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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables) | 9 Months Ended
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Sep. 30, 2025
Accounting Policies [Abstract] |
Research and Development Expense for Major Programs | The following table sets forth significant research and development (“R&D”) expenses by program as regularly provided to the CODM (in thousands):
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Birtamimab (NEOD001) | $ | 7,136 |  |  | $ | 18,159 |  |  | $ | 52,483 |  |  | $ | 60,908 |
PRX012 | 14,653 |  |  | 28,093 |  |  | 47,821 |  |  | 97,900 |
PRX019 | 2,192 |  |  | 1,328 |  |  | 6,118 |  |  | 2,785 |
Other R&D | 4,957 |  |  | 3,143 |  |  | 13,844 |  |  | 10,754 |
Total R&D | $ | 28,938 |  |  | $ | 50,723 |  |  | $ | 120,266 |  |  | $ | 172,347 |

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