UCB Presents New Long-Term Data on Bimzelx in Psoriatic Arthritis and Axial Spondyloarthritis
UCB laboratories disclosed on Wednesday Phase 2/3 data and their open-label extensions regarding Bimzelx (bimekizumab) in the treatment of psoriatic arthritis and axial spondyloarthritis. These results, presented at EULAR 2026, reported clinical effects observed up to three years in psoriatic arthritis and provided imaging data for non-radiographic axial spondyloarthritis.
Early Control and Sustained Symptom Improvement
Data from the BE OPTIMAL and BE COMPLETE trials indicate that patients with psoriatic arthritis who quickly met response criteria (resolution of swollen joint count or ACR50 criteria) within the first sixteen weeks recorded more significant improvements in pain and fatigue after three years of observation. In the biologic-naive treatment cohort (bDMARD), 48.3% of patients achieved resolution of swollen joint count by week 16, while 44.8% met the ACR50 criterion. Among responders who reached this initial target, 64.9% of treatment-naive patients and 80.1% of patients previously treated with tumor necrosis factor inhibitors reported at least a 50% improvement in pain at three years. Similar trends were observed for fatigue, measured by the FACIT-Fatigue scale.
Minimal Radiographic Progression in Psoriatic Arthritis
Radiographic analysis of hands and feet in biologic-naive patients in the BE OPTIMAL trial demonstrated minimal structural progression. Out of 579 patients with baseline and three-year radiographs, 73.7% achieved a radiographic progression score of less than 0.5 (van der Heijde modified Total Sharp Score), and 58.2% showed complete absence of progression (score ≤ 0.0). Younger patients (under 45 years), those with a shorter disease duration, and those with a lower initial swollen joint count recorded the lowest rates of radiographic progression, according to the statement.
No Ankylosis in Non-Radiographic Axial Spondyloarthritis
In non-radiographic axial spondyloarthritis, magnetic resonance imaging (MRI) data over two years of observation revealed a substantial reduction in inflammation of the sacroiliac joints. The SPARCC inflammation score recorded an average reduction of 6.2 points. Among patients with initial inflammation, 50.9% achieved MRI remission at two years. The structural analysis highlighted an average reduction of 1.5 points in erosions and increases of 0.7 points in bone filling and 0.9 points in fatty lesions. No cases of ankylosis of the sacroiliac joints were observed on MRI, indicating the absence of structural damage progression. According to UCB, the data presented constitutes the first set of two-year structural MRI data in non-radiographic axial spondyloarthritis evaluating a biological immune response modulator.
