Pharmacokinetics and safety of ascending single doses of DZ-2640, a new oral carbapenem antibiotic, administered to healthy Japanese subjects.
DZ-2640 is the ester-type oral carbapenem prodrug of an active parent compound, DU-6681. The pharmacokinetics and safety of DU-6681 were investigated in six studies after oral administration of a single dose of DZ-2640 to healthy male Japanese volunteers at doses of 25, 50, 100, 200, and 400 mg (as the equivalents of DU-6681) in the fasted state. The same volunteers received the drug at a dose of 100 mg in the fasted and fed states to examine the effect of food intake on the bioavailability of DZ-2640. The concentrations of DU-6681 in plasma and urine were determined by a validated high-performance liquid chromatography method and a bioassay. A good correlation between both methods was seen, indicating an absence of major active metabolites. The mean maximum concentrations of DU-6681 in plasma (C(max)) ranged from 0.263 microgram/ml (25-mg dose) to 2.489 microgram/ml (400-mg dose) and were reached within 1.5 h following drug administration. After reaching the C(max), plasma DU-6681 concentrations declined in a monophasic manner, with a half-life of 0.47 to 0.89 h. The area under the concentration-time curve (AUC) and C(max) increased almost linearly with the dose up to the 200-mg dose. The AUC and C(max) increased less than proportionally after administration of the 400-mg dose, suggesting a reduction in drug absorption. The plasma protein binding of DU-6681 was in the range of 23.3 to 25.6%. The cumulative urinary recoveries (0 to 24 h) were in the range of 31.9 to 44.9%. The AUC was slightly but statistically significantly reduced by food intake. However, the C(max), half-life, and recovery in urine were not affected by food intake. The renal clearance (402 to 510 ml/min) was much greater than the mean glomerular filtration rate (ca. 120 ml/min), which indicated active tubular secretion of the drug. A mild transient and moderate diarrhea was observed in two of six volunteers in the study with a single dose of 25 mg. Mild soft stools were observed in two of six volunteers who received a 400-mg dose of the drug.
Tanaka
M
M
Drug Metabolism and Analytical Chemistry Research Laboratory, Daiichi Pharmaceutical Co. Ltd., Edogawa-ku, Tokyo 134-8630, Japan. LDP04207@nifty.ne.jp
Kato
K
K
Hakusui
H
H
Murakami
Y
Y
Sato
K
K
Ito
Y
Y
Kawamoto
K
K
D001681:Biological Assay; D001798:Blood Proteins / Q000378:metabolism; D015780:Carbapenems / Q000008:administration & dosage / Q000009:adverse effects* / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D004311:Double-Blind Method; D006801:Humans; D007564:Japan; D008297:Male; D011485:Protein Binding
D001798:Blood Proteins; D015780:Carbapenems; C106855:DZ 2640