Eye Conditions
Questions to ask your doctor or the researcher conducting the research study
Phases of Medical Research
Medical research studies are classified into a few different phases. Each phase has a different focus, but all work towards the goal of finding a new or improved treatment. These phases include:
Phase 1 Research Studies
In Phase 1, a new drug or treatment is tested on a small group of people — usually about 20 to 80. The new treatment has already been tested for safety in the lab and animals and has shown to have good potential for helping humans. It has also been submitted to a government regulatory agency and approved for use in human testing. The purpose of this phase is to find out if the treatment is safe for humans, and if so, how much should be given and how often the medication should be dosed per day. Those who participate in Phase 1 Studies are watched very closely (usually requires overnight stays), and the researchers record and evaluate any side effects that may happen after individuals have taken the study drug.
Phase 2 Research Studies
In Phase 2, a larger group of people receives the drug or treatment. There can also be a placebo group that does not receive the new investigational medication or treatment. The main purpose of this phase is to find out whether or not the new treatment is effective in treating the patient’s disease or medical condition. The safety of the drug or treatment continues to be studied in this phase, and any side effects are carefully documented and reviewed.
Phase 3 Research Studies
A larger group of people are involved in Phase 3 studies. Those who participate in Phase 3 are usually randomly assigned to different groups. In one group, up to a few thousand people will receive the new treatment. Another group receives the standard treatment for the same medical condition or receives a placebo. This is called the “control” group. The side effects and treatment success in people receiving the new treatment are compared to those in the control group. This helps the researchers know if the new treatment is safer and more effective. During this phase, researchers will continue to collect information about side effects and also study how often the condition returns and the effects of the treatment on the patient’s quality and length of life. After Phase 3 studies are completed, a new medicine or device may be submitted to the FDA or other governing agency to be reviewed and considered for approval.
Phase 4 Research Studies
Once a new treatment has been approved, there may be additional clinical studies performed. These are called Phase 4 studies. These studies are conducted for several reasons. One of these is to find out how effective the treatment is in different groups of people — such as those of the same race or age group. Another is to see if the treatment can be more effective if administered differently. For example, a pill can be changed to a topical cream for a more direct approach to muscle/joint pain. Information is also gathered about the long-term effects of the treatment.