On 30 November, Eli Lilly and Company announced that donanemab met its primary endpoints for the 6-month analysis in the Phase III TRAILBLAZER-ALZ 4 study. Findings were presented at the 2022 Clinical Trials on Alzheimer's Disease (CTAD) conference in San Francisco (US). The TRAILBLAZER-ALZ 4 study is a multicenter, randomised and open-label Phase III study aiming to compare donanemab to aducanumab on amyloid plaque clearance in people with early symptomatic Alzheimer's Disease (AD). Donanemab and aducanumab are two investigational amyloid-targeting therapies. They were administered via intravenous infusions every four weeks for up to 18 months.
The studies' co-primary endpoints are the percentage of participants who reach complete amyloid plaque clearance at 6 months, as measured by PET scan. Findings showed that brain amyloid clearance was achieved in 37.9% of donanemab-treated participants compared with 1.6% of aducanumab-treated participants at 6 months. In a key secondary outcome, donanemab reduced brain amyloid plaque levels vs. baseline by 65.2% compared with 17.0% for aducanumab at 6 months. The safety profile of both treatments was consistent with their previously published studies. Amyloid-related imaging abnormalities (ARIA) was the most common treatment emergent adverse event in both groups. In the aducanumab group, the incidence of total ARIA was 26.1% with 4.3% being symptomatic. In the donanemab group, the incidence of total ARIA was 25.4% with 2.8% being symptomatic.
For both treatments, all symptomatic cases were related to ARIA-E. TRAILBLAZER-ALZ 4 study is ongoing and will have secondary analyses at 12-month and 18-month. The study is one of five studies that comprise the clinical program to evaluate the efficacy and safety of donanemab. https://investor.lilly.com/news-releases/news-release-details/lilly-shares-positive-donanemab-data-first-active-comparator
