22,651 | 1,313 | 114 | 116 | 97 | 201 | 57,382 | 0 | 0 | 0 |
Net change in cash and cash equivalents | ||||||||||||||||||||||||
-40,737 | -51,716 | -48,941 | -45,267 | -47,071 | 85,992 | 106,956 | 110,286 | 208,041 | 83,883 | 67,589 | 66,062 | -4,239 | -6,760 | -8,477 | 12,851 | -7,736 | -8,396 | -7,602 | -25,983 | -10,399 | 52,888 | 0 | 0 | 0 |
Non-cash investing and financing activities | ||||||||||||||||||||||||
Property acquisition costs included in accrued expenses | ||||||||||||||||||||||||
- | - | - | - | 0 | - | - | - | - | - | - | - | 0 | - | - | - | - | - | - | 0 | 0 | - | - | - | - |
Issuance costs associated with financing included in accrued expenses | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Issuance costs associated with the at-the-market financing included in accounts payable and accrued expenses | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 | - | - | - | - | - | - | - | - |