Monitoring program finds serious, unreported adverse drug reactions

A monitoring program developed by a Northwestern University researcher has successfully identified a large number of previously unknown, serious and often-fatal drug reactions associated with 15 commonly used drugs, including Plavix®, thalidomide and drug-coated cardiac stents.

As described in an article in the May 4 issue of the Journal of the American Medical Association, the Research on Adverse Drug Events and Reports (RADAR) Project compiles information from reports submitted to the U.S. Food and Drug Administration’s database and reports by drug companies and independent researchers throughout the world. RADAR is funded entirely by government grants.

RADAR has proved to be a powerful new instrument that supplements existing FDA surveillance systems and has helped save hundreds to thousands of patient lives, said lead author Charles L. Bennett, M.D., who directs the adverse drug reaction surveillance program. Bennett is professor of medicine in the division of hematology/oncology at Northwestern University Feinberg School of Medicine and a researcher at The Robert H. Lurie Comprehensive Cancer Center of Northwestern University, as well as a physician at the Jesse Brown Veterans Affairs Medical Center and associate director of the VA Mid-West Center for Health Services Research and Policy Studies. RADAR reviews have been published in leading medical journals. Summaries of the reviews have appeared in the media, and in “dear doctor” product warnings and labeling changes sent by pharmaceutical companies.

In the period between 1998 and 2004, Bennett and a multidisciplinary group of RADAR investigators identified serious adverse drug reactions with 14 commonly prescribed drugs, and with cardiac stents, that affected almost 1,700 patients, 170 of whom died as a result of the reaction. The drugs and devices are commonly used, with more than 1 million individuals have been prescribed two of the drugs.

Adverse drug reactions were classified as resulting in death, severe organ failure or requiring major therapeutic interventions, such as cardiopulmonary resuscitation, liver transplantation or placing an individual on a respirator. One particularly severe drug reaction with a novel cancer drug was associated with 67 deaths.

Adverse drug and device reactions account for as many as 100,000 deaths annually. In general, more than half of the most serious adverse drug reactions have been discovered seven or more years after a drug has been marketed.

The recent withdrawal of Vioxx has led to calls for new and independent postmarketing surveillance programs such as RADAR.