Ixekizumab provides improvements through 52 weeks in physical function, quality of life, and work productivity in biologic diseasemodifying antirheumatic drug (bDMARD) naive patients with active psoriatic arthritis (PsA)

Introduction: Approximately 6% to 42% of patients with psoriasis suffer from comorbid PsA, a progressive and destructive auto‐inflammatory disease. PsA has a significant negative impact on patients' physical function, quality of life, and work productivity; therefore, improving patient‐reported outcomes (PROs) is critical in enhancing the lives of patients with PsA. Patients treated with ixekizumab (IXE), a high affinity monoclonal antibody that selectively targets interleukin‐17A, reported significant improvements in PROs during the 24‐week, placebo (PBO)‐controlled period of the Phase 3 SPIRIT‐P1 trial. Objectives: To evaluate whether an effect of IXE on improvement of PROs is also observed at week 52 in SPIRIT‐P1. Materials and Methods: 417 bDMARD‐naive patients with active PsA were randomly assigned to subcutaneous administration of 80 mg IXE every 4 weeks (Q4W) or 2 weeks (Q2W), each with a 160 mg starting dose at week 0, adalimumab (ADA) 40 mg Q2W (active control), or PBO in the Double‐Blind Treatment Period (weeks 0 through 24). 381 patients continued into the Extension Period (EP; weeks 24 through 52). PBO‐ and ADA‐ treated patients were randomly re‐assigned (to 80 mg IXEQ4W or IXEQ2W at week 24; ADA‐treated patients started IXE after an 8‐week wash‐out period at week 32. Analyses for the EP were conducted on the EP Population, patients who received at least 1 dose of study drug during the EP. Missing values were imputed by nonresponder imputation for categorical data and modified baseline observation carried forward for continuous data. Results: Physician‐assessed clinical efficacy was shown by achievement of American College of Rheumatology (ACR) 20 response by 69% of patients receiving IXE for 52 weeks. Patients treated with IXE for 52 weeks reported improvements (mean change from baseline [standard deviation]) in Health Assessment Questionnaire ‐ Disability Index (HAQ‐DI; IXEQ4W = ‐0.53 [0.56], IXEQ2W = ‐0.55 [0.52]); Short Form‐36 Health Survey Physical Component Summary (IXEQ4W = 9.5 [9.5], IXEQ2W = 9.2 [9.4]); itch numeric rating scale (IXEQ4W = ‐3.3 [2.51], IXEQ2W = ‐3.5 [3.06]); and Work Productivity and Activity Impairment‐Specific Health Problem (presenteeism: IXEQ4W = ‐23.6 [27.0], IXEQ2W = ‐25.4 [21.3]; work productivity: IXEQ4W = ‐25.3 [28.0], IXEQ2W = ‐24.9 [22.9]; and activity impairment: IXEQ4W = ‐26.2 [26.9], IXEQ2W = ‐29.1 [24.1]) that were similar to improvements reported at week 24 (see Introduction). The percentages of patients with improvement from baseline HAQ‐DI score >0.35 achieving minimally clinically important difference for HAQ‐DI were similar at week 52 (IXEQ4W = 57.1%, IXEQ2W = 57.1%) to the percentages observed at week 24. Conclusion: IXE provides sustained improvement through 52 weeks in physical function, quality of life, and work productivity in bDMARD‐naive patients with active PsA.