Cefroxadine

A specific and rapid high performance liquid chromatographic (HPLC) method with UV detection (254 nm) was developed for the determination of cefroxadine in human plasma. The sample extraction was performed by a simple procedure, vortexing and centrifugation of sample following addition of 60% trichloroacetic acid. Cephalexin was used as an internal standard (I.S.). The HPLC analysis was carried out on a Capcell Pak C18 analytical column with a mobile phase of 50 mM ammonium formate buffer/pH 3.5 and acetonitrile (90:10, v/v). No interference was observed near the peaks of cefroxadine and I.S. The calibration curve was linear over the range of 0.5-40 microg/mL and the lower limit of quantification (LLOQ) was 0.5 microg/mL. The method was validated with excellent sensitivity, accuracy, precision and stability. This assay was successfully applied to determine the pharmacokinetic parameters of cefroxadine in Korean healthy volunteers after an oral administration of two 250 mg cefroxadine capsules.

We compared the antimicrobial activity of commercially available oral cephem agents, cefaclor (CCL), cefroxadine (CXD), cefdinir (CFDN), cefixime (CFIX), cefpodoxime (CPDX), cefteram (CFTM), cefcapene (CFPN), and cefditoren (CDTR), against Streptococcus pneumoniae, Haemophilus influenzae, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, and ESBL-producing bacteria isolated from clinical materials in Kansai Medical University Hospital between 2002 and 2003. Based on the Pharmacokinetics/Pharmacodynamics (PK/PD) theory, we determined the concentration of each agent at which the time above MIC (TAM) value was 40% or more, and calculated the rate of efficacy against each type of bacteria. In S. pneumoniae strains, the MIC(50,80,90) values of CDTR were 0.25, 0.5, and 0.5 microg/ml, respectively, lower than those of the other agents, demonstrating the most potent antimicrobial activity.

Thirteen oral cephems (cefprozil, loracarbef, cefaclor, cefuroxime axetil, cefpodoxime proxetil, cefetamet pivoxil, cefixime, cefdinir, cefadroxil, cephradine, cephalexin, cefatrizine, and cefroxadine), the cephalosporin class representative cephalothin, cefazolin, and the macrolides erythromycin, clarithromycin, and azithromycin were compared for their antibacterial activities against 790 recent clinical isolates. These oral agents differed in their spectra and antibacterial potencies against community-acquired pathogens.