Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 62,431	$ 6,178
Prepaid expenses and other current assets	820	1,013
Total current assets	63,251	7,191
Property and equipment, net	400	474
Restricted cash	334	334
Other assets	1,484	347
Total assets	65,469	8,346
Current liabilities:
Accounts payable	3,089	1,887
Accrued expenses and other liabilities	4,263	6,503
Capital lease obligations	23	21
Deferred rent	48	57
Convertible notes, related party		29,770
Total current liabilities	7,423	38,238
Capital lease obligations	17	40
Deferred rent	184	219
Term loan	15,074	14,789
Preferred stock warrant liabilities		2,460
Total liabilities	$ 22,698	$ 55,746
Commitments and contingencies (Note 12)
Convertible preferred stock		$ 61,982
Stockholders’ equity (deficit):
Preferred stock, par value $0.001; 1,000,000 and no shares authorized as of December 31, 2015 and 2014, respectively; no shares issued and outstanding as of December 31, 2015 and 2014
Common stock, par value $0.001; 500,000,000 shares authorized and 18,815,689 shares issued and outstanding as of December 31, 2015; common stock, par value $0.0001; 8,456,867 shares authorized and 403,539 shares issued and outstanding as of December 31, 2014	$ 19
Additional paid-in capital	206,129	$ 4,378
Accumulated other comprehensive income (loss)	0	0
Accumulated deficit	(163,377)	(113,760)
Total stockholders’ equity (deficit)	42,771	(109,382)
Total liabilities, convertible preferred stock and stockholders’ equity (deficit)	$ 65,469	$ 8,346