Clinical Trials (cont.)

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What are the phases of a clinical trial?

Clinical trials are broken down into phases, with each phase having a different purpose within the trial. Phase I trials involve a small group of people (20-80) and are concerned with determining a safe dose of the drug being studied as well as its potential side effects. In Phase II, the treatment or drug is tested in more people (100-300) for further evaluation - this time, determining the time of the drug or treatment's effectiveness against the disease for which the patient is being treated. Even more people (1,000-3,000) are participants in Phase III of a trial, when the intervention is compared to standard treatments and further information is collected about safety and side effects. In Phase IV trials, conducted after a treatment has been approved for specific indicated conditions by the FDA, post-marketing studies are carried out to collect more information about the optimal use of the drug or treatment and to further evaluate its side effects.

Clinical trials may be carried out in different locations, including hospitals, clinics, individual physician practices, university health centers, or community health centers.

How can one find out what clinical trials are currently being conducted?

The web site is a searchable database of federally and privately funded clinical trials being conducted in the U.S. and around the world. Your doctor or health-care team may also offer information about clinical trials that are currently under way for your specific condition.

Medically Reviewed by a Doctor on 9/23/2015

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