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Frequently Asked Questions

What is a clinical trial?
A clinical trial is one of the final stages of a long and careful cancer research process. Studies are done with cancer patients to find out whether promising approaches to cancer prevention, diagnosis, and treatment are safe and effective.
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What are the different types of clinical trials?

  • Treatment trials test new treatments (like a new cancer drug, new approaches to surgery or radiation therapy, new combinations of treatments, or new methods such as gene therapy).
  • Prevention trials test new approaches, such as medicines, vitamins, minerals, or other supplements that doctors believe may lower the risk of a certain type of cancer. These trials look for the best way to prevent cancer in people who have never had cancer or to prevent cancer from coming back or a new cancer occuring in people who have already had cancer.
  • Screening trials test the best way to find cancer, especially in its early stages.
  • Quality of Life trials (also called Supportive Care trials) explore ways to improve comfort and quality of life for cancer patients.

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What are the phases of clinical trials?
Most clinical research that involves the testing of a new drug progresses in an orderly series of steps, called phases. This allows researchers to ask and answer questions in a way that results in reliable information about the drug and protects the patients. Clinical trials are usually classified into one of three phases:

  • Phase I trials: These first studies in people evaluate how a new drug should be given (by mouth, injected into the blood, or injected into the muscle), how often, and what dose is safe. A phase I trial usually enrolls only a small number of patients, sometimes as few as a dozen.
  • Phase II trials: A phase II trial continues to test the safety of the drug, and begins to evaluate how well the new drug works. Phase II studies usually focus on a particular type of cancer.
  • Phase III trials: These studies test a new drug, a new combination of drugs, or a new surgical procedure in comparison to the current standard. A participant will usually be assigned to the standard group or the new group at random (called randomization). Phase III trials often enroll large numbers of people and may be conducted at many doctors' offices, clinics, and cancer centers nationwide.

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Who is eligible to participate in a clinical trial?
Each study has its own guidelines for who can participate, called eligibility criteria. To ensure the strongest results, researchers want study participants to be alike in key ways. Examples of eligibility criteria for a treatment trial might be a particular type and stage of cancer, age, gender, or previous treatments. The eligibility criteria are included in the study plan. To find out if you are eligible for a particular study, talk to your doctor or the doctor or nurse in charge of enrolling patients for the study.
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What are the potential risks and benefits of participating in a clinical trial?
Potential benefits include: Health care provided by leading physicians in the field of cancer research. Access to new drugs and interventions before they are widely available. Close monitoring of your health care and any side effects. A more active role in your own health care. If the approach being studied is found to be helpful, you may be among the first to benefit. An opportunity to make a valuable contribution to cancer research.

The potential risks include: New drugs and procedures may have side effects or risks unknown to the doctors. New drugs and procedures may be ineffective, or less effective, than current approaches. Even if a new approach has benefits, it may not work for you.
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What is informed consent?
Informed consent is a process in which you learn the key facts about a clinical trial before you decide whether or not to participate. In addition to talking about these facts with the research doctor or nurse, they will be included in a written consent form that you can take home to read and discuss. The consent form will include details about: the study approach the intervention given in the trial the possible risks and benefits the tests you may have Don't hesitate to ask questions until you have all the information you need. While informed consent begins before you agree to participate in a trial, you should feel free to ask the health-care team any questions you have at any point. Informed consent continues as long as you are in the study. You can change your mind and leave the study whenever you want -- before the study starts or at any time during the study or follow-up period.
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What happens during a trial?
If you decide to participate in a clinical trial, you will work with a research team. Team members may include doctors, nurses, clinical research associates, social workers, dieticians, and other health care professionals. They will provide your care, monitor your health carefully, and give you specific instructions about the study. Participating in a trial may mean that you might have more tests and doctor visits than you would if you weren't in the study. Team members also may continue to stay in contact with you after the trial ends. To make the trial results as reliable as possible, it is important for participants to follow the research team's instructions. That means having all doctor visits and tests, taking medicines on time, and completing logs or answering questionnaires.
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Could I receive a placebo if I participate in a clinical trial?
In treatment trials involving people who have cancer, placebos ("dummy" pills that contain no active ingredient) 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. When no standard treatment exists for a cancer, a study may compare a new treatment with a placebo. However, you will be told about this possibility during informed consent, before you decide whether or not to take part in the study.
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