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Clinical Trials FAQs


What are the different phases of Clinical Trials?

Clinical Trials are performed in different phases. Each phase evaluates treatments in a slightly different way.
  • Phase I - These trials are used to determine the best dosage of a new drug to be used and if it is safe (side effects). These trials typically involve small numbers of volunteers, typically 20 to 80 people.
  • Phase II - These trials are used to determine if a drug or treatment is beneficial to patients with a specific disease and to continue to gather information about the safety of the treatment. These trials involve larger numbers of volunteers, typically around 100 to 300 people.
  • Phase III - If the drug or treatment appears promising, Phase III trials compare the experimental treatment to standard therapies that are already in use and approved by the FDA. This Phase of clinical trials tries to determine if the new drug or treatment is better than the current treatment and how the side effects of the two treatments compare.
  • Phase IV - These trials are post-marketing (After FDA approval) studies. Phase IV studies are used to gain more experience in evaluating the safety and efficacy of the drug or treatment in larger numbers of patients. These studies are also used to compare the drug/treatment with other available treatments and to evaluate the long term use of the drug/treatment.

Why are Clinical Trials needed?

Clinical Trials are the only reliable and objective way to determine the safety and effectiveness of experimental treatments including drugs and devices.  Clinical trials are also done to compare existing or "standard treatments" to determine which is better.  Clinical Trials are also used to determine different ways to use standard treatments so that they will be more effective with fewer side effects.  Without Clinical Trials the life saving treatments we have today would not be available. 

Why should I consider participating in a Clinical Trial?

Participating in a clinical trial is certainly a personal choice and the decision should be made after receiving information about the trial and discussing the information with you physician and/or other health care providers.

People decide to participate in a Clinical Trial for a variety of reasons. People who volunteer to participate in a clinical trial can gain access to promising treatments long before these treatments are approved for general use. Others participate in Clinical Trials because they have exhausted all approved treatment options which have not worked for them or they could not tolerate the side effects of the approved treatments. Other people participate in trials because the want to contribute to the advancement of medical knowledge.

Are Clinical Trials Safe?

For most trials, researchers, doctors, and other health professionals administer the Clinical Trials according to strict rules set by the Food and Drug Administration. The FDA sets the rules to make sure that people who agree to be in studies are treated as safely as possible

In addition to the Food and Drug Administration, other processes are put in place to protect research subjects.

Each Clinical Trial is reviewed by a group of people called the Institutional Review Board (IRB).  The Clinical Trial can not begin until the IRB is satisfied that the trial addresses an important scientific question and is ethically sound.  IRB's are groups made up of physicians, nurses, pharmacists, administrations, and other scientists.  The IRB also receives regular updates to make sure the study is being carried out as designed and that any safety issues are addressed.

To participate in a Clinical Trial, a patient must meet some very specific eligibility requirements.  In addition, an assessment of risk versus possible benefit is made.  If the patients risk is too high they may not be able to participate.

When treating patients on a study, the study team monitors participants very closely and will try to identify any potential side effects as quickly as possible.  It is likely that more tests and physical exams will be performed than would have been if the patient was not participating in a Clinical Trial.  If unexpected side effects should occur, the study team would be able to treat them quickly.  In some cases patients will have to be withdrawn from the study.