| Dec'19 | Dec'18 | Dec'17 | Dec'16 | Dec'15 | Dec'14 | Dec'13 |
|---|---|---|---|---|---|---|
Cash flows from operating activities: | ||||||
Net loss | ||||||
-70,279 | -98,942 | -89,380 | -91,579 | -54,780 | -16,709 | -6,102 |
Adjustments to reconcile net loss to net cash used in operating activities: | ||||||
Stock-based compensation expense | ||||||
8,344 | 16,641 | 17,362 | 16,857 | 9,694 | 2,068 | 209 |
Depreciation and amortization expense | ||||||
7,603 | 7,862 | 7,259 | 4,205 | 728 | 190 | 88 |
Non-cash operating lease cost | ||||||
2,227 | - | - | - | - | - | - |
Accretion of discount on investments | ||||||
172 | 214 | 216 | 386 | - | - | - |
Loss from revaluation of preferred stock warrant liability | ||||||
- | - | - | - | 7 | 1,418 | 8 |
Licensing fees paid in common stock warrant | ||||||
- | - | - | - | - | 317 | - |
Non-cash interest expense | ||||||
281 | - | 3 | - | 367 | 81 | - |
Loss on disposal of property and equipment | ||||||
-103 | - | - | - | - | - | - |
Other non-cash expense | ||||||
- | - | - | - | - | - | 19 |
Changes in operating assets and liabilities: | ||||||
Prepaid expenses and other current assets | ||||||
-3,257 | 2,056 | -31 | 2,598 | 2,470 | 7 | 21 |
Accounts receivable | ||||||
1,785 | - | - | - | - | - | - |
Deferred revenue | ||||||
-17,520 | 13,476 | -11,888 | 108,814 | - | - | - |
Accounts payable | ||||||
-1,460 | -353 | -856 | 3,581 | 2,682 | 810 | 281 |
Operating lease liabilities | ||||||
-4,211 | - | - | - | - | - | - |
Accrued expenses and other liabilities | ||||||
-2,908 | 732 | 2,162 | 5,027 | 2,928 | 1,474 | 197 |
Net cash (used in) operating activities | ||||||
-76,520 | -62,854 | -75,523 | 43,921 | - | - | - |
Cash flows from investing activities: | ||||||
Net cash used in operating activities | ||||||
- | - | - | - | -40,844 | -10,358 | -5,321 |
Purchases of property and equipment | ||||||
1,002 | 1,937 | 4,676 | 21,492 | 4,362 | 1,001 | 174 |
Purchases of investments | ||||||
46,420 | 21,832 | 97,934 | 290,594 | 267,761 | - | - |
Sales and maturities of investments | ||||||
16,904 | 136,087 | 158,312 | 246,494 | 136,390 | - | - |
Net cash (used in) provided by investing activities | ||||||
-30,518 | 112,318 | 55,702 | -65,592 | - | - | - |
Cash flows from financing activities: | ||||||
Proceeds from public offering of common stock, net of commissions, underwriting discounts and offering costs | ||||||
60,527 | - | - | - | 143,015 | - | - |
Proceeds from issuance of note payable | ||||||
25,000 | - | - | - | - | - | - |
Proceeds from at the market equity offering | ||||||
512 | - | - | - | - | - | - |
Payments of debt issuance costs | ||||||
425 | - | - | - | - | - | - |
Proceeds from exercise of stock options | ||||||
145 | 147 | 116 | 2,138 | - | - | - |
Proceeds from issuance of common stock and restricted common stock | ||||||
176 | 61 | - | - | - | - | - |
Changes in restricted cash | ||||||
- | - | - | - | 1,400 | 102 | 10 |
Net cash provided by investing activities | ||||||
- | - | - | - | -137,133 | -1,103 | -184 |
Proceeds from issuance of convertible preferred stock, net of issuance costs | ||||||
- | - | - | - | -24 | 123,203 | - |
Proceeds from issuance of notes payable and preferred stock warrant, net of issuance costs | ||||||
- | - | - | - | - | 2,000 | 944 |
Proceeds from exercise of stock options and common stock warrants | ||||||
- | - | - | - | 262 | 5 | - |
Payments for repurchase of common stock for employee tax withholdings | ||||||
- | 197 | 33 | - | - | - | - |
Issuance of common stock under ESPP plan | ||||||
296 | 257 | - | - | - | - | - |
Net cash provided by financing activities | ||||||
86,231 | 268 | 83 | 2,138 | - | - | - |
Net increase (decrease) in cash and cash equivalents | ||||||
-20,807 | 49,732 | -19,738 | -19,533 | - | - | - |
Proceeds from issuance of common stock and restricted common stock | ||||||
- | - | - | - | - | 5 | - |
Repayment of notes payable | ||||||
- | - | - | - | 2,600 | 400 | - |
Payments of initial public offering costs | ||||||
- | - | - | - | 2,928 | 821 | - |
Net cash (used in) provided by financing activities | ||||||
- | - | - | - | 137,725 | 123,992 | 944 |
Net increase (decrease) in cash and cash equivalents | ||||||
- | - | - | - | -40,252 | 112,531 | -4,561 |
Supplemental disclosure of cash flow information: | ||||||
Cash paid for interest | ||||||
221 | - | 1 | 109 | - | - | - |
Cash paid for interest | ||||||
- | - | - | - | 163 | 122 | 20 |
Supplemental disclosure of non-cash investing and financing activities: | ||||||
Accretion of convertible preferred stock to redemption value | ||||||
- | - | - | - | - | 1,291 | 875 |
Issuance of preferred stock warrant in connection with notes payable | ||||||
- | - | - | - | - | - | 156 |
Deferred offering costs included in accounts payable | ||||||
- | - | - | - | - | 863 | - |
Property and equipment purchases included in accounts payable and accrued expenses | ||||||
62 | 157 | 877 | 1,650 | 2,953 | 101 | - |
Reduction of operating lease assets and operating lease liabilities from operating lease modifications or reassessments | ||||||
154 | - | - | - | - | - | - |