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![](images/global/clr_pxl.gif) | What are the different types of clinical trials?![](images/global/clr_pxl.gif) | There are four different types of clinical trials:
Phase I, Phase II, Phase III, and Phase IV.
Phase I - is the first time they have tried the drug in people
- tests for the drug's safety and helps find the right dose
- may ask for frequent tests or a stay in the hospital to check for safety and effectiveness
- lasts a fairly short time
- has a small number of patient volunteers
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Phase II - happens when early studies show that the drug may work well to fight hepatitis C
- tests for safety and effective dose level
- lasts longer than Phase I trials
- tries to find out what kind of side effects you get with this medicine
- has several hundred patients
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Phase III - happens if the drug worked well in Phase I and II
- compares standard treatments (medicines that you can already get by prescription)
or sugar pills (placebos) with the new medicine
- may last longer than Phases I and II
- looks for ways to reduce the side effects and improve the quality of your life while
you are taking the medicine
- is the last phase of study before a drug is sent to the FDA
- has many patients (sometimes thousands)
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Phase IV - happens when the drug is already available by prescription
- happens less often than other phases
- checks other safety issues and long-term side effects
- may be used to check higher or lower amounts (or doses) of the medicine
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Reviewed/Updated Date: February 8, 2007 |
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