A Study to Evaluate the Efficacy and Safety of Subcutaneous Amlitelimab Monotherapy Compared With Placebo in Adult Participants With Severe Alopecia Areata

This is a parallel, Phase 2 multinational, multicenter, randomized, double-blind, placebo-controlled, 3-arm study to investigate the efficacy and safety of subcutaneous (SC) injections of amlitelimab treatment as monotherapy in participants aged 18 years and older with severe alopecia areata (AA). At the end of the double-blind treatment period, all participants will have the option to enter the open-label extension (OLE) period. The study duration will be up to 160 weeks for participants entering the OLE period including a 2-to-4-week screening, a 36-week randomized double-blind period, an optional OLE period (104 weeks) and a 16-week safety follow-up. The open-label extension period is optional and open to all participants who have completed the double-blind treatment period. The total number of visits will be up to 38 visits (or 12 visits for those not entering the OLE study).