Bimekizumab Shows Sustained Efficacy in Treating Axial Spondyloarthritis for 52 Weeks

Bimekizumab demonstrated sustained efficacy in treating axial spondyloarthritis (axSpA) up to week 52, with a safety profile consistent with previous observations, according to phase 3 data published in Annals of the Rheumatic Diseases.¹

"Dual inhibition of IL-17A and IL-17F with subcutaneous [bimekizumab] 160 mg [every 4 weeks] led to clinically meaningful improvements in a range of efficacy outcomes, across the full disease spectrum of axSpA to week 52," investigators wrote.

The 52-week randomized controlled trials BE MOBILE 1 and BE MOBILE 2 aimed to assess the long-term efficacy of bimekizumab (Assessment of Spondyloarthritis International Society ≥ 40% improvement; ASAS40) across various clinical response criteria, disease activity measures, patient-reported outcomes, and peripheral manifestations.

Patients switching from placebo to bimekizumab at week 16 exhibited comparable improvements by week 52 to those initially assigned the intervention group. Investigators noted the safety profile observed throughout the study remained consistent with previous data.

Axial spondyloarthritis encompasses both non-radiographic (nr-) and radiographic (r-) forms of the condition and is characterized by inflammation primarily in the spine and sacroiliac joints. Bimekizumab is a monoclonal IgG1 antibody that targets IL17F and IL17A and has exhibited long-term treatment reliability in psoriatic arthritis, another inflammatory rheumatic disease.²

The research, comprising BE MOBILE 1 (for nr-axSpA) and BE MOBILE 2 (for r-axSpA), included a 16-week, double-blind, placebo-controlled phase followed by a 36-week maintenance period. Subsequently, all patients received subcutaneous bimekizumab 160 mg every 4 weeks.¹

Rapid responses to the therapy were evident for the primary endpoint, ASAS40 at week 16, with a notable separation from placebo observed after the initial dose, the study stated. Both trials met the primary endpoint with statistical significance (P < .001). The proportion of patients initially randomized to the intervention group achieving response was consistently maintained from week 16 to week 52, indicating sustained efficacy over time in both nr-axSpA and radiographic r-axSpA axSpA.

Analysis of ASAS40 responses at week 16 revealed sustained efficacy of bimekizumab up to week 52, irrespective of patients' prior exposure to tumor necrosis factor inhibitors (TNFi). Patients who were TNFi-naïve and TNFi-inadequate responder (TNFi-IR) exhibited sustained ASAS40 responses from week 16 to week 52, with only slight variations observed in certain subgroups.

The study assessed additional secondary endpoints, including ASAS20 and ASAS partial remission (ASAS PR), which also showed significant improvements with bimekizumab compared with placebo at week 16. These improvements were sustained through week 52 among patients initially randomized to the intervention, while patients switching from placebo to intervention exhibited progressive improvements over time, eventually reaching similar levels to those of bimekizumab-randomized patients by the end of the study.

The BE MOBILE trials' findings suggest that bimekizumab is an effective treatment option, offering sustained efficacy across the entire disease spectrum of axSpA, investigators noted. The ongoing open-label extension trial, BE MOVING, will continue to evaluate the long-term efficacy and safety of bimekizumab up to 3 years of treatment, potentially providing further insights into its role in axSpA management and influencing future treatment guidelines and policies.

References

1. Baraliakos X, Deodhar A, van der Heijde D, et al. Bimekizumab treatment in patients with active axial spondyloarthritis: 52-week efficacy and safety from the randomised parallel phase 3 BE MOBILE 1 and BE MOBILE 2 studies. Ann Rheum Dis. 2024;83(2):199-213. doi:10.1136/ard-2023-224803

2. Joszt L. Indirect comparison finds bimekizumab more effective than guselkumab in psoriatic arthritis. AJMC^®. Published April 4, 2024. https://www.ajmc.com/view/indirect-comparison-finds-bimekizumab-more-effective-than-guselkumab-in-psoriatic-arthritis