A Phase 1, Open‐Label Study of the Pharmacokinetics of Ritlecitinib in Children Aged 6–12 Years With Alopecia Areata
Mercedes E. Gonzalez, John Browning, Stacy Smith, Anna Plotka, Jing “Daisy” Zhu, Shyam Parvatini, Yeamin Huh, Robert WolkABSTRACT
Background
Alopecia areata (AA) is an autoimmune disease characterized by hair loss that can negatively impact quality of life. AA has a significant pediatric prevalence; however, no systemic treatments are approved for AA in patients aged < 12 years. Ritlecitinib, a JAK3/TEC family kinase inhibitor, is approved to treat adults and adolescents with severe AA aged ≥ 12 years. This study evaluated ritlecitinib pharmacokinetic (PK) parameters and safety in pediatric patients with AA aged 6 to < 12 years.
Methods
In this single‐group, uncontrolled, open‐label study, participants received ritlecitinib 20 mg once daily for 7 days. PK parameters of ritlecitinib on Day 7 were measured and summarized descriptively. Safety outcomes, including incidence of adverse events (AEs), were evaluated.
Results
Fifteen participants were enrolled and 14 (93.3%) completed the study. The median time to maximum concentration (Tmax) for plasma concentrations of ritlecitinib on Day 7 was ~0.5 h. The mean half‐life of ritlecitinib was ~1.19 h. Geometric means (% coefficient of variation) for area under the curve from 0 to 24 h (AUC24) and maximum concentration (Cmax) were 437.5 ng·h/mL (30%) and 208.7 ng/mL (38%), respectively. Four AEs were experienced by 3 participants, with 1 AE of urticaria resulting in permanent discontinuation. No severe AEs, serious AEs, or clinically meaningful laboratory abnormalities were reported.
Conclusions
Ritlecitinib PK parameters in pediatric patients were successfully characterized in the present study. Ritlecitinib 20 mg once daily was generally well tolerated in pediatric patients with AA.
Trial Registration
NCT05650333