Bezlotoxumab in an Academic Urban Clinical Practice: A Case Series of 18 Months of Use

Abstract

Introduction: In October of 2016 the FDA approved bezlotoxumab for the treatment of recurrent Clostridium difficile infections (CDI). Bezlotoxumab is a human monoclonal antibody which binds to toxin B neutralizing its effects. In MODIFY 1 and MODIFY 2, large randomized trials, bezlotoxumab showed clinical significance over placebo in preventing recurrence of CDI. We present a case series representing the first 18 months of this medications use in an urban, academic clinical institution. Description: We reviewed 4 patient cases where bezlotoxumab was used between April 2017 and April 2018. Patients included were highly complex including a patient post liver transplant and Crohn's disease patient both on chronic immunosuppression. The patients each had multiple recurrences of CDI and 3 were treated with at least 2 different antibiotics, 1 patient was unable to tolerate metronidazole or vancomycin only received fidaxomicin prior to infusion. All patients received standard weight based 10mg/kg dosing coinciding with antibiotic therapy (2 with vancomycin, 2 with fidaxomicin). No adverse events were experienced during or post infusion. Following treatment improvement in symptoms was documented in each case and 3 out of 4 patients were CDI free for greater then 12 weeks, the standard set by the MODIFY trials. Three patients had documented recurrence of CDI at 217, 90, and 64 days. Average time to recurrence was 123 days. The fourth patient had no recurrence at 160 days. Discussion: Bezlotoxumab is a promising treatment for recurrent CDI, however clinical experience is still early and limited. Our review of the first 18 months of clinical use at an academic medical center show it has been successful in preventing CDI recurrence at 12 weeks+ with average time to recurrence of 123 days. Our patient population was complex similar to a minority of patients in the MODIFY trials. Despite 3 of the 4 patients experiencing recurrence all received clinical benefit. Recurrence likely represents re-infection in individuals with multiple risk factors for CDI. Based on this initial experience from clinical use bezlotoxumab appears to be a safe and effective treatment in the treatment of recurrent CDI including in medically complex patients.1510 Figure 1 No Caption available.