Strong in vivo data for Targanta's oritavancin

The USA's Targanta Therapeutics has reported in vivo data from a study comparing the activity of its antibiotic drug candidate, oritavancin, to vancomycin in a hamster model of Clostridium difficile infection.

Presented at the 48th annual Interscience Conference on Antimicrobial Agents and Chemotherapy in Washington DC, USA, the study showed that oritavancin activity at 10mg/kg, 50mg/kg and 100mg/kg/day and a pegylated (PEG400) formulation of oritavancin at 100mg/kg/day were compared to vancomycin activity at 50mg/kg/day against clindamycin-induced C. difficile infection in Golden Syrian hamsters, which is a widely recognized model for this type of infection.

According to Targanta, all doses of oritavancin were highly-effective in prolonging survival compared to untreated controls, and prevented relapse longer than treatment with vancomycin at equivalent dose. Oritavancin at 100mg/kg exhibited superior efficacy to vancomycin at day 12: 100% survival was observed for animals treated with oritavancin compared to 0% survival with vancomycin. The PEG400 formulation of oritavancin protected all hamsters from relapsing, yielding 100% survival out to day 20, compared to vancomycin (0% survival).