Biogen’s diranersen (BIIB-080) delivered clinical and biomarker signals in the Phase II Celia trial that Biogen is using to support a Phase III push, despite missing the trial’s primary dose-response endpoint. Data presented at the Alzheimer’s Association International Conference (AAIC) showed tau reductions across dose arms and cognitive slowing favoring diranersen over placebo across multiple measures, with the largest effect reported in the lowest-dose group.