Lindsey C. Shipley, MD1, Sujan Ravi, MD1, Kirk Russ, MD1, Frederick H. Weber, Jr., MD2; 1University of Alabama, Birmingham, AL; 2UAB, Birmingham, AL
Introduction: Microscopic colitis (MC) is characterized by chronic watery diarrhea, histologic inflammatory or collagenous abnormalities and a lack of endoscopic findings. Clinical response to bile acid sequestrants and/or budesonide is typical and corticosteroid failures occur very infrequently. We report the largest prospective study in the United States evaluating clinical response to vedolizumab in corticosteroid-refractory or intolerant patients with MC. Methods: Adult patients with refractory MC treated with vedolizumab at a tertiary care center in the southeastern United States were included. Refractory MC was defined as persistent symptoms despite trials of current approved therapies. Vedolizumab IV induction infusions were given at 0, 2 and 6 weeks followed by maintenance dosing every 8 weeks. Clinical response to therapy was closely monitored during induction to assess time to clinical response ( > 50% improvement in stool frequency) and clinical remission (3 or less bowel movements per day with improved consistency). Results: Eight patients (6 female, median age 53 yrs.) with refractory MC (2 collagenous, 3 lymphocytic, 1 collagenous and lymphocytic, 2 MC incomplete) and median symptom duration prior to vedolizumab treatment of 7.5 years were included in the case series. In addition to budesonide (n=8), failed therapies included bile acid sequestrants (n=8), mesalamine (n=2), prednisone (n=2), bismuth (n=1), adalimumab (n=1) and 6-mercaptopurine (n=2). Clinical response with vedolizumab induction was observed in 7 (87.5%) patients. Time to clinical response after initial induction infusion initiation was week 1 (n=3), week 3 (n=2) and week 7 (n=2). Clinical remission was attained in 6 (75%) patients. One patient lost response after transitioning to maintenance and one had insufficient response to induction therapy. Discussion: This is the first United States prospective case series and the world’s largest single center series reported to date of vedolizumab therapy in patients with refractory MC. Vedolizumab led to sustained clinical improvement in the majority of patients. Clinical response appears to be rapid and durable in the short term in most patients with a well-established safety profile. This case series significantly advances the existing limited literature regarding treatment of refractory MC. Vedolizumab shows great promise as therapy for refractory MC, but further randomized controlled trials which include histologic reassessment and long-term durability of response are needed.
Disclosures: Lindsey Shipley indicated no relevant financial relationships. Sujan Ravi indicated no relevant financial relationships. Kirk Russ indicated no relevant financial relationships. Frederick Weber indicated no relevant financial relationships.