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FDA approves Pfizer's JAK inhibitor for adolescents with alopecia areata hair loss
Nature Medicine explores the latest translational and clinical research news, with a newly approved JAK and TEC inhibitor for the autoimmune disease alopecia areata.
The US Food and Drug Administration (FDA) has approved ritlecitinib, an inhibitor of JAK3 and the TEC family, from Pfizer, for adults and children 12 years of age and older who suffer from severe alopecia areata. The positive decision is based on the results of the ALLEGRO phase 2b/3 trial, which enrolled 718 adolescents and adults who had scalp hair loss of 50% or more. The trial’s primary endpoint was achievement, at week 24, of a score of 20 or less on the absolute severity of alopecia tool (SALT), which runs from 0 to 100. ALLEGRO included four different dosing regimens, all of which met the primary endpoint (a fifth group that received a low dose of 10 mg was analyzed only for pharmacokinetics and safety and was not included in the comparison with placebo). In the highest-dose arm of the trial, 31% of patients had a SALT score of 20 or less, versus 2% in the placebo arm.