The Drug development process - Pharmaceutical Biotechnology: Concepts and Aapplications - page 59

The Drug development process

4.1 Introduction

In this chapter, the life history of a successful drug will be outlined (summarized in Figure 4.1).
A number of different strategies are adopted by the pharmaceutical industry in their efforts to iden-
tify new drug products. These approaches range from random screening of a wide range of biological
materials to knowledge-based drug identifi cation. Once a potential new drug has been identifi ed, it is then
subjected to a range of tests (both in vitro and in animals) in order to characterize it in terms of its likely
safety and effectiveness in treating its target disease. The developer will also undertake manufacturing-
related development work (development and initial optimization of upstream and downstream process-
ing; Chapters 5 and 6), as well as investigating suitable potential routes of product administration.
After completing such preclinical trials, the developing company apply to the appropriate gov-
ernment-appointed agency, e.g. the Food and Drug Administration (FDA) in the USA, for ap-
proval to commence clinical trials (i.e. to test the drug in humans). Clinical trials are required to
prove that the drug is safe and effective when administered to human patients, and these trials may
take 5 years or more to complete. Once the drug has been characterized, and perhaps early clinical
work is underway, the drug is normally patented by the developing company in order to ensure that
it receives maximal commercial benefi t from the discovery.
Upon completion of clinical trials, the developing company collates all the preclinical and clini-
cal data they have generated, as well as additional pertinent information, e.g. details of the exact
production process used to make the drug. They submit this information as a dossier (a multi-
volume work) to the regulatory authorities. Regulatory scientifi c offi cers then access the informa-
tion provided and decide (largely on criteria of drug safety and effi cacy) whether the drug should
be approved for general medical use.
If marketing approval is granted, the company can sell the product from then on. As the drug
has been patented, they will have no competition for a number of years at least. However, in order
to sell the product, a manufacturing facility is required, and the company will also have to gain
manufacturing approval from the regulatory authorities. In order to gain a manufacturing licence,
regulatory inspectors will review the proposed manufacturing facility. The regulatory authority
will only grant the company a manufacturing licence if they are satisfi ed that every aspect of the
manufacturing process is conducive to producing a safe and effective product consistently.