Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 137,573,593	$ 39,553,671
Restricted cash	110,000	110,000
Prepaid expenses	2,550,452	1,813,902
Research and development tax rebate receivable	720,029	634,940
Other current assets	77,239	657,662
Total current assets	141,031,313	42,770,175
Furniture and equipment, net	15,835	20,632
Intangible assets, net	8,917	13,375
Right-of-use asset	8,013	18,053
Other assets	16,468	17,218
Total Assets	141,080,546	42,839,453
Current liabilities
Accounts payable	722,281	1,588,613
Accrued expenses	151,155	93,367
Payroll liabilities	490,001	963,665
Common stock warrant liability		13,003,075
Lease liability	8,013	18,053
Other current liabilities	7,697	4,748
Total current liabilities	1,379,147	15,671,521
Commitments and contingencies (Note 13)
Stockholders' equity
Preferred stock - $0.001 par value; 10,000,000 shares authorized; 620 and 621 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	1	1
Common stock - $0.18 par value; 175,000,000 shares authorized; 120,824,368 and 47,548,835 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	21,748,374	8,558,778
Additional paid-in capital	229,498,725	129,887,146
Accumulated deficit	(112,165,700)	(111,898,992)
Total Stockholders' Equity	139,701,399	27,167,932
Total Liabilities and Stockholders' Equity	141,080,546	42,839,453
Series B Preferred Stock [Member]
Stockholders' equity
Additional paid-in capital - Series B convertible preferred stock	$ 619,999	$ 620,999