v3.23.2

Note 1 - Organization and Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, $ in Thousands |  |  |  |  |  | 1 Months Ended | 12 Months Ended | 87 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 25, 2022 $ / shares | Sep. 23, 2022 | May 31, 2022 USD ($) | Jan. 01, 2022 USD ($) | Sep. 18, 2015 USD ($) | May 31, 2022 | Sep. 30, 2015 USD ($) | Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) $ / shares | Dec. 31, 2022 USD ($) $ / shares | Jul. 14, 2021 USD ($) | May 30, 2019 USD ($)
Consideration Paid for Termination of Royalty Monetization |  |  | $ 100 |  |  |  |  | $ 100 |  | $ 100 |  |
Non-cash Gain on Termination of Liability Related to Sale of Future Royalties |  |  | $ 84,100 |  |  |  |  | $ 84,152 | $ (0) |  |  |
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares | $ 0.001 |  |  |  |  |  |  | $ 0.001 | $ 0.001 | $ 0.001 |  |
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent |  |  |  |  |  | 40.00% |  |  |  |  |  |
Restructuring Charges, Total |  |  |  |  |  |  |  | $ 500 |  |  |  |
Proceeds From Sale of Royalty and Milestone Rights |  |  |  |  | $ 65,000 |  | $ 65,000 |  |  |  |  |
Royalty Arrangment Maximum Payments |  |  |  |  |  |  | 195,000 |  |  |  |  |
Net Proceeds from Sale of Future Royalties |  |  |  |  |  |  | $ 61,200 | $ 0 |  | $ 61,184 |  |
Accounting Standards Update 2021-04 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Payments of Stock Issuance Costs |  |  |  | $ 700 |  |  |  |  |  |  |  |
Adjustments to Additional Paid in Capital, Modification of Warrants |  |  |  | $ 100 |  |  |  |  |  |  |  |
Loan Agreement with Oxford Finance LLC [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Minimum Required Unrestircted Cash |  |  |  |  |  |  |  |  |  |  |  | $ 5,000
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life (Year) |  |  |  |  |  |  |  | 5 years |  | 5 years |  |
Reverse Stock Split [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio | 20 |  |  |  |  |  |  |  |  |  |  |
Reverse Stock Split [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio |  | 10 |  |  |  |  |  |  |  |  |  |
Reverse Stock Split [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Stockholders' Equity Note, Stock Split, Conversion Ratio |  | 30 |  |  |  |  |  |  |  |  |  |
Aguettant [Member] | PFS Products [Member] |  |  |  |  |  |  |  |  |  |  |  |
License Agreement, Milestone Payments to be Paid, Maximum |  |  |  |  |  |  |  |  |  |  | $ 24,000 |

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