| Dec'19 | Dec'18 | Dec'17 | Dec'16 | Dec'15 | Dec'14 | |
|---|---|---|---|---|---|---|
Operating activities | ||||||
Net loss | ||||||
-26,293 | -25,870 | -27,364 | -36,060 | -32,630 | - | |
Net loss | ||||||
- | - | - | - | - | -21,884 | |
Reconciliation of net loss to net cash used in operating activities: | ||||||
Depreciation and amortization | ||||||
26 | 119 | 304 | 395 | 202 | 248 | |
Stock-based compensation expense | ||||||
1,512 | 1,771 | 2,007 | 2,160 | 1,658 | 897 | |
Accretion of discount/premium on investment securities | ||||||
-5 | 6 | -26 | -148 | - | - | |
Non-cash interest expense | ||||||
- | 37 | 155 | 277 | 293 | 74 | |
Gain on disposal of property and equipment | ||||||
-18 | 297 | 30 | 52 | - | - | |
Services received in non-monetary exchange | ||||||
33 | 19 | - | - | - | - | |
Changes in assets and liabilities: | ||||||
Prepaid expenses and other current assets | ||||||
1,289 | 177 | 93 | 229 | 450 | 208 | |
Other assets | ||||||
- | 85 | - | - | -2 | - | |
Right-of-use asset-operating | ||||||
-96 | - | - | - | - | - | |
Accounts payable | ||||||
-211 | 662 | -632 | 77 | 196 | 481 | |
Accrued expenses | ||||||
-205 | 396 | -1,215 | 418 | 954 | 8 | |
Deferred rent | ||||||
- | - | 6 | 8 | -18 | -28 | |
Other liabilities | ||||||
-69 | -34 | - | - | - | - | |
Net cash used in operating activities | ||||||
-26,569 | -23,465 | -26,836 | -32,858 | -29,793 | - | |
Investing activities | ||||||
Purchases of short-term investments | ||||||
155,197 | 70,364 | - | - | - | - | |
Sales and maturities of short-term investments | ||||||
151,127 | 48,090 | 14,910 | - | - | - | |
Net cash used in operating activities | ||||||
- | - | - | - | - | -20,412 | |
Purchases of available-for-sale securities | ||||||
- | - | - | 45,539 | - | 4,976 | |
Sales and maturities of available-for-sale securities | ||||||
- | - | - | 30,456 | - | 4,976 | |
Purchases of property and equipment | ||||||
12 | - | 57 | 459 | 421 | 228 | |
Proceeds from sale of property and equipment | ||||||
- | 369 | 30 | 52 | - | - | |
Net cash used in investing activities | ||||||
-4,082 | -21,905 | 14,883 | -15,490 | -421 | - | |
Financing activities | ||||||
Net cash provided by (used in) investing activities | ||||||
- | - | - | - | - | -228 | |
Proceeds from public offerings, net of issuance costs | ||||||
18,505 | 38,886 | - | - | 61,744 | - | |
Proceeds from issuance of preferred stock, net of issuance costs | ||||||
- | - | - | - | 12,331 | - | |
Proceeds from public offering, net of issuance costs | ||||||
- | - | - | 10,603 | - | - | |
Proceeds from at-the-market offering, net of issuance costs | ||||||
7,061 | 8,253 | 8,036 | 1,391 | - | - | |
Proceeds from exercise of common stock options and warrants | ||||||
- | - | 23 | 503 | 91 | 118 | |
Proceeds from exercise of common stock options and warrants | ||||||
54 | 4 | - | - | - | - | |
Proceeds from borrowing | ||||||
- | - | - | - | 5,000 | 5,000 | |
Payments on borrowing | ||||||
- | 2,848 | 3,333 | 3,333 | 833 | - | |
Debt issuance costs | ||||||
- | - | - | - | 7 | 284 | |
Net cash provided by financing activities | ||||||
25,620 | 44,295 | 4,726 | 9,164 | 78,326 | - | |
Net increase (decrease) in cash, cash equivalents and restricted cash | ||||||
-5,031 | -1,075 | -7,227 | - | - | - | |
Net cash provided by (used in) financing activities | ||||||
- | - | - | - | - | 4,834 | |
Net (decrease) increase in cash and cash equivalents | ||||||
- | - | - | -39,184 | 48,112 | -15,806 | |
Supplemental disclosure of cash flow information | ||||||
Cash paid for interest | ||||||
- | 79 | 327 | 582 | 684 | - | |
Non-cash investing activities: | ||||||
Fixed asset purchases included in accounts payable | ||||||
- | 18 | - | - | - | - | |
Cash paid for interest | ||||||
- | - | - | - | - | 100 | |
Non-cash financing activities | ||||||
At-the-market issuance costs included in current liabilities | ||||||
65 | 110 | - | - | - | - | |
Warrants for the purchase of series B preferred stock issued in conjunction with credit facility | ||||||
- | - | - | - | 107 | 110 | |
Public offering issuance costs included in accounts payable | ||||||
- | - | - | - | -492 | 492 | |
Reclassification of deferred IPO costs from non-current assets to additional paid-in capital | ||||||
- | - | - | - | 1,787 | - | |
Reclassification of warrant liability to additional paid-in capital | ||||||
- | - | - | - | 206 | - | |