Clinical trials are treatment studies conducted with volunteers that help doctors to evaluate new treatments. Each trial is designed to answer specific scientific questions and to find better ways to prevent or treat disease. Patients who participate in such studies may have opportunities to receive treatments that have shown promise in research. Patients who take part in clinical trials make important contributions to medical science. Although these patients take certain risks, they may be among the first to benefit from improved treatment methods.

Patients who are considering participation in a clinical trial are encouraged to ask for a copy of the full protocol--the document that describes the clinical trial in detail. Consent to participate in a trial should only be given after reviewing the full protocol and considering all other relevant clinical trials for which the patient might be eligible.

Most clinical research that involves the testing of new drugs progresses in an orderly series of steps. Cancer clinical trials generally follow three phases:

Phase I Trials - evaluate how a new drug should be administered (orally, intravenously, or by injection), how often, and in what dosage. A Phase I trial usually only enrolls a small number of patients.

Phase II Trails - provide preliminary information about how well the new drug works and generate more information about safety and benefit. Each Phase II study usually focuses on a particular type of cancer.

Phase III Trials - compare a promising new drug, combination of drugs, or procedure with the current standard. Phase III trials typically involve large numbers of people nation-wide. If you participate in a Phase III treatment trial, you are likely to be randomized (assigned by chance) to a group receiving either the new treatment or the standard treatment. The reason the clinical trial has been initiated is that the superiority of one treatment over the other has not yet been firmly established.

In the United States, one way to learn more about clinical trials is through PDQ, a computerized resource developed by the National Cancer Institute. PDQ contains information about cancer treatment and about clinical trials throughout the US. Cancer Information Service offices (1-800-4-CANCER) provide PDQ searches to callers and can tell physicians how to obtain regular access to the database. Information can also be found at http://cancertrials.nci.nih.gov. Another way to find out about clinical trials is to ask your hematologist how you can obtain information on trials in your area.