Janus Kinase Inhibitors for Alopecia Areata

Janus kinase (JAK) inhibitors have significantly advanced the treatment of moderate-to-severe alopecia areata (AA), a condition that has been difficult to treat historically. The approval of baricitinib and ritlecitinib, with deuruxolitinib nearing approval, highlights this progress. Phase 3 clinical trials demonstrated that baricitinib resulted in ≤20% scalp hair loss in 39% and 23% of patients at 4 mg and 2 mg doses, respectively, over 36 weeks. Ritlecitinib showed similar results in 23% of patients at 50 mg over 24 weeks, increasing to 40% over 48 weeks, while deuruxolitinib showed 30%-42% efficacy over 24 weeks. These results emphasize the potential of JAK inhibitors in managing AA, although topical JAK inhibitors have not been effective for moderate-to-severe cases.