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Note 4 - Collaboration Revenue (Details Textual) $ / shares in Units, ¥ in Billions |  |  |  | 1 Months Ended | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 13, 2022 USD ($) shares | Nov. 12, 2020 shares | Jun. 30, 2020 $ / shares shares | Jun. 30, 2022 USD ($) | Nov. 30, 2020 USD ($) | Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Nov. 12, 2022 $ / shares | Sep. 30, 2021 USD ($) | Sep. 30, 2021 CNY (¥) | Dec. 31, 2020 USD ($)
Revenue from Contract with Customer, Including Assessed Tax |  |  |  |  |  | $ 0 | $ 0 |  |  |  |
Research Collaboration and License Agreement with Eli Lilly [Member] | Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |
Redeemable Noncontrolling Interest, Equity, Preferred, Fair Value | $ 3,763,000 |  |  |  |  |  |  |  |  |  | $ 5,267,000
SEED Therapeutics Inc. [Member] | Research Collaboration and License Agreement with Eli Lilly [Member] |  |  |  |  |  |  |  |  |  |  |
Collaboration Agreement,, Maximum Regulatory Development Milestones to be Received |  |  |  |  |  |  |  |  | $ 108,638,000 | ¥ 0.7 |
Collaboration Agreement, Maximum Commercial Milestones to be Received |  |  |  |  |  |  |  |  | 62,079,000 | 0.4 |
Revenue from Contract with Customer, Excluding Assessed Tax |  |  |  |  |  | 0 | 0 |  |  |  |
Revenues |  |  |  |  | $ 780,000 | 3,000 |  |  |  |  |
Derivative Liability |  |  |  |  |  |  |  |  |  |  | $ 278
Revenue from Contract with Customer, Including Assessed Tax |  |  |  |  |  | $ 500,000 | $ 500,000 |  |  |  |
SEED Therapeutics Inc. [Member] | Research Collaboration and License Agreement with Eli Lilly [Member] | Series A-1 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |
Stock Issued for Transfer of Assets, Shares (in shares) | shares |  | 9,631,941 |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) | shares |  | 1,194,030 |  |  |  |  |  |  |  |  |
SEED Therapeutics Inc. [Member] | Research Collaboration and License Agreement with Eli Lilly [Member] | Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues (in shares) | shares | 1,990,000 | 1,990,000 | 1,990,000 |  |  |  |  |  |  |  |
Shares Issued, Price Per Share (in dollars per share) | $ / shares |  |  | $ 2.5125 |  |  |  |  |  |  |  |
Stock Issued During Period, Value, New Issues | $ 5,000,000 |  |  | $ 1,990,000,000 |  |  |  |  |  |  |
Proceeds from Issuance or Sale of Equity |  |  |  | $ 5,000,000 |  |  |  |  |  |  |
SEED Therapeutics Inc. [Member] | Research Collaboration and License Agreement with Eli Lilly [Member] | Additional Series A-2 Preferred Shares [Member] |  |  |  |  |  |  |  |  |  |  |
Shares Issued, Price Per Share (in dollars per share) | $ / shares |  |  |  |  |  |  |  | $ 2.5125 |  |  |
SEED Therapeutics Inc. [Member] | Research Collaboration and License Agreement with Eli Lilly [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement, Equity Investment |  |  |  |  | $ 10,000,000 |  |  |  |  |  |
Jiangsu Hengrui Pharmaceuticals Co., Ltd. [Member] | Dalian Wanchunbulin Pharmaceuticals Ltd. (“Wanchunbulin”) [Member] |  |  |  |  |  |  |  |  |  |  |
Collaboration Agreement, Upfront Cash Payment |  |  |  |  |  |  |  |  | $ 31,039,000 | ¥ 0.2 |

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