Dupilumab in adolescents with uncontrolled moderate-to-severe atopic dermatitis: results from a phase IIa open-label trial and subsequent phase III open-label extension.

BackgroundDupilumab (monoclonal antibody inhibiting IL-4/IL-13 signalling) is approved for use in adolescents aged ≥ 12 years with inadequately controlled moderate-to-severe atopic dermatitis (AD). Dupilumab significantly improved AD signs/symptoms in a 16-week, randomised, placebo-controlled phase III trial in adolescents (NCT03054428).ObjectivesTo characterize the pharmacokinetics of dupilumab, and long-term safety and efficacy in adolescents.MethodsThis was a global, multicentre, phase IIa, open-label, ascending-dose, sequential cohort study with a phase III open-label extension (OLE) in adolescents with moderate-to-severe AD. In the phase IIa study, patients received one dupilumab dose (2 mg kg-1 or 4 mg kg-1 ) and 8 weeks of pharmacokinetic sampling. Thereafter, patients received the same dose weekly for 4 weeks, with 8-week safety follow-up. Patients then enrolled in the OLE, continuing 2 mg kg-1 or 4 mg kg-1 dupilumab weekly. Primary end points were dupilumab concentration-time profile and incidence of treatment-emergent adverse events (TEAEs). Secondary outcomes included Eczema Area and Severity Index (EASI).ResultsForty adolescents received dupilumab in the phase IIa study; 36 enrolled in the OLE. Dupilumab showed nonlinear, target-mediated pharmacokinetics. Mean ± SD trough dupilumab concentrations in serum at week 48 (OLE) were 74 ± 19 mg L-1 and 161 ± 60 mg L-1 for 2 mg kg-1 and 4 mg kg-1 , respectively. Dupilumab was well tolerated over 52 weeks; the most common TEAEs were nasopharyngitis (week 52: 41% [2 mg kg-1 ], 47% [4 mg kg-1 ]) and AD exacerbation (29%, 42%). After one dupilumab dose in the phase IIa study, EASI improved from baseline to week 2 [mean ± SD reduction -34% ± 20% (2 mg kg-1 ) and -51% ± 29% (4 mg kg-1 )]. With continuing treatment, EASI scores improved further [week 52: -85% ± 12% (2 mg kg-1 ) and -84% ± 20% (4 mg kg-1 )].ConclusionsIn adolescents with moderate-to-severe AD, dupilumab's pharmacokinetic profile was similar to that in a