What Are Clinical Trials?

A clinical trial is a drug study sponsored by a pharmaceutical or biotechnology company. There are cases, however, where health-related government agencies provide funding and other resources for a clinical trial. The purpose of these studies is to find out whether a medication is safe to use and effective against various diseases or medical conditions. In order to study the medication, several questions need to be answered first. For example, what patient population or disease is the drug meant to treat? What criteria should be used for accepting participants into the study? What general and disease-specific information are the study doctors going to obtain? Essentially, once these and other important study questions are answered, the study doctors (investigators) are chosen, the regulatory documents are approved, and the study is ready to begin.

Why are clinical trials important?

There are a several reasons why clinical trials are important. First, the participant may have a positive response to the study medication, and their disease or condition may improve. In addition, participants receive free laboratory and medical testing. More often than not, the study medication is in development because it works differently than other drugs on the market, and therefore, it may present an alternative course of treatment for the patient. Second, participation in a clinical trial helps manufacturers make informed decisions about whether to pursue getting a particular drug approved by the Food & Drug Administration (FDA). Finally, data from one patient (who completes the entire study) can be an important part of a drug development program. In the best case scenarios, these data can help get an exciting new drug approved by the FDA, and ultimately, continue the industry's efforts in developing medications that are safer, more effective, and work faster than any before them.

How are a participant's rights and safety protected?

The FDA is the governing agency that develops the policies and guidelines for all medical research, regardless of manufacturer, study phase, or drug type. There are also independent Institutional Review Boards (IRB) that review and approve all study-related documents, such as protocols, Informed Consent forms, physician credentials and eligibility, and patient recruitment materials, such as print advertisements and public service announcements.

What are the phases of the clinical trial process?

There are three primary phases an investigational drug has to go through before it can be approved by the FDA, and a fourth phase that an approved drug may enter.

Phase I

In this phase of a clinical trial, the manufacturer wants to find out how the drug works in healthy study participants. Mode of action (how the drug exerts its effects), safety, and side effects -- these are some of the main issues that are of the utmost concern to drug makers at this stage of the clinical trial process. It is important to note that in Phase I studies, the overall safety of the medication in patients has not been established.

Phase II

A drug reaches Phase II only when the FDA has reviewed the Phase I data and concludes that the drug is safe for patients, and that its clinical activity may be beneficial against a particular disease or condition. At this point, a larger group of patients are enrolled and condition- or disease-specific rating scales are used to record data.

Phase III

This is an important turning point for drug manufacturers. The medication has already past the rigorous testing and review process required by the FDA, and now it's ready to be studied in an even larger patient population, with even more advanced rating scales and clinical measures. In recent years, there has been a growing industry trend to not only measure clinical effectiveness at this phase, but also measure "real world" results. For example, if a patient shows clinical improvement after entering the study, how are their activities of daily living improving (e.g., the patient can work in the garden more often or attend their child's games on a regular basis)? Most medications that reach Phase III will at least be considered for approval by an FDA advisory board.

Phase IV

At this phase in development, the drug has already been granted FDA approval. Phase IV studies are often performed to either identify an additional use for an already approved drug, or to gather additional safety information from a larger group of patients. In some cases, Phase IV studies are implemented to establish effectiveness in a subgroup of patients, for example, patients over age 65.