Efficacy and safety of ritlecitinib in Asian patients with alopecia areata: A subgroup analysis of the ALLEGRO phase 2b/3 trial

Abstract

This subgroup analysis of the ALLEGRO phase 2b/3 study (NCT3732807) assessed the efficacy and safety of multiple doses of ritlecitinib, an oral JAK3/TEC family kinase inhibitor, in Asian patients with alopecia areata (AA). Patients aged ≥12 years with AA and ≥50% scalp hair loss received once-daily ritlecitinib 50 or 30 mg (with or without 4-week 200-mg loading dose ["200/50" or "200/30"]) or 10 mg or placebo for 24 weeks, followed by a 24-week extension, in which patients initially assigned to placebo switched to 200/50 or 50 mg. In this subgroup analysis, Asian patients with response based on achieving a Severity of Alopecia Tool (SALT) score ≤20, SALT ≤10, ≥2-grade improvement or normal score on the eyebrow assessment (EBA) scale, and ≥2-grade improvement or normal score on the eyelash assessment (ELA) scale were evaluated through week 48. Safety was monitored throughout. In total, 186 Asian patients were randomized to ritlecitinib 200/50 mg (n = 33), 200/30 mg (n = 28), 50 mg (n = 43), 30 mg (n = 34), 10 mg (n = 17), placebo to 200/50 mg (n = 14), or placebo to 50 mg (n = 17). The proportions of patients treated with ritlecitinib ≥30 mg achieving a SALT score ≤20 response were 9.1%-36.4% at week 24 vs 0% for the 10-mg group and 3.2% for placebo. At week 48, 26.5%-55.6% of patients treated with ritlecitinib ≥30 mg achieved a SALT ≤20 response. At week 48, the proportions of patients treated with ritlecitinib ≥30 mg with EBA response were 41.9%-71.1% and with ELA response were 40.7%-57.9%. The most common adverse events were nasopharyngitis, folliculitis, upper respiratory tract infection, and urticaria. No serious or opportunistic infections, major adverse cardiovascular events, thromboembolic events, malignancies, or deaths were reported. Ritlecitinib demonstrated clinical efficacy and acceptable safety over 48 weeks in Asian patients ≥12 years with AA and ≥50% hair loss. Results for the Asian subpopulation were consistent with the overall population in the ALLEGRO-2b/3 study.

Keywords: ALLEGRO; SALT; Severity of Alopecia Tool; alopecia areata; ritlecitinib.

FIGURE 1

Proportion of Asian patients from the ALLEGRO‐2b/3 study with response based on (a) Severity of Alopecia Tool (SALT) score ≤20 and (b) SALT score ≤10 at week 24. CI, confidence interval; n, number of patients with SALT score ≤20 or ≤10 response; N1, number of patients with valid data at week 24 (nonresponse for missing due to reasons unrelated to COVID‐19, excludes missing due to COVID‐19). Percentage based on N1.

FIGURE 2

Proportion of Asian patients from the ALLEGRO‐2b/3 study with response based on (a) Severity of Alopecia Tool (SALT) score ≤20 and (b) SALT score ≤10 over time to week 48. CI, confidence interval; QD, once daily.

FIGURE 3

Change from baseline in Severity of Alopecia Tool score over time to week 48 in Asian patients from the ALLEGRO‐2b/3 study. CI, confidence interval; QD, once daily.

FIGURE 4

Proportions of Asian patients from the ALLEGRO‐2b/3 study with (a) eyebrow response (≥2‐grade improvement or normal eyebrow assessment [EBA] score) and (b) eyelash response (≥2‐grade improvement or normal eyelash assessment [ELA] score) from baseline to week 48. CI, confidence interval; QD, once daily.

FIGURE 5

Proportions of Asian patients from the ALLEGRO‐2b/3 study with Patient Global Impression of Change (PGI‐C) response^a at weeks 24 and 48. ^aPGI‐C response is defined as “moderately improved” or “greatly improved.” CI, confidence interval; N, number of patients with PGI‐C response; N1, number of patients with valid data at the analysis visit (nonresponse for missing due to reasons unrelated to COVID‐19, excludes missing due to COVID‐19); PBO, placebo. Percentage based on N1.

FIGURE 6

Representative photographs of an Asian patient from the subgroup analysis of the ALLEGRO‐2b/3 study with hair regrowth response to ritlecitinib 50 mg. SALT, Severity of Alopecia Tool.