Note 6 - Significant Alliances and Related Parties (Q1) (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Research and Development Expense, Total	$ 118,258	$ 218,208	$ 691,070	$ 1,656,427
RPCI [Member]
Accounts Payable, Related Parties	0	1,197	0	345
Research and Development Expense, Total			1,197	67,896
The Cleveland Clinic [Member]
Accounts Payable, Related Parties			0	0
Research and Development Expense, Total	0	0	0	30,710
BBL [Member]
Research and Development Expense, Total	0	0	0	124
Accounts Receivable, Related Parties, Gross	0	6,285	6,285	6,285
Accounts Receivable, Related Parties	0	6,285
Sublease and Other Income, Related Parties			0	23,106
Incuron [Member]
Accounts Receivable, Related Parties, Gross	130,000	140,595	0	99,285
Accounts Receivable, Related Parties	0	140,595
Revenue from Related Parties	0	41,010	49,357	395,544
Sublease and Other Income, Related Parties	0	0	0	2,268
GPI [Member]
Accounts Receivable, Related Parties, Gross			0	3,700
Sublease and Other Income, Related Parties	0	0	0	7,409
Related Party Transaction, Expenses from Transactions with Related Party	$ 13,440	$ 13,440	$ 53,760	$ 196,975

For an unclassified balance sheet, gross amount of receivables arising from transactions with related parties.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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