Company: PRTA
Filing Date: 2025-02-27
Form Type: 10-K
Source: 0001559053-25-000009
Chunk: 23

Company: PROTHENA CORP PUBLIC LTD CO
Filing Date: 2025-02-27
Form: 10-K
Item: Item 1
Chunk 23
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 order to further explore the observed effects in both studies. Roche will continue to evaluate the data and work together with health authorities to determine next steps.

Phase 2 PASADENA Clinical Trial

The results from the Phase 1 clinical trial further supported advancing prasinezumab into the Phase 2 PASADENA clinical trial. PASADENA was a two-part Phase 2 clinical trial in early Parkinson's disease patients conducted by Roche. Part 1 was a randomized, double-blind, placebo-controlled, three-arm trial and enrolled 316 patients to evaluate the efficacy and safety of prasinezumab in patients over 52 weeks. In part 1, patients were randomized on a 1:1:1 basis to receive one of two active doses (1500 mg or depending on body weight either 3500 mg or 4500 mg) of prasinezumab or placebo via intravenous infusion once every 4 weeks. Patients enrolled in the trial must not have been on dopaminergic therapy and were not expected to require dopaminergic therapy for at least 52 weeks. Part 2 of the trial was a 52-week blinded extension phase in which patients from the placebo arm of the trial were re-randomized onto one of two active doses on a 1:1 basis, so that all participants were on active treatment. Patients who were originally randomized to an active dose will continue at that dose level for the additional 52 weeks. In part 2, patients were allowed to use concomitant dopaminergic therapy. Any patient who medically required initiation of dopaminergic therapy during part 1 had their subsequent data censored for the primary endpoint analysis.

Results from Part 1 of the PASADENA clinical trial were presented in a Top Abstract oral presentation at the International Parkinson and Movement Disorder Society’s MDS Virtual Conference 2020. While the trial did not meet the primary objective, signals of efficacy on multiple pre-specified secondary and exploratory clinical endpoints, including measures of motor function and biomarkers, were demonstrated in both of the prasinezumab arms when compared to placebo. In PASADENA, prasinezumab significantly reduced decline in motor function by 35% (pooled dose levels) vs. placebo after one year of treatment on the centrally rated assessment of Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Part III, a clinical examination of motor function. Motor symptoms associated with Parkinson’s disease include slowness of movement (br