Clinical Trial

What is a Clinical Trial?

If early work suggests that a new treatment might be better than the standard treatment, doctors will carry out studies to compare the new treatment with the best available standard ones. This is called a controlled clinical trial and is the only reliable way of testing a new treatment. Often several hospitals around the country take part in these trials.

In a randomized controlled clinical trial, some patients will receive the best standard treatment while others will receive the new treatment, which may or may not prove to be better than the standard treatment. So that the treatments can be compared accurately, the type of treatment a patient receives is decided at random - typically, by a computer - and not by the doctor treating the patient. This is because it has been shown that if a doctor chooses the treatment, or offers a choice to the patient, he or she may unintentionally bias the result of the trial. A treatment is better either because it is more effective against the disease or because it is just as effective and has fewer unpleasant side effects.

Before any trial is allowed to take place an ethics committee must have approved it. Your doctor must have your informed consent before entering you into a trial. This means that you know what the trial is about, you understand why it is being conducted and why you have been invited to take part, and you appreciate exactly how you will be involved. Even after agreeing to take part in a trial, you can still withdraw at any stage if you change your mind. Your decision will in no way affect your doctor's attitude towards you. If you choose not to take part or you withdraw from a trial, you will then receive the best standard treatment rather than the new one with which it is being compared. If you do choose to take part in a trial, it is important to remember that whatever treatment you receive will already have been carefully researched.

Clinical trials are conducted in four phases. Progressing to the next phase requires that researchers carefully study the results of the previous phase. Following is an overview of each phase of a clinical trial:

• Phase I clinical trials are the first step in testing a new treatment in humans. Phase I clinical trials are designed to study how the human body reacts to the treatment and what side effects might occur at different dosages. Because Phase I trials may carry significant patient risk, only a small group of patients participate, and then only those who likely would not benefit from other treatments.
• Phase II clinical trials help researchers determine the safety and effectiveness of a treatment in patients with specific types of cancer. In other words, researchers are looking to answer this question: Does the new treatment have an anticancer effect?
• Phase III involves large numbers of participants and helps researchers decide if a new treatment is as good as, better than, or inferior to the best available standard treatment. Phase III clinical trials compare the results of people taking a new treatment with the results of people taking the best available standard treatment.
• Phase IV trials involve thousands of people in the study of potential side effects that were not apparent in Phase III. Phase IV clinical trials are conducted after a treatment has been approved by the Food and Drug Administration (FDA) and is being marketed.

Having a physician suggest a clinical trial does not necessarily mean that it's a last-resort treatment option for the patient. It simply means that the physician thinks society or the patient may potentially benefit from the treatment being studied.

What Trials are open at CRC Sites?

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