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v3.25.2

Description of the Business (Details) $ / shares in Units, $ in Thousands |  |  |  |  |  | 6 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 02, 2024 USD ($) $ / shares shares | Apr. 04, 2024 | Mar. 27, 2024 | Dec. 06, 2023 | Nov. 13, 2023 USD ($) $ / shares shares | Jun. 30, 2025 USD ($) $ / shares | Dec. 31, 2024 USD ($) $ / shares
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Common stock, par value (in dollars per share) | $ / shares |  |  |  |  | $ 0.0001 | $ 0.0001 | $ 0.0001
Temporary equity, par value (in dollars per share) | $ / shares |  |  |  |  | $ 0.0001 |  |
Reverse stock split conversion ratio |  | 0.0333 |  |  |  |  |
Cash, cash equivalents, restricted cash and marketable securities | $ |  |  |  |  |  | $ 162,100 |
Restricted cash and cash equivalents | $ |  |  |  |  |  | 1,700 |
Accumulated deficit | $ |  |  |  |  |  | $ 693,895 | $ 692,071
Minimum |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Reverse stock split conversion ratio |  |  | 0.05 |  |  |  |
Maximum |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Reverse stock split conversion ratio |  |  | 0.0333 |  |  |  |
Securities Purchase Agreement |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Sale of stock, number of shares issued in transaction (in shares) | shares |  |  |  |  | 149,330.115 |  |
Total aggregate purchase price | $ |  |  |  |  | $ 60,250 |  |
July 2024 Purchase Agreement |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Sale of stock, price per share (in dollars per share) | $ / shares | $ 20.00 |  |  |  |  |  |
Sale of stock, gross consideration received on transaction | $ | $ 130,000 |  |  |  |  |  |
Common stock | July 2024 Purchase Agreement |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Sale of stock, number of shares issued in transaction (in shares) | shares | 3,563,247 |  |  |  |  |  |
Series B Preferred Stock |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Common stock, par value (in dollars per share) | $ / shares | $ 0.0001 |  |  |  |  |  |
Series B Preferred Stock | July 2024 Purchase Agreement |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Sale of stock, number of shares issued in transaction (in shares) | shares | 2,937,903 |  |  |  |  |  |
Old Cartesian |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Contingent value right, percentage of milestone payments, royalties and other amounts to be distributed |  |  |  | 100.00% |  | 100.00% |
Old Cartesian | Common stock |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Issuance of shares (in shares) | shares |  |  |  |  | 224,099 |  |
Old Cartesian | Preferred stock | Series A Preferred Stock |  |  |  |  |  |  |
Cash and Cash Equivalents [Line Items] |  |  |  |  |  |  |
Issuance of shares (in shares) | shares |  |  |  |  | 384,930.724 |  |

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