Alopecia areata is an autoimmune condition mediated by inflammatory cytokine cascades around hair follicles, frequently causing severe scalp and body hair loss that impacts psychological well-being. In two multinational double-blind Phase 3 randomized clinical trials (UP-AA1 and UP-AA2; N = 1,399) published in JAMA Dermatology, adolescents and adults with severe alopecia areata were randomized to once-daily upadacitinib (15 mg or 30 mg) or placebo. Both upadacitinib doses met primary endpoints at week 24, achieving substantial rates of scalp hair coverage (Severity of Alopecia Tool score ≤20) alongside significant eyebrow and eyelash regrowth compared with placebo.

Treatment was generally well tolerated, with safety findings consistent with the established profile of JAK inhibitors. These Phase 3 trials confirm oral upadacitinib as a highly efficacious systemic therapy for reversing…