Template:Drug Testing table

From Embryology
Drug Testing 
Typical testing of new drug compound today involves a lengthy series of animal and human studies.

Animal studies

Usually tested in at least two mammalian species (rats and guinea pigs) using both single and repeated doses. For determining reproductive effects, tests on both male and female animals with dosing begins 4 weeks prior to mating are conducted to determine effects on fertility in both sexes, on embryogenesis, and on fetal malformation.

Human Clinical trials

Following animal studies to determine dose, efficacy and apparent safety, human studies can commence. Clinical trials are carried out under very strict conditions, set by international regulatory bodies in agreement with the principles espoused in the Declaration of Helsinki. There are four phases to the trials.

  • Phase I trials - conducted in small groups of 10 to 20 healthy young male volunteers. Designed to examine how the drug is absorbed, distributed, metabolised and excreted by the body and to establish the safe dose for phase II trials.
  • Phase II trials - conducted in 50 to 100 patients with the disease rather than healthy volunteers as in phase I. Designed to examine what effect the drug has on the body (heart rate, blood pressure and cognitive effects) depending on the disease the drug is being developed to treat.
  • Phase III trials - conducted in 100’s of patients (larger numbers) with a particular disease or condition and are generally randomised comparative double-blinded studies. Using a comparator of either placebo, another active drug already used, or both. Several phase III trials are usually required by the regulatory authorities. Note that even these studies may not identify uncommon adverse effects, until used widely in the community.
  • Phase IV trials - (post-registration) conducted in 1000’s of patients over several years, these trials are randomised controlled trials undertaken after the drug has been registered.
After phase I to III the pharmaceutical company compiles all study data for independent assessment by government regulatory authorities in each country.

Regulatory Authorities: FDA in the USA, Therapeutic Goods Administration (TGA) in Australia, Medsafe in New Zealand, Medicines & Healthcare products Regulatory Agency (MHRA) in the UK, and Health Products and Food Branch (HPFB) in Canada.

Declaration of Helsinki
The Declaration of Helsinki was developed by The World Medical Association (WMA) as a statement of ethical principles for medical research involving human subjects, including research on identifiable human material and data. The Declaration is intended to be read as a whole and each of its constituent paragraphs should not be applied without consideration of all other relevant paragraphs. It is widely regarded as the cornerstone document on human research ethics. It is named after the location of its initial adoption in Helsinki, Finland, in June 1964.