Eisai Co Ltd and Biogen Inc said on Monday that the U.S. Department of Veteran Affairs (VA) will provide coverage of their Alzheimer's treatment Leqembi to veterans at an early stage of the memory-robbing disease.

The VA did not immediately respond to a request for comment, but a document on its website shows that the agency added Leqembi to its list nonformulary drugs, making it available provided patients request it, receive prior approval, and meet strict inclusion criteria for the drug's use.

The VA's coverage comes as initial patient access to the recently approved drug remains limited by a number of factors including reimbursement restrictions by the government's Medicare health program for Americans aged 65 and older, who represent some 90% of individuals likely to be eligible for Leqembi.

The companies set an initial annual price of about $26,500 for Leqembi.

The drug, known chemically as lecanemab, belongs to a class of antibody treatments designed to slow advance of the neurodegenerative disease by removing sticky clumps of the toxic protein beta amyloid from the brain.

Leqembi has so far been approved in the U.S. under the Food and Drug Administration's accelerated review program. Medicare currently restricts drugs in its class approved under that pathway.

The treatment is currently undergoing the FDA's standard review process, which will weigh its impact on cognitive function.

Eisai and Biogen have said they expect full U.S. approval for Leqembi by summer or late this year, which would likely open up coverage by Medicare and other health insurers.