Company: PRTA
Filing Date: 2025-11-06
Form Type: 10-Q
Source: 0001559053-25-000044
Chunk: 38

Company: PROTHENA CORP PUBLIC LTD CO
Filing Date: 2025-11-06
Form: 10-Q
Item: Part I, Item 2
Chunk 38
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 and $200.1 million and $222.7 million for t he nine months ended September 30, 2025, and 2024, respectively.

Our research activities are aimed at developing new drug products. Our development activities involve the translation of our research into potential new drugs. Our R& D expenses primarily consist of personnel costs and related expenses, including share-based compensation and external costs associated with clinical activities and drug development related to our drug programs, and preclinical activities related to our discovery programs. We also incurred wind down costs for programs that we are no longer advancing, including birtamimab and PRX012.

Our G& A expenses primarily consist of personnel costs and related expenses, including share-based compensation and consulting expenses.

Research and Development Expenses

Our R& D expense decreased by $21.8 million or 43% for the three months ended September 30, 2025 and decreased by $52.1 million or 30% for the nine months ended September 30, 2025, compared to the same periods in the prior year. The decrease for the three and nine months ended September 30, 2025, compared to the same periods in the prior year, was primarily due to lower clinical trial expenses primarily related to PRX012 wind down, lower personnel expenses and lower manufacturing and consulting expenses.

The following table sets forth the R& D expenses for our major programs (specifically, programs with successful first dosing in a Phase 1 clinical trial and have material expenditures in the periods presented), which were birtamimab, PRX012, PRX019, and other R& D expenses for the three and nine months ended September 30, 2025, and 2024, (in thousands):

                                      Three Months Ended                                        Nine Months Ended                            
                                      September 30,                                             September 30,                                
                                      2025                                2024                  2025                                         
 ─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  Birtamimab (NEOD001)                $                        7,136      $         18,159      $                       52,483       60,908  
  PRX012                                                      14,653                28,093                              47,821       97,900  
  PRX019 (1)                                                   2,192                 1,328                               6,118        2,785  
  Other R& D (2)