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.

How is a clinical trial performed, and what sort of preparation is needed?

Before a clinical trial can be carried out, thorough preparation is necessary, including extensive reviews of the proposed trial, its methodology, and the goals of the trial. An Institutional Review Board (IRB) consisting of physicians, statisticians, researchers, patient advocates, and others must pre-approve every clinical trial in the U.S. The job of the IRB is to ensure that the trial is ethical, legal, and that the rights of those participating are fully protected. For example, individual participants' names are kept secret and not included in the results or publicly available information about a trial.

Every clinical trial has a strictly defined protocol that is approved by the IRB. A protocol describes what types of people may participate in the trial; outlines the exact the schedule of tests, procedures, medications, and/or dosages involved in the trial; and specifies the length of the study. Generally, doctors check the patient thoroughly at the start of the trial, provide instructions and directions for participation in the trial, monitor the patient during the actual trial, and remain in contact, sometimes with further monitoring after the trial is completed.

In many clinical trials, patients will be randomly assigned to a test group or a control group. The control group receives the standard and accepted treatment for a given condition, while the test group receives the experimental medication or treatment to be evaluated. When a trial is "double-blinded," neither the participants nor the treating doctors know if an individual patient is receiving the standard treatment versus the experimental treatment. Double-blinded trials offer the advantage of allowing the treating health-care team and the patient to make unbiased observations about patient progress and the effectiveness of the treatment being evaluated. A double-blind study is also referred to as a double-masked study. Results obtained from a randomized, double blind clinical trial are considered the most accurate and reliable types of results, and help those conducting the trial to draw the most accurate conclusions.

Medically Reviewed by a Doctor on 2/26/2014

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