Oral controlled and sustained drug delivery systems: Concepts, advances, preclinical, and clinical status

Abstract Owing to the difficulty in developing new drug moieties, greater emphasis is being given to developing new drug delivery systems for existing drugs. The oral route is the major expedient route for drug administration. The maintenance of plasma concentration of drug within the therapeutic index is crucial for effective treatment. Oral controlled release products provide several lucrative advantages over conventional dosage forms by maximizing the pharmacokinetic and pharmacodynamic traits of drugs. Controlled and sustained release dosage forms provide temporal and spatial control over drug release which cannot be achieved by conventional or immediate release dosage forms. Therefore, in this chapter, attention has been paid on basics of controlled and sustained release dosage forms, as well as techniques and technology used in development of modified drug delivery systems. In addition, recently preclincally and clinically analyzed oral modified drug delivery systems have also been summarized.