UCB’s BE BOLD trial released Phase 3 week-16 data on Tuesday: 49.1% of patients on Bimzelx achieved ACR50 versus 38.4% on Skyrizi, a statistically significant gap. ACR50 is the American College of Rheumatology’s established response criterion for psoriatic arthritis trials, measuring at least a 50% improvement across joint symptoms, functional performance, and quality-of-life measures. Winning the primary endpoint head-to-head is the result UCB needed.
Bimzelx also edged ahead on minimal disease activity at 16 weeks: 43% versus 39.9% for Skyrizi. That difference didn’t reach statistical significance, which under the trial’s hierarchical testing structure closed off formal analysis of remaining secondary endpoints. UCB still reported numerically better joint relief at four weeks and complete skin clearance at 16 weeks.
Skyrizi generated $17.56 billion in 2025, a 49.7% year-on-year surge that made it one of pharma’s top sellers. AbbVie built the franchise to replace Humira, which fell from a $21.2 billion peak in 2022 to $4.54 billion last year under biosimilar pressure. Both drugs hold psoriatic arthritis and plaque psoriasis approvals.
This trial doesn’t change labels. What it does change is the burden of proof at formulary reviews. Payers read ACR50 head-to-head splits, and a 10-point primary endpoint gap is the document a pharmacy director cites when moving a competing product down a coverage tier.
UCB has also been spending: $2 billion upfront for Candid Therapeutics this month and $650 million upfront for Neurona Therapeutics last month. Tuesday’s trial data anchors the immunology rationale for that acquisition pace. EULAR 2026 is when the full BE BOLD presentation lands.
Rebecca Lauren