AstraZeneca’s Anselamimab Misses Key Endpoint in Late-Stage Amyloidosis Trial

AstraZeneca said its experimental antibody anselamimab failed to meet the primary goal of a late-stage trial in patients with AL amyloidosis, a rare disorder caused by misfolded plasma-cell proteins that accumulate in organs. The phase 3 CARES programme, which enrolled 406 newly diagnosed patients across 19 countries, found that the drug did not significantly cut all-cause mortality or cardiovascular hospitalisations compared with placebo. The company reported that anselamimab was generally well tolerated and delivered what it called a "highly clinically meaningful" benefit in an undisclosed, prespecified subgroup of patients. AstraZeneca plans a fuller analysis of the data and intends to discuss the findings with regulators and present them at an upcoming medical meeting. The setback dims hopes that the antibody, acquired through AstraZeneca’s 2021 purchase of Caelum Biosciences, could become a growth driver for the group’s rare-disease unit Alexion. AL amyloidosis remains an area of high unmet need; many patients progress to organ failure within years of diagnosis. AstraZeneca shares slipped about 0.8% in early trading following the announcement.