Ankylosing spondylitis treatment benefits sustained over 2 years
Bimzelx is an antibody made to attach to proteins that signal for inflammation
Most adults with active ankylosing spondylitis or non-radiographic axial spondyloarthritis who achieved low or no disease activity after four months on the recently approved Bimzelx (bimekizumab-bkzx) maintained their clinical response over at least two years.
Two-year data from the Phase 3 clinical trials BE MOBILE 1 (NCT03928704) and BE MOBILE 2 (NCT03928743) along with their open-label extension BE MOVING (NCT04436640) showed UCB’s Bimzelx continued to be safe over the long term.
“These new two-year data, revealing high levels of response, offer exciting insights into [Bimzelx]’s sustained efficacy,” Fiona du Monceau, head of patient evidence at UCB, said in a company press release, calling attention to its potential “as an effective approach to targeting key inflammatory pathways.”
While some treatments help ease symptoms of axial spondyloarthritis, “a major challenge for practicing rheumatologists is that existing treatments may lose efficacy over time, leaving patients vulnerable to debilitating symptoms,” said Fabian Proft, MD, from Charité Universitätsmedizin Berlin, in Germany.
Bimzelx is an antibody that’s designed to attach to interleukins IL-17A and IL-17F, proteins that signal for inflammation in the body. By attaching to them, Bimzelx prevents them from interacting with their receptors, which reduces inflammation and eases symptoms of inflammatory diseases.
Bimzelx is approved in the U.S. to treat adults with active axial spondyloarthritis, an inflammation of the spine that causes pain and stiffness in the lower back among other symptoms. A similar approval was also granted in the European Union.
The approvals include those who have signs of disease on X-rays, or ankylosing spondylitis, as well as those with clear signs of inflammation, but no signs of disease on X-rays, that is, non-radiographic axial spondyloarthritis. Bimzelx is also approved for plaque psoriasis and active psoriatic arthritis, two other inflammatory diseases.
Given as an injection under the skin, or subcutaneously, Bimzelx helped more than half the participants with either ankylosing spondylitis or non-radiographic axial spondyloarthritis achieve ASAS40 response after 16 weeks, or about four months. Patients achieving an ASAS40 response improve by 40% or more in at least three out of four domains, including pain.
Less inflammation with Bimzelx
According to new one-year data shared in an oral presentation at the American College of Rheumatology (ACR) Convergence 2024 in Washington D.C., Bimzelx resulted in less inflammation and fewer structural changes on MRI scans of the sacroiliac joints, which join the spine to the pelvis.
More than two-thirds of patients achieved remission on MRI scans, or had no signs of inflammation, after a year of treatment, whether they had ankylosing spondylitis (75%) or non-radiographic axial spondyloarthritis (79.5%). These proportions are higher than those observed at 16 weeks — 58.3% and 66.7%, respectively — or after switching from a placebo to Bimzelx (66.7% and 56.3%).
“Across the full disease spectrum of [axial spondyloarthritis], [Bimzelx] had substantial impact on [sacroiliac joint] MRI inflammation and structural lesions, indicating potential tissue repair after only 16 [weeks],” the researchers wrote in an abstract to the oral presentation. “This continued to improve from 16 to 52 [weeks].”
Over time, inflammation in ankylosing spondylitis causes accumulating damage that can be seen on X-rays. Two-year data presented at ACR Convergence 2024 showed minimal progression of structural damage, however, with 85.3% of patients who entered BE MOVING not progressing at all, based on X-rays.
Proft, the first author of another abstract presented at the conference, said Bimzelx “met stringent clinical endpoints, with high levels of efficacy across multiple domains of axial spondyloarthritis … sustained for two years, demonstrating [Bimzelx’s] ability to remain effective over the long term.”
Of the patients who achieved an ASAS40 response after 16 weeks in BE MOBILE 1 and BE MOBILE 2, 85.7% maintained their clinical response over 104 weeks, or two years. Similar observations were made for those who achieved low disease activity (89.3%) or inactive disease (76%).
Consistent with one-year data, Bimzelx continued to be safe after an additional year of treatment, with the most common side effects being COVID-19, the common cold, and upper respiratory tract infection, according to an analysis that pooled data from 848 patients with axial spondyloarthritis with those of 1,409 patients with psoriatic arthritis.
