Biogen and Eisai have released much-anticipated clinical trial data for their Alzheimer’s disease drug lecanemab. The phase 3 results, published Tuesday, showed a 27% slower rate of cognitive decline in recipients along with a 20% rate of adverse events.
The results’ significance for patients is a matter of debate among expert observers.
Lecanemab is a monoclonal antibody designed to target and reduce the amyloid brain plaques associated with Alzheimer’s. The new data was released following a September announcement that the drug had slowed decline in memory and thinking among almost 900 recipients with early Alzheimer’s disease, when compared with placebo.
A ‘moderate’ effect
In the trial, participants aged 50 to 90 years received 10 mg of lecanemab per kilogram of body weight every two weeks for 18 months. Investigators tracked evidence of amyloid plaques using brain scans or cerebrospinal fluid testing. The drug is administered via intravenous infusion.
Lecanemab reduced amyloid markers in the brain “and resulted in moderately less decline on measures of cognition and function than placebo,” the researchers reported in the New England Journal of Medicine. But the drug also was associated with adverse events. The researchers recommended longer clinical trials to determine its efficacy and safety in early Alzheimer’s use.
Robust or unnoticeable?
The results are “real and robust,” said Christopher van Dyck, MD, of the Yale Alzheimer’s Disease Research Center, according to a report by National Public Radio. Dyck was involved in the study and presented an overview of the new data at the Clinical Trials on Alzheimer’s Disease meeting in San Francisco.
But others said the drug’s effect on cognitive decline would be very small, NPR found.
“It’s very unlikely that these differences are going to be noticeable by individual patients in their everyday lives,” Madhav Thambisetty, MD, of the National Institute on Aging, told the news outlet. Thambisetty was not involved in the study.
There also is a risk-to-benefit consideration, observers noted. Approximately one in five study participants who received lecanemab had an adverse event such as swelling or brain bleeds, NPR reported. The deaths of two participants may have been linked to these effects. Others reported headaches, visual disturbances and confusion.
Coverage restrictions
The Food and Drug Administration is expected to decide whether lecanemab will be granted accelerated approval by January 6. Yet even if the drug is approved, patients and clinicians may face coverage challenges, BioPharmaDive reported.
Medicare restricted coverage for anti-amyloid Alzheimer’s drugs to clinical trials earlier in 2022 following the controversial approval of the anti-amyloid drug aducanumab (Aduhelm). A national coverage determination is a relatively rare process for the Centers for Medicare & Medicaid Services, and the Alzheimer’s Association called it an unprecedented barrier for patients with a fatal disease hoping to access an FDA-approved treatment.
The organization is urging CMS to modify benefits coverage in advance of lecanamab’s potential approval. The stage 3 data confirm that the treatment can “meaningfully change” the course of early Alzheimer’s disease, it said in a statement.
Unlocking reimbursement
“These peer-reviewed, published results show lecanemab will provide patients more time to participate in daily life and live independently,” it said. “CMS has pledged to move quickly to modify the [national coverage determination] if warranted by new evidence. This evidence has now been delivered and CMS can begin its review immediately,” it said.
According to BioPharmaDive, analysts expect Eisai’s positive late-stage results will “help unlock broader reimbursement, but that will take additional time.”
