Case Study: Vantin: A Prodrug of Cefpodoxime
Cefpodoxime proxetil is an ester prodrug of the extended spectrum antibiotic cefpodoxime, developed by Sankyo Co., Ltd, Japan. It was designed to overcome the poor oral bioavailability of the parent drug. Cefpodoxime (pKa ∼2.20 ± 0.10) exists predominantly in the ionic form at intestinal pH and thus exhibits poor permeability (Fujimoto et al., 1987). The free carboxylic acid moiety in cefpodoxime offers opportunities for the preparation of prodrugs. Esterification of this carboxylic acid functional group with an isopropyloxycarbonyloxyethyl group removes the ionizable group and improves lipohilicity, enabling the compound to be absorbed by passive diffusion after oral administration (Fujimoto et al., 1987). Approximately 50% of the drug is reported to be absorbed systemically as cefpodoxime (Tremblay et al., 1990).
KeywordsCefpodoxime Proxetil Ester Prodrug Poor Oral Bioavailability Gonococcal Urethritis Carboxylic Acid Functional Group
Unable to display preview. Download preview PDF.
- Hamaura T, Kusai A, and Nishimura K. Gel Formation of Cefpodoxime Proxetil. STP Pharm Sci 1995a; 324–331Google Scholar
- Hamaura T, Kusai A, and Nishimura K. Unusual Dissolution Behavior of Cefpodoxime Proxetil: Effects of pH and Ionic Factor. STP Pharm Sci 1995b; 332–338Google Scholar
- Nakao H, Fujimoto K, Ishihara S, Sugawara S, and Igarashi I. Cephalosporin Derivatives, Their Preparation and Composition Containing Them. Eur Pat Appl.(1982); EP 0 049 118 A3Google Scholar