Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 12,906	$ 5,117
Restricted cash	50	50
Short-term investments		5,500
Prepaid expenses	150	311
Total current assets	13,106	10,978
Property and equipment, net of accumulated depreciation of $831 and $778, in 2016 and 2015, respectively	114	163
Notes receivable	150
Other assets	27	18
Total assets	13,397	11,159
Current liabilities:
Accounts payable	917	1,163
Accrued expenses	1,625	1,106
Total current liabilities	2,542	2,269
Commitments and contingencies (Note 8)
Stockholders' equity:
Preferred stock, $0.0001 par value, 10,000,000 shares authorized at December 31, 2016 and 2015
Common stock, $0.0001 par value, 100,000,000 shares authorized; 13,003,179 and 6,534,846 shares issued and outstanding at December 31, 2016 and December 31, 2015, respectively	1	1
Additional paid-in capital	73,428	65,994
Accumulated deficit	(66,099)	(57,105)
Total stockholders' equity	10,855	8,890
Total liabilities and stockholders' equity	13,397	$ 11,159
Series B Convertible Preferred Stock [Member]
Stockholders' equity:
Series B convertible preferred stock, $0.0001 par value; 8,100 shares authorized; 5,737 shares issued and outstanding at December 31, 2016 (at fair value)	3,525
Total stockholders' equity	$ 3,525