Clinical trials are research studies involving people. They are the final step in a long process that begins with preliminary laboratory research and animal testing. Clinical trials try to answer specific scientific questions to find better ways to prevent, detect, or treat diseases or to improve care for people with diseases.

Clinical trials are a critical part of the research process. Clinical trials translate basic scientific research results into better ways to prevent, diagnose, or treat cancer. Clinical trials are the final step in a long research process.

Clinical trials contribute to knowledge of and progress against cancer. Many of today's most effective cancer treatments are based on previous study results. Because of progress made through clinical trials, many people treated for cancer are now living longer.

The more people who participate in clinical trials, the faster critical research questions can be answered that will lead to better treatment and prevention options for all cancers. We will never know the true effectiveness of a cancer treatment or a way to prevent cancer unless more people are involved in clinical trials.

In the past, clinical trials were sometimes seen as the last resort for patients who had no other treatment choices. This is not true; there are many clinical trials for individuals whose cancer has not spread.

Enormous improvements in treating childhood cancer have come about as the direct result of clinical trials; more than 60 percent of U.S. children with cancer participate in clinical trials. In 2000, more than 70 percent of children with cancer were alive 5 years after diagnosis, compared to only 55 percent in the mid-1970s.

In contrast, fewer than 5 percent of U.S. adults with cancer participate in clinical trials-far fewer than the number needed to answer the most pressing cancer questions quickly.

According to a 2000 Harris Interactive survey, most people with cancer were either unaware or unsure that participation in clinical trials was an option for their treatment, and most of them said they would have been willing to enroll had they known it was possible.

There are several types of clinical trials. Each one is designed to answer the following questions. Treatment trials are the most commonly used in cancer research.

Once laboratory studies show that a new approach has promise, a phase 1 trial can begin. A phase 1 trial is the first step in testing a new cancer agent in humans. In these studies, researchers look for the best way to give people the new agent (for example, by pill or by injection), how often it should be given, and what the safest dose is. These studies also include special laboratory tests such as blood tests and biopsies to evaluate how the new agent is working in the body. Phase I cancer trials involve small groups of people with cancer.

Phase 2 trials continue to test the safety of the new agent, and begin to evaluate how well it works against a specific type of cancer. In these trials, the new agent is given to groups of people with one type of cancer or related cancers, using the dosage found to be safe in phase 1 trials. Phase 2 cancer trials usually have less than 100 participants.

Phase 3 trials focus on learning how a new treatment compares to standard, or the most widely accepted, treatment. Researchers want to learn whether the new treatment is better than, the same as, or worse than the standard treatment.

In phase 3 trials, participants have an equal chance to be assigned to one of two or more groups (also called "arms"). In a study with two groups:

The process of assigning participants to groups is called randomization.

Phase 4 trials are used to further evaluate the long-term safety and effectiveness of a treatment. Less common than phase 1, 2, and 3 trials, phase 4 trials take place after the new treatment has been approved for standard use.

An endpoint is what researchers will measure to evaluate the results of a new treatment being tested in a clinical trial. Research teams establish the endpoints of a trial before it begins.

It is important to note that endpoints differ, depending on the type and phase of the clinical trial. Examples of endpoints are:

NCI, pharmaceutical companies, medical institutions, and other organizations sponsor clinical trials. NCI often partners with pharmaceutical companies to develop new agents. Regardless of sponsor, clinical trials take place at universities, large medical centers, small hospitals, and doctors' offices. Individual physicians at cancer centers and other medical institutions can also sponsor clinical trials themselves.

All NCI-sponsored trials must meet all FDA and Office of Human Research Protection (OHRP) regulations for participant protection in clinical trials. NCI sponsors many clinical trials around the country that are conducted through four different programs.

Clinical Trials Cooperative Group Program - Clinical trials are often conducted through NCI cooperative clinical trial groups, which are networks of institutions that jointly carry out large clinical trials following the same protocols. Members of these groups include university hospitals, cancer centers, community physicians, and community hospitals. Cooperative groups develop and conduct new clinical trials that follow national priorities for cancer research. They conduct phase 3 trials as well as phase 2 trials.

Currently, there are 10 cooperative groups. The Coalition of National Cancer Cooperative Groups comprises many cooperative groups, cancer centers, medical institutions, community hospitals, physician practices, and patient advocacy organizations. The coalition was conceptualized and created to address critical challenges for the cooperative groups such as clinical trials design and experience, regulatory and managed care issues, and competition for federal funding. Through the coalition, physicians, payers, patient advocates, and patients have access to programs and information designed to improve the clinical trials process.

Community Clinical Oncology Program (CCOP) - These programs allow community physicians to work with scientists conducting NCI-supported clinical trials. Participation in the CCOP benefits laypeople and health professionals in the community as well as scientists in research centers.

Minority-Based Community Clinical Oncology Program (MBCCOP) - The MBCCOP provides members of ethnic and racial minorities with access to state-of-the-art cancer treatment, prevention, and control technology.

Cancer Centers Program - NCI cancer centers conduct clinical trials under an NCI-approved protocol review and surveillance mechanism. The Cancer Centers Program consists of more than 50 NCI-designated cancer centers involved in many different cancer research efforts. Cancer centers also participate in at least one cooperative group.

Clinical Grants Program - Many clinical trial protocols are carried out under the direct support of an NCI peer-reviewed grant.

Several resources are available to help you locate clinical trials, including the MMRF's own Clinical Trials Monitor. You can also call 1-800-4-CANCER (1-800-422-6237) or 1-800-332-8615 for TTY assistance.

Pharmaceutical and biotech companies conduct their own trials, both locally and nationally. They may have as partners universities, hospitals, NCI, or local doctors. These trials are subject to the companies' own review panels and to an Institutional Review Board (IRB), which may be local or national in scope.

Often times, individual physicians at single institutions will carry out their own clinical trials using their own research protocols. These are not multi-institutional trials. Clinical trials that are designed and sponsored by a single institution must submit their protocols, consent forms, and other documentation to an IRB. Only after IRB approval can the process of patient accrual begin.