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Scientific Review

Each clinical trial that is funded by the federal government must be reviewed by scientists from relevant fields before people can enroll. This expert review ensures that the trial is based on sound science. Though not required, many other clinical trial sponsors, such as drug companies, also seek expert advice on the scientific merit of their trials before opening them.

Institutional Review Boards (IRBs)

IRBs also review clinical trial protocols before they can accept patients. The board members make sure that the risk of harms in a trial is low and that any harms are reasonable when compared to the possible benefits. They also closely watch the ongoing progress of the trial from beginning to end and must review them at least once a year. IRBs can require changes to the protocol—or even stop the trial—if necessary to ensure the safety of people enrolled.

Federal rules require that each IRB include at least five people. It must include:

  • one scientist
  • one person who is not a scientist
  • one person who is not connected to or not related to someone who is connected to the site where the trial is taking place

IRBs can also include doctors, nurses, social workers, chaplains, patient advocates, and other health care or community professionals. All members of an IRB are required to understand the IRB’s purpose, functions, and responsibilities, as outlined in federal regulations.

In most cases IRBs are located at the site where the trial is to take place. Many sites that carry out clinical trials have their own IRBs. A clinical trial that is taking place at more than one site often undergoes review by a single IRB, also called a central IRB. The central IRB conducts reviews for all the sites taking part in the trial and works in agreement with each site's local IRB.

Data and Safety Monitoring Boards (DSMBs)

Some clinical trials - especially phase 3 clinical trials, which often involve many sites - use a Data and Safety Monitoring Board (DSMB). Like IRBs, these boards review the progress of a clinical trial and monitor the safety of those taking part in the trial. They also review data on the effectiveness of the trial interventions. Each trial has only one DSMB.

A DSMB is a group of doctors, statisticians, and others who are independent of the people, organizations, and institutions that are sponsoring, organizing, and conducting the clinical trial. Board members are experts in clinical research and clinical trials. They ensure that trial data are complete. They can stop a trial early if safety concerns come up or if the main research question is answered earlier than expected. Stopping a trial early because the main research question has been answered may make it possible for people who are not in the trial to access an effective intervention sooner. 

Office for Human Research Protections (OHRP)

OHRP protects people who take part in research and provides leadership for many federal agencies that carry out research involving people.

OHRP enforces important regulations for patient protection in clinical trials, called the Common Rule. These regulations set standards regarding:

  • The informed consent process
  • IRB formation and function
  • The involvement of prisoners, children, and other vulnerable groups in research

Food and Drug Administration (FDA)

FDA plays a role in protecting people who take part in research and ensuring the integrity of data from trials. FDA can remove researchers from conducting clinical trials when they repeatedly or purposely do not follow the rules intended to protect patients or when they have not ensured data integrity.

FDA approves new drugs before they can be sold which helps:

  • Prevent fraud
  • Ensure that drugs work as they should
  • Make sure the drug’s health benefits outweigh their risks
  • Reviewed: