Shares of Eisai and Biogen did not move dramatically after the drug companies reported the full results of the clinical trial for their experimental Alzheimer’s disease therapy, but the findings point to a stable future for lecanemab once it is approved by the U.S. Food and Drug Administration.
A study published Tuesday night in the New England Journal of Medicine found that lecanemab moderately slowed the progression of Alzheimer’s in patients with early forms of the disease. The randomized, double-blind Phase 3 trial compared lecanemab with a placebo in 1,795 patients over 18 months.
At the same time the NEJM study came out, Eisai executives presented the findings from the trial at the annual Clinical Trials on Alzheimer’s Disease meeting in San Francisco.
“Everything we heard from the presentation supports our positive view of this product, and we continue to believe that lecanemab should get regular approval based on the positive CLARITY-AD data,” SVB Securities analyst Marc Goodman told investors on Wednesday.
Here are five of Wall Street’s takeaways from the clinical data set:
The full results are in line with the preliminary data previously shared by the companies. The study found that lecanemab reduced cognitive decline by 27% after 18 months, meeting both the primary and secondary endpoints in the clinical trial. The researchers and several Wall Street analysts describe lecanemab as producing a “modest” benefit to the patients enrolled in the study. “Lecanemab reduced markers of amyloid in early Alzheimer’s disease and resulted in moderately less decline on measures of cognition and function than placebo at 18 months but was associated with adverse events,” the study’s researchers concluded. It appears that the drug had an effect “as early as six months and continued to deepen through 18 months,” William Blair’s Myles Minter wrote in an investor note on Wednesday.
There are still safety questions. Two patients died in the trial — one who took lecanemab and one who received the placebo. Although Eisai said the deaths weren’t caused by lecanemab, Goodman said he expects further debate in the medical community about whether it contributed to the death of the patient taking the drug.
Full FDA approval is likely. Eisai and Biogen are expected to file for approval with the U.S. regulator in the first three months of next year, and analysts expect the drug to be fully approved. Aduhelm, the Alzheimer’s drug that the companies brought to market in 2021, received accelerated approval, which then limited its ability to be covered by Medicare and Medicaid. There are still questions about how broad the label for lecanemab will be, meaning which groups of Alzheimer’s patients will be OK’d by the FDA to receive the drug. “We believe [Medicare and Medicaid] will have to offer reimbursement for the drug,” Raymond James analyst Danielle Brill wrote in a note to investors on Tuesday. “The main outstanding questions in our view are: which [Alzheimer’s] populations are the ideal candidates for lecanemab and how broad will adoption be?” Eisai and Biogen can expect lecanemab to generate about $10 billion in sales, according to an RBC Capital Markets estimate.
It’s still unclear which Alzheimer’s patients may qualify for the drug. Patients enrolled in the trial who take blood thinners and received lecanemab were more likely to experience brain bleeding, putting this patient population at higher risk of side effects than those who don’t take anticoagulants. This could become an important distinction: Only 5% of the people enrolled in the study were taking blood thinners, as compared with 25% of the broader Alzheimer’s patient population, according to Mizuho Securities analyst Salim Syed. “This may push the FDA to flag this as a risk in the label,” he wrote. In addition, William Blair’s Minter noted that patients who carry the APOE4 gene appeared to benefit less from lecanemab compared with patients who don’t have the gene, which can increase an individual’s risk of dementia.
It’s evident that Eisai — not Biogen — is leading the charge this time. The failure of Aduhelm seems to be behind the different approach the companies are taking to shepherd lecamemab through the regulatory process. “Perhaps, the oddest piece of the presentation was that ‘Biogen’ was never uttered — and I wonder if this alone will pressure the shares today,” Mizuho’s Syed told investors, “and whether it signals a growing possibility of an oncoming litigation between the partners.”
Eisai’s stock has gained 42.9% this year, while Biogen’s shares have risen 29.1%. The S&P 500
is down 16.9%.