Tezepelumab, an anti–thymic stromal lymphopoietin monoclonal antibody, in the treatment of moderate to severe atopic dermatitis: A randomized phase 2a clinical trial

Background: Tezepelumab (AMG 157/MEDI9929), a first-in-class monoclonal antibody, targets thymic stromal lymphopoietin, a cytokine that is implicated in the pathogenesis of atopic dermatitis (AD). Objective: We sought to evaluate the efficacy and safety of tezepelumab in adults with moderate to severe AD. Methods: In this phase 2a study (NCT02525094), 113 patients were randomized 1:1 to subcutaneous tezepelumab 280 mg or placebo every 2 weeks, plus class 3 topical corticosteroids (TCS). The primary endpoint was the week 12 response rate for a ≥50% reduction in the Eczema Area and Severity Index (EASI50). Secondary endpoints including EASI75, Investigator's Global Assessment, SCORAD 50, SCORAD 75, pruritus numeric rating and 5-D itch scales, and exploratory endpoints (including EASI90) were assessed at weeks 12, and 16 (post hoc). Results: A numerically greater percentage of tezepelumab plus TCS-treated patients achieved EASI50 (64.7%) versus placebo plus TCS (48.2%; P =.091). Numerical improvements over placebo were demonstrated for week 12 secondary and exploratory endpoints, with further improvements at week 16. Treatment-emergent adverse events were similar between treatment groups. Limitations: Greater than expected response rates in placebo-treated patients were possibly attributable to TCS. Conclusion: Although not statistically significant, numerical improvements over placebo for all week 12 endpoints were demonstrated, with greater week 16 responses.