Biosearch Italia S.p.A. announced that Genome Therapeutics, its North American licensee for Ramoplanin, has begun a Phase II clinical study of its novel antibiotic Ramoplanin for the treatment of Clostridium difficile-associated diarrhea (CDAD). CDAD is a serious form of colitis caused by toxins produced by the Gram-positive bacteria Clostridium difficile (C.difficile). Ramoplanin has demonstrated in vitro activity against C.difficile, including strains resistant to metronidazole and vancomycin.

The Phase II study, an open-label, three arm multi-center trial, will involve 87 hospitalised patients. One arm will receive Ramoplanin 200 mg twice daily, a second arm Ramoplanin 400 mg twice daily and the third vancomycin, which requires a dose of 125 mg four times daily. Ramoplanin and vancomycin will be administered for ten days. The safety and efficacy results of the Phase II trial will guide the design of the Phase III investigation of Ramoplanin for the treatment of CDAD. Ramoplanin is also being studied in a Phase III trial for the prevention of bloodstream infections caused by vancomycin-resistant enterococci (VRE).

Clostridium difficile-associated diarrhea is the most common form of antibiotic-associated diarrheas in hospital, with approximately 400,000 cases a year reported in the U.S. One study has demonstrated that as many as 20% of hospital patients are colonized with C. difficile either prior to or during admission. C. difficile can colonize the gut and release toxins, leading to bowel inflammation and severe diarrhea. Serious cases can occur and involve the development of fulminant colitis (severe inflammation of the colon).