2078 Can Dosing Intervals of Adalimumab Be Increased in Crohn’s Disease?

Abstract

INTRODUCTION: Adalimumab is a recombinant monoclonal antibody that binds to human tumor necrosis factor alpha (TNF-a), thereby interfering with TNF-α receptor sites and cytokine-driven inflammation. There is limited data on de-escalation of adalimumab dosing to intervals greater than every other week (EOW) in Crohn’s disease. We present a case of a young man with Crohn’s who remained in clinical remission on adalimumab de-escalation dosing. CASE DESCRIPTION/METHODS: A 23-year-old man with Crohn’s disease presented to clinic in September 2018 in remission on adalimumab 40 mg every 7 weeks. He initially presented in January 2011 with bloody diarrhea, fever, anemia, leukocytosis and elevated ESR. Colonoscopy revealed a normal small bowel with pancolitis. He started oral budesonide and mesalamine, however due to lack of improvement he required escalation to biologic therapy with infliximab. Several months after initiation, he developed an infusion reaction and was switched to adalimumab. After induction, he went into clinical remission. At each yearly follow up his dosing interval was increased, until 2018 when he was on every 7 week dosing. In October 2018, inflammatory markers were normal and adalimumab level was low but detectable at 1.1 without drug antibodies, so dosing was increased to every 5 weeks. Colonoscopy in February 2019 revealed moderate inflammation in the descending, transverse and ascending colon with a total SES-CD score of 12. He is scheduled to have a repeat adalimumab level drawn before his next infusion. DISCUSSION: Recommended maintenance dosing for adalimumab is 40 mg EOW. Drug levels can vary from one patient to the next. In a retrospective cohort study Van Steenbergen et al. identified 40 patients with Crohn’s who de-escalated adalimumab to every 3 week dosing. At a median follow-up of 24 months, 65% of patients maintained clinical response, and 35% needed dose escalation back to EOW because of relapse, low drug levels, or both1. Our case is the first of a patient maintained in clinical remission, with detectable drug level and no antibody formation on adalimumab at intervals greater than 3 weeks. Given the economic burden of biologic therapy, prolonging the dosing interval of therapy is of interest. More studies are needed to investigate the effects of de-escalation in Crohn’s disease.