Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 5,525,094	$ 5,856,242
Contracts and grants receivable	794,767us-gaap_GrantsReceivableCurrent	867,086us-gaap_GrantsReceivableCurrent
Taxes receivable		750,356us-gaap_IncomeTaxesReceivable
Prepaid expenses	172,928us-gaap_PrepaidExpenseCurrent	135,391us-gaap_PrepaidExpenseCurrent
Total current assets	6,492,789us-gaap_AssetsCurrent	7,609,075us-gaap_AssetsCurrent
Office furniture and equipment, net	51,510us-gaap_PropertyPlantAndEquipmentNet	23,868us-gaap_PropertyPlantAndEquipmentNet
Intangible assets, net	409,949	632,512
Total assets	6,954,248us-gaap_Assets	8,265,455us-gaap_Assets
Current liabilities:
Accounts payable	3,003,545us-gaap_AccountsPayableCurrent	1,520,290us-gaap_AccountsPayableCurrent
Warrant liability	3,789,562us-gaap_DerivativeLiabilitiesCurrent	8,281,247us-gaap_DerivativeLiabilitiesCurrent
Accrued compensation	315,030	233,739
Total current liabilities	7,108,137us-gaap_LiabilitiesCurrent	10,035,276us-gaap_LiabilitiesCurrent
Commitments and contingencies
Shareholders' deficiency:
Preferred stock; 350,000 shares authorized; none issued or outstanding
Common stock, $.001 par value; 50,000,000 shares authorized in 2014 and 2013, respectively; 23,936,568 shares and 19,626,439 shares issued and outstanding in 2014 and 2013, respectively	23,937us-gaap_CommonStockValue	19,626us-gaap_CommonStockValue
Additional paid-in capital	138,868,523us-gaap_AdditionalPaidInCapital	130,549,930us-gaap_AdditionalPaidInCapital
Accumulated deficit	(139,046,349)	(132,339,377)
Total shareholders' deficiency	(153,889)us-gaap_StockholdersEquity	(1,769,821)us-gaap_StockholdersEquity
Total liabilities and shareholders' deficiency	$ 6,954,248	$ 8,265,455

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(a))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682