US agency approves new treatment for early Alzheimer’s

The United States Food and Drug Administration (FDA) approved this Friday (6) a new drug against Alzheimer’s disease that can moderately slow the pace of cognitive decline at the onset of the disease, but also carries risks of swelling and bleeding in the brain.

Approval of the drug lecanemab, to be marketed as Leqembi, is likely to attract considerable interest from patients and physicians. Studies of the drug, an intravenous infusion given every two weeks, suggest it holds more promise than the small number of treatments already available. Still, several Alzheimer’s experts said it was unclear from the medical evidence whether Leqembi could slow cognitive decline enough for patients to notice.

Japanese pharmaceutical company Eisai led the development and testing of the drug. It is partnering with the North American Biogen, maker of the controversial drug Aduhelm, also for Alzheimer’s, for its commercialization and marketing, and the companies will split the profits equally. Eisai said the list price of Leqembi (pronounced le-quem-bi) would be US$26,500 (over R$138,000) per year.

In its ruling, the FDA appeared to acknowledge the vehement criticism that arose when it approved Aduhelm in 2021 after a committee of independent advisers and a board of senior federal agency officials said there was insufficient evidence of its effectiveness.

Last week, an 18-month investigation by two congressional committees found that Aduhelm’s approval process was “riddled with irregularities” and involved unusually close collaboration with Biogen. In response, the FDA said “the agency has already begun implementing changes consistent with the committees’ recommendations.”

In Leqembi, the FDA included more strict and cautious language on the drug label than it initially did in Aduhelm. (After protests from doctors and others, it changed the label of Aduhelm a month after its approval.)

Leqembi’s label says the drug should only be used in patients in the early and mild stages of Alzheimer’s disease, matching the status of patients in the drug’s clinical trials. He instructs doctors not to treat patients without testing to confirm that they have one of the main features of Alzheimer’s disease: the buildup of the amyloid protein, which Leqembi attacks, as does Aduhelm.

It is estimated that about 1.5 million of the 6 million people with Alzheimer’s in the United States are in the early stages of the disease, diagnosed with mild or early-stage cognitive impairment. How many are treated with Leqembi will depend significantly on whether Medicare will cover the drug.