ALEC Stock Tanks as Alzheimer's Drug Fails in Mid-Stage Study

Core Viewpoint - Alector, Inc. experienced a significant decline in stock price following the announcement of disappointing results from its midstage study of AL002 for early Alzheimer's disease, leading to a 35.1% drop in shares on November 26 [1]. Study Results - The phase II INVOKE-2 study aimed to evaluate the safety and efficacy of AL002 in slowing disease progression in early Alzheimer's disease, with the primary endpoint being the Clinical Dementia Rating Sum of Boxes (CDR-SB) scale [2]. - AL002 did not meet the primary endpoint of slowing clinical progression as measured by the CDR-SB, and there were no favorable treatment effects on secondary clinical and functional endpoints [3]. - The study also showed no significant effects on Alzheimer's fluid biomarkers or reductions in brain amyloid levels, although some positive signs of sustained target engagement and microglial activation were noted [4]. Company Response - Following the study results, Alector decided to discontinue the open-label extension study of AL002 [5]. - The company plans to present the data at a future scientific conference and is focusing on developing other candidates for neurodegenerative diseases, including latozinemab (AL001) and AL101/GSK4527226 in collaboration with GSK plc [6][7]. Future Plans - Alector is currently conducting the phase III INFRONT-3 study for latozinemab targeting frontotemporal dementia with a progranulin gene mutation, with top-line data expected in late 2025 or early 2026 [7]. - The phase II PROGRESS-AD study is evaluating AL101/GSK4527226 for early Alzheimer's disease, with over one-third of the target enrollment already achieved [8]. - To align resources for pipeline development, Alector plans to reduce its workforce by nearly 17% [8]. Financial Position - As of September 30, 2024, Alector reported cash, cash equivalents, and investments totaling $457.2 million, which is expected to fund operations through 2026 [9]. Market Context - Currently, there are two FDA-approved drugs for early symptomatic Alzheimer's disease: Leqembi and Kisunla, both targeting the reduction of amyloid beta plaque accumulation in the brain [10][11].