DRUG DELIVERY SYSTEMS AND PHARMACEUTICAL BIOTECHNOLOGY

About this lecture

This lecture is in two main parts, viz, Drug delivery systems and Pharmaceutical

biotechnology. The former will be considered first. However, as you will observe in the course of the lecture, there is significant overlap between the two topics.

 Introduction to Drug Delivery Systems

Ever since man began to treat various disease states with medicinal agents, the need to present medicines in the most suitable physical form for delivery to their sites of action has persisted. Some of the earliest drug delivery forms include solutions, suspensions and powders. Soon, cachets, pills, tablets and emulsions

In the early years and probably up to the middle of this century, formulation and production of drug delivery systems were far more of an art than science. The main objective then was to deliver the therapeutic agent in an administrable form. Little attention was paid to such desirable formulation objectives as masking unpleasant taste and odour, better aesthetics, controlled and/or prolonged drug

action, and enhanced patient acceptance. In the last four decades, however, particularly with the advent of the use of synthetic polymers in pharmaceutical formulation, there have been concerted and accelerated efforts to move towards perfection in drug delivery. Today, far more progress than was thought possible 60 years ago has been made in this field.

Several of the new drug delivery systems are still not available in the West African market due to their high cost. This situation is, however, expected to change in the years ahead. Therefore, there is a need to continually keep abreast of rapid developments in the highly dynamic area of drug delivery technology. This lecture is an effort in this direction.

In this lecture, no attempt will be made to discuss all the new drug delivery systems that have been invented nor will any of them be treated in great detail since a rapidly expanding field such as this cannot be adequately treated in a presentation of this nature. However, some of the more novel, exciting and promising advances that have been attained in drug delivery design will be highlighted. All the systems that will be examined have gone beyond the conceptual stage. They are either at the laboratory stage, undergoing clinical trials or already in the market.