Lilly's donanemab slows clinical decline of Alzheimer's disease in positive phase II trial.

Donanemab, ( LY3002813) an investigational antibody that targets a modified form of beta amyloid called N3pG, showed significant slowing of decline in a composite measure of cognition and daily function in patients with early symptomatic Alzheimer's disease compared to placebo in results from Eli Lilly and Company's Phase II TRAILBLAZER-ALZ study. Donanemab met the primary endpoint of change from baseline to 76 weeks in the Integrated Alzheimer's Disease Rating Scale (iADRS), slowing decline by 32 percent relative to placebo, which was statistically significant. The iADRS is a clinical composite tool combining the cognitive measure ADAS-Cog13 and functional measure ADCS-iADL, two commonly used measures in Alzheimer's disease. Donanemab also showed consistent improvements in all prespecified secondary endpoints measuring cognition and function compared to placebo, but did not reach nominal statistical significance on every secondary endpoint. By targeting N3pG beta amyloid, donanemab treatment has been shown to rapidly result in high levels of amyloid plaque clearance, as measured by amyloid imaging. In TRAILBLAZER-ALZ, donanemab-treated patients, on average, showed an 84 centiloid reduction of amyloid plaque at 76 weeks compared to a baseline of 108 centiloids (less than 25 centiloids is typical of a negative amyloid scan). In this study, patients stopped receiving donanemab and switched to placebo once their plaque level was below 25 centiloids for two consecutive measures or below 11 centiloids at any one measure. The safety profile of donanemab was consistent with observations from Phase 1 data. Amyloid-related imaging abnormalities (ARIA) were observed, which is consistent with amyloid plaque clearing antibodies. In the donanemab treatment group, amyloid-related imaging abnormalities – edema (ARIA-E) occurred in 27 percent of treated participants, with an overall incidence of 6 percent experiencing symptomatic ARIA-E. .