Comparison of pharmacokinetics and bactericidal activity of teicoplanin and vancomycin

Teicoplanin (0.2 g) or vancomycin (1 g) were infused over 3 and 50 min respectively to six male volunteers in a cross-over study. Each drug was administered twice at a 14 h interval. The pharmacokinetics of both drugs were accurately described using a two-compartment model. Vancomycin had a shorter half-life (5.8 +/- 1.8 h) compared to teicoplainin (33.2 +/- 5.1 h; P less than 0.001). One hour serum was tested for serum bactericidal activity against ten strains each of Staphylococcus aureus (median serum bactericidal activity 1:16 for teicoplanin; 1:32 for vancomycin), Staph. epidermidis (1:32 for teicoplanin and for vancomycin) and Streptococcus faecalis (1:2 for both drugs). Serum killing rate studies showed a slower rate of killing of Staph. aureus with teicoplanin (less than 1 log10 cfu/ml over 6 h) than with vancomycin (4 log10 cfu/ml over 6 h).