lecanemab lecanemab lecanemab, sold under the brand name leqembi, is a monoclonal antibody medication used for the treatment of alzheimer's disease. lecanemab is an amyloid beta-directed antibody. it is given via intravenous infusion. lecanemabmonoclonal antibodytypewhole antibodysourcehumanizedtargetbeta amyloidclinical datatrade namesleqembiother namesban2401, lecanemab-irmbahfs/drugs.commonographlicense data us dailymed: lecanemab routes ofadministrationintravenousatc codenonelegal statuslegal status us: ℞-only identifierscas number1260393-98-3drugbankdb14580chemspidernoneunii12pyh0ftu9keggd11678chemical and physical dataformulac6544h10088n1744o2032s46molar mass147181.62 g·mol−1 lecanemab was approved for medical use in the united states in january 2023. medical uses lecanemab is indicated for the treatment of alzheimer's disease. adverse effects lecanemab, and other amyloid targeting therapies, are associated with amyloid-related imaging abnormalities (aria). according to a phase 3 clinical trial (n=1795), lecanemab has been associated with both aria-e (cerebral edema) and aria-h (microhaemorrhages, or small haemorrhages, and hemosiderosis) sub-types. in the lecanemab group, the incidence of aria-e was 12.6% (7.4% in placebo), and the incidence of aria-h was 17.3% (1.7% in placebo). mild to moderate infusion-related reactions can also occur. pharmacology mechanism of action lecanemab is a monoclonal antibody consisting of the humanized version of a mouse antibody, mab158, that recognizes protofibrils and prevents amyloid beta deposition in animal models of alzheimer's disease. history in july 2022, the us food and drug administration (fda) accepted an application for accelerated approval for lecanemab. in september 2022, biogen announced positive results from an ongoing phase iii clinical trial. in november 2022, it was announced that the drug was a success in clinical trials, and exceeded its goal in reaching primary endpoints. the efficacy of lecanemab was evaluated in a double-blind, placebo-controlled, parallel-group, dose-finding study of 856 participants with alzheimer's disease. treatment was initiated in participants whose disease was in the stage of mild cognitive impairment or mild dementia and who had confirmed presence of amyloid beta pathology. participants receiving the treatment showed significant dose- and time-dependent reduction of amyloid beta plaque: those receiving the approved dose of lecanemab, 10 milligrams/kilogram every two weeks, had a statistically significant reduction in brain amyloid plaque from baseline to week 79 compared with those receiving a placebo, who had no reduction of amyloid beta plaque. the fda approved lecanemab in january 2023, via the accelerated approval pathway for the treatment of alzheimer's disease. the fda granted the application for lecanemab fast track, priority review, and breakthrough therapy designations. the approval of leqembi was granted to eisai r&d management co., ltd. society and culture legal status in january 2023, the fda granted accelerated approval for lecanemab. economics lecanemab pricing is us$26,500 per year, with an estimated "per-patient societal value" of us$37,600. however, cost-effectiveness analysis by the institute for clinical and economic review (icer) concluded that a broad range of $8,900 to $21,500 would be appropriate. according to an estimate by the manufacturer, eisai, about 85% of eligible early-alzheimer's patients in the united states are covered by medicare. after reviewing the clinical evidence and considering the treatments’ other potential benefits, disadvantages, and contextual considerations noted above, the california technology assessment forum unanimously concluded that lecanemab at its current pricing represents "low" long term value of money. at lecanemab’s current net price, approximately 5% of the 1.4 million us patients eligible for alzheimer’s disease treatment that targets beta-amyloid could be treated within five years without crossing the icer potential budget impact threshold of $777 million per year. as a result, icer issued an access and affordability alert for lecanemab in the management of alzheimer’s disease. this alert indicates that the health care costs of the treatment might stress the health system in the short term, resulting in the displacement of other services and a rapid increase in insurance costs. names lecanemab is the international nonproprietary name. research lecanemab was jointly developed by the companies eisai and biogen and is in clinical trials for the treatment of alzheimer's disease. it has shown statistically significant but minor progress, with studies suggesting a decrease in cognitive decline in alzheimer's participants compared with a control group given a placebo instead.