Subcutaneous Dose Selection of Lecanemab for Treatment of Subjects with Early Alzheimer’s Disease (EAD)

Lecanemab is a humanized IgG1 monoclonal antibody that preferentially targets soluble aggregated Aβ species (protofibrils) with activity at insoluble fibrils. Lecanemab 10 mg/kg IV biweekly dose (10BW) is being evaluated in the Clarity AD Phase 3 study in Early AD. A Phase 1 study was conducted to assess the absolute bioavailability (BA) of subcutaneous (SC) administration relative to IV infusion. Modeling and simulation analysis was conducted to demonstrate equivalence of a fixed weekly SC dose to body weight‐based IV 10BW dose with regard to lecanemab exposure, safety and efficacy.