Scalp, Eyebrow, and Eyelash Hair Regrowth with Continued Ritlecitinib Treatment Among Patients with Alopecia Areata Without Target Efficacy Response at Week 24: Post Hoc Analysis of the ALLEGRO Phase 2b/3 Study

This post hoc analysis of the ALLEGRO phase 2b/3 study evaluated the efficacy of ritlecitinib, an oral JAK3/TEC inhibitor, in patients with alopecia areata (AA) who did not meet target efficacy response criteria at Week 24. The study included patients aged 2-12 years with at least 50% scalp hair loss. Results showed that among those who did not respond by Week 24, 8-14% achieved a response by Week 28, increasing to 22-34% by Week 48. Similar improvements were observed for eyebrow and eyelash assessments. Ritlecitinib was well tolerated, with common adverse events including upper respiratory tract infection, nasopharyngitis, and headache. The findings suggest that continued ritlecitinib treatment may lead to hair regrowth in patients who initially do not respond.