UPMC Gastroenterologist Carl Samaha, MD, Presents Multiple Abstracts on Crohn’s Disease Research at ACG 2025 Annual Meeting

At the American College of Gastroenterology (ACG) 2025 Annual Meeting held Oct. 24 to 29, in Phoenix, Ariz., postdoctoral fellow Carl Samaha, MD, presented three research abstracts related to Crohn’s disease, one of which was accepted for oral presentation and designated as a “newsworthy abstract” by ACG.

Dr. Samaha is currently a postdoctoral fellow in the lab of Richard H. Duerr, MD, professor of medicine in the UPMC Division of Gastroenterology, Hepatology and Nutrition; Inflammatory Bowel Disease Genetic Research Endowed Chair; and codirector and scientific director of the UPMC Inflammatory Bowel Disease Center.

About the Research

All three abstracts presented by Dr. Samaha and colleagues focus on Crohn’s disease and are exploring aspects of symptom burden and treatment response in patients with nonsymptomatic, mild, or treatment-refractory disease. The research Dr. Samaha and colleagues are working on is designed to better understand limitations of current disease activity measures, factors contributing to persistent symptoms despite mucosal healing, and the durability of biologic therapy in real-world practice.

Abstract Title: Should Clinical Indices Be Used to Screen Symptomatic Patients with Endoscopically Quiescent Crohn’s Disease?

In this study, Dr. Samaha and colleagues are evaluating whether commonly used clinical indices accurately reflect symptom burden in patients with Crohn’s disease who show little to no evidence of active disease as seen in endoscopic evaluation. In their analysis, although all patients met the criteria for endoscopic remission or near-remission, many patients reported ongoing gastroenterological symptoms that led to visits to the emergency department or a hospital admission, and other quality of life measures negatively impacted by their symptoms.

Dr. Samaha and colleagues also found that standard clinical indices identified only a small proportion of these patients as having active disease. Use of the Crohn’s Disease Activity Index was found to be the least sensitive measure. This ongoing research points to a finding that traditional clinical indices frequently are unable to identify patients with meaningful functional impairment when their endoscopic findings otherwise suggest their symptoms ought to be under control.

Abstract Title: Does Mild Endoscopic Disease Drive Persistent Symptoms in Crohn’s Disease? A Repeated Measures Analysis

Accepted for oral presentation and designated as a newsworthy abstract by ACG at the 2025 annual meeting, this study from Dr. Samaha and colleagues examined whether mild residual inflammation explains the presence of persistent symptoms in patients with Crohn’s disease. This analysis is based on longitudinal data from patients at UPMC enrolled in the Study of a Prospective Adult Research Cohort with IBD (SPARC IBD) who showed no symptoms or mildly active disease. Dr. Samaha and colleagues looked at the relationship between low-grade endoscopic findings and patient symptoms, including abdominal pain, urgency, and increased stool frequency. Their analysis showed that mild-appearing disease on endoscopic findings was not associated with the presence or severity of symptoms. Another important finding from the analysis was that female sex was consistently associated with greater symptom persistence across multiple analytic measures.

What this translates to from a clinical impact perspective is that ongoing symptoms in this population of people with Crohn’s disease are not fully explained by mild mucosal inflammation and that a more individualized approach to evaluating patient symptoms is needed, particularly for women given their higher longitudinal symptom burden.

Abstract Title: Real-World Drug Persistence and Clinical Effectiveness of Ustekinumab after Dual Anti-TNF Failure in Crohn’s Disease

In this study, Dr. Samaha and colleagues evaluated treatment persistence and clinical outcomes in patients with Crohn’s disease who began using the biologic therapy, ustekinumab, after failing to achieve disease control with two or more antitumor necrosis factor (anti-TNF) therapies. The patient cohort analyzed in this study was characterized by complex disease features, including high rates of stricturing or fistulizing disease and prior surgical resection.

Patient adherence to ustekinumab therapy remained high between year one (90%) to year three (70%) and among patients who continued ustekinumab, most were able to realize clinical and endoscopic remission of their disease. However, looking at longer follow-up at six years, Dr. Samaha and colleagues found that only 43% of patients remained on therapy but they were still achieving high rates or remission or endoscopically visible remission.

Overall, the findings of this analysis from Dr. Samaha and colleagues indicate that ustekinumab can and does give patients durable clinical and endoscopic benefit and disease control after dual anti-TNF failure. However, it is challenging for many patients to remain on the agent over a long period of time.