BRIEF—Aduhelm confirmatory trial design under FDA review

Biogen has submitted the final study protocol for the confirmatory Phase IV ENVISION trial, a requirement of the Accelerated Approval of Aduhelm (aducanumab), for review.

The firm wants to accelerate the timelines for the confirmation process as much as possible. Biogen, which is collaborating with Eisai on the product’s development, expects the trial to take around four years to complete.

The study, as previously announced, will be a global, placebo-controlled trial, aiming to enroll around 1,500 patients with early Alzheimer’s disease.

The primary endpoint for the trial will be measured by the Clinical Dementia Rating–Sum of Boxes (CDR-SB), a commonly-used measure, after 18 months.

The trial will also include a planned long-term extension to collect treatment data for up to four years.