Efficacy and pharmacodynamics of gemifloxacin versus levofloxacin in guinea pig pneumococcal pneumonia induced by strains with decreased ciprofloxacin susceptibility.
Quinolone in vivo bactericidal activity was investigated in a guinea pig pneumonia model using three Streptococcus pneumoniae strains with decreasing susceptibility to ciprofloxacin. Treatment regimens resulted in values of AUC(0-24 h) and C(30 min) similar to those of standard oral regimens in human serum. Efficacy was defined as a significant difference in number of viable bacteria in the lungs compared with the control. Ciprofloxacin, levofloxacin and gemifloxacin were effective against the levofloxacin-susceptible strain. Only gemifloxacin achieved a >/=99.9% reduction versus control against the levofloxacin intermediate-resistant strain. Gemifloxacin achieved a 99.69% reduction and was the only quinolone significantly different from the control (P<0.05) against the levofloxacin-resistant strain. Gemifloxacin offers in vivo activity against ciprofloxacin- to levofloxacin-resistant pneumococci.
García-Olmos
M
M
Department of Medical Microbiology, Fundación Jiménez Di;az, Avda. Reyes Católicos 2, 28040, Madrid, Spain.
Parra
A
A
García-Calvo
G
G
Ponte
C
C
Giménez
M J
MJ
Aguilar
L
L
Soriano
F
F
D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D002939:Ciprofloxacin / Q000494:pharmacology*; D015169:Colony Count, Microbial; D024881:Drug Resistance, Bacterial; D024841:Fluoroquinolones; D000077735:Gemifloxacin; D006168:Guinea Pigs; D064704:Levofloxacin; D008168:Lung / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D009287:Naphthyridines / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D015242:Ofloxacin / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D011018:Pneumonia, Pneumococcal / Q000188:drug therapy* / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000254:growth & development; D016019:Survival Analysis
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009287:Naphthyridines; D002939:Ciprofloxacin; D064704:Levofloxacin; D015242:Ofloxacin; D000077735:Gemifloxacin