Maintenance of skin clearance with ixekizumab treatment of psoriasis: Three-year results from the UNCOVER-3 study

Background: Psoriasis is a chronic disease that may require long-term treatment. Ixekizumab (IXE), which is a high-affinity monoclonal antibody that selectively targets interleukin 17A, is an approved therapy for patients with moderate-to-severe plaque psoriasis. Objective: To evaluate the efficacy and safety of IXE through 156 weeks from the UNCOVER-3 study in patients who were treated with the recommended dose regimen (160 mg of IXE at week 0, 80 mg every 2 weeks up to week 12, and 80 mg every 4 weeks thereafter). Methods: Patients randomized to IXE every 2 weeks, IXE every 4 weeks, etanercept twice weekly, or placebo were switched to IXE every 4 weeks during the long-term extension period. Efficacy data were summarized by using the as-observed, multiple imputation, and modified nonresponder imputation methods. Results: At week 156, 80.5% of patients had achieved at least a 75% improvement from baseline in their Psoriasis Area Severity Index (PASI) score, 66.0% had achived at least a 90% improvement from baseline in their PASI score, and 45.1% had achieved a 100% improvement from baseline in their PASI score with use of the modified nonresponder imputation method, and 97.2% and 86.2% of patients had achived at least a 75% improvement from baseline in their PASI score with use of the as-observed and multiple imputation methods, respectively. Similar response rates were observed in patients with baseline scalp, nail, or palmoplantar involvement. No new safety signals were identified through year 3. Limitations: No placebo or active comparison after week 12. Conclusion: IXE sustained high responses with clearance of skin and nail lesions, with no new safety concerns through 3 years.