Home > Patients & Visitors > Health Library > Phases of a Clinical Trial
A clinical trial is done to find out if a medicine or treatment
is safe and works well for treating a certain condition or
medicine or treatment must go through three phases before it is
approved for use by the U.S. Food and Drug Administration (FDA). A fourth phase happens after the medicine or treatment has been approved.
New combinations of approved medicines can
be studied in phase II, phase III, or phase IV trials.
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineSpecialist Medical ReviewerMichael Seth Rabin, MD - Medical Oncology
Current as ofNovember 20, 2015
Current as of:
November 20, 2015
E. Gregory Thompson, MD - Internal Medicine & Michael Seth Rabin, MD - Medical Oncology
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