Cefteram pivoxilのbioavailabilityに及ぼす併用薬物の影響

抄録

Cefteram has a broad antibacterial spectrum against gram-positive and gram-negative bacteria, and its antibacterial activity has been reported to be superior to other oral cephalosporins. Cefteram pivoxil, a new prodrug of cefteram for oral administration, is expected to be hydrolyzed to cefteram by esterase in the gastrointestinal tract. It has been reported that the bioavailability of cefteram pivoxil was influenced by food intake, and amounts of the drug excreted in urine within 8 hr after dosing were 33% in a nonfasted group and 18% in a fasted group.The gastrointestinal absorption of many drugs has been shown to be altered by concomitantly administered antacids. In the present study, the bioavailability of cefteram pivoxil was examined by regimens allowing postprandial administration of the drug with and without the concomitant administration of dried aluminum hydroxide gel, an antacid, or aclatonium napadisilate, a stimulant of gastrointestinal smooth muscle activity and an accelerator of gastric emptying, in 5 healthy subjects. In this study, the mean cefteram serum concentrations after single oral administration of 200 mg of cefteram pivoxil were shown to be the same among the three examined groups. We found that t_max was 2.9±0.4 hr (mean±SEM) without any coadministered drug, 2.7±0.3 hr with coadministration of dried aluminum hydroxide gel, and 2.7±0.4 hr with coadministration of aclatonium napadisilate. C_max was 2.8±0.1, 2.9±02, and 2.8±0.3μg/ml, and AUC_0-∞ was 10.1±0.8, 9.8±0.7, and 9.6±1.0 (μg/ml) ·hr, for control, with the antacid, and with aclatonium napadisilate, respectively. These values were not significantly different. Thus bioavailability of cefteram pivoxil was not altered by concomitantly administered dried aluminum hydroxide gel or aclatonium napadisilate after a meal. The bioavailability of cefteram pivoxil was not influenced by coadministered drugs, probably because this study was performed after a meal.