Clostridium difficile infection (CDI) is the most common nosocomial infection in 
the U.S. 25% of CDI patients go on to develop recurrent CDI (rCDI) following 
current standard of care (SOC) therapy, leading to morbidity, mortality and 
economic loss. The first passive immunotherapy drug targeting C.difficile toxin 
B (bezlotoxumab) has been approved recently by the FDA and EMA for prevention of 
rCDI. Areas covered: A body of key studies was selected and reviewed by the 
authors. The unmet needs in CDI care were ascertained with emphasis in rCDI, 
including the epidemiology, pathophysiology and current management. The current 
knowledge about the immune response to C. difficile toxins and how this 
knowledge led to the development and the clinical use of bezlotoxumab is 
described. Current and potential future competitors to the drug were examined. 
Expert commentary: A single 10 mg/kg intravenous infusion of bezlotoxumab has 
been shown to decrease rCDI by ~40% (absolute reduction ~10%) in patients being 
treated for primary CDI or rCDI with SOC antibiotics. Targeting C.difficile 
toxins by passive immunotherapy is a novel mechanism for prevention of 
C.difficile infection. Bezlotoxumab will be a valuable adjunctive therapy to 
reduce the burden of CDI.