About Clinical Trials

Clinical trials are research studies that try to answer scientific questions in a structured way and find better ways to treat or prevent diseases. A clinical trial is conducted to determine whether a new drug or treatment is both safe and effective when taken for a specific disease or condition. Clinical trials rely on patients who volunteer to participate and to try a new drug or treatment. In some cases, the drug has not yet been approved by the Food and Drug Administration for sale in the United States. Other times, the drug is available for sale, but is being tested for a new disease or condition.

There are four clinical trial stages.

• Phase 1 trials: Researchers test a new drug or treatment for the first time in a small group of people to evaluate its safety, determine a safe dosage range, and identify potential side effects.
• Phase 2 trials: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety profile.
• Phase 3 trials: The drug or treatment is given to even larger groups of people to confirm that it is effective, to determine side effects, to compare it other commonly used treatments, and to collect information that will allow the drug or treatment to be used safely.
• Phase 4 trials, or postmarketing studies: Additional information is collected to assess the risks and benefits of the new drug or treatment and to optimize its use.