Oritavancin (LY-333328), a lead glycopeptide from a series targeted at vancomycin-resistant bacteria, especially enterococci, is under development by Eli Lilly for the potential treatment of bacterial infections. It entered phase III trials in the US in January 2001 [396223] and the company expects to submit an NDA by 2003 [396478]. Oritavancin has been reported to have activity comparable to that of vancomycin and teicoplanin (Aventis Pharma AG), but retains activity against glycopeptide-resistant bacterial strains [407519]. The bactericidal activity of oritavancin suggests that it may prove useful as a single agent therapy in the treatment of antibiotic-resistant enterococci. Although its mechanism of action is unclear, dimerization of the glycosyl portion stabilizing D-Ala-D-Ala binding has been suggested [337644].