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What is a Clinical Trial?

A Clinical Trial is a research study that tests a new, unapproved drug or device to see if it is safe and to see if it is an effective treatment. Many clinical trials test a new treatment drug or device against a standard drug or device that has already been approved by the Food and Drug Administration. Every clinical trial is designed to answer a set of research questions. If you fit the guidelines for a trial, you may be eligible to take part. Each study enrolls patients with a certain disease or condition and a specific health status.

Should you participate in a Clinical Trial?

This is a big question. Finding answers and making decisions are often hard. Drugs that are not yet approved may be beneficial, but there are potential risks to receiving a treatment that has not yet been approved. It is important to discuss your treatment options with medical experts including your own doctor and with those close to you. Your personal doctor, who may be your family doctor, and other medical specialists can counsel you about your choices for standard treatment or clinical trials.

Talk to them and ask questions about the issues/situation/decision you are facing. If you understand your condition, you can work closely with your doctor to make the best decision for you. You may want to take a friend or relative along with you when you talk to your doctor about your care.

Important Questions to Ask about a Clinical Trial

If you are thinking about participating in a clinical trial, you may want to ask these important questions:

  • What is the purpose of the study?
  • What does the study involve? What kinds of tests and treatments will take place? (Find out what is done and how it is done.)?
  • What are the potential risks of the new treatment and are you willing to take risks that are not yet known?
  • How many people have already taken the medication? (A new medication early in development may have more unknown risks compared to a widely used medication that is being tested for a new indication. The number of people who have already taken a medication in studies can give you a better idea about the potential risks that you can weigh against the potential benefits).
  • What is likely to happen with your condition if you do, or do not choose this new research treatment? (What benefits/drawbacks will this new treatment have?)
  • What are other treatment options and their advantages and disadvantages? (Are there standard treatments for your case and how does the study compare with them?)
  • How could the study affect your daily life? What will be required of you?
  • What side effects could you experience from the study? (What are the side effects of standard treatment and/or from the disease itself.)
  • How long will the study last? (Will it require an extra time commitment on your part?)
  • Will you have to be hospitalized? If so, how often and for how long?
  • Will you have any costs? Will they be reimbursed? Will any of the treatment be free?
  • What are the options open to me if I am harmed/injured as a result of the research?
  • What treatment would you receive? (What effects could this have on the rest of your life?)
  • What type of follow-up care is involved with the study? (short-term vs. long-term)

What is Informed Consent?

Informed consent is required for all research studies. Informed consent means that as a patient, you are given information so you can understand what the risks and benefits may be in the trial. Through informed consent you can make an informed decision freely about whether you will take part in the study or not. The nature of the treatment is explained by the doctors and nurses (health professionals) in the trial. You are given an informed consent form to read and consider carefully. Ask any questions you may have. Then, if you agree to take part, you can sign the form. Of course, you can also refuse. Your standard treatment will not be affected if you decide not to take part in your doctor’s clinical trial.

The informed consent process is an ongoing process. If you enter a trial, you will continue to receive any new information about your treatment that may affect your willingness to stay in the trial. Signing a consent form does not bind you to the study. You can still choose to leave the study at any time without affecting your standard treatment.

Clinical trials must first be approved by an Institutional Review Board (IRB), usually located at the institution where the trial is being conducted. IRBs, designed to protect patients, are made up of scientists, doctors, clergy and other people from the local community. An IRB reviews a study to see that it is well designed. It ensures that there are safeguards for patients and that the risks associated with the treatment are reasonable in relation to the potential benefits, and most importantly, that the informed consent that you are asked to sign adequately informs you of the risks of the trial.

Any well run clinical trial, whether federally supported or not, is carefully reviewed for medical ethics, patient safety, and scientific merit by the research institution.

How are Clinical Trials designed?

Clinical trials are carried out in phases, each designed to find out certain information. Patients may be eligible for studies in different phases depending on their general condition and the type and stage of their disease. More patients take part in the later phases of studies than in the earlier ones.

In a Phase I study, a new research treatment is given to a small number of patients. The researchers must find the best way to give a new treatment and how much of it can be given safely. They watch carefully for any harmful side effects. The research treatment has been well tested in laboratory and animal studies but this phase shows how people will react. Phase I studies may involve significant risks for this reason.

Phase II studies determine the effect of a research treatment. Each new phase of a clinical trail depends on and builds on information from an earlier phase. If a treatment has shown safety and effectiveness in Phase II, it moves to Phase III. Here it is compared with standard treatment to see which is more effective. Often researchers use standard therapy as the base to design new, hopefully better treatments. Then in Phase III, the new treatment is directly compared to the standard treatment. In Phase IV studies, the new research treatment becomes part of standard treatment in patient care. For example, a new drug that has been found effective in a clinical trial may then be used together with other effective drugs or therapy.

Food and Drug Administration (FDA) Approval Process

If an investigator or a company wishes to carry out a clinical trial on a drug or device, they must first submit an IND (INVESTIGATIONAL NEW DRUG/DEVICE) application to the Food and Drug Administration (FDA). The FDA evaluates the application with the input of advisory committees. If the application is approved, the FDA permits the study to proceed with the enrollment of suitable subjects through the various study phases described above. Permission to proceed with the study also is dependent on the approval of the IRB which has jurisdiction over the particular site of the trial. All the data accumulated is reported back to the FDA including the incidence of all side effects and adverse events. The FDA sets up an Advisory Panel to evaluate the safety and efficacy of the drug or device. If the panel recommends that the drug/device is safe and beneficial, then it may approve its use in medical practice. The FDA then grants a license for the drug/device to be marketed or to be prescribed by a physician to treat patients.

Learn more about questions you should ask before taking part in a clinical trial.

Adapted from information prepared by:

U.S. National Library of Medicine
8600 Rockville Pike
Bethesda, MD 29894
National Institutes of Health

Last Reviewed: July 1, 2003

Evaluated and endorsed by:

Michael   Privitera, MD Michael Privitera, MD
Professor of Neurology
College of Medicine
University of Cincinnati