After 18 months of LEQEMBI (lecanemab-irmb) intravenous (IV) treatment at 10 mg/kg every two weeks, patients may either continue IV infusions at 10 mg/kg once every four weeks or start the new weekly 360 mg subcutaneous injection using the LEQEMBI IQLIK autoinjector.
Eisai and Biogen have also launched the LEQEMBI CompanionTM program, an initiative rooted in both companies' commitment to providing access to LEQEMBI and resources for people living with early Alzheimer's disease. The program aims to provide expanded resources that support patients throughout their LEQEMBI treatment journey, from initiation through maintenance therapy.
In addition to the current resources already provided (e.g., help with understanding insurance coverage and potential out-of-pocket costs and identifying financial support programs), the new LEQEMBI Companion program will now offer patients:
Injection education through Nurse Educators either in-person or virtually to provide patients with training on injecting their maintenance dose using the LEQEMBI IQLIK (nurse educators train on the device only; patients should discuss any treatment-related questions with their doctor).
A welcome kit that includes educational resources to help patients and care partners know what to expect, prepare for at-home injections, and more.
Designed to serve as a digital solution to help support patients and care partners along their treatment journey, the LEQEMBI Companion app was developed with Medisafe, a digital patient engagement and medication management platform. From educational information about the injection process to a tool for tracking where and when injections occur, the LEQEMBI Companion app offers resources and more all in one place. Patients can visit LEQEMBI.com/CompanionAppSignUp to get started.
To further support access to LEQEMBI for certain patients who need help paying for their medicines, Eisai's Patient Assistance Program (PAP) will provide LEQEMBI and LEQEMBI IQLIK at no cost, for eligible uninsured and underinsured patients, who meet financial need and other program criteria.
To learn more, or if you are already enrolled and have questions, visit LEQEMBI.com/PatientSupport or call 1-833-4-LEQEMBI (1-833-453-7362), Monday-Friday, 8 a.m. to 8 p.m. Eastern Time.
AD is a progressive, relentless disease characterized by formation of protein deposits known as plaques made of amyloid-beta aggregates and neurofibrillary tangles made of tau protein in the brains of people living with AD. It is caused by a continuous underlying neurotoxic process that begins before amyloid plaque accumulation and continues after plaque removal.
The data show that amyloid-beta protofibrils and tau tangles play roles in the neurodegeneration process,4-6 and only LEQEMBI fights AD in two ways – targeting both amyloid plaque and protofibrils*, which can impact tau downstream.
Due to the reaccumulation of AD biomarkers and return to placebo rate of decline after therapy is stopped,4-5 continuing maintenance treatment after the initial 18-month therapy is essential to slow the progression of AD and extend the therapeutic benefits, helping patients maintain who they are for longer.
The availability of LEQEMBI IQLIK in the U.S. offers patients and care partners the ability to use the device at home, shortening treatment time, and providing an option to continue treatment without having to worry about visiting an infusion center. The LEQEMBI IQLIK also has the potential to reduce healthcare resources associated with IV maintenance dosing, such as preparation for infusion and nurse monitoring, while increasing infusion capacity for new eligible patients to begin initiation treatment and streamlining the overall AD treatment pathway.
Eisai serves as the lead for lecanemab's development and regulatory submissions globally with Eisai and Biogen co-commercializing and co-promoting the product and Eisai having final decision-making authority.
Protofibrils are thought to be the most toxic Aβ species that contribute to brain damage in AD and play a major role in the cognitive decline of this progressive and devastating disease. Protofibrils can cause neuronal and synaptic damage in the brain, which can subsequently adversely affect cognitive function through multiple mechanisms.6 The mechanism by which this occurs has been reported not only by increasing the formation of insoluble Aβ plaques, but also by directly damaging signaling between neurons and other cells. It is believed that reducing protofibrils may reduce neuronal damage and cognitive impairment, potentially preventing the progression of AD.5
INDICATION
LEQEMBI® is indicated for the treatment of Alzheimer's disease (AD). Treatment with LEQEMBI should be initiated in patients with mild cognitive impairment (MCI) or mild dementia stage of disease, the population in which treatment was initiated in clinical trials.
C ONTRAINDICATION
Contraindicated in patients with serious hypersensitivity to lecanemab-irmb or to any of the excipients. Reactions have included angioedema and anaphylaxis.
WARNINGS AND PRECAUTIONS
AMYLOID-RELATED IMAGING ABNORMALITIES
Medications in this class, including LEQEMBI, can cause ARIA-E, which can be observed on MRI as brain edema or sulcal effusions, and ARIA-H, which includes microhemorrhage and superficial siderosis. ARIA can occur spontaneously in patients with AD, particularly in patients with MRI findings suggestive of cerebral amyloid angiopathy (CAA), such as pretreatment microhemorrhage or superficial siderosis. ARIA-H generally occurs with ARIA-E. Reported ARIA symptoms may include headache, confusion, visual changes, dizziness, nausea, and gait difficulty. Focal neurologic deficits may also occur. Symptoms usually resolve over time.
Incidence of ARIA
Symptomatic ARIA occurred in 3% and serious ARIA symptoms in 0.7% with LEQEMBI. Clinical ARIA symptoms resolved in 79% of patients during the period of observation. ARIA, including asymptomatic radiographic events, was observed: LEQEMBI, 21%; placebo, 9%. ARIA-E was observed: LEQEMBI, 13%; placebo, 2%. ARIA-H was observed: LEQEMBI, 17%; placebo, 9%. No increase in isolated ARIA-H was observed for LEQEMBI vs placebo.
Incidence of ICH
ICH >1 cm in diameter was reported in 0.7% with LEQEMBI vs 0.1% with placebo. Fatal events of ICH in patients taking LEQEMBI have been observed.
Risk Factors of ARIA and ICH
ApoE ε4 Carrier Status
Of the patients taking LEQEMBI, 16% were ApoE ε4 homozygotes, 53% were heterozygotes, and 31% were noncarriers. With LEQEMBI, ARIA was higher in ApoE ε4 homozygotes (LEQEMBI: 45%; placebo: 22%) than in heterozygotes (LEQEMBI: 19%; placebo: 9%) and noncarriers (LEQEMBI: 13%; placebo: 4%). Symptomatic ARIA-E occurred in 9% of ApoE ε4 homozygotes vs 2% of heterozygotes and 1% of noncarriers. Serious ARIA events occurred in 3% of ApoE ε4 homozygotes and in ~1% of heterozygotes and noncarriers. The recommendations on management of ARIA do not differ between ApoE ε4 carriers and noncarriers.
About lecanemab (generic name, brand name: LEQEMBI ®
Lecanemab is the result of a strategic research alliance between Eisai and BioArctic. It is a humanized immunoglobulin gamma (IgG1) monoclonal antibody directed against aggregated soluble (protofibril) and insoluble forms of amyloid-beta (Aβ).
Lecanemab has been approved in 50 countries and is under regulatory review in 8 countries. In January 2025, the supplemental Biologics License Application (sBLA) for intravenous (IV) maintenance dosing of the treatment was approved in the U.S., and application have been filed in nine (9) countries and regions.
LEQEMBI's approvals in these countries was based on Phase 3 data from Eisai's, global Clarity AD clinical trial, in which it met its primary endpoint and all key secondary endpoints with statistically significant results. The primary endpoint was the global cognitive and functional scale, Clinical Dementia Rating Sum of Boxes (CDR-SB). In the Clarity AD clinical trial, treatment with lecanemab reduced clinical decline on CDR-SB by 27% at 18 months compared to placebo. The mean CDR-SB score at baseline was approximately 3.2 in both groups. The adjusted least-squares mean change from baseline at 18 months was 1.21 with lecanemab and 1.66 with placebo (difference, −0.45; 95% confidence interval [CI], −0.67 to −0.23; P<0.001). In addition, the secondary endpoint from the AD Cooperative Study-Activities of Daily Living Scale for Mild Cognitive Impairment (ADCS-MCI-ADL), which measures information provided by people caring for patients with AD, noted a statistically significant benefit of 37% compared to placebo. The adjusted mean change from baseline at 18 months in the ADCS-MCI-ADL score was −3.5 in the lecanemab group and −5.5 in the placebo group (difference, 2.0; 95% CI, 1.2 to 2.8; P<0.001). The ADCS MCI-ADL assesses the ability of patients to function independently, including being able to dress, feed themselves and participate in community activities. The most common adverse events (>10%) in the lecanemab group were infusion reactions, ARIA-H (combined cerebral microhemorrhages, cerebral macrohemorrhages, and superficial siderosis), ARIA-E (edema/effusion), headache, and fall.
About Eisai Co., Ltd.
Eisai's Corporate Concept is "to give first thought to patients and people in the daily living domain, and to increase the benefits that health care provides." Under this Concept (also known as human health care (hhc) Concept), we aim to effectively achieve social good in the form of relieving anxiety over health and reducing health disparities. With a global network of R&D facilities, manufacturing sites and marketing subsidiaries, we strive to create and deliver innovative products to target diseases with high unmet medical needs, with a particular focus in our strategic areas of Neurology and Oncology.
In addition, we demonstrate our commitment to the elimination of neglected tropical diseases (NTDs), which is a target (3.3) of the United Nations Sustainable Development Goals (SDGs), by working on various activities together with global partners.
For more information about Eisai, please visit www.eisai.com (for global headquarters: Eisai Co., Ltd.), and connect with us on X, LinkedIn and Facebook. The website and social media channels are intended for audiences outside of the UK and Europe.
About Biogen
Founded in 1978, Biogen is a leading biotechnology company that pioneers innovative science to deliver new medicines to transform patient's lives and to create value for shareholders and our communities. We apply deep understanding of human biology and leverage different modalities to advance first-in-class treatments or therapies that deliver superior outcomes. Our approach is to take bold risks, balanced with return on investment to deliver long-term growth.
