Clinical Studies: Testing New Medicines Clinical studies (clinical trials) are drug research studies with human volunteers that are conducted to ensure that a new medicine can be used safely and effectively to treat patients. Clinical study results are relied upon by the Food and Drug Administration (FDA) to establish the safety and efficacy of a new drug and to provide guidance to health care professionals on its proper use. Four Stages of Clinical Studies New drugs are first tested in the laboratory, then on animals. Only if laboratory and animal testing demonstrate that a drug product is reasonably safe can it be tested on human volunteers in clinical studies. The typical drug-development program has four phases, and each follows an FDA-approved protocol. These clinical studies are conducted by a health care team that includes doctors, nurses and other health care professionals, who check the participants’ health at the onset of the trial, give them instructions, and monitor them. • Phase I includes 30 to 100 healthy volunteers who are given small doses of the drug (under highly controlled conditions in specialized clinics). Broad safety issues are studied before testing the drug with patients who have the disease or condition. • Phase II tests 50 to 300 patients who have the disease or condition. The purpose is to see if the drug has some effect against the disease, to study the drug’s side effects, and to determine the most promising dose and dosing regimen. • Phase III tests, on average, 3,000 patients, but can test as many as 10,000 patients. These tests are designed to establish the safety and effectiveness of the drug in a large and diverse population. • Phase IV clinical studies consist of post-marketing studies to delineate additional information including the drug's risks, benefits, and optimal use. Ensuring Safety Clinical studies are carefully controlled. They follow a detailed, pre-set research plan, following extensive discussions with the FDA. FDA reviews the preclinical testing data, examines the research plan, and decides whether to give authorization to proceed in testing the new drug on humans. In addition to the FDA approval process, a local Investigational Review Board (IRB) reviews and approves all research involving human subjects. Participants joining a clinical study are asked to give their informed consent. The informed- consent process provides an explanation of the study, its purpose, procedures, risks, and benefits of a study. Once the clinical study has begun, information gathered from the study is regularly submitted to regulatory agencies for review. As the clinical study progresses, researchers may report the results at scientific meetings, to medical journals, and to the FDA (while maintaining the confidentiality of study participants). A study participant can withdraw from a clinical study at any time. Sponsoring Clinical Studies Clinical studies designed for approval of a new drug are sponsored primarily by pharmaceutical and biotech companies. However, clinical studies also may be sponsored by government agencies, such as the National Institutes of Health, and by non-profit organizations (e.g., American Heart Association).