Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 91,316	$ 23,735
Available-for-sale securities	82,126	89,917
Accounts receivable, net	367	794
Inventory	1,704	0
Prepaid expenses and other current assets	3,662	2,541
Total current assets	179,175	116,987
Property and equipment, net	3,132	3,156
Available-for-sale securities, non-current	2,991	22,292
Other assets	878	38
Total assets	186,176	142,473
Current liabilities
Accounts payable	3,878	3,589
Accrued liabilities	12,385	5,867
Other current liabilities	344	287
Total current liabilities	16,607	9,743
Long-term debt	102,647	0
Other non-current liabilities	796	547
Total liabilities	120,050	10,290
Commitments and Contingencies (Note 8)
Stockholders’ equity
Preferred stock, $0.001 par value — 5,000,000 shares authorized, and zero shares issued and outstanding at December 31, 2017 and December 31, 2016	0	0
Common stock, $0.001 par value — 100,000,000 shares authorized, 23,320,551 and 22,013,644 shares issued and outstanding at December 31, 2017 and December 31, 2016, respectively	28	27
Additional paid-in capital	277,964	254,558
Accumulated other comprehensive loss	(167)	(193)
Accumulated deficit	(211,699)	(122,209)
Total stockholders’ equity	66,126	132,183
Total liabilities and stockholders’ equity	$ 186,176	$ 142,473