Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 17,515	$ 29,268
Inventory	0	482
Prepaid expenses and other current assets	513	1,244
Total current assets	18,028	30,994
Property and equipment, net	1,489	1,582
Intangible assets, net of accumulated amortization of $0 and $2,204, respectively	0	4,136
Other assets	65	0
Total assets	19,582	36,712
Current liabilities:
Accounts payable	440	499
Related party payable	942	10,720
Accrued expenses	1,551	1,779
Deferred revenue	0	457
Warrant liability, current	54	1,910
Total current liabilities	2,987	15,365
Convertible promissory notes, net of debt discount of $18,088 and $0, respectively (see Note 7)	0	0
Accrued interest payable	228	0
Warrant liability, long term	5,980	6,365
Derivative liability	1,735	0
Deferred rent	791	779
Total liabilities	11,721	22,509
Commitments and contingencies (Note 16)
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares outstanding	0	0
Common stock, $0.001 par value; 150,000,000 shares authorized, 44,058,626 shares issued and outstanding as of December 31, 2016; 100,000,000 shares authorized, 43,898,785 shares issued and outstanding as of December 31, 2015	44	44
Additional paid-in capital	170,380	161,330
Accumulated deficit	(162,563)	(147,171)
Total stockholders’ equity	7,861	14,203
Total liabilities and stockholders’ equity	$ 19,582	$ 36,712