| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cash flows from operating activities | ||||||||||||||||||||||||
Net loss | ||||||||||||||||||||||||
-643,572 | -680,238 | -669,973 | -612,933 | -461,690 | -372,882 | -283,916 | -234,717 | -287,940 | -270,120 | -256,599 | -220,676 | -185,222 | -158,987 | -131,648 | -117,887 | -108,167 | -94,495 | -78,294 | -63,727 | -44,892 | -33,811 | 0 | 0 | 0 |
Adjustments to reconcile net loss to net cash used in operating activities: | ||||||||||||||||||||||||
Stock-based compensation expense | ||||||||||||||||||||||||
140,225 | 153,231 | 154,192 | 136,001 | 130,262 | 101,963 | 80,568 | 64,821 | 45,143 | 35,534 | 35,382 | 30,399 | 25,514 | 23,020 | 17,013 | 16,672 | 17,605 | 15,240 | 12,480 | 8,764 | 3,701 | 2,512 | 0 | 0 | 0 |
Non-cash licensing and consulting fees | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 1,211 | 1,211 | 1,211 | 424 | 127 | 0 | 0 | 0 |
Premium on marketable securities | ||||||||||||||||||||||||
3,175 | 3,674 | 2,702 | 2,027 | 950 | 215 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Amortization of discount on marketable securities | ||||||||||||||||||||||||
4,662 | 6,966 | 9,420 | 10,711 | 10,866 | 9,892 | 7,137 | 4,452 | 1,674 | 293 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - |
Depreciation | ||||||||||||||||||||||||
2,600 | 2,300 | 1,900 | 1,527 | 1,253 | 1,100 | 904 | 733 | 617 | 500 | 478 | 425 | 370 | 281 | 231 | 177 | 134 | 115 | 99 | 83 | 62 | 51 | 0 | 0 | 0 |
Changes in operating assets and liabilities: | ||||||||||||||||||||||||
Prepaid expenses and other current assets | ||||||||||||||||||||||||
5,197 | 4,781 | 11,685 | -4,527 | 8,477 | 15,462 | 13,606 | 26,125 | 5,095 | 1,127 | 1,474 | 3,381 | 3,553 | 3,362 | 813 | -1,464 | 1,736 | 681 | 1,541 | 2,499 | 797 | 715 | 0 | 0 | 0 |
Other long-term assets | ||||||||||||||||||||||||
2,316 | 3,793 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Right-of-use operating asset | ||||||||||||||||||||||||
-7,004 | -8,168 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Operating lease liabilities, current | ||||||||||||||||||||||||
0 | - | - | - | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Operating lease liabilities, non-current | ||||||||||||||||||||||||
0 | - | - | - | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Accounts payable | ||||||||||||||||||||||||
-5,583 | -18,783 | -1,041 | 3,641 | 4,914 | 24,544 | -7,284 | 2,172 | 73 | -3,693 | 7,901 | 87 | 3,952 | 7,796 | 1,898 | 771 | 1,448 | 2,590 | 1,255 | 3,586 | 1,255 | 441 | 0 | 0 | 0 |
Accrued expenses and other liabilities | ||||||||||||||||||||||||
6,605 | 33,804 | 28,417 | 18,345 | 14,398 | 10,130 | 12,889 | 14,020 | 6,316 | 19,996 | 20,158 | 14,497 | 12,923 | 13,044 | 10,876 | 7,321 | 6,419 | 5,339 | 3,559 | 3,380 | 4,215 | 4,353 | 0 | 0 | 0 |
Net cash used in operating activities | ||||||||||||||||||||||||
-515,463 | -528,706 | -513,758 | -465,243 | -332,034 | -260,671 | -217,792 | -183,697 | -242,638 | -219,277 | -194,154 | -178,858 | -146,453 | -118,678 | -103,019 | -91,738 | -83,510 | -70,681 | -61,231 | -49,202 | -36,032 | -27,042 | 0 | 0 | 0 |
Proceeds from sales and maturities of marketable securities | ||||||||||||||||||||||||
1,139,204 | 1,171,270 | 1,208,465 | 1,299,949 | 1,200,060 | 974,757 | 770,921 | 414,249 | 292,432 | 261,225 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - |
Purchases of marketable securities | ||||||||||||||||||||||||
796,410 | 1,308,675 | 1,289,101 | 1,589,254 | 1,671,165 | 1,484,358 | 1,423,546 | 1,023,818 | 619,604 | 244,403 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - |
Purchases of property and equipment | ||||||||||||||||||||||||
4,770 | 5,751 | 6,186 | 5,244 | 3,465 | 2,860 | 2,856 | 2,093 | 1,767 | 1,360 | 1,076 | 907 | 1,325 | 1,421 | 939 | 852 | 429 | 198 | 205 | 304 | 235 | 128 | 0 | 0 | 0 |
Net cash provided by (used in) investing activities | ||||||||||||||||||||||||
338,024 | -143,156 | -86,822 | -294,549 | -474,570 | -512,461 | -655,481 | -611,662 | -328,939 | 15,462 | 2,126 | -69,465 | -198,074 | -230,015 | -112,115 | -84,374 | -429 | -198 | -205 | -304 | -235 | -128 | 0 | 0 | 0 |
Cash flows from financing activities | ||||||||||||||||||||||||
Proceeds from stock option exercises and employee stock purchase plan issuances | ||||||||||||||||||||||||
36,329 | 48,850 | 48,312 | 40,988 | 32,032 | 29,108 | 36,454 | 32,063 | 28,176 | 15,972 | 7,676 | 4,405 | 1,657 | 1,406 | 795 | 606 | 885 | 730 | 0 | 0 | 0 | - | - | - | - |
Payment of employee tax obligations related to vesting of restricted stock units | ||||||||||||||||||||||||
- | 2,175 | 2,175 | 692 | 692 | 904 | 0 | 0 | 0 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
Payments of offering costs | ||||||||||||||||||||||||
- | 328 | 328 | 328 | 175 | 340 | 0 | 0 | 0 | - | - | - | - | 599 | 635 | 725 | 1,148 | 584 | 0 | 0 | 0 | - | - | - | - |
Proceeds from public offerings of common stock, net of commissions and underwriting discounts | ||||||||||||||||||||||||
- | 561,277 | 561,277 | 561,277 | 561,277 | 631,494 | 0 | 0 | 0 | - | - | - | - | 330,175 | 0 | 0 | 0 | - | - | - | - | 96,255 | 0 | 0 | 0 |
Net cash provided by financing activities | ||||||||||||||||||||||||
34,588 | 607,624 | 607,086 | 601,245 | 592,442 | 659,358 | 992,550 | 988,159 | 984,377 | 341,818 | 7,676 | 193,580 | 190,832 | 330,982 | 330,335 | 140,881 | 270,457 | 129,866 | 129,586 | 224,613 | 94,004 | 146,870 | 0 | 0 | 0 |
Net increase in cash, cash equivalents and restricted cash | ||||||||||||||||||||||||
-142,851 | -64,238 | 6,506 | -158,547 | -214,162 | -113,774 | 119,277 | 192,800 | 412,800 | 138,003 | -184,352 | -54,743 | -153,695 | -17,711 | 115,201 | -35,231 | 186,518 | 58,987 | 68,150 | 175,107 | 57,737 | 119,700 | 0 | 0 | 0 |
Supplemental disclosure of non-cash operating and investing activities | ||||||||||||||||||||||||
Accretion of redeemable convertible preferred stock to redemption value | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 2,294 | 0 | 0 | 0 |
Purchases of property and equipment included in accounts payable | ||||||||||||||||||||||||
2 | 65 | 43 | 293 | 114 | 51 | 0 | 0 | 0 | - | - | - | 0 | - | - | - | 0 | - | - | - | - | - | - | - | - |
Public offering costs included in accounts payable | ||||||||||||||||||||||||
- | - | - | - | 0 | - | - | - | 0 | - | - | - | - | - | - | - | - | 165 | 0 | 0 | 0 | - | - | - | - |
Deferred public offering costs included in accounts payable or accrued expenses | ||||||||||||||||||||||||
- | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 0 |