Clinical Trials

An Introduction to Clinical Trials

Clinical trials are conducted in phases. The trials at each phase have a different purpose and help scientists answer different questions:

The four testing steps are as follows:

PHASE I	PHASE II	PHASE III	PHASE IV
In 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.	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.

Updated: 6-8-2003

Source: Clinicaltrials Gov.

Clinical Trial Studies

Clinical Trials for Hepatitis C	The NIH Clinical Studys
CenterWatch Clinical Trials Listing Service	Hepatobiliary Interest Group Active Clinical Studies
Quest Clinical Studies: Pegylated Interferon vs. Rebretron	UMHS - Gastrointestinal Clinical Studies
UF Hepatitis and Liver Diseases Clinical Trials	Welcome to MicroBioTest, Inc.
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