Investigational Antibody Effectively Fights C. Diff Infection

Treatment with the monoclonal antibody bezlotoxumab effectively reduces Clostridium difficile (C. difficile) infection recurrence through week 12 when combined with standard of care antibiotics.

To evaluate bezlotoxumab, either alone or in combination with actoxumab compared to placebo, researchers conducted two Phase 3 double-blind studies.

The MODIFY I study involved 1,452 patients randomized to receive a one-time infusion of bezlotoxumab (10mg/kg) (n=403), actoxumab (10mg/kg) (n=242), or the combination of the two.

The MODIFY II study enrolled 1,203 patients who were randomized to be receive a one-time infusion of bzxlotoxumab (10mg/kg) (n=407), a combination of bezlotoxumab and actoxumab, or placebo.

Results from both of the studies revealed that the rate of C. difficile infection recurrence was significantly lower in the bezlotoxumab group compared to placebo.

It was interesting to note that treatment with a bezlotoxumab and actoxumab combination did not show enhanced efficacy compared with solo bezlotoxumab treatment.

According to Merck, having achieved its primary efficacy endpoint, bezlotoxumab, is now ready for its next stage of development and will soon be submitted to the US Food and Drug Administration (FDA).

Mark Wilcox, MD, Leeds Teaching Hospitals and University of Leeds, UK, presented at the Interscience Conferences of Antimicrobial Agents and Chemotherapy (ICAAC) and International Congress of Chemotherapy and Infection in San Diego, CA, “Results of these studies showed that a single, one-time infusion of the antitoxin bezlotoxumab given with standard of care C. difficile antibiotic treatment significantly reduced the recurrence of C. difficile infection compared to standard of care alone, and demonstrated this benefit over a 12-week period. These results were also demonstrated in patient subgroups known to be at high risk for C. difficile recurrence.”