Pharmacokinetic parameters for (+) and (−) enantiomers of gemifloxacin following administration of racemic gemifloxacin mesylate to the rat and the dog
Oral | Intravenous | |||
---|---|---|---|---|
(+) Enantiomer | (−) Enantiomer | (+) Enantiomer | (−) Enantiomer | |
Rat | ||||
C max(ng/ml) | 158 ± 43 | 139 ± 32 | 1200 ± 174 | 974 ± 109 |
T max(h) | 1.3 | 1.3 | N.A. | N.A. |
AUC (ng · h/ml)2-a | 715 ± 107 | 640 ± 87 | 2240 ± 255 | 1970 ± 269 |
T 1/2 (h) | 2.0 ± 0.5 | 2.0 ± 0.4 | 1.5 ± 0.2 | 1.6 ± 0.1 |
CLb(l/h/kg) | N.D. | N.D. | 1.2 ± 0.1 | 1.4 ± 0.2 |
Vss (l/kg) | N.D. | N.D. | 3.8 ± 0.5 | 4.8 ± 0.6 |
F (%) | 11 ± 2 | 11 ± 2 | N.A. | N.A. |
Dog | ||||
C max (ng/ml) | 660 ± 260 | 710 ± 290 | 2480 ± 240 | 2740 ± 320 |
T max(h) | 1.5 | 1.5 | N.A. | N.A. |
AUC (ng · h/ml)2-a | 4760 ± 2590 | 4600 ± 2660 | 6650 ± 1160 | 6770 ± 1210 |
T 1/2 (h) | 5.6 ± 1.6 | 5.0 ± 2.0 | 5.0 ± 0.9 | 4.7 ± 0.8 |
CLb(l/h/kg) | N.D. | N.D. | 0.4 ± 0.1 | 0.4 ± 0.1 |
Vss (l/kg) | N.D. | N.D. | 4.4 ± 1.1 | 4.0 ± 0.8 |
F (%) | 60 ± 36 | 57 ± 34 | N.A. | N.A. |
Racemic gemifloxacin mesylate was administered orally at 30 and 10 mg of fb/kg to the rat and dog, respectively, and intravenously at 10 mg of fb/kg to both species. Data are mean values ± S.D. (n = 3–4) except for Tmax, which are median values.
N.A., not applicable; N.D., not determined;Cmax, maximum concentration;Tmax, time to reach maximum concentration;T1/2, apparent terminal phase elimination half-life; CLb, blood clearance; F, bioavailability.
↵2-a AUC (0–inf).