FDA grants approval for first Alzheimer's drug slowing disease progression

The FDA granted Leqembi traditional approval yesterday (July 6) to Eisai Co., Ltd and Biogen Inc. for a 100mg/mL injection for intravenous use making it the first and only approved treatment shown to reduce the rate of the disease progression.

LeqembiI demonstrated clinically meaningful slowing of cognitive and functional decline in a patient group generalizable to US Medicare beneficiaries, which included a mix of racial and ethnic groups, patients with common comorbid conditions, concomitant medications and patients with mild cognitive impairment (MCI) due to AD or mild AD.

Collectively referred to as early AD, patients with mild cognitive impairment (MCI) or mild dementia, the population that was treated in the trials, should be initiated with the treatment first.

The traditional approval of Leqembi is based on phase 3 data from Eisai’s large global charity AD clinical trial. The drug met its primary endpoint and all key secondary endpoints with statistically significant results and confirmed the clinical benefit of the drug.

Haruo Naito, chief executive officer at Eisai, said: “The FDA approved Leqembi under the traditional approval pathway, making it the first and only approved anti-amyloid Alzheimer's disease treatment shown to reduce the rate of disease progression and to slow cognitive impairment in the early and mild dementia stages of the disease.

“As a research and development-focused company based on our HHC (human health care) concept, we are proud that the results of Eisai's AD research over the past 40 years have been recognized and delivered to people living with this disease in the United States.”

The primary endpoint was the global cognitive and functional scale, Clinical Dementia Rating Sum of Boxes (CDR-SB). Leqembi treatment reduced clinical decline on CDR-SB by 27% at 18 months compared to placebo.

Additionally, the secondary endpoint of AD Cooperative Study-Activities of Daily Living Scale for Mild Cognitive Impairment (ADCS MCI-ADL), as measured by people caring for patients with AD, noted a statistically significant benefit of 37%.

This measures the ability of patients to function independently, including being able to dress, feed themselves and participate in community activities.

Full results of the Clarity AD study were presented at the Clinical Trials on Alzheimer's Disease (CTAD) 2022 conference and simultaneously published in the peer-reviewed medical journal The New England Journal of Medicine​ on November 29, 2022.

Importantly, following FDA’s traditional approval of Leqembi, Centers for Medicare & Medicaid Service (CMS) confirmed that broader coverage of the drug is now available and released more details on the registry, including the easy-to-use data submission process.

The CMS-facilitated registry is now available for healthcare professionals to submit required patient data to CMS. Eisai is pleased that Medicare will cover this important therapy for appropriate patients. This will facilitate reimbursement for and access to Leqembi across a broad range of healthcare settings in the United States.

“Alzheimer’s disease is a progressive, fatal disease that greatly impacts not only the people living with it, but also their loved ones, care partners and society. We continue to work to create broad and simple access to Leqembi for patients and to support diagnosis and treatment at the early stage of the disease. 2 Eisai will diligently work to educate physicians on the safe and appropriate use of the drug to maximize its benefit to people living with early AD and their families.

“Today marks a breakthrough in the treatment of Alzheimer’s disease, and we are proud to be at the forefront of ushering in a new era of advances for a disease that was previously considered untreatable. We would like to express our sincere appreciation to those who have worked tirelessly to find a treatment for this unrelenting disease, without whom this progress would not be possible,” said Christopher Viehbacher, president, and chief executive officer of Biogen.

"Our focus is now on the path forward, working alongside Eisai with the goal of making Leqembi accessible to eligible patients as soon as possible.”

The drug s a humanized immunoglobulin gamma 1 (IgG1) monoclonal antibody directed against aggregated soluble (protofibril*) and insoluble forms of amyloid beta (Aβ). Critically, Leqembi targets and clears the most neurotoxic form of Aβ that continuously accumulates as well as removes the existing plaques to treat this progressive, chronic disease.

In June 2023, the FDA’s Peripheral and Central Nervous System Drugs (PCNS) advisory committee voted unanimously that the data from Eisai’s Clarity AD clinical trial confirmed the clinical benefit of Leqembi for the treatment of AD.