UCB SA announced positive top-line interim analysis results showing that the Phase 3 BE MOBILE 1 study met the primary and all ranked secondary endpoints. BE MOBILE 1 is the first study to evaluate the efficacy and safety of bimekizumab in adults with active non-radiographic axial spondyloarthritis . In the BE MOBILE 1 study, bimekizumab demonstrated a statistically significant and clinically meaningful improvement over placebo in the proportion of patients who achieved the Assessment of SpondyloArthritis International Society 40 % response at week 16, the primary endpoint of the study.

ASAS40 measures improvements in disease across four different domains – patient global assessment of disease activity, spinal pain, physical function and inflammation.2 The primary endpoint used in this study, ASAS40, set a high threshold for improvement in patient-reported outcomes, i.e., at least a 40% improvement relative to baseline. In BE MOBILE 1, the safety profile of bimekizumab was consistent with safety data seen in previous studies with no new observed safety signals. The safety and efficacy of bimekizumab in nr-axSpA have not been established.

Bimekizumab is not approved for use in nr-axSpA or ankylosing spondylitis by any regulatory authority worldwide. Results from the BE MOBILE 1 study will be presented at upcoming medical conferences and published in a peer-reviewed medical journal. BE MOBILE 1 is a randomized, multicenter, double-blind, placebo-controlled, parallel group, Phase 3 study designed to evaluate the efficacy and safety of bimekizumab in the treatment of adult patients with active non-radiographic axial spondyloarthritis .

BE MOBILE is the first Phase 3 bimekizumab research program to include patients from China in its study population. The 52-week study is ongoing with top-line interim analysis results presented. BE MOBILE 1 enrolled participants with active disease.

Study participants had to have adult-onset axial spondyloarthritis meeting Assessment of SpondyloArthritis International Society classification criteria, inflammatory back pain for at least three months and no definitive radiographic sacroiliitis confirmed by central reading. Patients needed to demonstrate objective signs of inflammation by elevated C-reactive protein and/or positive magnetic resonance imaging. Study participants also had to have either failed to respond to two different nonsteroidal anti-inflammatory drugs given at the maximum tolerated dose for a total of four weeks or have had a history of intolerance to or a contraindication to NSAID therapy.

Patients who had taken a tumor necrosis factor alpha inhibitor had to have experienced an inadequate response or intolerance to treatment. Non-radiographic axSpA falls under the umbrella of axial spondyloarthritis, which also includes ankylosing spondylitis . AxSpA is a painful chronic inflammatory disease that primarily affects the spine and the joints linking the pelvis and lower spine nr-axSpA is defined clinically by the absence of definitive x-ray evidence of structural damage to the sacroiliac joints.

The leading symptom of axSpA is inflammatory back pain that improves with exercise, but not with rest. Fatigue and stiffness are additional key symptoms. Other common clinical features frequently include acute anterior uveitis, enthesitis, peripheral arthritis, psoriasis, inflammatory bowel disease and dactylitis . The overall prevalence of axSpA is 0.2 % to 1.4% of adults.

Approximately half of all patients with axSpA are patients with nr-axSpA. Approximately two-thirds of patients with AS are men, while nr-axSpA is more common among women with the disease. AxSpA onset usually occurs before the age of 45, often in the 20s.

10 to 40 % of patients with nr-axSpA progress to AS over 2 to 10 years.