A study subject who has the disease or condition for which the investigational product is being studied.
Pharmacokinetics
Relationship between mechanisms of drug absorption, distribution and elimination over time.
Phase (of Drug Development):
Drug development is divided into phases that are determined by the main objectives of the drug development process.
Phase I
Phase I studies are the first studies conducted in humans, usually in healthy volunteers, as the intention is to collect data on the tolerability, pharmacokinetics and biological effects of the drugs, not to treat disease or illness. Phase I studies with cytotoxic drugs, for e.g. certain anti-cancer drugs, tend to be carried out in patients who have the disease.
Phase II
Phase II studies involve administration of drug to a small number of patients with the primary objectives of demonstrating the effectiveness of the treatment and assessing short term tolerability profile in the target population.
Phase III
Phase III studies are conducted in a large number of patients and are designed to compare the efficacy of the new treatment against existing therapies while providing an accurate estimate of the occurrence of adverse events in a clinical environment.
Phase IV
Phase IV studies are additional studies performed after a regulatory approval of the drug and are sometimes referred to as "post-marketing" studies. The purpose of these studies is to gain broader understanding of the safety of the drug in the intended population or to secure approval for use in new indications
Placebo
An inactive or dummy treatment administered to the control group in order that the specific and non-specific effects of the experimental treatment can be distinguished. The placebo may be used in screening or washout periods or used as a comparator to determine the efficacy of a medication.
Preclinical Phase
Laboratory or animal studies conducted prior to administration to man.
Protocol
A document that describes the objectives, design, methodology, statistical considerations and organisation of the study. The protocol must be complete and approved before a study can enrol subjects
