Abrocitinib efficacy and safety in moderate-to-severe atopic dermatitis by race, ethnicity, and Fitzpatrick skin type

Background: Response to abrocitinib treatment for moderate-to-severe atopic dermatitis (AD) has not been evaluated across racial and ethnic subpopulations. Objective: To assess the efficacy and safety of abrocitinib on the basis of patient race, ethnicity, and Fitzpatrick skin type (FST). Methods: Data were pooled post hoc from patients treated with abrocitinib 200 mg, 100 mg, or placebo in 3 monotherapy trials (NCT02780167, NCT03349060, and NCT03575871). Race and ethnicity were self-reported; FST was determined by study investigators. Evaluations through Week 12 include the following: (1) Investigator's Global Assessment of clear or almost-clear skin; (2) greater than or equal to 75% improvement in Eczema Area and Severity Index or SCORing AD; (3) a greater-than-or-equal-to 4-point improvement in Peak Pruritus Numerical Rating Scale score; (4) least squares mean changes in Dermatology Life Quality Index and Patient-Oriented Eczema Measure scores; and (5) treatment-emergent adverse events. Results: The sample comprised 628 White, 204 Asian, and 83 Black patients; 37 were Hispanic or Latino; 624 had FST I to III and 320 had FST IV to VI. Treatment with either abrocitinib dose was associated with greater proportions of patients achieving Investigator's Global Assessment of clear or almost-clear skin, ≥ 75% improvement in Eczema Area and Severity Index, ≥ 75% improvement in SCORing AD, and a ≥ 4-point improvement in Peak Pruritus Numerical Rating Scale, or greater score changes from baseline in Dermatology Life Quality Index and Patient-Oriented Eczema Measure vs placebo regardless of race, ethnicity, or FST. Dose-response was most prominent in White patients. In Black patients, the effects of the 2 doses were similar. Treatment-emergent adverse events were more common in White and Black than in Asian patients. Conclusion: Abrocitinib was more efficacious than placebo across the racial and ethnic groups and ranges of phototypes analyzed. Studies with increased representation of populations of color are warranted to elucidate potential variations in response across diverse populations. Trial Registration: Clinicaltrials.gov Identifier: NCT02780167 (phase 2b), NCT03349060 (phase 3 MONO-1), and NCT03575871 (phase 3 MONO-2).