About Clinical Trials

What Is A Clinical Trial

Clinical trials are medical research studies performed on people to determine whether new medical approaches, treatments, therapies, or devices are safe and effective. Doctors use clinical trials to learn how diseases start and progress, find new ways to improve health care, develop new therapies and preventive measures, and monitor treatment changes over time. Clinical trials are the stepping-stones to market a drug or other therapy.

What are the four phases of clinical trials?

Clinical trials advance through four phases to test a treatment, find the appropriate dosage, and look for side effects.

Phase 1 - Designed to test safety and tolerability, Phase 1 typically involves a small number of healthy volunteers.

Phase 2 - More participants are involved in Phase 2 to measure the drug’s effectiveness. Additional dosing information may be obtained.

Phase 3 - Studies conducted during Phase 3 of a clinical trial will involve large groups of patients or very large groups of participants with a specific disease the trial drug intends to impact. Researchers also compare results among those taking the experimental drug with results from those who are taking a placebo. Drug intervention testing may also be used in combination with other medications or treatments during Phase 3. If, after all these tests prove safe and effective, the FDA approves it for clinical use.

Phase 4 - During Phase 4 clinical trials, researchers test the drug or medical device's effectiveness, safety, and side effects after it has been approved by the FDA. In Phase 4 studies, doctors monitor how people use the drug long-term.

Preclinical

Several Years

Phase 1

Months

Phase 2

Months to Years

Phase 3

Years to Decades

Phase 4

Ongoing