What are the Phases of Clinical Trials?
Phase I: In Phase I clinical trials, researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects. Phase II: In Phase II clinical trials, the study drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety. Phase III: In Phase III studies, the study drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments and collect information that will allow the drug or treatment to be used safely. Phase IV: Phase IV studies are often done after the drug or treatment has been marketed. These studies continue testing the study drug or treatment to collect information about their effect in various populations and any side effects associated with long-term use.
Clinical trials are conducted in phases. The trials at each phase have a different purpose and help scientists answer different questions. Phase I: Researchers test a new drug or treatment in a small group of people (20-80) for the first time to evaluate its safety, determine a safe dosage range and identify side effects. Phase II: The study drug or treatment is given to a larger group of people (100-300) to see if it is effective and to further evaluate its safety. Phase III: The study drug or treatment is given to large groups of people (1000-3000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely. Phase IV: Post marketing studies delineate additional information including the drug’s risks, benefits, and optimal use.
Clinical trials are conducted in phases. The trials at each phase have a different purpose and help scientists answer different questions: In Phase I trials, researchers test a new drug or treatment in a small group of people (20-80) for the first time to evaluate its safety, determine a safe dosage range, and identify side effects. In Phase II trials, the study drug or treatment is given to a larger group of people (100-300) to see if it is effective and to further evaluate its safety. In Phase III trials, the study drug or treatment is given to large groups of people (1,000-3,000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely. In Phase IV trials, post marketing studies delineate additional information including the drug’s risks, benefits, and optimal use.
