By Leroy Leo and Julie Steenhuysen

A panel of expert advisers on Friday unanimously agreed that a late-stage trial of Eisai and Biogen's Alzheimer's drug Leqembi verified the benefit of the treatment for those at an early stage of the disease, clearing the way for traditional U.S. approval.

All six advisers on the panel voted in favor of Leqembi for treatment of the mind-wasting illness.

"I believe the benefit versus risk are beneficial, acceptable and in line with this class of therapeutics, especially considering the burden of the disease and the progressive nature of the disease," said panel member Dr. Tanya Simuni, professor of neurology at Northwestern University Feinberg School of Medicine.

Leqembi won accelerated approval by the Food and Drug Administration in January based on its ability to remove toxic amyloid plaques from the brain. The agency is expected to make its decision on traditional approval by July 6.

The accelerated approval restricted Medicare payment of the drug to those in a clinical trial, but no such trials are underway for Leqembi, resulting in negligible sales so far. Most U.S. Alzheimer's patients are Medicare-eligible.

Regular approval would make Leqembi the first in its class of drugs that work by removing sticky amyloid plaques from the brain to achieve the regulatory milestone.

"Overall, it demonstrated clearly that this is an effective treatment in the population as it was defined," said Dr. Robert Alexander, committee chair and an Alzheimer's expert at the Banner Alzheimer's Institute. He added that he thought the study "clearly demonstrated a clinical benefit," calling the results "robust."

Analysts have forecast Leqembi sales topping $1 billion in 2026 and reaching $5.7 billion by 2030.

(Reporting by Leroy Leo and Khushi Mandowara in Bengaluru and Julie Steenhuysen in Chicago; Editing by Bill Berkrot)