Aducanumab

Drug Overview

Aducanumab (Biogen/Eisai) is an intravenous-infused, fully human recombinant immunoglobulin G1 monoclonal antibody. With its N-terminal recognition site, aducanumab targets insoluble fibrils with high affinity and soluble oligomers with weaker affinity. Through this mechanism, the drug reduces the growth of brain plaques, a key pathological feature of Alzheimer’s disease; consequently, the progression of Alzheimer’s disease is expected to be slowed down.

Analyst Outlook

Aducanumab (Biogen/Eisai) is the first amyloid-beta-targeting drug to show target engagement and improvements to both cognitive and functional endpoints in patients with early Alzheimer’s disease. The positive data from the Phase Ib PRIME study prompted the launch of a larger Phase III program, although the high incidences of amyloid-related imaging abnormalities suggestive of sulcal effusion and parenchymal edema (ARIA-E) that were dose- and apolipoprotein E4 (ApoE4)-dependent will require careful mitigation strategies. As such, the success of Biogen’s Phase III program hinges not only on demonstrating clinical efficacy on a newly adopted clinical endpoint, but also controlling ARIA-E manifestations. Unmanageable ARIA-E incidences could result in drug discontinuation and patient drop-outs, impacting the study outcomes.