Long-term data presented at the Alzheimer’s Association International Conference show Leqembi can help patients stay in the earlier stages of Alzheimer’s disease as compared to the condition’s natural progression.
Four years of consistent treatment with Biogen and Eisai’s anti-amyloid antibody Leqembi can keep patients with Alzheimer’s in the early stages of the disease for longer, further establishing the efficacy of the biologic as sales start to pick up.
These long-term data, presented Wednesday at the Alzheimer’s Association International Conference in Toronto, come from the open-label extension phase of the Clarity AD study, which measured cognition and function using the Clinical Dementia Rating scale. Results showed that over three years of treatment, patients given Leqembi scored 1.01 points better compared with the expected cognitive decline, as documented in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort, a clinical research project that tracks disease progression in elderly adults who are cognitive healthy, have mild cognitive impairment and early Alzheimer’s disease (AD).
Leqembi’s long-term benefits were more pronounced at the four-year follow-up. Compared with the expected decline in the ADNI, patients scored 1.75 points better on the clinical assessment scale after treatment with the antibody.
These results suggest that Leqembi not only slows the disease progression, but also helps patients “remain in the early stages of AD longer compared to AD’s natural course,” as per the companies’ press announcement. Biogen and Eisai’s readout on Wednesday additionally showed that, in a tau protein substudy of Clarity AD, 69% of patients with early-stage disease showed improvements or no decline in clinical scores after four years of Lecanemab treatment.
“These findings suggest that initiating and maintaining treatment with lecanemab in early-stage AD may help slow clinical decline and may provide sustained benefits over the long term,” the companies said in their press release.
Leqembi is the first fully approved anti-amyloid antibody therapy for Alzheimer’s disease. Despite this distinction, however, the biologic largely underwhelmed on the market, bogged down by poor uptake, especially in the U.S., and questions about its benefit-risk profile. Things have started looking up for Leqembi, however: During Eisai’s third-quarter report for its 2024 fiscal year, the Japanese pharma noted a 30% quarter-on-quarter growth for the biologic, a trend that analysts at Jefferies called “steady” in a February 7 note.
U.S. uptake for Leqembi also appears to be ticking up, with Eisai reporting in February some 13,500 patients in the country receiving treatment. This number comes in “meaningfully ahead” of Jefferies’ expectations.
With sales finally appearing to be on a steady upward track, Biogen and Eisai are now shifting their promotion focus to the clinical benefits of Leqembi. “I think now we can actually focus a lot more on the value proposition and treating patients,” Biogen CEO Chris Viehbacher said during the company’s fourth-quarter earnings call in February. “I think there’s a huge opportunity in expanding the prescriber base.”
