Consolidated Balance Sheets - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 5,420,708	$ 8,983,717
Contracts and grants receivable	1,018,835	1,201,715
UK research and development incentives receivable	444,043
Prepaid expenses and other current assets	609,739	157,278
Total current assets	7,493,325	10,342,710
Security deposit	22,757	22,734
Office furniture and equipment, net	36,093	19,634
Deferred issuance costs	39,324	59,761
Intangible assets, net	19,699	46,863
Right-of-use lease assets	125,412
Other assets	38,750
Total assets	7,775,360	10,491,702
Current liabilities:
Accounts payable	2,735,442	2,126,215
Accrued expenses	3,157,386	1,790,689
Accrued compensation	298,173	294,628
Lease liabilities - current	121,075
Total current liabilities	6,312,076	4,211,532
Non-current liabilities:
Lease liabilities, net of current	6,149
Total liabilities	6,318,225	4,211,532
Commitments and contingencies
Shareholders' equity:
Preferred stock: 350,000 shares authorized; none issued or outstanding
Common stock, $.001 par value; 50,000,000 shares authorized; 21,753,124 and 17,682,839 shares issued and outstanding at December 31, 2019 and 2018, respectively	21,753	17,683
Additional paid-in capital	177,006,004	172,436,176
Accumulated other comprehensive loss	(45,010)	(3,669)
Accumulated deficit	(175,525,612)	(166,170,020)
Total shareholders' equity	1,457,135	6,280,170
Total liabilities and shareholders' equity	$ 7,775,360	$ 10,491,702