Doctors also worried about the drug’s serious safety risks, especially in light of its uncertain benefit. Aduhelm can cause brain swelling or brain bleeding.
The concerns were so great that Medicare moved to sharply limit coverage of Aduhelm, making it available only to patients in clinical trials. Medicare covers Alzheimer’s drugs with full approval, which Aduhelm lacked.
Aduhelm brought in only $7.8 million in its first year and a half on the market. Since then, Biogen’s revenue from the drug has been so small that the company no longer reports the details.
Biogen said on Wednesday that it was not acting because of any concerns about the drug’s safety or effectiveness. Now, the rights to Aduhelm will go back to the Swiss company Neurimmune, which had licensed the drug to Biogen.
Biogen will continue to supply monthly infusions of the drug to current patients in the commercial market until November and to those in the confirmatory clinical trial through May. On Nov. 1, Biogen’s license to sell the drug in the United States will be withdrawn.