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prothena Prothena Reports First Quarter 2021 Financial Results and Provides Updated Financial Guidance and R & D Update May 11 , 2021 • Net cash used in operating and investing activities was $ 33.7 million in the first quarter ; quarter - end cash and restricted cash position of $ 345.7 million provides funding to advance the R & D pipeline • Announced confirmatory Phase 3 AFFIRM - AL study of birtamimab in Mayo Stage IV patients with AL amyloidosis under SPA agreement with FDA • Achieved $ 60 million milestone from Roche for first patient dosed in Phase 2b PADOVA study of prasinezumab in patients with early Parkinson's disease • Highlighted data in oral presentations at AD / PD in March and AAN in April for three programs in our neurodegenerative and rare peripheral amyloid pipeline DUBLIN , Ireland , May 11 , 2021 ( GLOBE NEWSWIRE ) -- Prothena Corporation plc ( NASDAQ : PRTA ) , a late - stage clinical company with a robust pipeline of novel investigational therapeutics built on protein dysregulation expertise , today reported financial results for the first quarter of 2021. In addition , the Company provided an update on its R & D programs and 2021 financial guidance . " We recently welcomed Hideki Garren to Prothena as Chief Medical Officer and look forward to his expertise contributing to our transition to a fully integrated research , development and commercial biotechnology company , " said Gene Kinney , Ph.D. , President and Chief Executive Officer of Prothena . " The oral presentations at AD / PD and AAN highlight the continued translation of our differentiated protein dysregulation scientific platform from preclinical findings to clinical benefit for patients across multiple programs in our portfolio . We remain on track for significant news flow this year with the planned initiation of three late - stage clinical studies for birtamimab , prasinezumab and PRX004 . We will advance two programs in our Alzheimer's portfolio towards the clinic over the next 12 months , with IND filings for our anti - tau PRX005 and anti - abeta PRX012 programs , designed to be best - in - class treatments for Alzheimer's disease . Additionally , our cash position was strengthened by our public offering in March and will be further bolstered when we receive the $ 60 million milestone earned from Roche . Together this enhances our ability to fund the company through multiple key clinical milestones . " First Quarter and Recent Highlights : Birtamimab , a potential treatment for AL amyloidosis , is a humanized monoclonal antibody designed to directly neutralize soluble toxic aggregates and promote clearance of amyloid that causes organ dysfunction and failure • Based on the significant survival benefit favoring birtamimab , from the previous VITAL study in a subset of patients categorized as Mayo Stage IV at baseline ( HR = 0.413 , p = 0.025 , over 9 months ) , and multiple in - depth discussions with the U.S. Food and Drug Administration ( FDA ) , Prothena announced plans in February 2021 to advance birtamimab into the confirmatory Phase 3 AFFIRM - AL study in Mayo Stage IV patients with AL amyloidosis . AFFIRM - AL is a global , registration - enabling Phase 3 study that will be conducted under a Special Protocol Assessment ( SPA ) agreement with FDA to enable registration at p≤0.10 for the primary endpoint of all - cause mortality . Prasinezumab , a potential treatment for Parkinson's disease , is a humanized monoclonal antibody designed to target a key epitope within the C - terminus of alpha - synuclein and is the focus of the worldwide collaboration with Roche • $ 60 million milestone earned with first patient dosed in PADOVA study in the second quarter • Two oral presentations by Roche at the 15th International Conference on Alzheimer's and Parkinson's Diseases ( AD / PD 2021 ) released new data from Part 1 of the Phase 2 PASADENA study . The first presentation highlighted newly presented data from a pre - specified exploratory subgroup analysis showing slowing of clinical decline with prasinezumab was more evident in subgroups with more rapid disease progression . Separately , new digital biomarker data presented from Roche's remote monitoring technology used in the study was consistent with a potential disease modifying effect of prasinezumab in slowing Parkinson's disease progression . PRX004 , a potential treatment for ATTR amyloidosis , is a humanized monoclonal antibody designed to deplete the pathogenic , non - native forms of the TTR protein • Oral presentation at the American Academy of Neurology ( AAN ) 2021 Virtual Meeting featuring results from the Phase 1 study of PRX004 in ATTR amyloidosis . PRX004 showed favorable results as demonstrated by slowing of neuropathy progression for all 7 evaluable patients at 9 months , including improvement in neuropathy in 3 of the 7 patients , and improved cardiac systolic function for all 7 patients . In this Phase 1 study , PRX004 was found to be generally safe and well tolerated across all dose levels .