HMN 2026: How Physician–researcher’s work yields landmark five-year data for Crohn’s disease drug

A physician–scientist and national leader in inflammatory bowel disease at the University of Cincinnati has led the publication of landmark five-year efficacy and safety data for guselkumab, a biologic therapy for moderately to severely active Crohn’s disease.

Anita Afzali, MD, James F. Heady endowed chair, professor of clinical medicine and interim chair of the Department of Internal Medicine within the College of Medicine, served as lead author and global scientific investigator across the full clinical development program, culminating in this five-year analysis of the Phase 2 GALAXI 1 long-term extension study, published May 1, 2026, in Inflammatory Bowel Diseases—the longest follow-up reported to date for an IL-23 p19 inhibitor in Crohn’s disease.

Sustained remission over five years

Crohn’s disease is a chronic, progressive condition affecting approximately 780,000 Americans and is associated with significant morbidity, including a high lifetime risk of surgery. These realities underscore the importance of therapies that induce and sustain remission.

Guselkumab (Tremfya, Johnson & Johnson) is a selective, dual-acting IL-23 p19 inhibitor evaluated in the GALAXI 1 trial in patients with moderately to severely active Crohn’s disease, including those with prior inadequate response to conventional and biologic therapies.

At five years, 97.7% of patients who remained on therapy achieved clinical remission, with all patients in remission corticosteroid-free. Importantly, more than 71% achieved endoscopic response, and more than 51% achieved endoscopic remission—objective markers of mucosal healing that are strongly associated with long-term outcomes. These benefits were observed regardless of prior biologic exposure, highlighting guselkumab’s effectiveness across a broad, often treatment-refractory population.

Collectively, these data points reinforce IL-23-targeted therapy as a durable, disease-modifying approach with sustained clinical and endoscopic benefit.

The safety profile remained consistent with previously established findings, with no new safety signals identified during five years of follow-up.

From clinical trial design to five-year data

Afzali has played a central leadership role across the full guselkumab development program—from early trial design through phase 2, phase 3 and long-term extension studies: induction results published in Gastroenterology (2022), maintenance results published in The Lancet Gastroenterology & Hepatology (2024), confirmatory Phase 3 GALAXI 2 and 3 results published in The Lancet (2025) and now a five-year analysis. This represents a continuous body of high-impact work across leading international journals, aligning with broader departmental efforts to build integrated research platforms that accelerate innovation from bench to bedside.

“Long-term durability and safety remain defining challenges in inflammatory bowel disease,” Afzali said. “These five-year data demonstrate sustained clinical and endoscopic benefit and reinforce the importance of precision, mechanism-based therapies and reflect a broader commitment to advancing translational science that improves long-term patient outcomes.”

This work is complemented by Afzali’s leadership in advancing translational science and research integration across the Department of Internal Medicine, including development of the Inflammation & Immunology Research Consortium (IIRC), a multidisciplinary initiative accelerating discovery, clinical trials and innovation across immune-mediated diseases. She also leads system-wide efforts aligning clinical operations, research and innovation to accelerate patient-centered, translational care models.

Excellence in translational research

Afzali’s leadership in the GALAXI program underscores UC’s role as a national leader in translational gastroenterology and clinical trials. Her work reflects a broader commitment to integrating scientific discovery, multidisciplinary collaboration and health system innovation—advancing care for patients with complex chronic and immune-mediated diseases. The GALAXI 1 study was funded by Johnson & Johnson.

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