Open Label, Drug-Drug Interaction (DDI) Study of Dupilumab (REGN668/SAR231893) in Patients With Moderate to Severe Atopic Dermatitis (AD)

This is an open-label, single-sequence DDI study designed to examine the effects of dupilumab on the pharmacokinetics of selected cytochrome P450 substrates in adult patients with moderate to severe AD. The study consists of a screening period (day -35 to -2), study period 1 (day -1 to 7), study period 2 (day 8 to 50), and a follow-up period (day 51 to 135 \[end of study\]). Following completion of study period 2 (Day 50), patients will be given the option to enroll into the Open-Label Extension (OLE) study R668-AD-1225. Patients who decline will be followed for the next 12 weeks (Day 135).