| Dec'18 | Dec'17 | Dec'16 | Dec'15 | Dec'14 | Dec'13 | Dec'12 |
|---|---|---|---|---|---|---|
Operating activities | ||||||
Net loss | ||||||
-54,758 | -51,862 | -53,530 | -39,445 | -34,151 | -15,975 | -10,840 |
Adjustments to reconcile net loss to net cash used in operating activities: | ||||||
Depreciation and amortization | ||||||
346 | 351 | 304 | 243 | 238 | 407 | 548 |
Amortization of premium/discount on investments | ||||||
561 | 26 | -126 | 0 | 0 | - | - |
Impairment of inventory | ||||||
1,200 | 0 | 0 | - | - | - | - |
Stock-based compensation | ||||||
7,276 | 8,633 | 9,283 | 6,297 | 1,344 | 255 | 244 |
Revaluation of convertible preferred stock warrant liability | ||||||
- | - | - | - | 4,277 | 955 | 0 |
Other | ||||||
- | - | - | - | - | -94 | -23 |
Changes in operating assets and liabilities: | ||||||
Accounts receivable | ||||||
58 | 130 | -455 | -998 | 1,883 | -426 | 452 |
Inventory | ||||||
652 | 77 | 594 | -12 | 8 | -109 | 252 |
Prepaid expenses | ||||||
184 | -975 | 892 | 1,021 | 454 | -8 | -152 |
Restricted cash | ||||||
- | - | - | 0 | - | - | - |
Other assets | ||||||
-1,348 | -22 | 3,059 | 0 | 0 | - | - |
Security deposit | ||||||
- | - | - | 0 | - | - | - |
Accounts payable | ||||||
-856 | -2,225 | 1,485 | -3,829 | 6,037 | -213 | 504 |
Accrued liabilities | ||||||
1,181 | 1,203 | 976 | -519 | 3,424 | -453 | 623 |
Accrued litigation-related settlement | ||||||
-6,000 | -1,250 | 7,250 | 0 | 0 | - | - |
Deferred revenue | ||||||
0 | -2,545 | 2,496 | - | - | - | - |
Deferred revenue | ||||||
- | - | - | -510 | - | - | - |
Deferred rent and other noncurrent liabilities | ||||||
8 | 72 | -40 | -27 | 507 | 89 | -128 |
Net cash used in operating activities | ||||||
-51,666 | -46,859 | -35,740 | -37,801 | -20,669 | -14,298 | -9,578 |
Investing activities | ||||||
Purchases of property and equipment | ||||||
390 | 428 | 133 | 427 | 344 | 175 | 294 |
Purchases of short-term investments | ||||||
34,685 | 71,611 | 102,288 | - | - | - | - |
Maturities of short-term investments | ||||||
86,000 | 65,000 | 40,000 | 0 | 0 | - | - |
Purchases of short-term investments | ||||||
- | - | - | 0 | 0 | - | - |
Proceeds from the sale of property and equipment | ||||||
- | - | - | - | - | 43 | 0 |
Net cash provided by (used in) investing activities | ||||||
50,925 | -7,039 | -62,421 | -427 | -344 | -132 | -294 |
Financing activities | ||||||
Issuance of common stock in public offering, net of offering costs | ||||||
0 | 86,624 | 30,310 | 75,359 | 57,807 | 0 | 0 |
Proceeds from exercise of preferred stock warrants | ||||||
- | - | - | - | 8,150 | 0 | 0 |
Proceeds from issuances of common stock under stock-based compensation plans | ||||||
228 | 714 | 144 | 436 | 23 | 6 | - |
Proceeds from sale of convertible preferred stock, net of cash paid for issuance costs | ||||||
- | - | - | - | - | 29,668 | 10,615 |
Proceeds from sale of convertible preferred stock warrants | ||||||
- | - | - | - | - | 2,381 | 0 |
Proceeds from exercise of stock options | ||||||
- | - | - | - | - | - | 11 |
Net cash provided by financing activities | ||||||
228 | 87,338 | 30,454 | 75,795 | 65,980 | 32,055 | 10,626 |
Net (decrease) increase in cash and cash equivalents | ||||||
-513 | 33,440 | -67,707 | - | - | - | - |
Supplemental cash flow information | ||||||
Unpaid stock offering costs | ||||||
0 | 48 | 0 | 0 | - | - | - |
Net (decrease) increase in cash and cash equivalents | ||||||
- | - | - | 37,567 | 44,967 | 17,625 | 754 |