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Clinical Trials: Interpretting the Data
 The term cancer includes at least 100 different types of diseases that can develop in any part of the body. All of these diseases known as cancer have one thing in common — abnormal, unregulated growth of cells that can ultimately spread to vital organs, such as the liver, lung or brain.
Today’s “standard” cancer treatments are mainly the results of patients participating in past cancer clinical trials. Tomorrow’s “standard” care will exist due to the results of today’s clinical trials. Clinical trials are research studies for which cancer patients volunteer to participate because they understand that they are getting the best treatments available and also contributing to the scientific evidence that helps future patients. Many of these trials involve investigational treatments that are not yet approved by the U.S. Food and Drug Administration (FDA) for widespread use.
The trials are conducted under the supervision of physicians and other research professionals and sponsored by government agencies, such as the National Cancer Institute, by individual doctors and health-care organizations or by the pharmaceutical or biotechnology companies that developed the treatments.
Each clinical trial has specific guidelines about eligibility to participate in the studies. The inclusion/exclusion criteria for cancer clinical trials may specify a certain age range, gender and a specific type or stage of cancer. Other factors include the volunteer’s medical condition and previous treatment history.
The U.S. government sets strict guidelines and provides safeguards to protect those who participate in clinical trials. In addition, clinical trials in the United States must be monitored at the local medical centers by an institutional review board (IRB), which is a committee of physicians, community advocates, statisticians and others established to protect the rights of the participants and to make sure the trials are safe and ethical, and that the consent form clearly describes the procedures, potential benefits, risks, unknowns and alternatives of a trial.
"I would encourage each of you to consider participating in clinical trials that might be available for your stage of cancer. Your participation may be as simple as allowing the information about your cancer care or your pathology specimens to be used appropriately for research purposes. It might also involve being part of a clinical trial that is designed to improve cancer treatments with new or investigational treatments — or new combinations of treatments — that would benefit you and future generations of cancer patients." - Dr. Balch
What happens in a clinical trial depends on the type of trial being conducted. In comparative studies, volunteers are usually assigned at random to one of two or more groups. In one group, the participants receive the drug or treatment being studied, and in the other, the volunteers receive a treatment that is already available (standard treatment) or a placebo (a pill with inactive ingredients or a device that doesn’t work). In most studies, the volunteer is informed of the treatment they will receive; however, sometimes, the participants do not know whether they are receiving the new treatment or the placebo or standard treatment. Every clinical trial follows a set of rules called a protocol. In addition to the inclusion/exclusion criteria, the protocol specifies the tests to be done, procedures to use, medications and their doses involved in the study and the duration of the study. Participants work with a research team that may include doctors, nurses, social workers and other health-care professionals.
The research team gives specific instructions for participating in the trial, evaluates each patient’s health at the beginning of the trial, monitors the patient’s health carefully during the trial and stays in touch with every patient participant after the study ends. Participants get the most benefit from the study if they carefully follow the protocol and remain in contact with the research staff.
Clinical trials may be conducted in a hospital, university, doctor’s office or community clinic. Some clinical trials offer payment to participants, but most do not. Participants may also be reimbursed for expenses associated with participating in the study, such as transportation, childcare, meals and accommodations.
Whether you want to participate in a clinical trial or wish to find out the results of a specific clinical trial, you need to understand how to interpret the language of them. These are some standard terms used in clinical trials:
Investigational drug or therapy. The drug or therapy being studied is considered investigational while it is being studied and before the FDA has judged it to be safe and effective and has approved it to be marketed in the United States for a specific use. The FDA may approve a drug or therapy for use in treating a certain type of cancer but consider it investigational for other uses.
Randomized. Many clinical trials are randomized. That means the clinical trial is a research study involving human participants who are assigned at random to two or more separate groups so that the results of different treatments can be compared. Volunteers for the trial get either standard therapy or the therapy being investigated.
Standard therapy. Standard therapy is the drug or other type of treatment that experts agree is the most accepted, widely used and appropriate therapy for a particular type and stage of cancer. Researchers are trying to determine if the new therapy under study is as good as, better than or worse than the standard therapy. Sometimes the standard therapy might be considered to be supportive care.
Placebo controlled. Clinical trials may not only be randomized but also placebo controlled, which means that participants may be randomized to receive the new drug or therapy being studied or to receive a placebo. People who receive a placebo are said to be in the control group, while those who receive the investigational therapy are said to be in the treatment arm of the study. Depending on the design of the trial, the placebo may be given alone or added on to standard therapy.
Blinded studies. Clinical trials may be blinded, that is, the researchers or the participants or both may not know which treatment is being administered to the patients in the study. A single-blind trial is one in which the participants do not know which treatment they are receiving, but the researchers do. A double-blind trial is one in which neither the researchers nor the participants know who is receiving the investigational drug or therapy and who is not.
Relative risk. This is a statistical term meaning the likelihood that cancer will occur within a specific time in one group versus another.
Statistical significance. If the results of a clinical trial are said to be statistically significant, it means the results are not likely to have occurred by chance. A statistically significant difference in the results of the study means that statistical evidence shows there is a difference, but the difference may not necessarily be large.
p-value. This is a statistical measure to determine whether it is more likely than not that the results of a clinical trial are statistically significant. Results are usually considered statistically significant when the p-value is 0.05 or smaller. A p-value of 0.01 or even 0.001 signifies an even more significant result.
Trial size. The trial size, or the number of participants in a clinical trial, greatly influences the trial’s statistical significance. With too few participants, the trial results may not be significant enough for the researchers to draw a valid conclusion. Before starting a clinical trial, researchers must determine how many people must be enrolled in the trial to get a statistically significant result.
Before you decide to participate in a clinical trial, you should talk with the members of your medical team to learn the key facts about the trial, such as how long the trial will last, what treatments will be used and how, what the main purpose of the trial is, what risks and possible benefits are involved, who sponsors the trial, what personal costs or reimbursements may be involved, what happens if you are harmed by the investigational treatment, and whether you can remain on the treatment after the study ends.
If you decide to participate, the research team will explain the details of the study to you. They will also give you an informed consent document to sign to acknowledge that you understand what is involved in the study. You can take the document home and discuss whether you want to participate in the trial with family and friends and your doctor before you sign it. The informed consent document is not a contract, and you may withdraw from the trial at any time and still receive standard treatment for your cancer.
What are the risks? The side effects of the investigational treatment may be unpleasant, intolerable or even life threatening. Side effects are the unwanted physical effects of the treatment, such as headache, nausea or other physical problems. Your research team will be evaluating the side effects throughout the trial and afterward. Another risk is that the investigational treatment may not be effective for you. And the protocol may require more of your time and effort than standard treatments, including a hospital stay and more trips to the study site for additional treatments or evaluations.
To find a clinical trial right for you, first ask the members of your medical team if they can recommend a clinical trial that might benefit you. In addition, a number of government and private organizations provide listings of clinical trials and information about the trials on their Web sites, for a list of some of them, see “Additional Sources of Information” on this page.
Patients who volunteer to participate in these studies gain access to new, innovative treatments before they are available to the general public, and they can take an active role in their own health care and help others by participating in medical research. They can derive great value in their own health care and know they are contributing to the future care of others, including their own family members.
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