12 Answers to Common Questions About Clinical Trials

1. What Are Clinical Trials?

Clinical trials are research studies that test new interventions in people. An intervention can be a drug, a device such as a pacemaker, a diagnostic tool, a genetic test, or even a new way to prevent disease or offer support for sick people. In some cases, clinical trials test new uses for existing medications. Clinical trials also test new therapeutic options for existing drugs -- for example, a once-a-week dose instead of a daily dose or an inhaled medication instead of an injection. Researchers use clinical trials to find out whether an intervention is safe and whether it is effective. Keep two things in mind:

• Clinical trials are experiments -- researchers don't know whether the drug or device works or doesn't work beforehand
• They are not right for everyone

Clinical trials get started when researchers develop new ideas for medical research. These researchers may work for private companies (such as drug manufacturers), medical centers (including hospitals and medical schools), or government agencies. Before they begin any research on people, researchers must test their ideas in laboratory experiments and animal studies (sometimes called preclinical studies). Ideas that succeed in these early tests go on to clinical trials.

Clinical trials are required by federal law. The Food and Drug Administration (FDA) requires companies to show that new medical products are both safe and effective before approval. Clinical trials are the best way to prove that new medications, practices, or devices are safe and effective.

2. What Are Some Different Types of Clinical Trials?

Treatment trials are the most common type of clinical trials. They test new or alternative potential treatments for specific diseases or medical conditions.

Prevention trials test new ways to prevent specific diseases, evaluating new medications or lifestyle changes.

Screening trials test new ways to detect specific diseases, especially diseases that may have an early stage before they produce symptoms.

Diagnostic trials study tests or procedures that could be used to identify disease more accurately and at an earlier stage.

Genetics studies are sometimes part of another clinical trial. The genetics component of the trial may focus on how genetic makeup can affect detection, diagnosis, or response to treatment.

Other types of medical research studies involve people but do not involve new procedures. They range from experiments assessing the quality of new questionnaires to tests of organ functions.