Liquid chromatographic determination of ceftibuten, a new oral cephalosporin, in human plasma and urine

Development and Validation of UPLC Tandem Mass Spectrometry Assay for Ceftibuten and Sulbactam in Human Plasma

A sensitive and rapid ultra-performance liquid chromatography coupled with -tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine ceftibuten (CTB) and sulbactam (SUL) in human plasma. An ACQUITY UPLC HSS T3 C18 (2.1 × 100 mm), 1.8 μm column with gradient elution of water (0.1% formic acid) and acetonitrile was used for separation at a flow rate of 0.2 mL/min. This method involves a simple sample preparation with acetonitrile. The calibration curves of CTB and SUL in plasma showed good linearity over the concentration range of 0.50-25 μg/mL and with a correlation coefficient (r2) >0.99. This method was validated in terms of selectivity, linearity, precision, accuracy and stability. High precision was obtained with coefficients of variation <15%. Excellent recovery in the range of 90-104% was achieved for CTB and SUL was 86-110%. The method has the potential utility to support pharmacometric modeling in clinical practice and biopharmaceutic studies.

Analysis of cephalosporin antibiotics

A comprehensive review with 276 references for the analysis of members of an important class of drugs, cephalosporin antibiotics, is presented. The review covers most of the methods described for the analysis of these drugs in pure forms, in different pharmaceutical dosage forms and in biological fluids.

Comparison of ceftibuten transport across Caco-2 cells and rat jejunum mounted on modified Ussing chambers

Ceftibuten uptake into Caco-2 cells and intestinal brush border membrane vesicles is mediated by the dipeptide transport system (PEPT1). The apical to basolateral transport characteristics of ceftibuten across Caco-2 cells and rat jejunum mounted on a modified Ussing chamber was examined. Mannitol was used as a paracellular marker along with trans-epithelial electrical resistance (TEER) for monitoring tight junction permeability. Transport across Caco-2 cells and rat jejunum mounted on a modified Ussing chamber was linear across the concentration range 0.25-10 mM. The net flux of mannitol and ceftibuten was higher across rat jejunum compared with Caco-2 cells. At a donor concentration of 0.25 mM, ceftibuten transport across Caco-2 cells was found to be pH dependent. Glycyl proline, a dipeptide, and 2,4- dinitrophenol, an energy poison, caused a reduction in the permeability of 0.25 mM ceftibuten across Caco-2 cells. Benzoic acid and adipic acid also inhibited transcellular transport of ceftibuten. At a donor concentration of 0.25 mM, passive paracellular transport accounts for about 60% and the active carrier mediated mechanism accounts for about 40% of ceftibuten transport across Caco-2 cells. None of the inhibitors however, had a significant effect on ceftibuten transport across rat jejunum mounted on a modified Ussing chamber at a donor concentration of 0.25 mM. In the concentration range 0.25-10 mM, ceftibuten is predominantly transported by paracellular mechanisms across rat jejunum and a mixture of active and passive transport across Caco-2 cells.

Transporters involved in apical and basolateral uptake of ceftibuten into Caco-2 cells

Ceftibuten uptake from the apical and basolateral side of Caco-2 cells grown on transwells was studied. Uptake into the cells showed concentration dependent saturation. The apical transporter(s) showed a higher capacity and lower affinity for ceftibuten than the basolateral transporter(s). Uptake was inhibited in the presence of higher pH and in the presence of 2,4-dinitro phenol (DNP). A proton gradient had a greater effect on the apical than on the basolateral transporter. Glycyl proline, a dipeptide transport system (PEPT1) substrate, inhibited ceftibuten uptake into Caco-2 cells. Benzoic acid, a monocarboxylic acid (MCT) transporter substrate also exhibited a strong inhibition of ceftibuten uptake, but acetic acid had no effect. Adipic acid inhibited apical uptake of ceftibuten but had no effect on the basolateral uptake. None of the inhibitors had a significant effect on ceftibuten uptake in absence of a pH gradient. Addition of inhibitors in presence of DNP led to a greater decrease in ceftibuten uptake, when compared to the effect of DNP alone, indicating a facilitated diffusion process. These results indicate that ceftibuten uptake in Caco-2 cells involve multiple transport pathways. Apical uptake is mediated by an energy dependent carrier-mediated process and an energy independent facilitated diffusion process. The apical transport system is different from the basolateral transporter.

Analysis of recent antimicrobial agents in human biological fluids by high-performance liquid chromatography

Our previous review on the liquid chromatographic (LC) analysis of anti-bacterial agents was published in 1990 in a special issue of the Journal of Chromatography. Eight years later, some new agents have been registered and numerous other are under clinical experiment. In spite of therapeutic problems encountered with certain bacterial pathogens, the development of novel drug candidates has slowed partially due to the need for identification of new bacterial targets and the cost of the research. The present overview updates the LC methods for the quantitations of recent antimicrobial agents (marketed and in clinical development) in human biological fluids. Consideration has been given to procedures permitting the determination of isomers and metabolites as well as methods regarding tissue extracts or liquid sampled from physiological sanctuaries. LC methods are available for the quantitation of almost all registered or investigated recent anti-infective drugs and some are applicable in routine practice. Nevertheless, few techniques have been validated for the determination in tissue extracts limiting the development of penetration studies.

Ceftibuten: a new expanded-spectrum oral cephalosporin

OBJECTIVE

To review the antimicrobial activity, pharmacokinetics, clinical efficacy, and tolerability of ceftibuten, a new expanded-spectrum oral cephalosporin.

DATA SOURCES

Literature was identified by a MEDLINE search (January 1983-June 1996) of the medical literature, review of English-language literature and bibliographies of these articles, and data on file.

STUDY SELECTION

Clinical efficacy data were selected from all published and unpublished trials and abstracts that mentioned ceftibuten. Additional information concerning in vitro susceptibility, safety, chemistry, and pharmacokinetic profile of ceftibuten also was reviewed.

DATA SYNTHESIS

Ceftibuten, an oral expanded-spectrum cephalosporin, has a broad spectrum of activity against many gram-negative and selected gram-positive organisms, including Streptococcus pneumoniae, Streptococcus pyogenes, Moraxella catarrhalis, and Haemophilus influenzae. Ceftibuten is stable to hydrolysis by many common beta-lactamases. Ceftibuten is rapidly and almost completely absorbed from the gastrointestinal tract and is primarily eliminated renally as unchanged drug. The elimination half-life of ceftibuten is slightly longer than 2 hours. Efficacy has been demonstrated in a number of clinical trials in adults and children with upper and lower respiratory tract infections (e.g., acute otitis media, pharyngitis, sinusitis, bronchitis) and urinary tract infections. The adverse effect profile is equal to that of comparator agents.

CONCLUSIONS

Ceftibuten is an alternative to other antimicrobial agents with convenient once-daily dosing in the treatment of upper and lower respiratory tract infections. Similar to other oral expanded-spectrum cephalosporins, ceftibuten has antimicrobial activity against common pathogens of the respiratory tract and is stable in the presence of many beta-lactamases. The clinical choice of an oral expanded-spectrum cephalosporin will be based on patient acceptance, frequency of administration, and cost.

Pharmacokinetics and dose proportionality of ceftibuten in men

The pharmacokinetics and dose proportionality of ceftibuten were evaluated in healthy male volunteers receiving single oral doses of 200, 400, and 800 mg of ceftibuten. The drug was absorbed with similar times to the maximum concentration of drug in plasma for all three doses. Concentrations of ceftibuten in plasma increased with increasing dose. Analysis of variance was carried out on the dose-adjusted values for the maximum concentration of drug in plasma and the area under the plasma concentration-time curve; the results indicated that the concentrations in plasma after the 200- and 400-mg doses were dose proportional, and after the 800-mg of dose they were less than dose proportional. The elimination half-life from plasma ranged from 2.0 to 2.3 h and was independent of dose. The total excretion of unchanged ceftibuten in urine accounted for 53 to 68% of the dose, and the renal clearance was estimated to be 53 to 61 ml/min after all doses. The amount of ceftibuten-trans, the major in vitro and in vivo conversion product of ceftibuten, was low in both plasma and urine.