Merck carried out the MODIFY I study in 19 countries participated by more than 1,400 patients with a median age of 65. MODIFY II study had over 1,200 participants with an average age of 67 and living in 17 countries.
Patients in both groups received an administration of antibiotics, along with a one-time infusion of bezlotoxumab, a combination of bezlotoxumab and actoxumab, or a placebo, for a period of 12 weeks.
The combination of antibiotics and a single infusion of bezlotoxumab lowered the risk of recurrence to 15%. The recurrence among patients with placebo was 25%.
Merck said treatment with the combination of bezlotoxumab and actoxumab did not offer added efficacy over bezlotoxumab alone.
Actoxumab alone provided no benefit in the prevention of C. difficile recurrence versus placebo. Based on the results, The company selected bezlotoxumab for the marketing authorization application.
Merck is planning to submit new drug applications in the US, European Union and Canada later this year.
The company secured the license for using bezlotoxumab in development as a potential therapeutic for C.difficile infection in 2009. It was developed by the University of Massachusetts Medical School’s MassBiologics Laboratory and Medarex (which is currently under Bristol-Myers Squibb).
The incidence of C. difficile infection has increased rapidly in the last two decades. According to the US Centers for Disease Control and Prevention (CDC), C. difficile is expected to have caused around half a million infections in the US in 2011.
About 29,000 deaths were reported to be occurred within 30 days of initial diagnosis.