5 minAt the recently held Digestive Disease Week (DDW) 2026 (May 2–5), Johnson & Johnson (J&J) unveiled the latest data for JNJ-4804, a fixed-dose co-antibody targeting IL-23 and TNF-α. In Phase 2b clinical trials for refractory inflammatory bowel disease (IBD), the drug demonstrated efficacy surpassing single-target therapies. J&J is now set to advance the program into Phase 3, potentially offering a breakthrough solution for highly refractory patients who have failed existing treatments.
Clinical Efficacy: Core Data from the DUET Studies
The newly released data from the DUET-CD (Crohn’s Disease) and DUET-UC (Ulcerative Colitis) studies focused on patients with moderately to severely active disease who were resistant to systemic treatments (refractory). The results at Week 48 regarding clinical remission and endoscopic response were highly compelling:
1. DUET-CD (Crohn’s Disease) Data:
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Overall Population: At Week 48, the JNJ-4804 group achieved a clinical remission rate of 50.8% and an endoscopic response rate of 38.1%. In comparison, the active control monotherapies showed lower performance: golimumab (anti-TNF) reached 25.4% and 19.8%, while guselkumab (anti-IL-23) reached 42.5% and 33.9%, respectively.
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Highly Refractory Subgroup: (Patients with inadequate response to two or more systemic therapies): JNJ-4804's performance was even more striking, with a clinical remission rate nearly double that of the highest comparator and an endoscopic response rate over 60% higher than the control.
2. DUET-UC (Ulcerative Colitis) Data:
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Overall Population: At Week 48, the JNJ-4804 clinical remission rate reached 41.0%, significantly outperforming golimumab (11.5%) and numerically exceeding guselkumab (34.0%).
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Highly Refractory Subgroup: JNJ-4804 showed clinically meaningful improvements in both clinical and endoscopic endpoints compared to monotherapy and placebo. Notably, its clinical remission rate was nearly 60% higher than the closest performing comparator.
Safety Profile: A primary concern for dual-target or combination therapies is whether cumulative immunosuppression increases safety risks, such as infections. However, in both studies, the safety findings for JNJ-4804 remained consistent with the known safety profiles of the monotherapies, with no unexpected safety signals reported.
Next Steps
Based on the overwhelming clinical data and favorable safety profile demonstrated in the Phase 2b DUET series, J&J has officially announced the full-scale launch of the Phase 3 clinical program for JNJ-4804:
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Phase 3 DUET ENCORE-CD: For adults with moderately to severely active Crohn’s disease.
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Phase 3 DUET ENCORE-UC: For adults with moderately to severely active ulcerative colitis.
Milestone Significance
JNJ-4804 is the first and currently only fixed-dose co-antibody designed to provide molecular-level synergy in IBD treatment.
The drug simultaneously targets and blocks the IL-23 and TNF-α pathways. In IBD pathology, the inflammatory cascade is often driven by multiple orthogonal pathways, which is why blocking a single cytokine often fails to achieve long-term control across all patient populations. Dr. Esi Lamousé-Smith, Vice President and Gastroenterology Disease Area Lead at Johnson & Johnson, noted that by concurrently targeting these two core and complementary pathways, JNJ-4804 achieves a synergistic therapeutic approach where "1+1 > 2."
