Phase 4 Clinical Trials

During phase 4 clinical trials the goal is to continue, over time, studying the safety and efficacy of a drug that has already been approved by the FDA. This phase of the clinical trial process is not done as commonly as Phase 1, Phase 2 and Phase 3 clinical trials. Researchers continue to keep track of and record side effects, new and already discovered, that occur in people who are taking the medication.

The FDA does not always require all drug manufacturers to conduct his phase of the clinical trials for all drugs, but if they (the FDA) wants to be sure that there are no other side effects that weren't discovered prior to approval... or, if they want a better assessment of the seriousness of known side effects, they will require a drug manufacturer to conduct this phase of clinical trials.

Phase IV clinical trials are also called Post-Marketing Surveillance Trials. Sometimes, the results of phase IV clinical trials can result in additional restrictions being placed upon the drug's use or in the drug being ultimately withdrawn and taken off the market. Other key areas of research during this phase include:

• Cost-effectiveness: this means basically assessing the degree to which the drug treats the disease for which it has been approved at an acceptable cost to users
• Epidemiological data: assessing the drugs safety and efficacy within large and diverse user populations
• Pharamcoeconomics: assess the cost-benefit ratio (financial costs as well as quality of life) of the approved drug in comparison with other similar drugs

Phase 4 Clinical Trials Snapshot

• Goal: What happens when the drug hits the market?
• Number of Participants: thousands
• Duration: ongoing
• Outlook: may result in added restrictions, market withdrawal, or continued use as is

Extreme remedies are very appropriate
for extreme diseases.
- Hippocrates

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May 25, 2009

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