Abstract
Objective The safety and efficacy of bimekizumab, a dual interleukin (IL)-17A and IL-17F inhibitor, have been demonstrated over 2 years across the full disease spectrum of axial spondyloarthritis (axSpA). We report long-term safety and efficacy of bimekizumab over 3 years.
Methods Patients who completed week 52 of the phase III BE MOBILE 1 (nonradiographic axial spondyloarthritis [axSpA]; ClinicalTrials.gov: NCT03928704) and BE MOBILE 2 (radiographic axSpA; NCT03928743) studies were eligible to enter an ongoing open-label extension (OLE; NCT04436640) and continue receiving subcutaneous bimekizumab 160 mg every 4 weeks. Safety outcomes for patients who received ≥ 1 dose of bimekizumab and efficacy outcomes for all randomized patients are reported over 3 years (164 weeks [112-week OLE]).
Results During the overall safety period, 90.4% (519/574) of patients had ≥ 1 treatment-emergent adverse event. Fungal infection exposure-adjusted incidence rate (EAIR) per 100 patient-years (PY) was 9.4 (the majority were Candida infections, 5.3/100 PY; most infections were mild or moderate, none were serious or systemic). The EAIRs per 100 PY for inflammatory bowel disease and uveitis were 0.5 and 1.5, respectively. No major adverse cardiovascular events or deaths occurred. EAIRs, including those for Candida infections, were generally lowest in the third year. The efficacy of bimekizumab observed through 2 years was sustained through week 164. At week 164, 57.0% of patients achieved an Axial Spondyloarthritis Disease Activity Score (ASDAS) indicating low disease activity (< 2.1), including 28.7% who achieved ASDAS inactive disease (< 1.3). Bimekizumab treatment also led to sustained improvements in Bath Ankylosing Spondylitis Functional Index (BASFI) and health-related quality of life scores and sustained control of magnetic resonance imaging (MRI) inflammation through week 164, with 59.4% and 77.8% of patients achieving Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint scores < 2 and Berlin spine scores ≤ 2, respectively.
Conclusion Bimekizumab was well tolerated over 3 years, with no new safety signals observed. Across the full disease spectrum of axSpA, patients demonstrated sustained clinical efficacy and inflammation control over 3 years.
