Efficacy of ixekizumab compared to etanercept and placebo in patients with moderate-to-severe plaque psoriasis and non-pustular palmoplantar involvement: results from three phase 3 trials (UNCOVER-1, UNCOVER-2 and UNCOVER-3)

Background: Palmoplantar psoriasis has significant physical and emotional impact on patients and can be difficult to treat.

Objective: To evaluate the efficacy of ixekizumab in the treatment of patients with moderate-to-severe plaque psoriasis and moderate-to-severe non-pustular palmoplantar involvement.

Methods: In three phase 3, double-blind, placebo-controlled trials, patients with moderate-to-severe non-pustular plaque psoriasis [UNCOVER-1 (N = 1296), UNCOVER-2 (N = 1224), UNCOVER-3 (N = 1346)] were randomized to subcutaneous 80 mg ixekizumab every 2 or 4 weeks (Q2W, Q4W), after a 160-mg starting dose, or placebo through week 12. Additional UNCOVER-2 and UNCOVER-3 cohorts were randomized to 50 mg etanercept biweekly. Patients entering the open-label long-term extension (UNCOVER-3) received ixekizumab Q4W weeks 12-60. Moderate-to-severe palmoplantar involvement was defined as Palmoplantar Psoriasis Area and Severity Index (PPASI) ≥8.

Results: Twenty-eight percent of UNCOVER-1, UNCOVER-2 and UNCOVER-3 patients had baseline palmoplantar involvement (PPASI ≥0, n = 1092) and 9.1% (n = 350) had moderate-to-severe involvement, with mean baseline PPASI ~20, PASI ~24, and most (>60%) had static Physician's Global Assessment ≥4. Higher percentages of patients treated with ixekizumab vs. placebo or etanercept achieved PPASI 50 (approximately 80% vs. 32.9%, 67.8%; ixekizumab, placebo, etanercept, respectively) and PPASI 75 (approximately 70% vs. 18.8%, 44.1%; ixekizumab, placebo, etanercept, respectively) at week 12 (all P < 0.05). PPASI 100 was achieved by higher percentages of ixekizumab-treated patients vs. placebo (approximately 50% vs. 8.2%, P < 0.001) and ixekizumab Q2W-treated patients vs. etanercept (51.8% vs. 32.2%, P < 0.05). Outcomes were maintained or improved in patients continuing on ixekizumab Q4W through week 60. Differences between ixekizumab and placebo or etanercept were statistically significant as early as week 1.

Conclusion: In a subpopulation analysis of patients from phase 3 trials with moderate-to-severe non-pustular palmoplantar involvement and moderate-to-severe plaque psoriasis, ixekizumab treatment resulted in greater and more rapid improvements than placebo and etanercept at week 12; improvements were sustained with continued treatment.