Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current Assets:
Cash and cash equivalents	$ 26,370	$ 26,892
Inventory	0	195
Prepaid expenses and other current assets	621	719
Total Current Assets	26,991	27,806
Property and equipment, net	1,660	1,737
Restricted cash	400	400
Other Assets	0	0
Total Assets	29,162	29,943
Current Liabilities:
Accounts payable	1,825	1,166
Accrued expenses	4,974	4,159
Common stock warrant liability	6,143	6,305
Equipment loans and capitalized leases, current portion	70	69
Total Current Liabilities	13,012	11,699
Long-term debt, net of discount of $3,917 in 2013 and $0 in 2012	6,083	0
Equipment loans and capitalized leases, non-current portion	129	148
Other liabilities	481	443
Total Liabilities	19,705	12,290
Stockholders' Equity:
Preferred stock, $0.001 par value; 5,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value; 100,000,000 shares authorized; 43,785,629 and 43,673,636 shares issued, 43,764,737 and 43,652,744 shares outstanding at March 31, 2013 and December 31, 2012, respectively	44	44
Additional paid-in capital	459,838	455,398
Accumulated deficit	(447,371)	(434,735)
Treasury stock (at cost); 20,892	(3,054)	(3,054)
Total Stockholders' Equity	9,457	17,653
Total Liabilities & Stockholders' Equity	$ 29,162	$ 29,943