Participant Safety in Clinical Trials

Clinical trials are carefully designed studies that investigate whether a new drug, medical device, or procedure would be beneficial to people with a certain disease or condition. Before joining a clinical trial, you may ask yourself, “Are clinical trials safe?” While each trial has its own set of risks, investigators take precautions to minimize them according to strict rules and make sure your rights are protected during a trial.

A Brief History of Clinical Trials

Clinical trials, in one form or another, have been used in the United States since the 1940s for studying new drugs, medical devices, and medical procedures. After World War II, doctors began performing controlled studies for antibiotics using participants who received either a new treatment or placebo (“fake drug”) to determine how well the treatment worked. While these trials weren’t as strict as they are today, they set the foundation for how human research is conducted in the United States.1

The FDA enacted the National Research Act in 1974 to establish the basic rules for human research. Establishing these rules was a reaction to the breach of public trust and ethics from the Tuskegee experiments, which ran from 1932 to 1972 on uninformed African American men with syphilis who weren’t given access to proper resources or treatments.2 The government rules governing human research continue to change over the years to address new concerns with clinical trials, ensuring the safety and health of participants.

Risks of Participating in Clinical Trials

While every effort is put into making sure participants are as safe as possible, there are some risks associated with participating in a clinical trial. These trials are done to determine whether a drug is safe and effective, so there are always risks and unknowns in a study. Depending on the phase you choose to participate in, there may be different risks to expect.

Side Effects and Time Commitment

Phase 1 clinical trials are first-in-human studies, meaning that the drug is being tested for the first time in human subjects. Typically, phase 1 studies use healthy volunteers, or in cases of cancer treatments, people with a particular cancer type. Researchers will have a basic understanding of how the drug works from animal studies, but there is the possibility that a drug will work differently in humans. As a result, you may experience unexpected side effects that couldn’t be predicted from earlier studies. In rare cases, these have become serious or life-threatening. Investigators take precautions before and during a clinical trial to ensure there are as few unexpected complications as possible.3 Investigators must explain to participants that there are anticipated and unanticipated risks in participating in a clinical trial.

Phase 2 and 3 studies involve larger groups of participants who all have the disease or condition being treated. A drug that reaches these phases is generally safe to give to humans, and the investigators have determined dosing and how the drug is administered. Even after a drug reaches these phases, it’s possible that other, more rare side effects may start appearing. This is because these studies use a more diverse group of participants to build more data on the drug. It’s still possible to experience mild to severe side effects, depending on how the drug affects you.4

Some clinical trials may also require a larger time commitment than you’re used to when receiving treatments. This could involve getting more blood work done to monitor your levels, staying longer in the hospital during treatment, or visiting the clinic more often for your dosing schedule. Before deciding to join a clinical trial, be sure to think about the time commitment and the possible side effects you may experience while trying an investigational drug.3

Will an Investigational Drug Be Beneficial?

Many people choose to join clinical trials to try an investigational drug they think may be helpful. Oftentimes, these people have failed to treat their condition using currently available therapies or the standard of care. It’s important to note there’s no guarantee you’ll benefit from receiving an investigational drug during a study, but it may be possible. Many trials are double-blind, meaning both you and the doctor don’t know whether you’re receiving the investigational drug or a placebo (“fake drug”) or standard of care. This means you likely won’t know the benefits of a drug until after the study is complete.5

Monitoring Participant Safety During Clinical Trials

Before you join a clinical trial, a member of the investigational team will discuss the study with you. This includes information on the drug, expected side effects and potential complications, and testing that will be done. As a participant in a clinical trial, you have the right to learn about the study and how your rights are protected. Before you commit to participating in a study, you can talk to your family, friends, and your doctor to discuss the benefits and risks. Participating in a clinical trial is a big decision, and it should be the one that’s best for you.

Participants’ rights are protected by several committees that are required by the FDA for any clinical trials supported by federal funding. These boards, including an institutional review board and a data and safety monitoring board are there to ensure the clinical trial is ethical and that your health and safety are put first.

Institutional Review Board (IRB)

An institutional review board (IRB) is a group of people at a university or institution that helps to monitor clinical trials. IRBs are required for any research involving FDA regulated products to help ensure that the rights and welfare of people participating in clinical trials are protected.6,7

An IRB is made up of at least five members with backgrounds in science and research. At least one non-scientific member is also appointed, who is usually a community member. Together, the board reviews clinical trial procedures and has the authority to approve or deny them. They receive information on the proposed clinical trial, including:

  • How participants are recruited
  • Questionnaires, surveys, and tests that participants will take throughout the trial
  • The informed consent form that participants will read over and sign
  • How the investigators will protect the participants’ confidentiality

Once all of the information is submitted, the IRB will review it and consider the consequences for participants. These may be psychological, physical, economic, or social consequences, in addition to any benefits the participants and the scientific community may get.

The IRB will then approve or deny the proposed clinical trial. In some cases, they may request that changes be made before a study can begin. After approval, the IRB continues to monitor every trial yearly to ensure safety standards are still being met.

Informed Consent Process: Your Rights

Informed consent is an integral part of the clinical trials process in making sure you as a participant fully understand a study. This process involves much more than signing a consent form for your participation. A member of the research team for a clinical trial is required by the FDA and IRB to address information about the study, such as:8,9

  • The purpose of the clinical trial
  • How long the trial is expected to take
  • That participation is voluntary and that you have a right to be treated with a standard of care even if you refuse treatment
  • How your privacy will be handled throughout the trial, and that the FDA may review the trial’s records at any time
  • Your right to refuse treatment or leave a study at any time
  • Information for a contact person who can answer questions about the trial

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After you receive the paperwork for consent, you don’t have to make a decision right away to participate. If you’d like to discuss the forms with a family member or doctor, you can ask for copies to share. Clinical trial teams are required to give you an appropriate amount of time to review all information, and they can’t force you into taking part in a study. They’re also required to give you time during your discussion to ask any questions you may have and make sure you understand the study as much as possible.

If you choose to join a clinical trial, the team must also keep you updated as it progresses. As new information about the study becomes available, you’ll be notified. Participants can exit a clinical trial at any time in the study.

Questions to Ask When Considering a Clinical Trial

When researching participation in a clinical trial, examples of questions you might want to ask the investigator before committing include:

  • What will happen to me during the trial?
  • What are possible ways I might experience discomfort during the trial, such as blood work, injections, etc.?
  • What are the benefits and risks of participating in this study?
  • Will I receive any compensation for participation, or if I am injured during the trial?
  • What treatments or procedures may potentially benefit me as a participant?

Informed Consent for Children

In order to give your informed consent, you must be 18 years or older. For clinical trials involving children, this means that special considerations must be made. Since children under the ages of 18 can’t provide their consent, they may be asked for their assent. In short, this means that the child agrees to participate in the study. Dissent is given when the child refuses to participate in a study. Assent isn’t required in the same way informed consent is, but some IRBs may require it for children to participate in studies. Any child over the age of 7 can provide their assent/dissent.10

To gain assent, a member of the clinical trial team will talk to you and your child about the trial. As the parent or legal guardian, you’re required to give your informed permission for them to participate. The team will also explain the trial to your child in a level of language they can understand. They may also use videos, pictures, or other aids to explain what will happen during the study. Your child will then be encouraged to ask questions and talk it over. To make sure your child understands what the trial is about, you may be required to talk to the team several times before your child gives their assent or dissent.

Assent/dissent from a child may not be required in cases where:

  • The child is incapable of providing it
  • The treatment being studied is only available through clinical trials
  • The child will benefit from the trial

Data and Safety Monitoring Board (DSMB)

A data and safety monitoring board (DSMB) is made up of individuals outside an institution that review data from clinical trials. A DSMB is an unbiased group that looks at data collected during a trial to determine whether or not it should continue based on safety and efficacy. For example, if a study investigating a new drug shows that people are getting sick and their condition isn’t improving, the DSMB may make the recommendation to end (terminate) the study.11

Other responsibilities of a DSMB include:

  • Evaluating the quality and completeness of the data
  • Checking on individual study sites to make sure protocols are being followed
  • Looking at new research that may affect the safety of participants
  • Checking for protocol violations or breaches in confidentiality of the participants
  • Making sure the trial is recruiting and retaining participants

After looking over the data for a trial, a DSMB may suggest the investigators make changes to improve it, such as updating protocols based on new safety data. In some cases, the board may recommend the investigators end the study if the participants are not benefiting from it, or if the team cannot recruit enough people to participate. Smaller studies can’t provide enough data to understand the effects of a treatment.

The information provided in this article is not a substitute for the advice of qualified healthcare professionals. While we strive to publish accurate information, it is not possible to cover all potential scenarios, including drug or treatment effects, interactions, or usage. You should not rely solely on this article to determine whether a particular treatment, drug, or clinical trial is suitable for you or any other individual. Always consult a healthcare professional before starting or changing any treatments.