Trovafloxacin in Combination with Vancomycin against Penicillin-Resistant Pneumococci in the Rabbit Meningitis Model

Trovafloxacin, a new fluoroquinolone, produced bactericidal activity (−0.33 ± 0.13 Δlog(10) CFU/ml · h; intravenously [i.v.] administered dose, 15 mg/kg) comparable to that of vancomycin (−0.39 ± 0.18 Δlog(10) CFU/ml · h; i.v. administered dose, 20 mg/kg) in the treatment of experimental meningitis in rabbits due to a pneumococcal strain highly resistant to penicillin (MIC of penicillin G, 4 μg/ml). The combination of both drugs significantly increased (P < 0.05) the killing rate (−0.60 ± 0.23 Δlog(10) CFU/ml · h) compared to that produced by either monotherapy. These results were also confirmed in vitro.