After strutting its stuff against blockbusters in three head-to-head psoriasis trials, UCB’s Bimzelx has conquered another powerhouse product—AbbVie’s Skyrizi—in psoriatic arthritis (PsA).
A phase 3b study of 553 adults with active psoriatic arthritis has achieved its primary objective, showing the “statistically significant superiority” of Bimzelx over Skyrizi in reducing disease activity as measured by the ACR50 endpoint at Week 16, the Belgian company said.
ACR50 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.
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 includes adults with active PsA who were either new to biologic treatments or who had an inadequate response to one TNF inhibitor. UCB said it will provide results at a medical conference in the first half of this year.
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.
Analysts from Jefferies said that the win over Skyrizi “should help Bimzelx gain share in the rheumatology setting.” But they also pointed out that UCB’s release “omitted any mention of secondary endpoints, which were supposed to capture point joint and skin clearance.”
“Given IL-23 typically performs well in skin clearance, we would be interested to see the head-to-head performance here,” Jeffries wrote in a Wednesday note. “Until clarification, the unresolved question may temper enthusiasm.”
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), though Jefferies’ note indicates that UCB “tends to guide conservatively.”
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).