Types and Phases of Clinical Trials

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Specific Trial Information

Type of Clinical Trials

Not all clinical trials have the same goals. Understanding the question the researchers are trying to answer can help you decide whether you want to be in a study or if you want your child to be in a study. There are several different types of clinical trials which are described below:

  • Treatment trials test experimental treatments, new combinations of drugs or new approaches to surgery or radiation therapy. Treatment trials can answer questions like:
    • Can new treatments help people with Duchenne?
    • What treatments work best for people with Duchenne?
  • Prevention trials look for better ways to prevent disease or prevent a disease from returning. These approaches may include medicines, vaccines, vitamins, minerals or lifestyle changes.
  • Natural History trials (see video for more info) watch people over time to see which symptoms they have and how the symptoms of the disease change over time.  Natural history studies can be used to find out which symptoms of Duchenne and Becker are common and which are less common.  Natural history studies answer questions like:
    • How do the symptoms of Duchenne change as boys get older?
  • Screening trials test the best way to detect certain diseases or health conditions.
  • Quality of life trials look for ways to improve the comfort and quality of life for people. Quality of life trials answer questions like:
    • What kind of physical therapy techniques help people with Duchenne walk for a longer peroid of time?
  • Genetic studies are designed to find the Glossary Link gene changes that cause a disease or symptom.  These studies can also help provide information about how a gene works which can help researchers develop new ideas for treatments. Genetic studies answer questions like:
    • Which mutations cause more severe heart disease in people with Duchenne?
    • Are there mutations in other genes that cause symptoms similar to those seen in Duchenne?


What are the Phases of Clinical Trials?

Clinical trials are conducted in phases. The trials at each phase have a different purpose and help answer different questions. Today, new drugs and medical devices must go through several phases of clinical trials before being approved for use.

Phase PurposeOther info
Pre-Clinical Assesses safety and biological activity in lab only; can use tissue and/or animal models
Clinical trials
Phase I Tests for safety in humans and to determine a safe dose in humans, but typically a small group only
Phase II Tests if treatment seems to be effective and to look for any side effects in humans, usually larger group than phase I
Phase III Tests if treatment is effective in a larger group of people as well as look for any side effects and potentially compare experimental treatment to other commonly used treatments in humans, typically larger group than phase II
Phase IV (Post Marketing) Collects information on risks, benefits and optimal use in humans, after therapy is approved