Lack of in vitro antiviral activity of fluoroquinolones against herpes simplex virus type 2.
The antiviral activity against herpes simplex virus type 2 (HSV-2) of five fluoroquinolones (ciprofloxacin, lomefloxacin, ofloxacin, pefloxacin, rufloxacin) was tested in vitro. Their efficacy was evaluated as reduction of the cytopathic effect (CPER) exerted by HSV-2 on Vero cells in comparison with novobiocin and acycloguanosine. Our results show a very poor antiviral effect of five quinolones (CPER50 = 200 mg/l) that was comparable with their cytotoxicity (TCIC50 less than 200 mg/l). Novobiocin shows a lower toxicity (TCIC50 = 400 mg/l) and a slight antiviral activity (CPER50 = 120 mg/l). Acycloguanosine shows a TCIC50 greater than 400 mg/l and a CPER50 of 3.125 mg/l. The therapeutic indices gave values ranging from 0.12 to 2 for quinolones, of 3.3 for novobiocin, and greater than 128 for acycloguanosine. The antiviral efficacy of acycloguanosine was not affected by concentrations of quinolones active against bacteria (1-10 mg/l) whereas it was drastically reduced by higher doses of quinolones (greater than 50 mg/l). Our data suggest that fluoroquinolones cannot be considered drugs able to inhibit HSV-2 replication in vitro.
Pessina
A
A
Institute of Medical Microbiology, University of Milan, Italy.
Mineo
E
E
Gribaldo
L
L
Neri
M G
MG
D000212:Acyclovir / Q000494:pharmacology; D000818:Animals; D003588:Cytopathogenic Effect, Viral / Q000187:drug effects; D004347:Drug Interactions; D008826:Microbial Sensitivity Tests; D009675:Novobiocin / Q000494:pharmacology; D015363:Quinolones / Q000494:pharmacology*; D018139:Simplexvirus / Q000187:drug effects*; D014709:Vero Cells / Q000187:drug effects
D015363:Quinolones; D009675:Novobiocin; D000212:Acyclovir