WASHINGTON - US. health officials on Friday approved a closely watched Alzheimer's drug that frankly slows the brain-robbing disease, albeit with potential safety risks that patients and their doctors will have to carefully weigh.

The drug, Leqembi, is the first that's been convincingly shown to slow the decline in memory and thinking that defines Alzheimer's by targeting the disease's underlying biology. The Food and Drug Administration approved it for patients with Alzheimer's, specifically those with mild or early-stage disease.

Leqembi, from Japan's Eisai and its U.S. partner Biogen, is a rare success in a field accustomed to dedicated experimental treatments for the incurable condition. The delay in cognitive decline commanded about by the drug likely amounts to just a few months, but Dr. Joy Snider and some other experts say it could level-headed meaningfully improve people's lives.

"This drug is not a cure. It doesn't stop farmland from getting worse, but it does measurably slow the progression of the disease," said Snider, a neurologist at Washington University in St. Louis. "That powerful mean someone could have an extra six months to a year of beings able to drive."

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Snider stressed that the medicine, pronounced "leh-KEM-bee," comes with downsides, including the need for twice-a-month infusions and possible side effects like brain swelling.

The FDA approval came via its accelerated pathway, which allows drugs to launch based on early results, before they're confirmed to benefit patients. The agency's use of that shortcut arrive has come under increasing scrutiny from government watchdogs and congressional investigators.

Last week, a congressional recount found that FDA's approval of a similar Alzheimer's drug named Aduhelm — also from Biogen and Eisai — was "rife with irregularities," incorporating a number of meetings with drug company staffers that went undocumented.

Scrutiny of the new drug, distinguished chemically as lecanemab, will likely mean most patients won't inaugurate receiving it for months, as insurers decide whether and how to screen it.

The drug will cost in $26,500 for a typical year's worth of treatment. Eisai said the note reflects the drug's benefit in terms of improved quality of life, reduced burdens for caregivers and anunexperienced factors. The company pegged its value at over $37,000 per year, but said it priced it flowerbed to reduce costs for patients and insurers. An independent people that assesses drug value recently said the drug would have to be priced beneath $20,600 per year to be cost-effective.

Some 6 million farmland in the U.S. and many more worldwide have Alzheimer's, which gradually attacks areas of the brain needed for memory, reasoning, communication and daily tasks.

The FDA's approval was based on one mid-stage behold in 800 people with early signs of Alzheimer's who were collected able to live independently or with minimal assistance.

Since then, Eisai has originated the results of a larger 1,800-patient study that the FDA will study to confirm the drug's benefit, paving the way for full approval later this year.

The larger behold tracked patients' results on an 18-point scale that measures memory, judgment and other cognitive abilities. Doctors compile the comprising from interviews with the patient and a close contact. After 18 months, patients receiving Leqembi declined more slowly — a contrast of less than half a point on the scale — than patients who received a dummy infusion. The delay amounted to just over five months.

There is cramped consensus on whether that difference translates into real benefits for patients, such as greater independence.

"Most patients won't notice the difference," said Dr. Matthew Schrag, a neurology researcher at Vanderbilt University. "This is really quite a cramped effect and probably below the threshold of what we'd call clinically significant."

Schrag and some latest researchers believe a meaningful improvement would require at least a contrast of one full point on the 18-point scale.

Leqembi works by clearing a sticky brain protein arranged amyloid that's one hallmark of Alzheimer's. But it's not determined exactly what causes the disease. A string of latest amyloid-targeting drugs have failed and many researchers now consider combination treatments will be needed.

Aduhelm, the similar drug, was marred by controversy over its effectiveness.

The FDA celebrated that drug in 2021 against the advice of the agency's own outside experts. Doctors hesitated to prescribe the drug and insurers gratis coverage.

The FDA did not consult the same confidence panel before approving Leqembi.

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While there's "less drama," surrounding the new drug, Schrag said many of the same companies apply.

"Is this slight, measurable benefit worth the hefty stamp tag and the side effects patients may experience?" he expected. "I have pretty serious doubts."

About 13% of patients in Eisai's behold had swelling of the brain and 17% had cramped brain bleeds, side effects seen with earlier amyloid-targeting medications. In most cases those problems didn't cause symptoms, which can implicated dizziness and vision problems.

Also, several Leqembi users died at what time taking the drug, including two who were on blood-thinning medications. Eisai has said the deaths can't be attributed to the drug. The FDA stamp warns doctors to use caution if they prescribe Leqembi to patients on blood thinners.

Insurers are liable to only cover the drug for people like those in the matter study — patients with mild symptoms and confirmation of amyloid buildup. That typically requires expensive brain scans. A separate type of scan will be obligatory to periodically monitor for brain swelling and bleeding.

Speech Therapist And Patient At Home. (Photo By BSIP/UIG Via Getty Images)

A key expect in the drug's rollout will be the coverage exclusive by Medicare, the federal health plan that covers 60 million seniors and latest Americans. The agency severely restricted coverage of Aduhelm, essentially wiping out its U.S. market and prompting Biogen to release marketing plans for the drug.

Eisai executives said they have already exhausted months discussing their drug's data with Medicare officials. Coverage isn't anticipated until after the FDA confirms the drug's benefit, liable later this year.

"Once we have a Medicare exclusive, then we can truly launch the drug across the country," said Eisai's U.S. CEO, Ivan Cheung.

Betsy Groves, 73, of Cambridge, Mass., was diagnosed with Alzheimer's in 2021. A veteran lecturer at Harvard's school of education, she noticed she was having disturbed remembering some student names and answering questions.

Her initial diagnosis, based on a cognitive examination, was later confirmed by a clear test for amyloid.

Groves says she is "more than willing" to try Leqembi, despite potential side effects and the need for infusions.

"For me, the dinky that drug comes on the market — and I get my doctor's approval — I'm progressing to take it," Groves said.