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Colorectal Cancer Health Center

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Clinical Trials for Colorectal Cancer

What are the Different Phases of a Clinical Trial?

In a Phase I clinical trial, researchers give the new treatment for colorectal cancer to a small number of patients to determine the best way to give it and how much can be given safely.

In a Phase II clinical trial, researchers further determine the effect of a treatment on colorectal and other specified cancers and its safety in a larger number of people.

In a Phase III clinical trial, researchers compare the new treatment with the standard treatment in a large number of people.

In a Phase IV clinical trial, researchers apply the new treatment to general patient care. For example, a new drug that was found effective in a clinical trial may be used together with other effective drugs to treat the particular disease or condition in a select group of patients. Information is also gathered as to the long term effects of the drug.

What Are the Advantages of Participating in a Clinical Trial?

  • You may receive a new treatment before it is widely available to the public.
  • You can provide researchers with the information they need to continue developing new procedures and introducing new treatment methods.
  • Your treatment costs may be decreased, because the company or agency sponsoring the study may pay for many of the tests and doctor visits directly related to the trial. Be sure to discuss your treatment costs with the doctors and nurses conducting the trial.

Could Problems Arise From Participating in a Clinical Trial?

This will depend on the type of treatment and the participant's condition.

Because the drug or device being studied is new, all of the risks and side effects of the treatment are not known at the beginning of the clinical trial. There may be unknown side effects, as well as expected and unexpected benefits. It is important to note that most treatments, as well as the disease or condition itself, have potential unpleasant effects.

Participants will be informed of any known side effects they could experience, as well as any side effects that occur or become known while they are participating in the trial.

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