The US Food and Drug Administration is expected to issue a regulatory decision Friday on a new Alzheimer's disease treatment as its target action date under the Prescription Drug User Fee Act arrives.

The drug belongs to a class of monoclonal antibodies designed to clear amyloid-beta plaques from the brain, the same mechanism behind Eisai and Biogen's Leqembi and Eli Lilly's Kisunla. Regulators have weighed efficacy data showing modest slowing of cognitive decline against safety concerns involving brain swelling and microhemorrhages known as ARIA.

Clinicians and patient advocacy groups, including the Alzheimer's Association, have pressed for expanded treatment options as an estimated seven million Americans live with the disease. The association has previously urged the FDA and the Centers for Medicare and Medicaid Services to broaden access to amyloid-targeting therapies through reimbursement.

Approval would intensify competition in a market valued by Wall Street analysts in the billions of dollars annually. A complete response letter would require the manufacturer to submit additional data and delay any launch by months or longer.

Neurologists have cautioned that real-world uptake depends heavily on infrastructure for PET imaging, genetic testing for APOE status, and infusion monitoring, which remain limited at many community clinics across the United States.