Targeting IL-22RA1 with temtokibart: A novel approach in atopic dermatitis: Phase 2a monotherapy study results

Background: Atopic dermatitis (AD) is a chronic inflammatory skin disease in which increased IL-22 expression contributes to epidermal hyperplasia and barrier defects. Temtokibart is a monoclonal antibody targeting IL-22RA1 (IL-22 Receptor subunit alpha-1), blocking the signaling of IL-22 and potentially also of IL-20 and IL-24.

Objective: We evaluated the efficacy and safety of temtokibart in adults with moderate-to-severe AD.

Methods: In this phase 2a study (NCT04922021), 58 adults were randomized 1:1 to subcutaneous temtokibart 450 mg or placebo every 2 weeks for 16 weeks, with an additional dose (450 mg) at week 1, followed by additional 16 weeks of safety follow-up. The primary end point was change in Eczema Area Severity Index (EASI) from baseline to week 16. Biomarkers in serum, including IL-22, were analyzed as an exploratory end point.

Results: Mean change in EASI from baseline to week 16 was significantly greater for temtokibart compared to placebo (-15.3 vs -3.5; P = .003), corresponding to 65.4% and 19.7% improvement for temtokibart and placebo groups, respectively. At week 16, greater proportions of patients receiving temtokibart relative to placebo obtained EASI-75 (41.6% vs 13.7%; P = .011), EASI-90 (30.8% vs 3.5%; P = .003), and EASI-100 (20.9% vs 0%; P = .006). Treatment with temtokibart was well tolerated, and no safety signals were observed. Further, temtokibart treatment was associated with a general reduction of systemic inflammatory proteins.

Conclusions: This proof-of-concept study demonstrates that targeting the IL-22 pathway with temtokibart is clinically effective with a favorable safety profile.