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Protecting People in Clinical Trials

Several safeguards are used to help protect people who take part in clinical trials. There are still risks involved with any study, but these safeguards try to reduce the risk as much as possible.

Research involving people is based on three values described in the Belmont Report:

  • Respect: All people should be respected. They have the right to choose what treatments they get.
  • Beneficence: Protect people from harm by giving the most benefit with limited risks
  • Justice: Try to make sure that all people share the benefits and burdens equally

Research staff and government groups are charged with making sure that these values are followed in clinical trials. A key part of patient protection is the informed consent process, which is described in Being in a Clinical Trial.

Safeguards in institutions

All clinical trials must be reviewed by special groups to make sure that people in the trials are protected.

Institutional review boards (IRBs)

IRBs make sure that people in clinical trials are protected and that federal laws are followed. In turn, the federal Office of Human Research Protections (OHRP; see below) makes sure that IRBs follow laws that direct their process. Before starting, researchers must send the clinical trial protocol (the plan that describes the study in detail) to the IRB for review. The IRB must decide if the study looks at a worthwhile question and ensures the safety of the people on the trial.

The IRB also makes sure that the informed consent form that people sign before going on a trial is accurate, complete, and easy to understand. Once a clinical trial begins, the IRB watches over it to look for problems.  If you are in a clinical trial, you can contact the IRB with any questions or concerns.

Data safety monitoring boards (DSMBs)

Data safety monitoring boards (DSMBs) are used for phase III (and some earlier phase) clinical trials. The job of the DSMB is to watch the progress and results of the clinical trial. The DSMB can stop a clinical trial before it is done if:

  • It becomes clear that the new treatment is much more (or much less) effective to allow all people on the clinical trial to get the better treatment
  • Safety concerns come up, such as risks being much greater than benefits, so that no one else is exposed to possible harm.

The clinical investigator

The clinical investigator is in charge of all parts of a clinical trial. In some settings this person is called the principal investigator, or PI. The main responsibility for patient safety in a clinical trial belongs to the clinical investigator. This includes letting the study sponsor know right away when severe side effects occur.

Government agencies

Office of Human Research Protections (OHRP)

The OHRP is the government’s main protector of people’s safety in clinical trials. The OHRP makes sure that the rules of informed consent, IRBs, and participation of people with special needs are followed. OHRP can stop clinical trials when problems are found. OHRP also teaches research sites and individuals to help them follow current clinical trial standards.

Food and Drug Administration (FDA)

The FDA has the final say about whether a new treatment is approved to be given to patients. Once phase III clinical trials are completed, the FDA reviews the results of all trials and decides if the new treatment is safe and effective enough to be approved.

The FDA is also involved during the clinical trial. Clinical trials for any new drug, device or treatment must be approved by the FDA before they can begin. The FDA also inspects (audits) sites doing clinical trials, especially if there’s reason to think that the site is not following proper procedures. If serious problems are found, the FDA can prevent a site or doctor from doing any further research.

It is important to note that the FDA is not involved in the study of all treatments. Clinical trials of treatments that are already on the market do not have to follow the same FDA rules. And substances considered to be dietary supplements do not need FDA approval. (Dietary supplement makers don’t have to prove their products are safe and effective.)

National Cancer Institute (NCI)

The NCI, part of the National Institutes of Health (NIH), pays for many cancer clinical trials. Plans for trials must be approved by the NCI before they get funded. The NCI also audits each site doing NCI-sponsored research to make sure the right procedures are being followed.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing. The Belmont Report. Accessed at on July 21, 2019.

National Cancer Institute. Clinical Trials Information for Patients and Caregivers. Reviewed February 6, 2020. Accessed July 29, 2020.

Office for Human Research Protections. Reviewed June 30, 2020. Accessed August 3, 2020.

Taking Part In Cancer Treatment Research Studies. Bethesda, MD: National Cancer Institute, 2016.

Van Norman GA. Drugs, devices, and the FDA: part 1: an overview of approval processes for drugs. JACC Basic Transl Sci.  2016; 1(3):170-179.

Last Revised: August 18, 2020

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