Eli Lilly's Alzheimer's drug candidate slowed cognitive decline by 35 percent in a phase 3 study, but the trial revealed some safety risks, including two deaths from brain swelling and nearly 1 in 4 participants experiencing amyloid-related imaging abnormalities.
The drug donanemab met all endpoints in the study that involved 1,736 participants and spanned 18 months, according to a May 3 news release from Eli Lilly. "Participants on donanemab had 40 percent less decline in ability to perform activities of daily living at 18 months," the release said, "and participants on donanemab experienced a 39 percent lower risk of progressing to the next stage of disease compared to placebo."
For adverse effects, MRIs detected swelling of the brain in 24 percent of treated patients, and 6.1 percent experienced this symptom. Among the donanemab group, 31.4 percent reported microhemorrhages or superficial siderosis, compared to 13.6 percent in the placebo group.
Two participants' deaths are attributed to these amyloid-related imaging abnormalities, and a third death happened "after an incident of serious ARIA," the drugmaker said.
A similar case happened with Eisai and Biogen's recently approved Alzheimer's drug, Leqembi (lecanemab), in which its phase 3 study recorded three patient deaths.
Eli Lilly said it would work toward FDA approval.