Clinical trials are research studies that involve people. Each study tries to answer scientific questions and to find better ways to prevent, diagnose or treat cancer. See What Is a Clinical Trial? ³ as well as Taking Part in Cancer Treatment Research Studies ⁴.

In cancer research a clinical trial is designed to show how a particular anticancer strategy -- for instance, a promising drug, a gene therapy treatment, a new diagnostic test, or a possible way to prevent cancer -- affects the people who receive it.

A clinical trial is one of the stages of a long and careful cancer research process. Getting promising results from testing a new drug on mice, for example, is a preliminary step to human research studies. Treatments that work well in mice do not always work well in people. See How Is a Clinical Trial Planned and Carried Out? ⁵

People can benefit from clinical trials. In treatment trials, for example, participants receive high-quality cancer care -- and will be among the first to benefit if a new approach is proven to work. See Should I Take Part in a Clinical Trial? ⁶

Who's eligible to participate in a clinical trial? Each study has its own guidelines for who can participate. Generally, participants are alike in key ways - such as the type and stage of cancer, age, gender, and other factors. See How Do I Take Part in a Clinical Trial? ⁷

Are there drawbacks? New treatments under study are not always better than, or even as good as, standard care. And they may have unexpected side effects. Through a process called informed consent you will learn about a study's treatments and tests, and their possible benefits and risks, before deciding whether or not to participate. See A Guide to Understanding Informed Consent. ⁸

Do some people receive a placebo in clinical trials? In treatment trials, involving people who have cancer, placebos are very rarely used.

Many treatment trials are designed to compare a new treatment with a standard treatment, which is the best treatment currently known for a cancer, based on results of past research. In these studies patients are randomly assigned to one group or another.

Where do clinical trials take place? They are underway all over the country - in cancer centers, other major medical centers, community hospitals and clinics, physicians' offices and veterans' and military hospitals in numerous cities and towns around the United States.

Who pays for the patient care costs on clinical trials? Health plans and managed care providers do not always cover all patient care costs in a study. What they cover varies by plan and by study. Ask a doctor, nurse or social worker from the study to help you determine in advance what costs are covered. The research costs, such as data management, are covered by the study sponsor. See Clinical Trials and Insurance Coverage: A Resource Guide ⁹.