Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
ASSETS
Cash and cash equivalents	$ 175,985	$ 259,701
Grant funds and other receivables	160,277	121,814
Prepaid expenses and other current assets	111,647	238,189
Total current assets	447,909	619,704
Property and equipment, net (Note 5)	13,725	11,350
Deposits	11,010	11,010
Total assets	472,644	642,064
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIENCY)
Accounts payable	253,166	125,859
Accrued expenses (Note 6)	1,378,710	1,238,552
Current portion of notes payable (Note 7)	12,500	260,420
Total current liabilities	1,644,376	1,624,831
Note payable, net of current portion (Note 7)	35,417	39,580
Total liabilities	1,679,793	1,664,411
Commitments (Note 8)
Stockholders’ equity (deficiency):
Common stock, $.001 par value: authorized shares – 600,000,000 issued and outstanding shares – 556,489 and 437,807 at March 31, 2019 and December 31, 2018, respectively	556	438
Additional paid-in capital	37,898,525	37,482,766
Accumulated deficit	(41,178,338)	(40,476,884)
Total stockholders’ equity (deficiency)	(1,207,149)	(1,022,347)
Total liabilities and stockholders’ equity (deficiency)	472,644	642,064
Series B Convertible Preferred Stock [Member]
Stockholders’ equity (deficiency):
Convertible Preferred Stock	76,095	76,095
Series C Convertible Preferred Stock [Member]
Stockholders’ equity (deficiency):
Convertible Preferred Stock		705,238
Series E Convertible Preferred Stock [Member]
Stockholders’ equity (deficiency):
Convertible Preferred Stock		1,190,000
Conversion of Series F Preferred Stock Into Common Stock [Member]
Stockholders’ equity (deficiency):
Convertible Preferred Stock	1,591,763
Series G Convertible Preferred Stock and Related Warrants [Member]
Stockholders’ equity (deficiency):
Convertible Preferred Stock	$ 404,250

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).

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).