What is a Clinical Trial?

Clinical trials are research studies that involve human volunteers to answer a specific set of questions with the goal of finding a better way to safely and effectively prevent, diagnose, or treat a health-related condition. They can involve anywhere from a few volunteers to thousands and may be conducted in local region or across the nation or globe.

There are many different types of research at the heart of clinical trials. Some studies focus on the use of a new drug, a new surgical method or a new treatment, while others focus on using known therapies in new ways or testing a new combination of known therapies. The main types of clinical trials are:

• Treatment Trials – focus on experimental treatments, new combinations of drugs, or new approaches to surgery or radiation therapy.
  
  
• Prevention Trials – examine ways to prevent disease in people who have never had the disease or to prevent a recurrence of the disease. Approaches include medicines, vitamins, vaccines, minerals, or lifestyle changes.
  
  
• Diagnostic Trials – involve tests or procedures for diagnosing a particular disease or condition.
  
  
• Screening Trials – focus on the detection of diseases or health conditions.
  
  
• Quality of Life Trials – also known as Supportive Care Trials, they explore ways to improve comfort and the quality of life for individuals with a chronic illness.
  
  

There are also different phases of clinical research, each serving a different purpose:

• Phase I – Initially, a small group of people (20-80) are given an experimental drug or treatment and researchers evaluate its safety, determine a safe dosage, and identify side effects.
  
  
• Phase II – Next, a larger group of people (100-300) are recruited to test the effectiveness of the drug or treatment and further evaluate its safety.
  
  
• Phase III – After that, even larger groups of people (1,000-3,000) are enrolled to confirm the effectiveness, monitor side effects, compare the drug or treatment to commonly used treatments, and researchers continue to collect information that will allow the experimental drug or treatment to be used safely.
  
  
• Phase IV – Finally, additional information is collected by researchers including the drug or treatment’s risks, benefits, and best uses.