Prodrugs: bridging pharmacodynamic/pharmacokinetic gaps.

In this mini review, prodrugs are discussed with a focus on their pharmaceutical, pharmacokinetic, and pharmacodynamic objectives, as well as on the resulting therapeutic benefits. Carrier-linked prodrugs remain the most extensively investigated and receive due attention here with recent successes highlighted. A clear trend is apparent in modern prodrug research, namely the increased attention given to the knowledge-based design of bioprecursors, namely prodrugs devoid of a detachable promoiety. In most cases, such prodrugs are activated by in situ reduction, hence their designation as bioreductive prodrugs. This is a particularly active field in the design of more selective, small-molecule antitumor agents. New antimicrobial agents are also in the pipeline. In addition, biooxidative bioprecursors offer a promising strategy in specific cases, as illustrated by the successful antiaggregating agent clopidogrel.