Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 26,091	$ 44,711
Inventory, net	0	27
Prepaid expenses and other current assets	571	821
Total current assets	26,662	45,559
Property and equipment, net	1,245	1,637
Restricted cash	225	225
Other assets	68	78
Total assets	28,200	47,499
Current Liabilities:
Accounts payable	2,314	350
Accrued expenses	6,613	6,116
Deferred revenue	0	43
Common stock warrant liability	820	1,258
Equipment loans, current portion	21	62
Total current liabilities	9,768	7,829
Long-term debt, $30,000 net of discount of $8,549 at June 30, 2015 and $9,698 at December 31, 2014	21,451	20,302
Other liabilities	59	169
Total liabilities	31,278	28,300
Stockholders' (Deficit) / Equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value; 250,000,000 shares authorized; 85,937,481 and 85,607,806 shares issued at June 30, 2015 and December 31, 2014, respectively; 85,916,589 and 85,586,914 shares outstanding at June 30, 2015 and December 31, 2014, respectively	86	86
Additional paid-in capital	547,403	546,175
Accumulated deficit	(547,513)	(524,008)
Treasury stock (at cost); 20,892 shares	(3,054)	(3,054)
Total stockholders' (deficit) / equity	(3,078)	19,199
Total liabilities & stockholders' (deficit) / equity	$ 28,200	$ 47,499