Two months after UCB revealed the success of Bimzelx in a head-to-head trial against AbbVie’s Skyrizi in patients with psoriatic arthritis (PsA), the Belgian drugmaker has unveiled the detailed results.
In the phase 3b study that included 553 patients, 49% of those on Bimzelx achieved reduced disease activity versus 38% of those on Skyrizi at week 16. The result was deemed to be statistically significant, UCB said.
The disease activity primary endpoint was measured by ACR50, which is a composite efficacy measurement, specified by the American College of Rheumatology, which indicates 50% or greater improvement from baseline in tender or swollen joint counts in addition to 50% improvement in three of five other disease markers.
Bimzelx outperformed Skyrizi in secondary measures, but none achieved statistical significance, UCB said. In one of those endpoints, Bimzelx produced complete skin clearance at week 16 for 53% of patients compared to 47% for those on Skyrizi. In another secondary measure, Minimal Disease Activity (MDA), which assesses overall disease control, Bimzelx topped Skyrizi 43% to 40%.
In a secondary endpoint, which identified how many patients achieved ACR50 after four weeks, Bimzlex produced a 20% success rate compared to 7% for Skyrizi.
It is the first time an approved treatment has demonstrated superiority in PsA over an IL-23 inhibitor such as Skyrizi, UCB said. Bimzelx is the first therapy to selectively inhibit the IL-17F and IL-17A proinflammatory proteins. The study included adults with active PsA who were either new to biologic treatments or who had an inadequate response to one TNF inhibitor.
It’s another win for Bimzelx, which has already topped Novartis’ IL-17 Cosentyx, Johnson & Johnson’s IL-12 and IL-23 Stelara and AbbVie’s TNF blocker Humira in previous psoriasis studies.
“Delivering high-level clinical responses is crucial for people with psoriatic arthritis. Achieving ACR50 level responses in clinical trials indicates joint improvements that correlate closely with clinically meaningful reductions in disease activity, inflammation control and consequent improvements in quality of life,” Iain McInnes, of the University of Glasgow, College of Medical Veterinary and Life Sciences, said in a release.
The results will be presented during the European Alliance of Associations for Rheumatology (EULAR) meeting in London from June 3 to June 6.
Bimzelx sales increased significantly from 607 million euros ($716 million) in its first full year on the market to 2.2 billion euros ($2.6 billion) in 2025. The annual haul was already halfway to the company’s peak sales projection of 4 billion euros ($4.4 billion). Bimzelx helped drive UCB to a 26% increase in revenue in 2025 to 7.7 billion euros ($8.7 billion).
Bimzelx’s rapid uptake is mirroring that of Skyrizi, which achieved sales of $355 million in its first full year on the market, followed by $1.6 billion in 2020 and $2.9 billion the following year. Last year, Skyrizi raked in $17.6 billion in revenue.
In addition to its indications for psoriasis and PsA, Skyrizi is approved for Crohn’s disease and ulcerative colitis. Beyond psoriasis and PsA, Bimzelx is also approved for active non-radiographic axial spondyloarthritis, active ankylosing spondylitis and most hidradenitis suppurativa (HS).