Frequently Asked Questions About Clinical Trials

What is a clinical trial?
Why are clinical trials important?
Why might I want to participate in a clinical trial?
How do I participate in a clinical trial?
How are clinical trials conducted?
Why are clinical trials divided into phases?
For more questions about clinical trials

What is a clinical trial?

A carefully designed, systematic study of the safety and/or effectiveness of new, often innovative, healthcare options. A clinical trial is sometimes called a clinical research study. Clinical research studies often try to determine whether new medicines, procedures, equipment or therapies are safe or will help in treating, diagnosing, preventing or caring for people with specific illnesses or conditions.
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Why are clinical trials important?

  • To find new advances in medicine
  • To find new ideas or approaches for treatment
  • To identify safe and effectiveness of treatments
  • To receive FDA approval for use of new drugs or devicesTo find out which existing treatments might be better for certain patients, which might be the most cost-effective, or which ones might be easier to give
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Why might I want to participate in a clinical trial?

There are many reasons why people participate in clinical trials, but here are a few reasons:

  • To help others
  • To help advance science or knowledge about a particular disease or treatment
  • To possibly improve their own health
  • To benefit from having a research team involved in their care
  • To receive treatment options that might not otherwise have been available to them or a physician outside the research facility
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How do I participate in a clinical trial?

Either search trials locally or nationally to find a trial (for instance for a specific disease of interest). Become a volunteer by signing up at
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How are clinical trials conducted?

Study Protocol

  • The study protocol is developed and approved before the study begins and includes the entire plan of the research study
  • The study protocol is designed to answer any questions you may have about the study
  • The study protocol safeguards medical and mental health of patients

Types of Studies

  1. Testing one treatment in one group of patients
  2. Testing two or more very similar groups who each receive a different treatment option such as:
  • Treatment of interest
  • Standard treatment for the disease (active control)
  • Inactive substance (placebo control)
  • No treatment at all
  • Randomized- Where the patient is assigned to either a treatment or a control group by chance

A study where the patient(s) are unaware of the treatment they are given, but the researchers know what treatment each patient is being given

A study where both the patient(s) and researchers are unaware of which treatment they are given

What else goes into conducting a clinical trial?

  • Doctor can remove you at any point from the study if the study treatment is not helping the patient
  • The patient can decide to withdraw at anytime
  • If the treatment is harmful or ineffective, or if one treatment is considerably better than the other the study will come to a halt earlier than anticipated
  • Results of a study are generally published in medical journals or on
  • Throughout the entire study, the patient’s personal doctor is kept up to date about their progress in the study
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Why are clinical trials divided into phases?

The four phases of clinical trials were designed because each phase has a special purpose in helping scientists answer different questions about the drug or therapy being tested.

What are the four phases of a clinical trial?

Phase I

  • New treatment is given to a small group (20-100)
  • Volunteers in Phase I trials are generally healthy volunteers
  • This phase helps determine the safety of the drug therapy by studying:
    • How much is given (dosage)
    • What side effects occurred, if any

Phase II

  • Medium size group (100-300)
  • This phase helps determine if the treatment has an effect on a particular disease state
  • Volunteers in a Phase II trial are typically those who have the disease or disorder of interest
  • If the treatment was determined to be effective in Phase II then it will move into Phase III

Phase III

  • Larger group (1000-10,000)
  • This phase compares the treatment with a placebo or with standard treatment(s) to determine which is more effective or if it is equivalent to the existing treatment
  • Phase III trials can last many years and involve thousands of volunteers
  • Once Phase III has been completed, the drug or device company will go to the FDA to request approval to sell the drug or device in the U.S. as a treatment for a particular disease

Phase IV

  • In Phase IV, the treatment has already been approved by the FDA and is ready for post-marketing
  • What do they look for during post-marketing?
    • To look at the treatment after it has been given to the general population to assess any side effects and safety issues that may not have been recognized in a Phase III trial
    • Continue to monitor the effects of the drug in a population of 3 million people in a Phase IV trial versus 3,000 people in a Phase III trial
    • Test to see if the drug may be useful to treat other diseases
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For more questions or to search National Clinical Trial Listings visit