Leqembi Side Effects

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: Amyloid Related Imaging Abnormalities [see Warnings and Precautions ( 5.1 )] Hypersensitivity Reactions [see Warnings and Precautions ( 5.2 )] Infusion-Related Reactions [see Warnings and Precautions ( 5.3 )] Most common adverse reactions (at approximately 10% and higher incidence compared to placebo): infusion-related reactions, amyloid related imaging abnormality-microhemorrhages, amyloid related imaging abnormality-edema/effusion, and headache.

( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Eisai Inc.

at 1-888-274-2378 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Clinical Trials with Intravenous Administration The safety of LEQEMBI has been evaluated in 2090 patients who received at least one dose of LEQEMBI by intravenous infusion.

In Studies 1 and 2 in patients with Alzheimer’s disease, 1059 patients received LEQEMBI 10 mg/kg every two weeks by intravenous infusion [see Clinical Studies ( 14 )] .

Of these 1059 patients, 50% were female, 79% were White, 15% were Asian, 12% were of Hispanic or Latino ethnicity, and 2% were Black.

The mean age at study entry was 72 years (range from 50 to 90 years).

In the combined double-blind, placebo-controlled period and long-term extension period of Studies 1 and 2, 1604 patients received LEQEMBI for at least 6 months, 1261 patients for at least 12 months, and 965 patients for 18 months.

In the double-blind, placebo-controlled period in Study 1, patients stopped study treatment because of an adverse reaction in 15% of patients treated with LEQEMBI, compared to 6% patients on placebo;