Sustained hair regrowth with continued ritlecitinib treatment through Week 48 in patients with alopecia areata with or without early target responses: post hoc analysis of the ALLEGRO phase 2b/3 trial

Background: Few treatments for alopecia areata (AA) have demonstrated sustained efficacy.

Objective: Evaluate the efficacy and safety of continued ritlecitinib treatment to Week 48 in patients with AA with or without target efficacy responses at Week 24.

Methods: Patients aged ≥12 years received daily ritlecitinib (± 4-week loading dose): 200/50 mg, 200/30 mg, 50 mg, or 30 mg. Patients with clinical response at Week 24, based on a Severity of Alopecia Tool (SALT) score ≤20 and ≤10 were evaluated for sustained response through Week 48. Nonresponders at Week 24 were assessed for response through Week 48.

Results: Among ritlecitinib-treated patients with SALT score ≤20 and ≤10 responses at Week 24, ≥85% and ≥68%, respectively, sustained these responses through Week 48. Of those with SALT score >20 at Week 24, 22%-34% achieved SALT score ≤20 at Week 48. Of those with a SALT score >10 at Week 24, 20%-26% achieved SALT score ≤10 at Week 48. Safety was similar across subgroups.

Limitations: Small sample size.

Conclusion: Hair regrowth was sustained through Week 48 in patients with response at Week 24. Up to one-third of patients who did not meet target efficacy at Week 24 achieved response with continued ritlecitinib treatment.