On Jun. 7, 2021, Biogen and Eisai announced that the U.S. Food and Drug Administration (FDA) had granted accelerated approval for ADUHELMﾙ (aducanumab-avwa) as the first and only Alzheimerﾒs disease treatment to address a defining pathology of the disease by reducing amyloid beta plaques in the brain.

Adverse reactions that were reported in at least 2 percent of patients treated with ADUHELM and at least 2 percent more frequently than in patients on placebo were ARIA-E, headache, ARIA-H microhemorrhage, ARIA-H superficial siderosis, fall, diarrhea, and confusion/delirium/altered mental status/disorientation.