What Are Clinical Trials?

Clinical trials are research studies designed to find new and better ways to treat patients who have cancer and other diseases. Clinical trials are done to find out whether a newly developed treatment is safe and effective; how and in what dose the new treatment is best administered; and whether the treatment is better than other options.

Clinical trials may test new drugs, new approaches to using existing treatments, or newly developed methods of treatment, and are unique studies in that they rely on the participation of patients to test the new therapies. They are conducted only after a long process of research on the new treatment has already been completed.

When planning a clinical trial, an investigator (usually a physician) must write a detailed plan, or protocol, that outlines both the background and purposes of the study and the way in which the study will be conducted, ensuring that participants receive appropriate treatment and high-quality care, and that the research is conducted scientifically.

Clinical trials must go through three phases:

Phase I Trials

Phase I trials evaluate how a new drug should be given (for example, by mouth or injection), how often, and in what dose. Phase I trials begin after a treatment is approved to be tested on humans. Because of this, only a small number of participants are admitted into Phase I trials.

Phase II Trials

This kind of trial continue to test the safety of the drug and begin to evaluate how well the new drug works. Phase II studies usually focus on a particular type of cancer. Like Phase I trials, they often include a limited group.

Phase III Trials

This kind of trial tests a new drug or surgical procedure in comparison with the current standard for treatment. Participants are usually assigned at random either to the standard treatment group or to the new treatment group.