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 have demonstrated sustained efficacy.

Objective: Evaluate the efficacy and safety of continued ritlecitinib treatment to week 48 in patients with alopecia areata 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 a SALT score >20 at week 24, 22% to 34% achieved a SALT score ≤20 at week 48. Of those with a SALT score >10 at week 24, 20% to 26% achieved a 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.