A clinical trial is a research study carefully conducted by pharmaceutical and biotechnological companies to answer specific health questions. Qualified investigators and other research professionals supervise clinical trials that are approved and thoroughly regulated by the U.S. government's Food and Drug Administration FDA. Clinical testing of a new drug is a step-by-step process that ensures patients to receive careful medical attention. Clinical trials can tell researchers which treatments are more effective than others, and ultimately help in the development of new drugs and treatment strategies.

Participants in clinical trials play an active role in their own health care as well as gain access to potential new treatments at no cost before they are available. Participants also help others by contributing to medical progress.

As part of the lengthy process of drug development clinical trials are conducted in phases (I to IV) - with different purpose and questions to be answered.

• Phase I: Scientists test drugs on small groups of healthy volunteers to evaluate its safety, determine a preliminary dose range, and identify potential side effects.


• Phase II: The study drug is given to a larger group of volunteers to test its effectiveness and to further evaluate its safety.


• Phase III: The investigational drug is given to larger groups of volunteers suffering from the targeted disease. The purpose is to demonstrate substantial evidence of effectiveness and safety of the drug. These studies usually serve as basis for the new drug approval process, performed by the FDA.


• Phase IV: Post marketing studies for additional information on the optimal use, efficacy, and tolerability.

This process includes several steps:

• A volunteer is screened for study eligibility. That is to find out if he/she meets the inclusion/exclusion criteria. The interested person will receive a physical examination, a review of the medical history, and a detailed description of the specific clinical trial.


• If eligible the volunteer will be enrolled in the study and randomized to either of the pre-defined treatment groups.


• The volunteer is asked to come in to the trial site for regular visits, where various tests are performed and the study drug is distributed.


• The final visit signalizes the end of the study for the participant.


• Some studies provide a follow-up period to gain further information on the long-term efficacy and tolerability he study drug.