Efficacy of baricitinib 4 mg in patients with moderate-to-severe atopic dermatitis previously treated with systemic therapy

Background: The Janus kinase (JAK)1/JAK2 inhibitor baricitinib in combination with topical corticosteroids (TCS) improved moderate-to-severe atopic dermatitis (AD) in the phase 3 BREEZE-AD7 trial. Patients with previous systemic therapy may have more severe, treatment-resistant disease. Objectives: To assess the efficacy of baricitinib 4 mg in adults with moderate-to-severe AD with and without previous use of systemic therapy. Methods: Patients were randomized 1:1:1 to TCS plus once-daily oral placebo, 2 mg baricitinib or 4 mg baricitinib for 16 weeks. Outcomes were assessed in patients treated with baricitinib 4 mg with and without previous use of systemic therapy (N = 68, N = 43) versus placebo (N = 75, N = 34). Prior use of systemic therapy was defined as treatment of AD with oral corticosteroids, immunosuppressants or biologics. Endpoints included the proportions of patients achieving a vIGA-AD (R) score 0 or 1 with >2-point improvement from baseline, 75% improvement in the Eczema area and severity index score (EASI75), >= 4-point improvement on the Itch numeric rating scale (NRS) and >= 4-point improvement in the dermatology life quality index (DLQI). Logistic regression was used to evaluate consistent treatment effects across subgroups. Results: At Week 16, among patients with and without previous use of systemics treated with baricitinib 4 mg versus placebo, respectively, vIGA-AD score (0, 1) was achieved in 27.9% and 34.9% versus 13.3% and 17.6%, EASI75 was met in 47.1% and 48.8% versus 22.7% and 23.5%, Itch NRS >= 4-point improvement was observed in 44.4% and 43.2% versus 14.1% and 33.3% and DLQI >= 4-point improvement was seen in 75.8% and 69.2% versus 52.1% and 54.8%. Consistent treatment effects were observed between patients with or without prior use of systemics (treatment-by-subgroup interactions p = 0.085 for Itch NRS, p > 0.1 for all others). Conclusions: Baricitinib 4 mg significantly reduced disease severity in AD compared to placebo regardless of prior systemic therapy.