Eisai and Biogen: FDA approve Alzheimer’s mAb lecanemab

Leqembi (lecanemab) has received accelerated approval for Alzheimer’s disease and will be priced at $26,500 per year, roughly half the original price of Biogen’s controversial drug Aduhelm (aducanumab).

The US Food and Drug Administration (FDA) approved Leqembi on Friday for patients with the mild cognitive impairment or mild dementia stage of disease and confirmed presence of Aβ pathology under an accelerated pathway based on reduction in amyloid beta plaques observed in Phase II trial patients.

Marketing authorization holder Eisai has now submitted a supplemental Biologics License Application (sBLA) to the FDA for traditional approval based on Phase III trial data.

Leqembi is a recombinant humanized immunoglobulin gamma 1 (IgG1) monoclonal antibody (mAb) directed against aggregated soluble and insoluble forms of amyloid beta, expressed in a Chinese hamster ovary cell line.

The recommended dosage is 10 mg/kg that must be diluted then administered as an intravenous (IV) infusion over approximately one hour, once every two weeks.

Eisai partnered with Biogen (then known as Biogen Idec) in 2014 to codevelop lecanemab. The deal also provided Eisai with the option to jointly develop and commercialize two of Biogen’s candidates for Alzheimer’s disease, including Aduhelm (aducanumab), which won approval in June 2021. However, questions have arisen around the efficacy of Aduhelm and availability of the drug has been limited by the US government’s Centers for Medicare & Medicaid Services (CMS) program.

SVB Securities’ analyst Marc Goodman described the approval of Leqembi as good news for Alzheimer’s patients, noting: “The label is basically as expected, and Eisai has set the price for Leqembi at $26,500 a year, which is well below the original Aduhelm price of $56,000 and just below its modified price of $28,000.”

Brian Abrahams, an analyst from RBC Capital Markets, agreed the approval was as expected, but noted initial launch will largely be gated by CMS reimbursement and IV infusion capacity, limiting 2023 sales. However, with full approval he noted Eisai and Biogen “can enable $327 million in 2024 sales and a peak out-year opportunity of $9.9 billion.”

Patient group UsAgainstAlzheimer’s also declared the approval as “a major victory” but did criticize the lack of accessibility for most Alzheimer’s patients.

“This drug should be available now,” said chair and cofounder George Vradenburg. “But without Medicare coverage, only the wealthy who can afford to pay will have access to this treatment, leaving it out of reach for millions of people living with Alzheimer’s.”

With doses of Leqembi limited for the next 12 months at least, details regarding manufacturing scale-up are for now unknown. Biogen’s manufacturing network could be utilized, especially after Adulhelm capacity expectations did not materialize. (The firm has a site in Solothurn, Switzerland and a plant in North Carolina with a combined capacity of 198,000 L.)