Prothena, an Irish biotech focused on protein dysregulation diseases, is undertaking a major workforce reduction, laying off 63% of employees following the failure of its phase 3 amyloidosis drug birtamimab. Despite prior post hoc data suggesting mortality benefits in a subset of patients, recent results did not meet endpoints, prompting organizational downsizing and strategic refocus. The company expects to maintain a cash reserve of $298 million by year-end and has upcoming data readouts on other pipeline assets partnered with major pharma firms. CEO Gene Kinney expressed gratitude towards departing staff, emphasizing commitment to the mission despite clinical challenges.