Efficacy and Safety of Ixekizumab Versus Adalimumab in Biologic-naïve Patients With Active Psoriatic Arthritis and Moderate-to-severe Psoriasis: 52-week Results From the Randomized SPIRIT-H2H Trial

INTRODUCTION: The randomized, open-label, assessor-blinded, parallel-group SPIRIT-H2H trial (NCT03151551) demonstrated superiority of ixekizumab over adalimumab in simultaneously achieving improvement in joint symptoms (American College of Rheumatology [ACR]50) and skin clearance (Psoriasis Area and Severity Index [PASI]100) in biologic-naïve patients with active psoriatic arthritis (PsA) and plaque psoriasis (PsO) at Week (W) 24. Higher efficacy of ixekizumab versus adalimumab was maintained through W52.

OBJECTIVES: This analysis investigated efficacy and safety of ixekizumab and adalimumab in the subgroup of patients with PsA and moderate-to-severe PsO through W52.

METHODS: Efficacy and safety outcomes were analyzed in patients with PsA and moderate-to-severe PsO (PASI ≥ 12, Body Surface Area ≥ 10%, static Physician Global Assessment ≥ 3) through W52. Categorical and continuous outcomes were analyzed using logistic regression models and mixed model for repeated measures, respectively.

RESULTS: More ixekizumab-versus adalimumab-treated patients simultaneously achieved PASI100 and ACR50 at W24 (40.8% versus 17.6%, P = 0.015) and W52 (38.8% versus 17.6%, P = 0.026). Likewise, more ixekizumab-versus adalimumab-treated patients achieved PASI100 (59.2% versus 25.5%, P = 0.001) and PASI90 (81.6% versus 60.8%, P = 0.028) through W52, and nail PsO clearance at W24. Joint symptom improvements were comparable between groups. No new safety findings were reported.

CONCLUSIONS: Ixekizumab had higher efficacy than adalimumab in simultaneous achievement of ACR50 and PASI100 at W24 and W52 in patients with PsA and moderate-to-severe PsO. Ixekizumab-treated patients showed higher response rates for nail PsO clearance and for reporting minimal or no impact on quality of life at W24.