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Commitments and Contingencies (Details) € in Millions |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Nov. 30, 2023 | Oct. 31, 2023 | Aug. 29, 2020 ft² | Jul. 31, 2021 EUR (€) | Jun. 30, 2021 ft² | Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Apr. 30, 2024 USD ($)
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Amount of retention bonuses |  |  |  |  |  | $ 311,000 |  | $ 311,000 |  |
Percentage of retention bonuses | 50.00% |  |  |  |  |  |  |  |  |
Retention bonus paid |  |  |  |  |  |  |  | 86,000 |  |
Severance expense |  |  |  |  |  |  |  | 159,000 |  |
Remains unpaid |  |  |  |  |  |  |  |  |  |
Workforce reduction percentage |  |  |  |  |  |  |  |  | 67.00% |
Number of employees |  |  |  |  |  |  |  |  | 12 |
Square feet (in Square Feet) | ft² |  |  | 5,200 |  |  |  |  |  |  |
Lease term |  |  | 42 months |  |  |  |  |  |  |
Lease renewal option |  |  | option to renew for an additional 36 month term at the then prevailing rental rate. |  |  | to extend the lease term six (6) months through September 2024 |  |  |  |
Term |  |  | 36 months |  |  | 6 months |  |  |  |
Square feet office facilities (in Square Feet) | ft² |  |  |  |  | 3,000 |  |  |  |  |
Sublease term |  | 29 months |  |  | 29 months |  |  |  |  |
Lessee operating lease description |  |  |  |  |  | The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation. |  | The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation. |  |
Lease liability |  |  |  |  |  | $ 48,000 |  | $ 280,000 |  |
Operating leases |  |  |  |  |  | $ 23,000 | $ 33,000 | $ 127,000 | $ 131,000 |
Weighted-average discount rate |  |  |  |  |  | 7.00% |  | 7.00% |  |
Weighted-average remaining lease term |  |  |  |  |  | 6 months |  | 3 years 2 months 12 days |  |
Indicates (true false) whether lessee has option to extend operating lease |  |  |  |  |  | false |  |  |  |
Additional operating lease term |  |  |  |  |  | September 2024 |  |  |  |
Percentage Of Base Rent To Be Paid Monthly |  |  |  |  |  | 125.00% |  |  |  |
One-time Termination Benefits |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | 755,000 |
Subsequent Event |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Amount of retention bonuses |  |  |  |  |  |  |  |  |  | $ 444,000
Clinical development decisions |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Amount of retention bonuses |  |  |  |  |  |  |  |  | 265,000 |
Research and development | One-time Termination Benefits |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | 470,000 |
Research and development | Patent Assignment Agreement | University Medical Center Of Johannes Gutenberg University Mainz |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Royalty obligations (in Euro) | € |  |  |  | € 1.6 |  |  |  |  |  |
General and Administrative Expense |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Rent expense |  |  |  |  |  | $ 22,000 | $ 31,000 | $ 119,000 | 125,000 |
General and Administrative Expense | One-time Termination Benefits |  |  |  |  |  |  |  |  |  |
Commitments and Contingencies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |
Restructuring charges |  |  |  |  |  |  |  |  | $ 285,000 |

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