Like its controversial cousin aducanumab (Aduhelm, Biogen/Eisai), lecanemab was approved under the FDA’s accelerated approval pathway, which can be used to fast-track a drug that provides a meaningful therapeutic advantage over existing treatments for a serious or life-threatening illness.
Unlike aducanumab, however, there was no formal FDA advisory committee meeting on lecanemab prior to approval.
“Alzheimer’s disease immeasurably incapacitates the lives of those who suffer from it and has devastating effects on their loved ones,” Billy Dunn, MD, director of the Office of Neuroscience in the FDA’s Center for Drug Evaluation and Research, said in a press release.
“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,” Dr. Dunn added.
Eisai has reported that lecanemab will cost $26,500 a year.
Modest benefit, adverse events
The FDA noted, “The labeling states that treatment with Leqembi should be initiated in patients with mild cognitive impairment or mild dementia stage of disease, the population in which treatment was studied in clinical trials.”
The agency approved the treatment on the basis of findings from the CLARITY AD trial, which showed modest cognitive benefit for patients with early AD – but at a cost of increased risk for amyloid-related edema and effusions.
The trial enrolled 1,795 adults with mild cognitive impairment or early Alzheimer’s disease in whom amyloid pathology in the brain had been confirmed. Treatment consisted of lecanemab 10 mg/kg biweekly or matching placebo.
After 18 months of treatment, lecanemab slowed cognitive decline by 27%, compared with placebo, as measured by the Clinical Dementia Rating–Sum of Boxes (CDR-SB). This was an absolute difference of 0.45 points (change from baseline, 1.21 for lecanemab vs. 1.66 with placebo; P < .001).
While the results are “welcome news,” a 0.45-point difference on the CDR-SB might not be clinically meaningful, authors of a recent editorial in The Lancet cautioned.
Amyloid-related imaging abnormalities that manifest as edema or microhemorrhages also occurred in one in five patients taking lecanemab.
In addition, a newly published case report in The New England Journal of Medicine describes a patient with Alzheimer’s disease who was taking lecanemab and who died after experiencing numerous intracerebral hemorrhages during treatment with tissue plasminogen activator (tPA) for acute ischemic stroke.
“The findings raise the possibility of cerebral hemorrhages and necrotizing vasculopathy associated with tPA infusion in a patient with cerebrovascular amyloid who had received lecanemab,” the authors wrote.
Alzheimer’s Association reaction
Still, in anticipation of accelerated approval of lecanemab and the antiamyloid drug donanemab (Eli Lilly), which the FDA has also fast-tracked, the Alzheimer’s Association filed a formal request last month with the Centers for Medicare & Medicaid Services asking that it provide full and unrestricted coverage for FDA-approved Alzheimer’s disease treatments.
In a letter addressed to CMS administrator Chiquita Brooks-LaSure, the association asked the agency to remove the requirements for “coverage with evidence development” in its national coverage determination for FDA-approved antiamyloid monoclonal antibodies.
“Each day matters when it comes to slowing the progression of this disease,” Joanne Pike, DrPH, president and CEO for the Alzheimer’s Association, noted in a news release at the time.
“The current CMS policy to severely limit access to these treatments eliminates people’s options, is resulting in continued irreversible disease progression, and contributes to greater health inequities. That’s not acceptable,” Dr. Pike added.
After news of today’s approval was released, Dr. Pike noted in a new release, “The Alzheimer’s Association welcomes and celebrates this action by the FDA. We now have a second approved treatment that changes the course of Alzheimer’s disease in a meaningful way for people in the early stages of the disease.”
Maria C. Carrillo, PhD, chief science officer at the Alzheimer’s Association, called today’s approval “a milestone achievement.”
“The progress we’ve seen in not only this class of treatments but also in the diversification of treatment types and targets over the past few years is exciting and provides real hope to those impacted by this devastating disease,” Dr. Carrillo said.