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Biogen terminates phase 4 efficacy study of aducanumab


Jessica Rinaldi/The Boston Globe

Biogen, the maker of aducanumab has announced that it will terminate the Phase 4 trial required by the FDA for aducanumab, the monoclonal antibody against beta amyloid that received accelerated approval in 2021. The company is also halting production of the compound and relinquishing ownership rights to the original developer, Neurimmune.

Accelerated approval was based on the demonstration in multiple studies that treatment with aducanumab could lower brain amyloid in people with Alzheimer’s disease. But two Phase 3 trials gave contrasting results about aducanumab’s efficacy, preventing the FDA from granting full clinical approval for the medication. A requirement of accelerated approval was that the company conduct a post-approval trial to demonstrate efficacy. Unfortunately, the case of aducanumab now adds to a checkered history of the use of Phase 4 trials to demonstrate efficacy in the face of uncertain results in pivotal trials.