Patterns of clinical response in patients with alopecia areata treated with ritlecitinib in the ALLEGRO clinical...

Ritlecitinib, an oral JAK3/TEC family kinase inhibitor, demonstrated efficacy over 48 weeks in patients with alopecia areata (AA) in the ALLEGRO phase 2b/3 study.

This post hoc analysis evaluated individual Severity of Alopecia Tool (SALT) score trajectories in patients who received ritlecitinib 50 mg and rolled over from Phase 2b/3 into the ongoing, open-label, Phase 3 ALLEGRO-LT study to describe long-term response patterns and associated baseline disease characteristics.

Patients aged ≥12 years with ≥50% scalp hair loss received ritlecitinib 50 mg once daily in both studies. SALT score trajectories from baseline to Month 24 were used to categorise patients as early (SALT score ≤20 at Week 24 and Months 12 and 24), middle (≤20 at Months 12 and 24) or late responders (≤20 by Month 24) or as partial responders (maintained 30% improvement), relapsers (achieved but did not maintain 30% improvement) or non-responders (did not achieve 30% improvement). The proportions of patients achieving sustained response (achieved and maintained SALT score ≤20 at all subsequent available time points through Month 24) and complete response (SALT score 0 at ≥1 time point through Month 24) were evaluated. Multivariable logistic regression assessed variables associated with response.

Of 191 patients treated with ritlecitinib 50 mg, 87 (45.5%) were responders (SALT score ≤20), 24 (12.6%) were partial responders, 24 (12.6%) were relapsers and 56 (29.3%) were non-responders. Of 87 patients categorised as responders, 81 (93.1%) sustained their clinical response and 47 (46.0%) achieved complete response. Factors associated with treatment response included female sex and less extensive and shorter duration of hair loss.

Approximately 45% of patients were SALT score responders, with up to 11% requiring >1 year of ritlecitinib treatment to achieve response, highlighting the importance of extended treatment duration.

ALLEGRO phase 2b/3 study (NCT03732807); ALLEGRO-LT study (NCT04006457).