Alzheimer’s disease (AD) is the most common cause for dementia worldwide. Until recently, all approved treatments for AD were symptomatic and not disease modifying. On 7 June 2021, the US FDA approved aducanumab, a human IgG1 anti-Aβ monoclonal antibody selective for Aβ aggregates, as the first disease-modifying treatment for AD. Aducanumab is approved in the United States for the treatment of mild cognitive impairment or mild-dementia stage of AD. In this Editorial, we review the trial data for aducanumab in the treatment of AD and the controversies that its approval has generated.