The Food and Drug Administration (FDA) on Friday approved lecanemab for the treatment of Alzheimer’s disease. Lecanemab (brand name Leqembi) is the second monoclonal antibody approved for Alzheimer’s that targets a biological component of the disease. The approval of the other monoclonal antibody called aducanumab (Aduhelm) in 2021 was met with some controversy. Both medications attach to amyloid proteins in the brain and prevent the formation of amyloid plaques, which are associated with Alzheimer’s.
Lecanemab was approved under the FDA’s accelerated approval pathway, which expedites the approval of medications for life-threatening illnesses by allowing companies to use surrogate endpoints (in this case amyloid buildup) rather than wait potentially years before clinical benefits become evident. According to the drug label, lecanemab should be initiated in individuals with mild cognitive impairment or mild dementia.
“Alzheimer’s disease immeasurably incapacitates the lives of those who suffer from it and has devastating effects on their loved ones,” said Billy Dunn, M.D., director of the FDA Office of Neuroscience in a news release by the FDA. “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.”
Lecanemab’s efficacy was demonstrated in a phase 3 clinical trial of 1,795 participants whose results were recently published in the New England Journal of Medicine. Adults aged 50 to 90 with mild cognitive impairment or mild dementia and amyloid buildup (confirmed via a PET scan or cerebrospinal fluid testing) were randomly assigned to receive lecanemab (10 mg/kg) or placebo infusions every two weeks for 18 months.
After 18 months, the adults who received lecanemab showed significant reductions in amyloid buildup relative to those who received placebo, as well as slightly slower declines in cognitive performance. For example, average Clinical Dementia Rating–Sum of Boxes (CDR-SB) scores rose by 1.21 points in the lecanemab group compared with 1.66 points in the placebo group.
The participants who received lecanemab experienced a higher rate of adverse events compared with those who received placebo. Infusion-related side effects such as nausea or vomiting occurred in 26.4% of lecanemab participants compared with 7.4% of placebo participants. Additionally, amyloid-related imaging abnormalities (known as ARIAs)—which may indicate swelling or bleeding in the brain—occurred in 21.5% of lecanemab participants compared with 9.5% of placebo participants.
Kostas Lyketsos, M.D., the Elizabeth Plank Althouse Professor for Alzheimer’s Research at Johns Hopkins Medicine, said that the approval of lecanemab is a positive development, but far from a breakthrough given the modest cognitive benefits, side effects associated with the medication, and high cost ($26,500 for a year). However, he noted that the approval may lead Eisai and Biogen (developers of lecanemab) to design trials exploring whether the medication might prevent or slow cognitive impairment in adults with amyloid buildup but no other symptoms.
Additional coverage of the drug’s approval will appear in Psychiatric News.
What Happens When the Public Health Emergency Ends?
Since March 2020, psychiatrists have been practicing under flexibilities granted by state and federal governments. These flexibilities were intended to ensure access to care during the Public Health Emergency (PHE). APA members are invited to participate in a webinar on Wednesday, January 11, at 1 p.m. ET that will describe the changes that will take place once the PHE ends and how psychiatrists can continue to practice in a way that meets their patients’ needs.