European Journal of Biomedical and Pharmaceutical Sciences

AN UPDATED CLASSIFICATION OF PRODRUGS

Rakesh K. Goyal* and Divyadeep Goyal

ABSTRACT

Clinical utility of many potential therapeutic agents is hampered by their undesirable organoleptic, physicochemical and biological properties. The pharmaceutical world improves therapeutic efficacy by minimizing the number and magnitude of undesirable properties while retaining the desirable ones. Since the late nineteenth century, prodrugs, bioreversible derivatives of drug molecules, have been widely used to optimize the clinical application of potential drug candidates. Prodrugs improve pharmaceutical, pharmacokinetic/pharmacodynamic properties of drug molecules via transient chemical modifications in order to develop new entities with superior efficacy. Basically prodrugs are designed to optimize ―drug like‖ properties such as permeation across membranes, metabolic and excretory properties, low lipid or water solubility, low target selectivity, chemical instability, presystemic metabolism, toxicity, and masking of offensive taste/odor, irritation/pain at the site of injection. Conventional method of prodrug design involving non-specific chemical approach classifies prodrugs into two broad categories i.e. carrier-linked prodrugs and bioprecursors depending upon the type of derivatization and the carrier used. In this article, authors discuss basic concepts and propose an updated classification of prodrugs by citing suitable examples.

Keywords: Prodrug; Bioreversible derivatives; Prodrug activation; Design of Prodrugs; Drug targeting.