FDA Scientists Appear to Offer Major Endorsement of Biogen's Controversial Alzheimer's Treatment

STAT reports that U.S. Food and Drug Administration (FDA) scientists have indicated that Biogen's Alzheimer's disease drug aducanumab has sufficient safety and efficacy for human use. The reviewers wrote that Biogen's data from a large clinical trial was "robust and exceptionally persuasive," while a second study, although finding no significant benefit, agreed with Biogen that the data generally supports the medication's effects. The FDA review appeared to address two key issues — the differing outcomes between its two pivotal studies, and the possibility that a common side effect informed patients whether they were administered treatment or placebo. The side effect, a swelling of the brain called ARIA, was cited by outside experts as creating a bias in the study. However, the FDA reviewers said analysis of the data did not suggest that this effect biased the trial. Yet reviewer Tristan Massie argued that the one positive trial of aducanumab cannot overtake the negative one, concluding that "there is no compelling, substantial evidence of treatment effect or disease slowing and that another study is needed to confirm or deny the positive study and the negative study."