WHAT ARE THE PHASES OF CLINICAL RESEARCH?
Phase I studies involve testing the investigational drug in a small number of healthy adult volunteers. The sole objective of these studies is safety. These studies are designed to determine how the drug is metabolized by the body and what pharmacologic actions the drug has. One objective of these studies is to determine the best way to administer the drugs (i.e., the preferred route). Phase II studies help determine how safe and effective a drug is, common short-term side effects of the drug, pharmacokinetic effects of the drug (i.e., the amount of drug that gets into the bloodstream, how quickly it gets there, and how long it stays there) and pharmacodynamic effects of the drug (i.e., the effects of the drug on the body). These studies involve a larger group of patients (e.g., 100 to 200 patients) and are usually conducted in patients who have the medical condition for which the drug is being studied. These studies are used to identify the dose range of the drug that will be tested i
