Pharmacokinetics and tissue penetration of the new fluoroquinolone grepafloxacin.

A single 400-mg oral dose of grepafloxacin (OPC-17116) was given to each of six healthy male volunteers, and the concentrations of the drug in plasma, cantharides-induced inflammatory fluid, and urine were measured over the subsequent 12 h. The mean peak concentration in plasma of 1.5 micrograms/ml was attained at a mean time of 2.0 h postdose. The mean peak concentration in inflammatory fluid of 1.1 micrograms/ml was attained at a mean time of 4.8 h postdose. The mean elimination half-life in plasma was 5.2 h, and that in inflammatory fluid was 12.7 h. The overall penetration into inflammatory fluid was 180.6% (or 133% if one aberrant result from one volunteer is excluded). Recovery of the drug in urine during the first 24 h postdose was 8.3% of the administered dose. Our results indicate that a once- or twice-daily dosage of grepafloxacin should be adequate to treat systemic infections caused by most bacterial pathogens.