On 7 June 2021, aducanumab was granted accelerated approval for the treatment of 
Alzheimer disease (AD) by the FDA on the basis of amyloid-lowering effects 
considered reasonably likely to confer clinical benefit. This decision makes 
aducanumab the first new drug to be approved for the treatment of AD since 2003 
and the first drug to ever be approved for modification of the course of AD. 
Many have questioned how scientific evidence, expert advice and the best 
interests of patients and families were considered in the approval decision. In 
this article, we argue that prior to approval, the FDA and Biogen's shared 
interpretation of clinical trial data - that high-dose aducanumab was 
substantially clinically effective - avoided conventional scientific scrutiny, 
was prominently advanced by patient representative groups who had been major 
recipients of Biogen funds, and raised concerns that safeguards were 
insufficient to mitigate regulatory capture within the FDA. Here, we reflect on 
events leading to the FDA's decision on 7 June 2021 and consider whether any 
lessons can be learned for the field.