Bezlotoxumab (Zinplava)
Bezlotoxumab (Zinplava™) was added to the Nebraska Medicine formulary with restriction to the infusion center. Bezlotoxumab is a human monoclonal antibody approved by the FDA in October 2016 to reduce the recurrence of Clostridium difficile infection (CDI) in patients 18 years of age or older who are receiving antibacterial drug treatment of CDI and are at a high risk for CDI recurrence. The agent binds toxin B and blocks its activity. The MODIFY I and II trials assessed the efficacy and safety of bezlotoxumab. In both studies, bezlotoxumab was superior to placebo in prevention of CDI recurrence over 12 weeks (p=0.0003 for MODIFY I and II) and had a safety profile similar to placebo. Recurrence rates with bezlotoxumab were 17.4% and 15.7% in MODIFY I and II, respectively compared to 26.7% and 25.7%, respectively with placebo.
Dosing
Bezlotoxumab is provided as a single dose of 10 mg/kg infused intravenously over 60 minutes.
Safety
Side effects were rare and usually mild (nausea, headache, fever) but some question of increased risk of heart failure was noted and use in patients with a history of heart failure should be limited situations where benefit outweighs risk.
A comparison of bezlotoxumab to fecal microbiota transplant has not been performed. Nebraska Medicine C. difficile infection guidelines address the potential roles for both these options in CDI prevention.