UCB: bimekizumab kept a numerical ACR50 lead over risankizumab at Week 24 in psoriatic arthritis, Phase 3b

On Nov. 9, 2026, UCB announced in Atlanta, according to prnewswire.com, Week 24 data for BIMZELX (bimekizumab-bkzx) from the Phase 3b BE BOLD study in adults with active psoriatic arthritis (PsA). prnewswire.comprnewswire.comprnewswire.comOpen source ↗ The previously reported Week 16 results showed statistically significant superiority in ACR50 joint outcomes versus risankizumab. Numerically greater ACR50 rates were sustained through Week 24, the company said. The full findings are being presented at the 2026 ACR Convergence in Orlando, Florida, held November 6–11.

BE BOLD design and treatment groups

BE BOLD is a multicenter, randomized, double-blind, risankizumab-controlled, parallel-group study of 553 adults with active PsA. Participants were either naive to biologic treatment or had previously received one tumor necrosis factor inhibitor with an inadequate response or intolerance. They were randomized 1:1 to BIMZELX or risankizumab. The primary endpoint is ACR50 at Week 16, and the study stays double-blind until Week 24.

The Week 24 results are reported for the BIMZELX total group (n=277). It includes 248 participants with no or mild psoriasis who received 160 mg every four weeks, and 29 with moderate or severe psoriasis who received 320 mg every four weeks to Week 16 and every eight weeks thereafter. The risankizumab group (n=276) received 150 mg at baseline, Week 4 and Week 16. At baseline, 10.5% of the BIMZELX group and 11.2% of the risankizumab group had moderate-to-severe psoriasis in addition to PsA. All visits after discontinuation due to adverse events or lack of efficacy were counted as non-response.

Safety and presentation at ACR

Overall treatment-emergent adverse events were comparable between the treatments. The exception was a higher rate of mild-to-moderate localized Candida infections in the BIMZELX arm. BE BOLD was not powered to compare safety. prnewswire.comprnewswire.comprnewswire.comOpen source ↗

Rheumatologist and dermatologist Joseph F. Merola, MD-MMSc, said bimekizumab produced rapid and greater ACR50 responses that were sustained to six months, along with high rates of complete skin clearance. The oral presentation is scheduled for 10:15 a.m. ET on Tuesday, November 10. UCB will present 18 abstracts at the meeting across its immunology portfolio in PsA, axial spondyloarthritis, rheumatoid arthritis and systemic lupus erythematosus.

BIMZELX is a humanized monoclonal IgG1 antibody designed to selectively inhibit interleukin 17A and interleukin 17F.