https://techcrunch.com/2021/06/09/alzheimers-is-open-for-business-controversial-fda-approval-could-pave-the-way-for-future-drugs/

On Monday, a 17-year drought in the world of Alzheimer’s drugs ended with the FDA approval of Biogen’s Aduhlem (aducanumab). The controversy behind the FDA’s decision was considerable, but it doesn’t seem to be spooking drug developers who are now narrowing in on the degenerative brain disease. 

In a nutshell, the approval of Aduhelm came after conflicting results from clinical trials. In November 2020 an independent FDA advisory board did not recommend that the agency endorse the drug, but in June, the agency approved the drug anyway via an Accelerated Approval Program.