SAN FRANCISCO, CA—Patients with active psoriatic arthritis who were biologic disease-modifying antirheumatic drug (bDMARD)-naive had significantly improved quality of life, physical function, and work productivity following treatment with ixekizumab, investigators reported at the 2015 ACR/ARHP Annual Meeting.

The Phase 3 trial investigated the effects of ixekizumab, an IgG4 monoclonal antibody, in 417 patients with active psoriatic arthritis.

Alice B. Gottlieb, MD, PhD, the Harvey B. Ansell Professor of Dermatology at Tufts Medical Center, Boston, MA, and colleagues randomly assigned patients to receive up to 24 weeks of placebo (n=106); adalimumab 40mg once every two weeks (n=101) as the active control; or ixekizumab 80mg every four weeks (n=107) or every two weeks (n=103) following a 160mg starting dose at Week 0.

At Week 12, patients treated with either ixekizumab 80mg every 4 weeks or every 2 weeks reported “significantly greater improvements compared to placebo” in the Health Assessment Questionnaire-Disability Index (HAQ-DI), the Short Form-36 Health Survey Physical Component Score (SF-36 PCS), the European Quality of Life 5 Dimensions Visual Analog  Scale (EQ-5D VAS), and the Work Productivity and Activity Impairment-Specific Health Problem (WPAI-SHP) (all components, except Absenteeism).

“These improvements were maintained through Week 24 for all treatment groups,” Dr. Gottlieb noted.

“Additionally, at Weeks 12 and 24, the percentage of patients with a baseline HAQ-DI score ≥0.35 achieving minimally clinically important difference (MCID) for HAQ-DI (improvement from baseline in HAQ-DI ≥0.35) was significantly greater in both ixekizumab treatment arms compared to placebo.”

At Week 12, compared with 29.3% for placebo, the HAQ-DI MCID was 49.4% for adalimumab 40mg (P<0.01), 49.0% for ixekizumab 80mg every 4 weeks (P<0.01), and 64.4% for ixekizumab 80mg every 2 weeks (P<0.001).

At Week 24, these rates were 26.1% for placebo, 49.4% for adalimumab 40mg (P<0.001), 49.4% for ixekizumab 80mg every 4 weeks (P<0.001), and 57.8% for ixekizumab 80mg every 2 weeks (P<0.001).

“Reduced impairment of activities outside of work was significantly greater in patients treated with ixekizumab compared to placebo,” Dr. Gottlieb said. “Rapid and significant improvements were seen in functional disability in patients treated with ixekizumab compared to placebo as evidenced by changes in HAQ-DI scores.”