Efficacy and safety of baricitinib versus azathioprine, both combined with topical corticosteroids, in patients with moderate-to-severe atopic dermatitis: a single-centre randomized open-label trial.

Abstract

Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease that can be difficult to manage in moderate-to-severe cases. Baricitinib (a Janus kinase 1/2 inhibitor) and azathioprine (a traditional immunosuppressant) are both used in the systemic treatment of AD. To compare the efficacy and safety of baricitinib vs. azathioprine, both combined with topical corticosteroids (TCS), in adults with moderate-to-severe AD. In this single-centre open-label randomized head-to-head trial (NCT05969730), 40 adults with moderate-to-severe AD were randomly assigned 1 : 1 to receive baricitinib (4 mg daily) or azathioprine (1.52.5 mg kg-1 daily), both with TCS and urea 10% cream, for 12 weeks. The primary endpoint was the proportion of patients achieving ≥ 75% reduction in Eczema Area and Severity Index (EASI 75) at week 12. At week 12, 65% (n = 13/20) of patients in the baricitinib + TCS group achieved EASI 75 vs. 15% (n = 3/20) in the azathioprine + TCS group [difference 50%, 95% confidence interval (CI) 23.9-76.1; P = 0.002]. The baseline-adjusted post-treatment mean (SD) EASI scores were 5.60 (7.51) for baricitinib and 12.61 (7.51) for azathioprine (difference -7.01, 95% CI -11.86 to -2.17; P = 0.006), with a large effect size (Cohen's d = -0.93). A ≥ 75% decrease in SCORing Atopic Dermatitis score (SCORAD 75) was achieved by 55% (n = 11/20) in the baricitinib + TCS group vs. 15% (n = 3/20) in the azathioprine group (difference 40%, 95% CI 13.2-66.8; P = 0.01). Improvements in validated Investigator's Global Assessment for AD, Itch Numeric Rating Scale (NRS), Skin Pain NRS, Patient-Oriented Eczema Measure, Dermatology Life Quality Index and Hospital Anxiety and Depression Scale scores were found in both groups, with a trend favouring baricitinib, although the differences between groups were not statistically significant. Both treatments were well tolerated, with no serious adverse events or discontinuations recorded. Baricitinib + TCS demonstrated superior efficacy to azathioprine + TCS in adults with moderate-to-severe AD, both with a well-tolerated safety profile at 12 weeks.