Effectiveness of bimekizumab in psoriatic arthritis. A multicenter real‐life study with clinical and ultrasound evaluation in the Lazio region, Italy

Background: Bimekizumab, a monoclonal antibody targeting interleukin (IL)-17A and IL-17F, has shown efficacy in psoriatic arthritis (PsA) clinical trials, but real-world data on its effectiveness are limited. This study aimed to evaluate its real-world effectiveness in PsA patients treated in dermatologic settings. Methods: We conducted a multicenter, prospective, observational study in dermatology units across Lazio, Italy, including 20 patients with psoriasis and PsA treated with bimekizumab. Rheumatologic assessments were performed at baseline and after 16 weeks, evaluating tender and swollen joint counts, the Visual Analog Scale (VAS) pain score, the Disease Activity in Psoriatic Arthritis (DAPSA) score, and the Leeds Enthesitis Index (LEI). Ultrasound evaluations (US) of joints and entheses were conducted at baseline and Week 16. Results: Twenty patients were enrolled, including 10 bio-experienced patients. At 16 weeks, significant improvements were observed in tender joint count (3.65 to 2.15, p = 0.004), swollen joint count (1.35 to 0.55, p = 0.028), VAS pain score (6.35 to 3.35, p < 0.001), DAPSA (22.71 to 8.67, p < 0.001), and LEI (0.85 to 0.25, p = 0.004). US revealed a decrease in the number of patients with power Doppler (PD) positive joints (45% to 25%) and a reduction in synovial PD score (2.26 to 0.81, p = 0.002). The number of patients with US-positive enthesitis decreased (50% to 30%), with a significant reduction in the enthesis PD score (1.00 to 0.25, p = 0.047). Four patients (20%) developed mild candidiasis, with no treatment discontinuation. Conclusions: Bimekizumab demonstrated significant, rapid improvements in real-world PsA patients, including those with prior biologic failures. Its favorable safety profile and effectiveness highlight its potential as a valuable treatment option for PsA.