CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 9,630	$ 7,015
Investments, at fair value		1,661
Accounts receivable, net	49	166
Prepaid expenses and other	519	245
Total current assets	10,198	9,087
Property and equipment, net	231	279
Other assets	97	97
Total assets	10,526	9,463
Current liabilities:
Accounts payable	889	1,096
Accrued expenses and other	519	598
Total current liabilities	1,408	1,694
Warrant liabilities	1,949
Other liabilities	82	89
Total liabilities	3,439	1,783
Stockholders' equity:
Preferred stock, $0.001 par value, 5,000 shares authorized; none issued and outstanding in at June 30, 2016 and December 31, 2015	0	0
Common stock, $0.001 par value; 55,000 shares authorized; 22,736 and 17,264 shares issued and outstanding at June 30, 2016 and December 31, 2015, respectively	23	17
Additional paid-in capital	294,959	292,508
Accumulated other comprehensive loss		(5)
Accumulated deficit	(287,895)	(284,840)
Total stockholders' equity	7,087	7,680
Total liabilities and stockholders' equity	$ 10,526	$ 9,463