Cefditoren Sodium Salt

Cefditoren, a third generation cephalosporin antibiotics, has been used in clinics extensively. Previous results have indicated that cefditoren is excreted into bile as unchanged form. To investigate whether canalicular membrane transporters of hepatocytes were involved in the biliary excretion of cefditoren, we examined the hepatobiliary disposition of cefditoren using probenecid, novobiocin and verapamil as inhibitors of Mrp2, Bcrp and P-gp respectively in perfused rat livers. The values for the hepatic extraction ratio had no statistical significance, whereas cumulative biliary excretion rates of cefditoren were significantly reduced to 43.8% and 79.5% over 25 min in the perfused probenecid and novobiocin rats, respectively. We further investigated the effects of cefditoren on the expression of hepatic transporters by RT-PCR and Western blot after oral administration of cefditoren one week. The expression levels of Mrp2, Bcrp, Oat2 mRNA were markedly increased, while P-gp and Oct1 mRNA were decreased.

The evaluation of seven widely-used antibiotic preparations [five cephem antibiotics; cefaclor (CCL), cefpodoxime proxetil (CPDX-PR), cefdinir (CFDN), cefditoren pivoxil (CDTR-PI), cefcapene pivoxil (CFPN-PI), one macrolide; clarithromycin (CAM) and one penem; faropenem sodium (FRPM)] for children were performed from a standpoint of water-solubilities, both as a preparation and as a component drug. As the results, these preparations showed great differences in the water-solubilities when added 10 ml water to 0.5 g of each preparation. That is, their solubilities differed from about 40% (CFPN-PI) to 100% (FRPM) as a preparation, and from nearly 0% (CAM) to 100% (FRPM, CCL) as a component drug. Additionally, about a half of the insoluble residues were found to be the component drug, in the cases of three preparations (CPDX-PX, CFDN, CDTR-PI) which were solubilized at 80-90%. From these results, it was suggested that the marketed antibiotic preparations for children might be classified into three categories; i.