What are clinical trials, and why are they important?
Clinical trials are research studies that involve people. These studies test new ways to prevent, detect, diagnose, or treat diseases. People who take part in cancer clinical trials have an opportunity to contribute to scientistsí knowledge about cancer and to help in the development of improved cancer treatments. They also receive state-of-the-art care from cancer experts.
Are there different types of cancer clinical trials?
Yes. Cancer clinical trials differ according to their primary purpose. They include the following types:
Treatment. These trials test the effectiveness of new treatments or new ways of using current treatments in people who have cancer. The treatments tested may include new drugs or new combinations of currently used drugs, new surgery or radiation therapy techniques, and vaccines or other treatments that stimulate a personís immune system to fight cancer. Combinations of different treatment types may also be tested in these trials.
Prevention. These trials test new interventions that may lower the risk of developing certain types of cancer. Most cancer prevention trials involve healthy people who have not had cancer; however, they often only include people who have a higher than average risk of developing a specific type of cancer. Some cancer prevention trials involve people who have had cancer in the past; these trials test interventions that may help prevent the return (recurrence) of the original cancer or reduce the chance of developing a new type of cancer
Screening. These trials test new ways of finding cancer early. When cancer is found early, it may be easier to treat and there may be a better chance of long-term survival. Cancer screening trials usually involve people who do not have any signs or symptoms of cancer. However, participation in these trials is often limited to people who have a higher than average risk of developing a certain type of cancer because they have a family history of that type of cancer or they have a history of exposure to cancer-causing substances (e.g., cigarette smoke).
Diagnostic. These trials study new tests or procedures that may help identify, or diagnose, cancer more accurately. Diagnostic trials usually involve people who have some signs or symptoms of cancer.
Quality of life or supportive care. These trials focus on the comfort and quality of life of cancer patients and cancer survivors. New ways to decrease the number or severity of side effects of cancer or its treatment are often studied in these trials. How a specific type of cancer or its treatment affects a personís everyday life may also be studied.
Who sponsors clinical trials?
Government agencies, such as NCI and other parts of the National Institutes of Health (NIH), the Department of Defense, and the Department of Veterans Affairs, sponsor and conduct clinical trials. In addition, organizations or individuals, including physicians, academic medical centers, foundations, volunteer groups, and biotechnology and pharmaceutical companies, also sponsor cancer clinical trials.
NCI sponsors a large number of clinical trials each year, and it has developed a variety of programs to make cancer clinical trials widely available in the United States and elsewhere. These programs include the following:
The Clinical Trials Cooperative Group Program, which brings researchers, cancer centers, and doctors together into cooperative research groups. These groups work with NCI to identify important questions in cancer research and to design and conduct clinical trials that involve patients at multiple locations to answer those questions. Cooperative groups are located throughout the United States and in Canada and Europe. For more information, refer to the fact sheet NCIís Clinical Trials Cooperative Group Program.
The Cancer Centers Program, which provides support to research-oriented institutions that have been recognized as NCI-designated Cancer Centers or Comprehensive Cancer Centers because of their scientific excellence. More information is available from the NCI-Designated Cancer Centers Database.
The Community Clinical Oncology Program (CCOP), which makes clinical trials available in a large number of communities across the United States. Through the CCOP, local hospitals throughout the country affiliate with an NCI-designated Cancer Center or Clinical Trials Cooperative Group, which makes it easier for doctors at those hospitals to offer their patients participation in an NCI-sponsored clinical trial. Consequently, patients do not have to travel long distances or leave loved ones to take part in an NCI-sponsored trial. The Minority-Based Community Clinical Oncology Program (MBCCOP) focuses on encouraging minority populations to take part in cancer clinical trials. It is important for members of these populations to participate in cancer clinical trials to determine which cancer treatments are most effective for people with different ethnic and racial backgrounds.
The NCI Community Cancer Centers Program (NCCCP), which is a program testing the concept of a national network to expand cancer research and deliver the latest, most advanced cancer care to more Americans in their home communities. One of the goals of the NCCCP is to increase patient participation in clinical trials in community settings.
The Specialized Programs of Research Excellence (SPOREs), which bring together scientists and researchers to design and implement research programs, including clinical trials, to improve the prevention, detection, diagnosis, and treatment of specific types of cancer.
The National Institutes of Health Clinical Center, which is a research hospital located in Bethesda, Maryland. Trials at the Clinical Center are conducted by the components of NIH, including NCI. The NCI fact sheet Cancer Clinical Trials at the NIH Clinical Center has more information.
Where do cancer clinical trials take place?
Cancer clinical trials take place in cities and towns across the United States and in other countries. They take place in doctorsí offices, cancer centers and other medical centers, community hospitals and clinics, and veteransí and military hospitals. A single trial may take place at one or two specialized medical centers only or at hundreds of offices, hospitals, and centers.
Who manages clinical trials?
Each clinical trial is managed by a research team that can include doctors, nurses, research assistants, data analysts, and other specialists. The research team works closely with other health professionals, including other doctors and nurses, laboratory technicians, pharmacists, dietitians, and social workers, to provide medical and supportive care to people who take part in a clinical trial.
The research team closely monitors the health of people taking part in the clinical trial and gives them specific instructions when necessary. To ensure the reliability of the trialís results, it is important for the participants to follow the research teamís instructions. The instructions may include keeping logs or answering questionnaires. The research team may also seek to contact the participants regularly after the trial ends to get updates on their health.
What are eligibility criteria, and why are they important?
Every clinical trial has a protocol, or action plan, that describes what will be done in the trial, how the trial will be conducted, and why each part of the trial is necessary. The protocol also includes guidelines for who can and cannot participate in the trial. These guidelines, called eligibility criteria, describe the characteristics that all interested people must have before they can take part in the trial. Eligibility criteria can include age, sex, medical history, and current health status. Eligibility criteria for cancer treatment trials often include the type and stage of cancer, as well as the type(s) of cancer treatment already received.
Enrolling people who have similar characteristics helps ensure that the outcome of a trial is due to the intervention being tested and not to other factors. In this way, eligibility criteria help researchers obtain the most accurate and meaningful results possible.