Northwestern hematology and oncology Prof. Charles Bennett has led a team of researchers in discovering the potentially deadly side effects of 17 drugs that have been approved by the U.S. Food and Drug Administration.
Bennett’s project, named Research on Adverse Drug Events and Reports, looked at side effects from common drugs that have caused serious injury or death in some patients since the project’s inception in 1996.
“We wanted to identify serious, potentially fatal, drug effects that haven’t previously been recognized and to disseminate the information to the public, drug providers, doctors and the FDA,” Bennett said.
Bennett’s work prompted the FDA to issue physicians’ cautionary letters about several drugs and to put black-box warnings on others, including Plavix, an anti-clotting agent that has been on the market since 1998. In rare cases, Plavix can cause a collapse of the blood system.
Bennett began work on the project after his father’s best friend was hospitalized with a serious reaction to Ticlid, a predecessor of Plavix.
“We found 60 people just like her, and 20 of them had died,” Bennett said. “We realized that if we had not looked into this and done this work, nobody would have known about this.”
Since then, Bennett has used a $5 million grant from the National Institute of Health to research the potentially deadly side effects of several popular drugs, including Thalidomide. The drug originally was developed to treat leprosy but since has been used as a cancer medicine.
Bennett found that 20 percent to 30 percent of cancer patients who used Thalidomide while undergoing chemotherapy developed blood clots. He said the Thalidomide problem points to a larger drug safety issue called off-label drug use — a tendency for doctors to use drugs to treat conditions for which they were not developed.
“Every drug has a problem with risks and benefits, and many of these problems show up when the drug is used in circumstances that are different than those in which they were tested,” Bennett said. “But once the drug is on the market, any doctor can use any drug for whatever they want.”
Half of all cancer drugs and roughly a quarter of all other drugs are off-label, Bennett said.
The system of FDA approval can be flawed because of there are not enough researchers investigating drug safety, he said.
“The FDA has 110 people looking at drug safety,” Bennett said. “They have seven times that number of people getting drugs approved.”
In early 2004 Bennett wrote an article revealing potentially fatal side effects caused by Epoetin, a drug that treats anemia. Bennett criticized the FDA for its lack of drug safety research. Nine months later, the FDA revoked his access to the adverse drug-reactions database that he had been using.
“The FDA was under tremendous scrutiny for the childhood suicides (from the drug Accutane),” Bennett said. “They weren’t so excited in having other people getting their data. They wanted a more controlled approach.”
Bennett said he plans to use the database of the Veterans Health Administration, a firm that provides health care to 10 percent of the U.S. population, to continue his research. However, Bennett said he hopes to have a positive relationship with the FDA so that he can continue life-saving research.
“My concern is that right now, we don’t have any access to the data we used to use,” Bennett said. “My concern is that (this research) has saved several thousand lives, and while we are trying to figure this out, will we lose a couple thousand more?”
Reach Julia Neyman at [email protected].
