PRTA Dives 53.5% YTD: Will the Restructuring Effort Boost Prospects?

Core Viewpoint - Prothena Corporation (PRTA) has faced significant challenges, including a 53.5% decline in shares year-to-date, primarily due to pipeline setbacks and a major workforce reduction of 63% to cut operating costs [1][2]. Financial Outlook - PRTA has revised its annual guidance, expecting a net cash burn of $170-$178 million for 2025, with an estimated cash position of approximately $298 million [3]. - The company anticipates a net loss between $240 million and $248 million for 2025, an increase from previous estimates of $197-$205 million [3]. - The estimated loss includes $105-$110 million in operating expenses related to the discontinued birtamimab program and reorganization costs [4]. Pipeline Developments - The discontinuation of birtamimab, a key pipeline candidate, followed the failure of the phase III AFFIRM-AL study to meet its primary endpoint [6][7]. - Despite the setback with birtamimab, partner Roche is advancing the pipeline candidate prasinezumab into phase III development for early-stage Parkinson's disease, which could provide financial benefits to PRTA through royalties and milestone payments [11][12]. Future Programs - PRTA is expecting initial data from a phase I study on its PRX012 program for Alzheimer's disease in August [13]. - The company is also collaborating with Novo Nordisk on Coramitug for ATTR amyloidosis and with Bristol Myers on several early-stage neurological programs, including BMS-986446 for Alzheimer's disease [13][14][15].