The Food and Drug Administration (FDA) on Friday approved an Alzheimer’s drug that has been shown in clinical trials to slow cognitive decline in patients in the early stages of the disease.

The approval offers patients renewed hope after repeated failures to find effective treatments, even though there have been reports of side effects with the new drug, experts say.

The drug, lecanemab, which will be sold under the name Leqembi, is an infusion of monoclonal antibodies given every two weeks.

The FDA approved Leqembi for use in people with mild cognitive impairment or early Alzheimer’s disease.

The drug was approved in a fast track, which allows for early approval of promising new drugs that «fill an unmet medical need.» At the same time, companies are required to conduct additional clinical trials to confirm the benefits of their drugs or risk removing them from the market.

The agency said its decision was based on a phase 3 clinical trial of 1,795 patients, which found that the drug, developed by drugmakers Eisai and Biogen, slowed cognitive decline in people who received it by 27% after 18 months.

The FDA did not seek the advice of its advisory committee, which it did before controversially approving another Alzheimer’s drug developed by Biogen, called Aduhelm, in 2021.

Leqembi is not a cure; their goal is to slow the progression of the disease by removing clumps of beta-amyloid, long thought by scientists to be a major cause of the disease, from the brain.

The benefit is small, experts say, but adding anything that can give patients more time with family and other loved ones is valuable.

The company has said that the biweekly drug could cost anywhere. between $9,249 to $35,605 annually. The Centers for Medicare & Medicaid Services currently limits coverage for drugs that target amyloid in the brain, so uptake of the new drug may be limited at first, Ivan Cheung, Eisai’s president and CEO, told NBC News. In U.S.A.

Safety concerns have been raised about the drug. at least three dead it may be related to the drug after patients experienced brain swelling or brain bleeding.

According to to the company’s phase 3 trial data, about 12.6% of patients who received the drug experienced brain swelling, compared with only 1.7% of those in the placebo group. About 17% of patients who received the drug experienced a brain hemorrhage, compared with 9% in the placebo group.

Cheung said the company is still «confident» that the drug’s benefits outweigh its risks.

«The disease is devastating,» he said, «and it comes with a lot of emotional turmoil for all the families involved.»

Alzheimer’s is the seventh leading cause of death in the US, according to the Centers for Disease Control and Prevention. Most FDA-approved drugs for Alzheimer’s are aimed at relieving symptoms, not slowing the progression of the disease.

friday announcement It comes on the heels of a scathing congressional report released last week detailing the approval of a different Alzheimer’s drug, called Aduhelm. That drug, developed by Biogen, was approved in 2021 despite an FDA advisory committee finding it unlikely to work. In last week’s report, investigators said the agency failed to meet its own standards and that its approval of Aduhelm was «riddled with irregularities.»

In response to the report, Public Citizen, an advocacy group, sent a letter Wednesday urging the FDA to postpone their decision on whether to approve Leqembi while the companies finish the additional clinical trials needed for full approval.

The drug does have defenders.

Donna Wilcock, associate dean for biomedicine at the University of Kentucky, said Leqembi should be approved. The data supporting Leqembi’s application is «strong,» she said, adding that the trial results are the best «I’ve ever seen for an Alzheimer’s drug in my 25 years.»

The Alzheimer’s Association has said that, based on the results of Eisai and Biogen’s Phase 3 clinical trials, the FDA should approve Leqembi for early-stage Alzheimer’s.

The organization urges the Centers for Medicare & Medicaid Services to review its decision on new treatments for Alzheimer’s. Last year, in response to poor data supporting Aduhelm’s approval, CMS said it would not cover Alzheimer’s drugs that target amyloid unless patients are in a clinical trial.

Making the drug more widely available could mean more patients have «many more months to recognize their spouse, children and grandchildren,» said Maria Carrillo, chief scientific officer for the Alzheimer’s Association.

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