667 - Maintenance of efficacy and safety with nemolizumab at week 48: results from two global phase 3 pivotal studies (ARCADIA-1 and ARCADIA-2) in patients with moderate-to-severe atopic dermatitis

Abstract Background Atopic dermatitis (AD) is a common, chronic, and flaring itchy inflammatory skin disease requiring long-term treatment. Nemolizumab significantly improved skin lesions, itch, and sleep through Week (W) 16 in two global phase 3 studies (ARCADIA-1 [NCT03985943] and ARCADIA-2 [NCT03989349]) in adolescents and adults with moderate-to-severe AD.1 Introduction/Background To evaluate the efficacy and the safety of maintenance treatment with nemolizumab with background topical therapy for up to 32 weeks in patients (≥12 years) with moderate-to-severe atopic dermatitis Methods This analysis pooled 32-week maintenance data from two double-blind, placebo controlled, phase 3 studies (N=507) in moderate-to-severe AD. Clinical responders (IGA 0/1 [clear/almost-clear] or EASI-75 [75% improvement in EASI score]) to nemolizumab at W16 were re-randomized (1:1:1) to receive nemolizumab 30mg every 4 weeks (Q4W), nemolizumab 30mg Q8W, or placebo (nemolizumab withdrawal) Q4W subcutaneously for further 32 weeks in combination with topical corticosteroids of low/medium potency and/or topical calcineurin inhibitors. Safety was assessed throughout the study. Results At W48, the proportion of patients who maintained IGA success (defined as IGA score of 0 [clear] or 1 [almost clear] and a ≥2-point improvement from baseline) was 61.5% (nemolizumab-Q4W), 60.4% (nemolizumab-Q8W), and 49.7% (placebo); EASI-75 was maintained in 76.3% (nemolizumab-Q4W), 75.7% (nemolizumab-Q8W), and 63.9% (placebo); and itch response (≥4 points improvement in weekly average PPNRS) was achieved in 76.2% (nemolizumab-Q4W), 59.7% (nemolizumab-Q8W), and 41.0% (placebo). Similarly, response in sleep and quality of life was well maintained at W48. The safety profile was consistent across treatment arms; most treatment-emergent adverse events were non-serious and mild/moderate in intensity. Conclusions Among patients with clinical responses in skin lesions at W16, the majority maintained skin and itch responses at W48 with nemolizumab Q4W/Q8W. Nemolizumab was well-tolerated up to W48, and no safety signals were identified.