P2611 - A Retrospective Study of Treatment Options for Checkpoint-Inhibitor Colitis and Their Impact on Disease Outcomes

Malek Satila, MD¹, Andres Rivera, MD², Kian Abdul-Baki, DO³, Kei Takigawa, MD², Tanvi Gupta, MD⁴, Elliot Axel. Baerman, MD², Linfeng Lu, MD², Irene J. Lee, MD², Hamza Salim, MD³, Carolina Colli Cruz, MD¹, Raakhi Menon, DO³, Andrew Sullivan, MD⁵, Varun Vemulapalli, MD⁴, Cristina M. Natha, MD⁴, Ayesha Khan, DO³, Garrett T. Coleman, ⁶, Krishnavathana Varatharajalu, MD⁷, Yinghong Wang, MD, PhD^8
1MD Anderson Cancer Center, Houston, TX; ²Baylor College of Medicine, Houston, TX; ³University of Texas Medical Branch, Galveston, TX; ⁴University of Texas Health, McGovern Medical School, Houston, TX; ⁵University of Texas Health Science Center, Houston, TX; ⁶University of Texas Medical Branch, John Sealy School of Medicine, Galveston, TX; ⁷The University of Texas MD Anderson Cancer Center, Houston, TX; ⁸University of Texas MD Anderson Cancer Center, Houston, TX

Introduction: Immune-mediated colitis (IMC) is a debilitating medical condition secondary to immune-checkpoint inhibition. It is similar to inflammatory bowel disease (IBD) and most of its treatments have been adapted from IBD practice. Selective immunosuppressive therapy (SIT) and fecal microbiota transplantation (FMT) are two especially popular treatment options. Few studies in the literature with large sample sizes directly compare the efficacy of the different treatments used to manage this disease. Our study aims to describe the clinical features of IMC in our institutional cohort and compare the outcomes of different types of treatment.

Methods: : This was a single center, retrospective review including all patients who received immune checkpoint inhibitors between January 2010 to February 2024 and developed IMC. Patients were screened for immune-mediated colitis based on stool tests, then divided into two subgroups based on the treatments they received (i.e. infliximab vs. vedolizumab and SIT vs. FMT subgroups). We collected data on patient demographic information and colitis clinical information including presentation, endoscopic features, treatments, and outcomes. SPSS 26.0 was used to analyze the data.

Results: A total of 1,152 patients met the study criteria, 465 (40.4%) received SIT (177 infliximab, 258 vedolizumab) alone and 62 (5.4%) received FMT. The majority of patients present with grade 2 and above diarrhea or colitis with positive stool biomarkers (lactoferrin and calprotectin). Around 80% of cases required ICI discontinuation, with around 35% of patients able to resume immunotherapy. Infliximab and vedolizumab showed similar rates of endoscopic and clinical remission (p >0.05), with vedolizumab-treated patients having shorter symptom durations (p< 0.05). Remission rates between SIT-treated and FMT-treated patients were similar, with around 85% of patients achieving clinical remission and 80% achieving endoscopic remission in both groups (p >0.05).

Discussion: This is the largest study to date reporting the clinical manifestations of immune-mediated colitis and comparing treatment outcomes between different management strategies. We found that infliximab and vedolizumab showed similar efficacy in treating IMC, with vedolizumab leading to shorter symptom durations. SIT and FMT also showed similar clinical and endoscopic remission rates. Prospective trials are crucial to evaluate the safety and efficacy of these treatments.


Disclosures:


Malek Satila, MD¹, Andres Rivera, MD², Kian Abdul-Baki, DO³, Kei Takigawa, MD², Tanvi Gupta, MD⁴, Elliot Axel. Baerman, MD², Linfeng Lu, MD², Irene J. Lee, MD², Hamza Salim, MD³, Carolina Colli Cruz, MD¹, Raakhi Menon, DO³, Andrew Sullivan, MD⁵, Varun Vemulapalli, MD⁴, Cristina M. Natha, MD⁴, Ayesha Khan, DO³, Garrett T. Coleman, ⁶, Krishnavathana Varatharajalu, MD⁷, Yinghong Wang, MD, PhD⁸. P2611 - A Retrospective Study of Treatment Options for Checkpoint-Inhibitor Colitis and Their Impact on Disease Outcomes, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.