COPENHAGEN – Use of the dual interleukin (IL)–17 inhibitor bimekizumab (Bimzelx) was associated with rapid reductions in signs and symptoms of radiographic axial spondyloarthritis, reported investigators in the BE MOBILE 2 phase 3 trial.
At least half of all patients achieved an Ankylosing Spondylitis Disease Activity Score (ASDAS) of less than 2.1 by week 24 of treatment with bimekizumab, and there were marked reductions in objective signs of inflammation, reported Désiréé van der Heijde, MD, PhD, of Leiden (Netherlands) University Medical Center.
“The safety we have seen in this trial was consistent with what we have seen [with bimekizumab] in other trials and other diseases,” she said at the annual European Congress of Rheumatology.
IL-17 inhibitor times 2
Bimekizumab is a monoclonal immunoglobulin 1 antibody that selectively inhibits IL-17A and IL-17F. It is approved in the European Union for treating adults with moderate to severe plaque psoriasis.
In the BE MOBILE 2 trial, investigators enrolled patients aged 18 years and older who had ankylosing spondylitis, who met modified New York criteria, who had active disease at screening and at baseline, as defined by having a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score of 4 or more and spinal pain of 4 or more on a scale of 0-10, and whose disease failed to respond to two different NSAIDs or who were either intolerant of or had contraindications to NSAIDs.
The patients were randomly assigned on a 2:1 basis to receive either bimekizumab 160 mg every 4 weeks (221 patients) or placebo (111 patients) for 16 weeks. All patients were switched over at 16 weeks to bimekizumab maintenance for up to 1 year of total treatment.
Dr. Van der Heijde reported 24-week data from the trial, including data from 8 weeks of additional follow-up.
All endpoints met
The trial met its primary endpoint of 40% improvement in Assessment of Spondyloarthritis International Society response criteria (ASAS 40) at week 16. There was a 44.8% improvement with bimekizumab, compared with 22.6% with placebo (P < .001).
All secondary endpoints also favored the bimekizumab arm, including ASAS 40 among patients who had not previously received a tumor necrosis factor (TNF)–alpha inhibitor, ASAS 20, BASDAI functional index, ankylosing spondylitis quality-of-life index, and others.
Responses to bimekizumab were consistent across subpopulations of patients with or without prior TNF-alpha inhibitor exposure, Dr. van der Heidje said.
In addition, use of bimekizumab was associated with a significant improvement from baseline, compared with placebo, in objective measures of inflammation, including MRI spine Berlin score at week 16 (mean, –2.3 vs. 0; P < .001), Spondylitis Research Consortium of Canada (SPARCC) MRI sacroiliac joint score at week 16 (mean, –5.6 vs. 1.1), and high-sensitivity C-reactive protein at week 16 (mean, 2.4 vs. 6.3 mg/L; P < .001).
The most frequent treatment-related adverse events were nasopharyngitis, diarrhea, and oral candidiasis, all of which were more common in the bimekizumab arm, as well as headache, the incidence of which was similar between the arms.
Overall, 6.4% of patients taking bimekizumab had fungal infections, compared with none in the placebo group. The infections were mild or moderate, localized, and mucocutaneous in nature. Only two patients discontinued the drug because of fungal infections: one for oral candidiasis, and one for esophageal candidiasis.