Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 5,718,504	$ 14,991,488
Investment securities – available for sale	37,156,381	8,037,620
Accrued interest receivable on investment securities	212,048	65,925
Deposits on investigator grants	111,635	246,352
Vendor reimbursements receivable	161,764	116,872
Other current assets	401,787	190,727
	43,762,119	23,648,984
Property and equipment (at cost, less accumulated depreciation of $1,264,190 and $924,961, respectively),	832,886	1,114,621
Other assets:
Deferred financing fees	844,249	306,495
Security deposit on letter of credit	200,000	250,000
Other assets	31,318	38,818
	1,075,567	595,313
Total assets	45,670,572	25,358,918
Current liabilities:
Accounts payable ─ trade	1,452,436	2,339,768
Other accrued liabilities	2,707,653	1,254,979
Notes payable - current portion	10,891	1,410,455
Deferred revenue – current portion	500,000
Total current liabilities	4,670,980	5,005,202
Common stock warrant liability	3,026	4,283,932
Note payable – non-current portion	5,000,000	3,661,147
Deferred revenue – non-current portion	4,000,000
Other liabilities – noncurrent	472,731	446,779
Total liabilities	14,146,737	13,397,060
Stockholders’ equity:
Common stock - $0.01 par value (75,000,000 shares authorized; 13,737,970 and 8,437,267 shares issued at December 31, 2013 and 2012 and 13,604,975 and 8,289,507 shares outstanding at December 31, 2013 and 2012, respectively)	137,380	84,373
Additional paid-in capital	203,139,142	170,957,891
Accumulated other comprehensive loss	(44,166)	(126,607)
Accumulated deficit	(169,287,157)	(156,263,288)
	33,945,199	14,652,369
Treasury stock, at cost (132,995 and 147,760 shares at December 31, 2013 and 2012, respectively)	(2,421,364)	(2,690,511)
Total stockholders’ equity	31,523,835	11,961,858
Total liabilities and stockholders’ equity	$ 45,670,572	$ 25,358,918