Biotech company Prothena announced a substantial workforce reduction, laying off 63% of its employees following the failure of its phase 3 trial for the monoclonal antibody birtamimab targeting Mayo Stage IV AL amyloidosis. The trial did not demonstrate mortality benefits, prompting discontinuation and organizational downsizing. Despite setbacks, Prothena maintains plans for ongoing asset development, including upcoming phase 1 data for PRX012 in Alzheimer’s disease, while partnered assets with major pharma continue progress.