Key Phase 3 studies of Bezlotoxumab meet primary end-point

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During the Phase 3 studies, Merck claimed the 12 week treatment plan that included antibiotics and a one-time infusion of bezlotoxumab reduced the recurrence of C. difficile by about 15 percent. The antibody bezlotoxumab when used with antibiotics for 12 weeks was able to prevent reoccurrence of the bacterial infection.

An important new therapeutic for C. difficile infection based on discoveries at UMass Medical School will be submitted for regulatory approval based on the results of clinical studies conducted by the globalpharmaceutical company Merck.

Merck said treatment with the combination of bezlotoxumab and actoxumab did not offer added efficacy over bezlotoxumab alone. MODIFY I was conducted in 19 countries and participated by more than 1,300 patients with a median age of 65. The research discovered that the an infection recurred in about 25 p.c of sufferers handled with antibiotics and a placebo. Recurrence will occur in about one in four C. difficile patients after the initial episode, and 40 percent of these patients will experience further problems.

During the investigation, a single infusion of bezlotoxumab cut down the recurrence of C. difficile infection in a month's time, from 25 percent to 15 percent.

Results from the studies were presented for the first time at the Interscience Conference of Antimicrobial Agents and Chemotherapy (ICAAC) and globalCongress of Chemotherapy and Infection (ICC) joint meeting in San Diego. There's no benefit in taking actoxumab, even if it's combined with bezlotoxumab, and that during the period of the study, the actoxumab arm was stopped for safety and efficacy reasons.

Side effects, which include nausea, urinary tract infections and diarrhea, occurred at rates that were similar for patients in both the treatment and the placebo arms of each trial. Actoxumab alone provided no benefit in the prevention of C. difficile recurrence compared with placebo.

The double-blind studies were labeled as MODIFY I and MODIFY II. These subpopulation analyses were prespecified in study protocols.

Therefore, bezlotoxumab alone was selected for the marketing authorization application.

Incidences of C. difficile have risen dramatically over the past few 20 years, and is believed to have caused almosthalf a million infections in the 2011. People with compromised immune systems particularly those with underlying disease are at risk of developing the infection. Dr. Dale Gerding, another Merck investigator involved in the trials, explained that C. difficile infectious have the bad habit of recurring.


Bezlotoxumab is not an antibiotic, it is a selective monoclonal antibody created to neutralize C. difficile toxin B, which can injure the gut wall and cause inflammation, leading to common symptoms of C. difficile enteritis.