Long‐term efficacy and safety of risankizumab for the treatment of moderate‐to‐severe plaque psoriasis: interim analysis of the LIMMitless open‐label extension trial beyond 3 years of follow‐up

BACKGROUND: Psoriasis is a chronic inflammatory skin disease requiring prolonged treatment. New biologic therapies require long‐term evaluation to assess the durability of their efficacy and safety profiles over time. OBJECTIVES: To evaluate the long‐term efficacy and safety of risankizumab (RZB) for the treatment of psoriasis. METHODS: LIMMitless is an ongoing, phase III, open‐label extension study evaluating the long‐term efficacy and safety of RZB in adults with moderate‐to‐severe plaque psoriasis following multiple phase II/III studies. This analysis assessed efficacy through 172 weeks of continuous RZB treatment by examining the proportion of patients achieving ≥ 90% or 100% improvement in Psoriasis Area and Severity Index (PASI 90 and PASI 100), static Physician’s Global Assessment of clear or almost clear (sPGA 0/1) and Dermatology Life Quality Index of no effect on quality of life (DLQI 0/1). Safety was assessed by recording adverse events (AEs) through the data cutoff date. The study is registered at ClinicalTrials.gov (identifier: NCT03047395). RESULTS: Of 955 patients randomized to RZB 150 mg in the base studies, 897 patients continued into LIMMitless; 799 patients were still receiving treatment in LIMMitless at the time of data cutoff for this analysis. After 172 weeks of continuous RZB treatment, 85·5% of patients achieved PASI 90, 54·4% achieved PASI 100, 85·2% achieved sPGA 0/1, and 78·4% achieved DLQI 0/1 using modified nonresponder imputation. Rates of AEs leading to discontinuation and AEs of safety interest were low with long‐term treatment and comparable with those identified in the base studies. CONCLUSIONS: Overall, long‐term continuous RZB was well tolerated and showed high and durable efficacy over 172 weeks.