04.04 Clinical Trials - Introduction

At some stage in the drug development procedure, a drug patent has to be applied for, to protect your discovery from other companies. Patents are valid for 15-17 years. During the patent, all monies made by that drug are returned to the pharmaceutical company that invested in the development. However as preclinical testing takes on average 1.5 to 5 years, and clinical trialling take 5 to 7 years on average, there may not be much time for the developing company to recoup their investment. After a patent expires, the generic drug can be made by other companies, commonly known as generic companies. The generic companies make drugs but they do not pay towards the development of the drug. After the patent expires, the pharmaceutical company that discovered the drug, no longer receives all the money from that drug.

After successful preclinical testing, a few new drugs enter the next stage, which is clinical trialling. Clinical trials are experiments in humans to evaluate drugs, medical devices, biologics etc. Thus, clinical trials are to evaluate interventions in general. The results of clinical trials are presented to the authorities for assessment. This assessment is carried out be the Federal Drug Administration (FDA) in US, or the Therapeutic Goods Administration (TGA) in Australia. If the FDA or TGA accept that the drug does more good than harm, it is registered for clinical use. The clinical development of drugs does not stop at registration, as there is ongoing preclinical and clinical assessment. It is presently considered that it costs A$1.2 billion for a single, successful new drug.

Only about 10% of compounds that enter clinical trial are approved/registered for sale. Clinical trials are under stringent law enforced guidelines. These guidelines include ethics, which is assessed by human ethics committee, and patient consent. For patient consent, they must be fully informed in lay language of exactly what is happening in the trial. Clinical trials of drugs are often funded by pharmaceutical company with independent investigators. Without this funding, there would be little development of new drugs. There is some government funding available for clinical trials of complementary and alternative medicines in the US, which allows these medicines to be properly evaluated. Clinical trials are not quick, as they take 7-9 years.