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What Is A Clinical Trial?

Clinical trials are studies designed to test new therapies on humans. All different types of treatment are studied by this method (e.g. radiation therapy, chemotherapy, biological agents, medical devices and more).

Research initially starts in a laboratory and on animals. If these studies can show benefits with minimal risk they are tested in humans to determine effectiveness and safety. The studies done in humans are conducted in 3 phases:

Phase I trials are used to determine the appropriate dose and schedule of the treatment. Additionally, the researchers begin to determine the side effects associated with the therapy.

Phase II trials are used to test the treatment on subjects to determine the effectiveness of the treatment.

Phase III trials are used to test the treatment on a group of individuals with a particular type of cancer. The new therapy will be compared to the current standard treatment for that type of cancer. Thus, ½ the subjects will get the new therapy and ½ will receive the standard treatment. Subjects who are enrolled in Phase III will be randomized (like the flip of a coin) to one of the 2 groups. The subject cannot select which of the 2 treatments they want.

Individuals with cancer often have questions about whether or not they should agree to be in a study. Sometimes the study may not have a direct benefit for you, but may benefit thousands of other people who also have your disease. It is important for you to thoroughly understand the study. If you do not understand then you should talk to your doctors and nurses and let them know you do not understand. It may also be helpful to carry a little spiral notebook and you can write all the answers to your questions in the notebook.
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