Targanta's latest stage product opportunity, oritavancin, is an intravenous agent with potent bactericidal activity against clinical relevant, difficult-to-treat, serious Gram-positive infections. Oritavancin has completed Phase III clinical trials in complicated skin and skin structure infections (CSSSI). Targanta acquired the rights to develop and commercialize oritavancin in December 2005.
Oritavancin is a semisynthetic glycopeptide with some similarities to vancomycin. However, oritavancin offers considerable advantages because it is insensitive to widespread glycopeptide resistance mechanisms in staphylococci and enterococci that undermine the utility of vancomycin. Preclinical pharmacodynamic studies have shown oritavancin to possess concentration-dependent bactericidal activity, a prolonged post-antibiotic effect and synergy with both β-lactams and aminoglycosides. Two large multicenter Phase III clinical trials with oritavancin have been completed and they demonstrated the drug to be safe and effective in treating CSSSI. An exceptionally long tissue half-life of oritavancin and its favorable distribution, including the ability to penetrate lung tissue, should allow for convenient daily dosing.
Targanta intends to file an NDA in late 2007. Clinical studies and NDA filings are planned for the ensuing three years for additional indications, including catheter-related bacteremia and nosocomial pneumonia.