A clinical trial is a research study in which volunteers receive investigational treatments under the supervision of a physician and other research professionals. These treatments are developed by pharmaceutical and biotechnology companies who select qualified physicians, also known as investigators, to conduct clinical trials to determine the benefits of investigational drugs.
Clinical trials are usually conducted in three phases (I, II, III). Only a small number of people participate in phase I trials while the later phases involve a larger number of volunteers.
Who can participate in a clinical trial?
All clinical trials have guidelines about who can participate. Before joining a clinical trial, a volunteer must qualify for the study. The factors that allow volunteers to participate in a clinical trial are called “inclusion criteria” and the factors that disallow volunteers from participating are called “exclusion criteria.” These criteria can include age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.
Some research studies seek participants with specific illnesses or conditions to be studied in a clinical trial, while others require healthy participants. It is important to note that inclusion and exclusion criteria are used to identify appropriate participants, promote participants’ safety, and ensure that researchers learn the information they need.
How does a clinical trial work?
In a clinical trial, a volunteer is usually assigned a specific study group. Volunteers in one study group may receive an investigational treatment or study drug while other volunteers may receive a placebo or a treatment already available.
A placebo is an inactive product used to assess the experimental treatment’s effectiveness. The participant, physician, and research staff may not know which volunteer receives a placebo and which receives the active treatment. Not knowing which participants are receiving the active treatment allows the physician and research staff to objectively observe the volunteers during the study. Regardless of which treatment volunteers receive, however, the level of medical attention and care that each receives is the same.