Controlled release dosage forms: from ground to space.

Controlled release of drugs is one of the most significant advances in pharmacy. Due to the proposition of new routes for drug administration, today it is considered as a part of 'drug delivery'. Developments in biotechnology producing natural molecules, peptides and proteins have allowed high activity substances that require careful formulation for administration. Drug delivery is the discipline striving to sole the problem of optimisation of drug efficacy. In this contribution the last 25 years of drug delivery research have been examined pointing out the most significant break-through steps.