A phase 2a randomized, placebo-controlled study to evaluate the efficacy and safety of the oral Janus kinase inhibitors ritlecitinib and brepocitinib in alopecia areata: 24-week results.

Abstract Background Alopecia areata (AA) is an autoimmune form of hair loss with limited treatments. Objective To evaluate the efficacy and safety of the Janus kinase inhibitors ritlecitinib and brepocitinib in patients with AA with ≥50% scalp hair loss. Methods Patients were randomized to once-daily ritlecitinib, brepocitinib, or placebo. The primary efficacy endpoint was 24-week change from baseline in Severity of Alopecia Tool (SALT) score; the key secondary efficacy endpoint was proportion of patients achieving 30% improvement in SALT score (SALT30). Results The ritlecitinib, brepocitinib, and placebo groups included 48, 47, and 47 patients, respectively. At week 24, least-squares mean difference from placebo in SALT score change from baseline was 31.1 (95% CI, 18.8-43.5) for ritlecitinib and 49.2 (95% CI, 36.6-61.7) for brepocitinib (P Limitations Only a single dosage regimen of each study drug was included. Conclusion Treatment with ritlecitinib or brepocitinib for 24 weeks was efficacious and generally well tolerated.