Bimekizumab Offers Improvements Across Full Spectrum of Axial Spondyloarthritis in Phase 3 Trials

New data announced today demonstrate consistent improvements among patients treated with bimekizumab when compared with placebo in patients with axial spondyloarthritis (axSpA), including non-radiographic axSpA (nr-axSpA) and ankylosing spondylitis (AS).

According to UCB, the phase 3 studies, BE MOBILE 1 and BE MOBILE 2 will be presented at the European Congress of Rheumatology (EULAR) 2022, along with the phase 2b BE AGILE study, in which bimekizumab showed maintenance of clinical responses over 3 years in patients with active ankylosing spondylitis.

The BE MOBILE Studies

In the treatment group of both studies patients were given 160 mg of bimekizumab every 4 weeks. The BE MOBILE 1 study included patients with active nr-axSpA and BE MOBILE 2 included patients with active ankylosing spondylitis.

Both studies met their primary endpoint of Assessment of SpondyloArthritis International Society 40 (ASAS40) at week 16 with statistical significance, as well as all ranked secondary endpoints, when compared to placebo.

The first trial demonstrated at week 16 that 47.7% of patients with nr-axSpA who received the treatment achieved ASAS40 compared with 21.4% of those in the placebo group. Similarly, in the second trial, investigators observed 44.8% of patients with ankylosing spondylitis who received treatment achieved ASAS40 compared with 22.5% of placebo.

According to UCB, response rates increased to week 24 and a rapid achievement of ASAS40 response was seen for patients switching from placebo to bimekizumab at week 16.

“Today’s findings from the BE MOBILE 1 and BE MOBILE 2 studies provide clear evidence supporting the potential of bimekizumab in both nr-axSpA and AS, and highlight the meaningful clinical outcomes that can be achieved by targeting IL-17F in addition to IL-17A," Atul Deodhar, MD, MRCP, Professor of Medicine, Division of Arthritis and Rheumatic Diseases, Oregon Health & Science University, said in a statement. "Patients with nr-axSpA and AS have a similar burden of disease and a treatment that could potentially show consistent outcomes across the full spectrum of disease is encouraging.”

Bimekizumab Efficacy Outcomes

At the start of the trials, most patients (> 97%) had high or very high disease activity. Investigators observered that the outcomes included changes in Ankylosing Spondylitis Disease Activity Score (ASDAS) reports, as well as changes in inflammation in the sacroiliac joints and spine, measured by Magnetic Resonance Imaging (MRI).

Approximately half of the patients treated with bimekizumab from the onset of the study achieved a low disease activity defined as ASDAS<2.1, by week 24. substantial reductions in inflammation in the sacroiliac joints and spine for both AS and nr-axSpA patients at week 16 were also observed among these patients.

“Patients with axSpA live with a range of debilitating symptoms including chronic back pain and difficulties performing everyday tasks," Désirée van der Heijde, Professor of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands, said in a statement.

"These interim results from the BE MOBILE 1 and BE MOBILE 2 studies are encouraging, showing that treatment with bimekizumab versus placebo improved signs and symptoms, reduced disease activity and inflammation, and improved physical function," she continued. "We look forward to the 52-week results from these studies expected later this year.”