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  1. Clinical Trials: What Patients Need to Know

Informed Consent for Clinical Trials

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To many, the term informed consent is mistakenly viewed as the same as getting a research participant's signature on the consent form. FDA believes that obtaining a research participant's verbal or written informed consent is only part of the process. Informed consent involves providing a potential participant with: 

  • adequate information to allow for an informed decision about participation in the clinical investigation.

  • facilitating the potential participant's understanding of the information.

  • an appropriate amount of time to ask questions and to discuss with family and friends the research protocol and whether you should participate.

  • obtaining the potential participant's voluntary agreement to participate.

  • continuing to provide information as the clinical investigation progresses or as the subject or situation requires.

To be effective, the process must provide sufficient opportunity for the participant to consider whether to participate. (21 CFR 50.20.) FDA considers this to include allowing sufficient time for participants to consider the information and providing time and opportunity for the participant to ask questions and have those questions answered. The investigator (or other study staff who are conducting the informed consent interview) and the participant should exchange information and discuss the contents of the informed consent document. This process must occur under circumstances that minimize the possibility of coercion or undue influence. (21 CFR 50.20.)

What is Informed Consent? 

As new medical products are being developed, no one knows for sure how well they will work, or what risks they will find.   Clinical trials are used to answer questions such as: 

  • Are new medical products safe enough to outweigh the risks related to the underlying condition?,

  • How should the product be used? (for example, the best dose, frequency, or any special precautions necessary to avoid problems),

  • How effective is the medical product  at relieving symptoms, treating or curing a condition.

The main purpose of clinical trials is to “study” new medical products in people.  It is important for people who are considering participation in a clinical trial to understand their role, as a “subject of research” and not as a patient. 

While research subjects may get personal treatment benefit from participating in a clinical trial, they must understand that they:

  • may not benefit from the clinical trial,

  • may be exposed to unknown risks,

  • are entering into a study that may be very different from the standard medical practices that they currently know 

To make an informed decision about whether to participate or not in a clinical trial, people need to be informed about:

  • what will be done to them,

  • how the protocol (plan of research) works,

  • what risks or discomforts they may experience,

  • participation being a voluntary decision on their part.

This information is provided to potential participants through the informed consent process.  Informed consent means that the purpose of the research is explained to them, including what their role would be and how the trial will work. 

A central part of the informed consent process is the informed consent document. The Food and Drug Administration (FDA) does not dictate the specific language required for the informed consent document,  but does require certain basic elements of consent be included.

Before enrolling in a clinical trial, the following information must be given to each potential research subject:
  • A statement explaining that the study involves research.

  • An explanation of the purposes of the research.

  • The expected length of time for participation.

  • A description of all the procedures that will be completed during enrollment on the clinical trial.

  • Information about all experimental procedures the will be completed during the clinical trial.

  • A description of any predictable risks.

  • Any possible discomforts (e.g., injections, frequency of blood test etc.) that could occur as a result of the research.

  • Any possible benefits that may be expected from the research.

  • Information about any alternative procedures or treatment (if any) that might benefit the research subject.

  • A statement describing:

    • the confidentiality of information collected during the clinical trial,

    • how records that identify the subject will be kept

    • the possibility that the FDA may inspect the records.

  • For research involving more than minimal risk information including

  • an explanation as to whether any compensation or medical treatments are available if injury occurs,

  • what they consist of, or

  • where more information may be found.

  • questions about the research,

  • research subjects' rights,

  • injury related to the clinical trial.

  • Research subject participation is voluntary,

  • Research subjects have the right to refuse treatment and will not losing any benefits for which they are entitled,

  • Research subjects may choose to stop participation in the clinical trial at any time without  losing benefits for which they are entitled.

  • Contact information will be provided for answers to :

  • A statement that:

When Appropriate, one or more of the following elements of information must also be provided in the informed consent document:
  • A statement that the research treatment or procedure may involve unexpected risks (to the subject, unborn baby, if the subject is or may become pregnant).

  • Any reasons why the research subject participation may be ended by the clinical trial investigator (e.g., failing to follow the requirements of the trial or changes in lab values that fall outside of the clinical trial limits).

  • Added costs to the research subject that may result from participating in the trial.

  • The consequence of leaving a trial before it is completed (e.g. if the research and procedures  require a slow and organized end of participation).

  • A statement that important findings discovered during the clinical trial will be provided to the research subject.

  • The approximate number of research subjects that will be enrolled in the study.

A potential research subject must have an opportunity to:
  • read the consent document,

  • ask questions about anything they do not understand. 

Usually, if one is considering participating in a clinical trial, he or she may take the consent document home to discuss with family, friend or advocate.

An investigator should only get consent from a potential research subject if:

  • enough time was given to the research subject to consider whether or not to participate

  • the investigator has not persuaded or influenced the potential research subject.

The information must be in language that is understandable to the research subject.

Informed consent may not include language that:
  • the research subject is made to ignore or appear to ignore any of the research subject's legal rights,

  • releases or appears to release the investigator, the sponsor, the institution, or its agents from their liability for negligence.

Participating in clinical trials is voluntary.  You have the right not to participate, or to end your participation in the clinical trial at any time. Read the informed consent document carefully.  Ask questions about any information you don’t understand or find confusing.

Draft Guidance: Informed Consent Information Sheet Guidance for IRBs, Clinical Investigators, and Sponsors



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