Prothena announced a major restructuring involving layoffs of approximately 63% of staff following the unsuccessful phase 3 trial of birtamimab, a monoclonal antibody aimed at treating advanced AL amyloidosis. The trial did not demonstrate mortality improvement, prompting the biotech to cease development and reduce organizational size. Despite this setback, Prothena retains other pipeline assets in collaboration with large pharma partners and anticipates data readouts on Alzheimer’s disease programs later this year. The financial adjustments reflect the challenging landscape for orphan disease therapeutics and emphasize strategic realignment toward sustainable operations.