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v3.25.2

Note 1 - Organization and Basis of Presentation (Details Textual) $ / shares in Units, $ in Thousands |  |  |  |  |  |  | 1 Months Ended | 2 Months Ended | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 28, 2025 USD ($) $ / shares shares | Jun. 30, 2025 USD ($) $ / shares shares | May 14, 2025 USD ($) $ / shares shares | May 12, 2025 USD ($) | Jun. 03, 2024 USD ($) | May 14, 2024 USD ($) | Aug. 14, 2025 USD ($) $ / shares shares | Aug. 11, 2025 shares | Apr. 30, 2023 USD ($) | Jun. 30, 2025 USD ($) $ / shares shares | Jun. 30, 2025 USD ($) $ / shares shares | Jun. 30, 2025 USD ($) $ / shares | Mar. 31, 2025 USD ($) | Jun. 30, 2024 USD ($) | Mar. 31, 2024 USD ($) | Jun. 30, 2025 USD ($) $ / shares shares | Jun. 30, 2024 USD ($) | May 13, 2025 USD ($) | Mar. 01, 2025 USD ($) | Dec. 31, 2024 USD ($) | Mar. 01, 2021 USD ($)
Cash, Cash Equivalents, and Short-Term Investments |  | $ 28,700 |  |  |  |  |  |  |  | $ 28,700 | $ 28,700 | $ 28,700 |  |  |  | $ 28,700 |  |  |  |  |
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (57,779) | $ (87,765) |  |  |  |
Net Income (Loss) Attributable to Parent |  |  |  |  |  |  |  |  |  |  |  | (25,424) | $ (33,460) | $ (56,041) | $ (37,184) | (58,884) | (93,225) |  |  |  |
Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount, Current |  | 7,627 |  |  |  |  |  |  |  | 7,627 | 7,627 | 7,627 |  |  |  | 7,627 |  |  |  | $ 0 |
Long-Term Debt, Gross |  | $ 167,804 |  |  |  |  |  |  |  | $ 167,804 | $ 167,804 | 167,804 |  |  |  | 167,804 |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6,287 | $ 0 |  |  |  |
At the Market Equity Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400,000 |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  | $ 2,100 |  |  |  |  |  |  |  |  | $ 6,400 |  |  |  |  |
Equity Offering Facility, Maximum Aggregate Offering Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 150,000 |  | $ 150,000
Subsequent Event [Member] | Securities Purchase Agreement With Polar Asset Management [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues | shares | 5,365,853 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share | $ / shares | $ 4.1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Premium Over Stock Price, Percentage | 14.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock | $ 20,600 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | At the Market Equity Offering Program [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues | shares |  |  |  |  |  |  | 700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share | $ / shares |  |  |  |  |  |  | $ 3.14 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Common Stock |  |  |  |  |  |  | $ 2,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion of the 2026 Notes Into 2029 Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Original Debt, Amount |  |  | $ 70,800 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion of the 2026 Notes Into Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Original Debt, Amount |  |  | $ 10,000 | $ 10,000 |  | $ 10,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Threshold Trading Days |  |  | 20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued | shares |  | 539,320 | 10,000,000 |  |  |  |  |  |  | 539,320 | 539,320 |  |  |  |  |  |  |  |  |  |
Conversion of the 2026 Notes Into Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued | shares |  |  |  |  |  |  | 1,996,555 | 1,996,555 |  |  |  |  |  |  |  |  |  |  |  |  |
The Credit and Guaranty Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Required Unrestricted Cash |  | $ 25,000 |  |  | $ 25,000 |  |  |  |  | $ 25,000 | $ 25,000 | $ 25,000 |  |  |  | $ 25,000 |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 13.17% |  |  |  |  |  |  |  | 13.17% | 13.17% | 13.17% |  |  |  | 13.17% |  |  |  |  |
Debt Instrument, Maturity Date |  |  |  |  | Jun. 03, 2028 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible Senior Notes 2026 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 5.25% | 5.25% |  |  |  |  |  |  | 5.25% | 5.25% | 5.25% |  |  |  | 5.25% |  |  |  |  |
Debt Instrument, Maturity Date |  |  | Jun. 15, 2029 |  |  |  |  |  |  |  |  |  |  |  |  | Feb. 15, 2026 |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  | $ 18.4875 |  |  |  |  |  |  |  | $ 18.4875 | $ 18.4875 | $ 18.4875 |  |  |  | $ 18.4875 |  |  |  |  |
Debt Instrument, Convertible, Threshold Trading Days |  |  | 20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt, Gross |  | $ 17,017 | $ 17,100 |  |  |  |  |  |  | $ 17,017 | $ 17,017 | $ 17,017 |  |  |  | $ 17,017 |  | $ 97,900 |  | $ 97,178 |
Debt Instrument, Covenant, Mandatory Prepayment |  |  | $ 20,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
The 2029 Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 9.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Period After Conversion Date for Interest Payment |  |  | 18 months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Maturity Date |  |  | Jun. 15, 2029 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  |  | $ 6.18 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Threshold Trading Days |  |  | 20 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt, Gross |  | $ 63,474 |  |  |  |  |  |  |  | $ 63,474 | $ 63,474 | $ 63,474 |  |  |  | $ 63,474 |  |  |  |  |
PDE7 [Member] | National Institute on Drug Abuse (“NIDA”) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Grants Receivable |  |  |  |  |  |  |  |  | $ 6,200 |  |  |  |  |  |  |  |  |  |  |  |
Grants Receivable, Period |  |  |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |
Revenue from Contract with Customer, Excluding Assessed Tax |  |  |  |  |  |  |  |  | $ 1,500 |  |  |  |  |  |  |  |  |  |  |  |

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