Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 15,419	$ 18,613
Short-term investments	54,746	66,897
Accounts receivable	710	668
Prepaids and other current assets	3,748	4,059
Total current assets	74,623	90,237
Property and equipment, net	504	541
Other assets	59	68
Restricted cash	294	294
Total assets	75,480	91,140
Current liabilities:
Accounts payable	1,451	2,021
Accrued expenses	4,015	4,328
Deferred revenue	2,417	2,204
Deferred rent	205	201
Total current liabilities	8,088	8,754
Deferred revenue, net of current portion	228	752
Deferred rent, net of current portion	35	87
Derivative liability	37	91
Total liabilities	8,388	9,684
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized as of March 31, 2017 and December 31, 2016, respectively; no shares issued and outstanding as of March 31, 2017 and December 31, 2016
Common stock, $0.001 par value; 125,000,000 shares authorized as of March 31, 2017 and December 31, 2016, respectively; 25,024,042 and 25,000,734 shares issued and outstanding as of March 31, 2017 and December 31, 2016, respectively	26	26
Additional paid-in capital	239,650	238,902
Accumulated other comprehensive loss	(38)	(22)
Accumulated deficit	(172,546)	(157,450)
Total stockholders’ equity	67,092	81,456
Total liabilities and stockholders’ equity	$ 75,480	$ 91,140