Clinical
trial:
Studies of safety and efficacy of a
drug,
device, or therapy on human beings. There are four clinical trial
phases:
- Phase I: Conducted on a small group of healthy patients,
lacking the disease which is the target of the study. In some
circumstances, diseases patients may be used.
- Phase II: Conducted on a small group of patients with the
disease which is the target of the study. Usually limited to a
narrow group of population, such as sex, age, or race.
- Phase III: Conducted on a broad group of patients with the
disease which is the target of the study.
- Phase IV: Additional studies of any type as directed by the
FDA
or other agency prior to or after approval of the new drug,
devise, or therapy.