Ixekizumab is effective in the long-term management in moderate-to-severe plaque psoriasis: results from an Italian retrospective cohort study (the LOTIXE study)

Purpose Ixekizumab is a high-affinity monoclonal antibody that selectively targets interleukin (IL)-17A approved for the treatment of moderate-to-severe plaque psoriasis. The objective of this study was to describe the real-world long-term effectiveness of ixekizumab in patients with plaque psoriasis in Italy. Materials and Methods A retrospective study was conducted in patients affected by moderate-to-severe plaque psoriasis who were continuously treated with ixekizumab for at least 12 months. Patient data was obtained at 4-weeks, 12-weeks and 6-, 12-, 18- and 24-months after baseline (June 2017 and September 2019) from 10 sites. Results were analyzed by complete case approach, with sensitivity analysis performed to evaluate the impact of missing data. Results A total of 198 patients were enrolled in the study. At Month 24, 94.3% of patients achieved PASI75 response, while 85.1 and 71.8% achieved PASI90 and PASI100, respectively; and 91.1% of the patients achieved absolute PASI score & LE;2. Patients experienced psoriasis improvement at 4 weeks after starting treatment, and improvement was maintained with continued ixekizumab use. The quality of life of patients also improved significantly starting at Week 12, with sustained effect in the long term. Conclusion This 24-month observational cohort study confirmed that ixekizumab is effective in the long-term management of patients with moderate-to-severe plaque psoriasis.