Note 7 - Commitments and Contingencies (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Operating Lease, Expense	$ 400,000	$ 400,000
Operating Lease, Weighted Average Remaining Lease Term (Year)	2 years
Operating Lease, Weighted Average Discount Rate, Percent	9.50%
Research and Development Expense, Total	$ 4,338,974	4,741,130
Patent License Agreement with the Board of Regents of the University of Texas (NSAIDs) [Member]
Research and Development Expense, Total	$ 300,000	$ 400,000

Amount of operating lease expense. Excludes sublease income.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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