Merck & Co Inc has developed an antibody that may reduce the risk of a deadly diarrhea recurrence caused by Clostridium difficile (C. difficile) by at least 15%.
The company has announced on Sunday, Sept 20, in San Diego that is already has some results for its phase 3 study, which aims to assess the effectiveness of the antitoxin bezlotoxumab used alone or in combination with actoxumab, another antibody, when compared to the placebo.
Bezlotoxumab works by binding with toxin B of the bacteria, which can cause the inflammation of the gut, which then results to watery diarrhea and abdominal pain, some of the most common symptoms of the infection. Actoxumab, on the other hand, works against toxin A of the same bacteria.
The double-blind studies were labeled as MODIFY I and MODIFY II. MODIFY I was conducted in 19 countries and participated by more than 1,300 patients with a median age of 65. MODIFY II had at least 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 decreased the risk of recurrence to 15%. On the other hand, the recurrence among patients with placebo was 25%. 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 are the same for both placebo and treatment.
The company is now moving into filing an application for its regulatory approval before the year ends. The antibody bezlotoxumab is developed by Medarex (which is now under Bristol-Myers Squibb) and Massachusetts Biologic Laboratories.
C. difficile infections, which are normally acquired in medical settings, affect at least 500,000 people in the United States and kill 29,000, many of whom succumbed within 30 days of infection. Elderly patients who are receiving antibiotic care are the most vulnerable.
