About Clinical Trials

A clinical trial is a study designed and performed with human volunteers to evaluate a new therapy. Results from clinical trials help provide an understanding how new therapies work, how effective they are, and if they are safe enough for use by the public. 

In the U.S., if the results of a clinical trial indicate that the therapy is safe and effective, they are submitted to United States Food and Drug Administration (FDA) for review. The FDA uses this information in clearing the device for use with patients.

Clinical trial phases

Clinical trials are performed in phases. These phases are briefly summarized below:

• Phase I studies test a new treatment in a small group of people for the first time to determine its safety and side effects.
• Phase II studies test the treatment on a larger group of people and further evaluate its safety and determine how well it works.
• Phase III studies test the treatment on large groups of people to determine its safety and effectiveness, and monitor side effects. Phase III studies also compare the new treatment to commonly used treatments and collect information about how to use the new treatment safely.
• Phase IV trials are known as “post-marketing studies.” Their purpose is to further delineate the treatment’s risks and benefits and determine it’s optimal use. 

Should you participate in a clinical trial?

Taking part in a clinical trial is one way to make a contribution to the advancement of medicine. Information gathered during a clinical trial can lead to safer and more effective treatments. However, there are risks. The decision to participate should be made only with a full understanding of those involved. Consult with your doctor before deciding.

Where to learn more

More information about clinical trials can be found at www.clinicaltrials.gov/ct2/home. If you are considering participating in a clinical trial, visit  “Understanding Clinical Trials”