Efficacy and Safety of Subcutaneous Dupilumab for the Treatment of Adult Participants With Chronic Pruritus of Unknown Origin (CPUO) (LIBERTY-CPUO-CHIC)

The main objective of the study is to assess efficacy and safety of dupilumab given up to 24 weeks in adults with CPUO. This is a master protocol which includes 2 parallel-treatment, double-blind, 2- arm Phase 3 staggered studies of similar design (Study A and Study B) in male and female participants aged 18 to 90 years with CPUO. Study B design was to be adapted based on the results of Study A. For both Study A and B, after an up-to-4-week screening period, participants with severe pruritus (worst-itch numerical rating scale \[WI-NRS ≥7) will enter a 4-week run-in period and will be treated with a non-sedative antihistamine and an emollient (moisturizer). Participants with severe pruritus (WI-NRS ≥7) at baseline will be randomized (1:1) to be treated for 24 weeks with either dupilumab or matching placebo in addition to their non-sedative antihistamine and emollient regimen. The treatment period for both study A and B will be followed by a 12-week follow-up period.