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v3.25.3

Summary of Significant Accounting Policies - Additional Information (Details) € in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) financialInstitution lease shares | Sep. 30, 2024 USD ($) shares | Sep. 30, 2025 USD ($) financialInstitution lease shares | Sep. 30, 2024 USD ($) shares | Sep. 30, 2025 EUR (€) financialInstitution lease shares | Dec. 31, 2024 USD ($)
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Cash and cash equivalents | $ 35,132,000 |  | $ 35,132,000 |  |  | $ 35,668,000
Number of financial institutions used for cash deposits | financialInstitution | 2 |  | 2 |  | 2 |
Depreciation expense | $ 40,000 | $ 42,000 | $ 126,000 | $ 99,000 |  |
Impairment losses | 0 | 0 | 0 | 0 |  |
Government assistance, income | $ 0 | $ 703,000 | $ 1,000,000 | $ 742,000 |  |
Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration] | Nonoperating Income (Expense) | Nonoperating Income (Expense) | Nonoperating Income (Expense) | Nonoperating Income (Expense) |  |
Number of existing leases | lease | 3 |  | 3 |  | 3 |
January 2024 Pre-Funded Warrants |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Warrant exercised (in shares) | shares | 8,580,507 | 11,193,564 | 8,580,507 | 11,193,564 | 8,580,507 |
May 2025 Pre-Funded Warrants |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Warrant exercised (in shares) | shares | 86,666,667 |  | 86,666,667 |  | 86,666,667 |
Minimum |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Estimated useful life (in years) | 3 years |  | 3 years |  | 3 years |
Lease term (in months) | 12 months |  | 12 months |  | 12 months |
Maximum |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Estimated useful life (in years) | 13 years |  | 13 years |  | 13 years |
Lease term (in months) | 60 months |  | 60 months |  | 60 months |
United States |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Cash and cash equivalents | $ 26,600,000 |  | $ 26,600,000 |  |  |
Investment interest rate (as a percent) | 4.00% |  | 4.00% |  | 4.00% |
United States | Money market funds |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Investment interest rate (as a percent) | 4.00% |  | 4.00% |  | 4.00% |
Germany |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Cash and cash equivalents | $ 8,400,000 |  | $ 8,400,000 |  |  |
Australian research and development tax incentive | € |  |  |  |  | € 3.5 |
Germany | Money market funds | Minimum |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Investment interest rate (as a percent) | 1.60% |  | 1.60% |  | 1.60% |
Germany | Money market funds | Maximum |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Investment interest rate (as a percent) | 2.75% |  | 2.75% |  | 2.75% |
Australia |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |
Cash and cash equivalents | $ 100,000 |  | $ 100,000 |  |  |
Government R&D assistance rate (as a percent) |  |  | 43.50% |  |  |

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