FDA approves bimekizumab, now Bimzelx, for active AS and nr-axSpA
Treatment is antibody-based therapy to block IL-17A, IL-17F proteins
The U.S. Food and Drug Administration (FDA) has approved Bimzelx (bimekizumab-bkzx) for adults with active ankylosing spondylitis (AS), UCB Biopharm, the therapy’s developer, has announced. The dual interleukin-17A (IL-17A)/IL-17F inhibitor’s approval also extends to adults with active nonradiographic axial spondyloarthritis (nr-axSpA) with signs of inflammation and active psoriatic arthritis.
“The approval of Bimzelx in the U.S. across three new indications — active psoriatic arthritis, active nonradiographic axSpA with objective signs of inflammation, and active ankylosing spondylitis — highlights the clinical benefit of dual inhibition of both IL-17A and IL-17F for patients, and provides an opportunity for more people living with chronic inflammatory diseases to achieve meaningful outcomes,” Emmanuel Caeymaex, executive vice president, head of patient impact and chief commercial officer at UCB, said in a company press release.
In axial spondyloarthritis (axSpA), an abnormal inflammatory response damages the joints of the spine, chest, and pelvis. In nr-axSpA, joint damage isn’t detectable on X-rays, whereas in radiographic axSpA (r-axSpA), or ankylosing spondylitis (AS), joint damage can be seen. Psoriatic arthritis affects the joints of the hands and feet and is also associated with psoriasis, a condition marked by dry, scaly, or itchy patches of skin.
Symptoms of AS and nr-axSpA include swelling, pain, tenderness, and stiffness in the joints. A hallmark symptom of AS is pain and stiffness in the lower back, hips, and buttocks.
“People living with nonradiographic axial spondyloarthritis and ankylosing spondylitis experience pain, stiffness and fatigue that can limit their daily activities, ability to work, and quality of life,” said Seth Ginsberg, co-founder and president of Global Health Living Foundation and CreakyJoints, U.S. “A new treatment option offers the opportunity for more patients to reach their treatment goals.”
Bimekizumab is an antibody-based therapy that’s designed to block the action of IL-17A and IL-17F, two immune signaling proteins that drive inflammatory processes implicated in various autoimmune conditions. By selectively blocking the proteins, bimekizumab should reduce inflammation and ease symptoms associated with each condition.
Results of BE MOBILE studies
Data from two Phase 3 clinical trials, BE MOBILE 1 (NCT03928704) and BE MOBILE 2 (NCT03928743), supported Bimzelx’s approvals for active nr-axSpA and AS. The trials also supported its approval in Europe in June.
Given by injection under the skin, or subcutaneously, patients in both trials received either 160 mg of Bimzelx or a placebo every four weeks for 16 weeks, or about four months. All were then treated with bimekizumab for up to a year.
The primary outcome measure in both trials was an ASAS40 response after one year, meaning an improvement of at least 40% on the Assessment in SpondyloArthritis International Society. ASAS40 reduction must be seen in three or more of four domains, particularly pain, inflammation, function, and a patient’s global assessment of disease.
Across both studies, 45% of participants with AS and 48% with nr-axSpA achieved an ASAS40 response by week 16. By a year, the percentage who achieved an ASAS40 response increased to 58% with AS and 61% with nr-axSpA.
Other assessments of inflammation, including blood levels of C-reactive protein and MRI scans of the hips and spine, showed improvements. One year of treatment also eased spinal pain and morning stiffness and enhanced patients’ physical function and quality of life.
Among those who switched from the placebo to Bimzelx at 16 weeks, treatment-related improvements were comparable to those who’d taken it since the trials’ beginning.
“In the Phase 3 clinical studies, patients treated with [Bimzelx] saw improvements in signs and symptoms and key measures of disease activity at Week 16 which were sustained to one year and consistent across patients with nonradiographic axial spondyloarthritis and ankylosing spondylitis,” said Atul Deodhar, MD, professor of medicine and medical director of rheumatology clinics at the Oregon Health & Science University.
The most common side effects included the common cold (9.1% with AS, 12.3% with nr-axSpA), upper respiratory tract infection (6.4% with AS, 9.4% with nr-axSpA), and oral candidiasis, a fungal infection (6.1% in AS, 7.4% with nr-axSpA).
Data from the completed Phase 2b BE AGILE trial (NCT02963506) and its open-label extension study (NCT03355573) demonstrated Bimzelx’s long-term efficacy in AS. Results showed that up to five years of treatment safely led to sustained reductions in disease activity and symptoms and improvements in physical function and life quality. The therapy’s long-term safety and efficacy are also being evaluated in an ongoing extension study called BE MOVING (NCT04436640).
“The U.S. rheumatology community welcomes the approval of [Bimzelx] for use across the entire spectrum of axial spondyloarthritis, especially given that there are few options approved currently to treat both nonradiographic axial spondyloarthritis and ankylosing spondylitis,” Deodhar said.