"This treatment option is the latest therapy to target and affect the underlying disease process of Alzheimer's, instead of only treating the symptoms of the disease," said Dr. Billy Dunn, director of the Office of Neuroscience in the FDA's Center for Drug Evaluation and Research, during the accelerated approval announcement.

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The VA treats roughly 168,000 veterans with Alzheimer's, a portion of whom are in the early stages of the illness.

VA officials said Tuesday that its formulary committee made the decision to cover Leqembi because its members believed that there are patients in the VA system who could benefit from the drug.

Leqembi has an estimated cost of $26,500 a year. A two-milliliter dose at the VA will cost the department $194.63, while a five-milliliter dose will cost $486.57, according to the department's National Acquisition Center Contract Catalog.

It will be available only at the request of a provider to veterans who "most closely align with" patients who meet the selection criteria for clinical trials, according to VA Press Secretary Terrence Hayes, meaning that the VA patients must meet the same demographic and health history standards as those studied by the manufacturers.

"Each dose of the medication administered for each patient will be tracked and monitored for safety and appropriateness of use, in real time, by VA's Center for Medication Safety," Hayes said in an email to Military.com. "VA will continue to monitor the clinical evidence and safety data for this agent and adjust the criteria for use as appropriate. VA also has capabilities and safeguards in place that are very different from the private sector, such as the ability to conduct real-time medication-use evaluations that will allow for continued safe use of the medication."

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Leqembi is approved for use only in patients with early Alzheimer's with a "confirmed presence," via a brain scan, of beta amyloid.

The VA's decision puts additional pressure on the Centers for Medicare and Medicaid Services, or CMS, since the agency decided last year it would not cover the cost of treatments that target beta amyloid outside of clinical trials.

The Alzheimer's Association has pressed Medicare to provide "full and unrestricted" coverage for FDA-approved Alzheimer's treatments.

"When it comes to these treatments, other private insurers tend to follow in Medicare's footsteps. If Medicare holds back, other private insurers tend to hold back, and we have to crack this issue," Alzheimer's Association Chief Public Policy Officer Robert Egge said in a video update Feb. 9 to members.

John Dwyer, president of the Global Alzheimer's Platform Foundation, a research organization based in Washington, D.C., said Tuesday that Medicare should "follow the lead of the VA" and cover the therapy.

"We applaud the VA for its decision to cover Leqembi for veterans in the early stages of Alzheimer's disease. This is a much-deserved victory for the almost 168,000 veterans who have Alzheimer's and receive services through the VA," Dwyer said in a statement emailed to Military.com. "CMS must reverse course on its harmful national coverage decision immediately."

CMS did not respond to a request for comment by publication. Shortly after the FDA issued its decision in January, however, CMS Administrator Chiquita Brooks-LaSure said she understood the impact Alzheimer's has on patients and families.

But, she added, at CMS, "we will continue to expeditiously review the data on these products as they become available and are committed to timely access to treatments, including drugs, that improve clinically meaningful outcomes."

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In 2021, the VA decided against adding an earlier Biogen Alzheimer's drug, Aduhelm, to its list of covered medications out of concerns for risk -- the infusion medication had been linked to brain bleeds and swelling -- and mixed results during clinical trials.

The FDA approved that drug, with an estimated cost of $56,000 a year, on June 7, 2021. But the VA and the Centers for Medicare and Medicaid Services -- the largest market for the therapy, with most of the estimated 6 million Americans with Alzheimer's eligible for Medicare -- opted to sharply limit coverage, even as the price was dropped to $28,200.

Eisai, the Japanese company that paired with Biogen to develop and market Leqembi, said in a statement Monday that it is "proud of and humbled by the opportunity to support U.S. veterans as we strive to fulfill our human health care mission."

"The Veterans Health Administration's careful consideration and timely action to make Leqembi available approximately two months after the FDA approved Leqembi under the accelerated approval pathway shows its continued commitment to veterans living with Alzheimer's Disease," the company wrote in a release.