Clinical Trial FAQs

Choosing to take part in a clinical trial, also known as a research study, is a personal decision. It is important to learn all about it before you decide.

These frequently asked questions give information that may find helpful as you consider taking part in a clinical trial.

What is a clinical trial?

A clinical trial, also known as a research study, is a type of research designed to learn more about how our bodies respond to drugs or other treatments. Researchers look at the results of many clinical trials to understand if a trial drug is safe and works well. Research studies may also find new ways to help prevent, detect, or treat health problems.

What is a trial drug?

A trial drug, also known as an investigational drug, or investigational medicine, is a new drug that is in the process of being studied and has not yet been approved for doctors to use to treat a disease. To be approved, a drug must be tested in many clinical trials to see if it is safe and works well to treat a disease in certain groups of people.

What are the phases of clinical trials?

Clinical trials move in phases to allow careful testing and ensure safety. Before a trial drug is given to people in clinical trials researchers study the drug in the lab and in animals. When lab and animal studies find the drug is ready to give to people, it goes through these phases:

  • Phase 1: Researchers study a trial drug in a small group of 20-100 volunteers (usually healthy people). Phase 1 trials focus on the drug’s safety and side effects, including:
    • How the body breaks down and removes the drug
    • How much of the drug is needed and how often
  • Phase 2: Researchers study a trial drug in a larger group of up to 500 volunteers (usually people with the disease or condition it’s designed to treat). Phase 2 trials focus on if the drug works and learn about any new safety concerns.
  • Phase 3: Researchers study a trial drug in very large groups of volunteers who have the disease or condition it’s designed to treat. Phase 3 trials gather more data on safety and how well the drug works in different groups of people and at different doses. Researchers may also compare the drug with usual or similar treatments to see if it works better.

After Phase 3 trials, government and regulatory agencies, such as the U.S. Food and Drug Administration (FDA), may approve the drug for use to treat a disease in the general public. Phase 4 trials track the safety of an approved drug (called a “medicine” after being approved). They also learn more about its risks, benefits, and how well it works over a long period of time.

What is a placebo?

A placebo is a look-alike substance that doesn’t contain any active drug.

If a clinical trial is “placebo-controlled”, this means that one group of participants will get the trial drug and another group, often called the control group, will get a placebo.

What will happen if I join the clinical trial?

Before you can join, the trial doctor and staff will tell you more about the purpose of the trial. You will also read and sign an Informed Consent Form (ICF). This document will tell you everything that will happen in the trial. You can ask the trial doctor and staff as many questions as you want before signing this form.

If you decide to join the trial, you may need to have some medical tests. The trial doctor will also review your medical history to make sure you are a good fit for the trial.

If you enroll in the trial, you will work closely with a team of trial doctors, nurses, and other research staff. You will have regular visits during the trial. The trial team will continue to follow your health and your response to the trial drug until the trial is over.

How are clinical trial participants protected?

There are rules to help protect the rights, safety, and well-being of people who volunteer for a clinical trial. These rules make sure trials follow strict scientific and ethical guidelines.

Before a trial can begin, a review board must review and approve the trial. This group is called an Institutional Review Board (IRB). An IRB is made up of doctors, scientists, and members of the community.

How will my personal data be used and protected?

The informed consent form will explain how the clinical trial staff will collect and use your personal data. Trial staff keep all information collected during and after the trial secure. Only the trial staff will be able to access your data. The trial staff will tell you what kind of personal data they’ll collect, and how they’ll use it.

If you have questions about what the trial staff will do with information they collect:

  • Talk to the trial staff - they can explain the rules that are in place to help keep your trial information private and secure
  • Talk to the trial site’s data protection officer if you have questions about how your personal data is handled and protected
  • Review the informed consent form for more information

After Phase 3 trials, government and regulatory agencies, such as the U.S. Food and Drug Administration (FDA), may approve the drug for use to treat a disease in the general public. Phase 4 trials track the safety of an approved drug (called a “medicine” after being approved). They also learn more about its risks, benefits, and how well it works over a long period of time.

What are some of the risks and benefits of joining a clinical trial?

There are risks and benefits to joining any trial. The trial doctor will explain the possible risks and benefits of being in this trial. During a trial, researchers may learn more about how well an trial drug works. They also may learn about possible safety risks. Researchers do not always know all the possible side effects of a trial drug.

Before joining a trial, you should consider all risks and benefits. Gather as much information as possible before making your decision. You may want to speak to your regular doctors about possible treatment options. You may also want to speak with family members or close friends to help you decide.

Why take part in a clinical trial?

A clinical trial is a research study that tries to answer questions about how drugs work in the people who take them. Researchers run trials to test if a trial drug is safe and works well. These trials may help doctors find new ways to help prevent, detect, or treat health problems. Information learned from this trial may help other people in the future.

What questions should I ask the clinical trial staff before joining a trial?

After reading through this, you may still have questions. To help start a conversation with your trial doctor or nurse, you may want to ask these questions:

  • What is the purpose of the clinical trial?
  • Why do researchers think the trial drug or treatment may work? Has it been tested before?
  • What are the possible short-term and long-term benefits?
  • What are the possible short-term and long-term risks, such as side effects?
  • How long will the trial last?
  • How often will I have to visit the hospital or clinic?
  • What tests or procedures will I have?

Ask the trial doctor or staff all of your questions to help you make an informed decision about taking part.

Can I leave the clinical trial after I start?

Yes, you may leave the trial at any time, for any reason. Taking part in any trial is up to you. Talk to the trial doctor and staff any time about concerns and questions you may have. If you decide to leave the trial early, the trial doctor may ask that you return to the trial site for a final visit.

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