Testing new medicines

For every drug we investigate, we carry out a series of clinical trials to test its potential as a new medicine.

Typically, we compare the potential drug against something with no effect—a placebo. Sometimes the investigation compares the test drug against medicines already in use.

The placebo looks like the drug being tested—a pink tablet, a colorless liquid. The patients don't know whether they're taking the real drug or the placebo—in fact, usually even the researchers don't know which patients receive the drug and which get the placebo. This is done to help make sure that the results aren't affected by the researchers' or the patients' opinions. Research on potential new medicines is divided into phases, which involve different types of studies or clinical trials.

Phase I trials typically involve healthy volunteers. These trials study the safety of the drug and its interaction with the body—for example, its concentration and duration in the blood following various doses. These trials begin to tell us whether the drug inhibits or exaggerates the effects of other medicines that might be taken at the same time.

Phase II studies enroll patients with the illness that the drug is intended to treat. These trials tell us whether the drug is effective in treating the illness—and at what dose. Sometimes these trials give us a chance to look at the drug in different illnesses.

Phase III trials are the largest part of the development. In Phase III trials we establish efficacy and safety more precisely, in ways that allow a regulatory agency—like the FDA in the United States—to approve the test drug as a medicine that's available for patients.

Research doesn't stop there

Clinical trials can go on even after a drug has been approved. Phase IV trials may test the medicine for other potential uses or tell us more about its safety.

One clinical trial often can't tell enough about a drug—so we conduct several trials, with different designs, to determine the potential of an investigational drug and its best use. That's why we perform a thorough analysis of studies. The prescribing information, ultimately approved by government agencies following their own analyses, defines the appropriate use of the medicine.

Did you know?

• It takes 10 to 15 years to take a drug from the lab to the pharmacy¹
• There are more than 5,000 patients in clinical trials²
• Clinical trials produce 100,000 pages (or more) of data³

References