Condensed Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating activities:
Net loss	$ (1,880)	$ (1,891)
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of warrants		(1)
Depreciation	3	7
Amortization of license agreement	24	25
Stock-based compensation	173	136
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(146)	210
Accounts payable and accrued expenses	(68)	(783)
Net cash used in operating activities	(1,894)	(2,297)
Financing activities:
Proceeds from issuance of common stock, net of issuance costs	1,510	471
Net cash provided by financing activities	1,510	471
Decrease in cash and cash equivalents	(384)	(1,826)
Cash at beginning of period	4,946	9,972
Cash at end of period	$ 4,562	$ 8,146