Long-term effectiveness of bimekizumab in plaque psoriasis: 2-year drug survival from a real-life multicentre Italian study

BACKGROUND: Bimekizumab, a monoclonal antibody targeting both interleukin-17A and interleukin-17F, has shown strong efficacy in moderate-to-severe plaque psoriasis. However, long-term real-world data on its effectiveness and treatment persistence remain limited. OBJECTIVES: To evaluate the 2-year drug survival of bimekizumab in a real-life setting across multiple Italian dermatology centres. METHODS: This multicentre, retrospective, observational study included adult patients with moderate-to-severe plaque psoriasis who initiated bimekizumab between May 2022 and November 2024. Drug survival was assessed using Kaplan-Meier analysis. Univariable and multivariable Cox regression models were used to identify predictors of treatment persistence. RESULTS: In total, 826 patients were included (66.6% male; mean age 52.3 years, SD 14.9). At baseline, the mean Psoriasis Area and Severity Index (PASI) score was 15.5 (SD 8.9), which decreased to 1.4 (3.3) at the last follow-up. Estimated drug survival rates at 12, 18 and 24 months were 89.1%, 85.0% and 82.4%, respectively. In total, 129 patients discontinued treatment, primarily due to adverse events (n = 68) and ineffectiveness (n = 31). In both univariable and multivariable analyses, male sex was significantly associated with a lower risk of discontinuation (hazard ratio 0.65, P = 0.002 and hazard ratio 0.67, P = 0.008, respectively). Other factors, including body mass index (BMI) > 30 kg m-2, presence of psoriatic arthritis, baseline PASI > 15 and prior biologic exposure, were not significantly associated with treatment discontinuation. CONCLUSIONS: This real-world study demonstrates the long-term effectiveness and high drug survival of bimekizumab up to 24 months, across diverse patient profiles, regardless of BMI, disease severity, prior biologic exposure or presence of psoriatic arthritis.