The drug development process

The drug development process :
In this chapter. the life history of a successful drug will be outlined (summarized in Figure 2.1).
A number of different strategies are adopted by the pharmaceutical industry in their efforts to
identify new drug products. These approaches range from random screening of a wide range of
biological materials to knowledge-based drug identification. Once a potential new drug has been
identified. 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.

After completing such pre-clinical trials. the developing company apply to the appropriate
government-appointed agency (e. g. the FDA in the USA) for approval 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 under way.
the drug is normally patented by the developing company. in order to ensure that it receives
maximal commercial benefit from the discovery.

Upon completion of clinical trials. the developing company collates all the pre-clinical and
clinical data they have generated. as well as additional pertinent information. e.g. details of the
exact production proces used to make the drug. They submit this information as a dossier (a
multi-volume work) to the regulatory authorities. Regulatory scientific ofiicers then assess the
information provided and decide (largely on criteria of drug safety and efiicacy) whether the
drug should be approved for general medical use.
lfmarketing 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. a regulatory inspector will review the proposed manufacturing facility. The regulatory
authority will only grant the company a manufacturing licence if they are satisfied that every
aspect of the manufacturing process is conducive to consistently producing a safe and effective
product.
Regulatory involvement does not end even at this point. Post-marketing surveillance is
generally undertaken. with the company being obliged to report any subsequent drug-induced
side el’fects,«"adverse reactions. The regulatory authority will also inspect the manufacturing facility
from time to time in order to ensure that satisfactory manufacturing standards are maintained.