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FDA Adds Black Box Warning About Effectiveness to Label of Blood Thinner Plavix

By March 19, 2010July 17th, 2019Dangerous Drugs

According to the popular health information Web site WebMD, the U.S. Food and Drug Administration has ordered a “black box” warning for Plavix (clopidogrel), a blood thinning drug. That is the strictest safety warning the FDA issues. The move comes after research showed that the drug’s effectiveness at normal doses is substantially reduced in people who carry certain genes. This is bad news, because Plavix is prescribed to help prevent heart attacks, strokes, blood clots in patients with stents and other serious cardiovascular problems. Plavix is the second-best-selling drug in the world, so the number of patients affected could be very large. Patients who fall into this genetic group without realizing it are at risk for any or all of these problems, and as a pharmaceutical liability attorney, I hope that Plavix-taking patients talk to their doctors about this as soon as possible.
The FDA said 2% to 14% of patients have a gene that makes it harder for their livers to metabolize the drug, which means less of it gets into their bloodstreams. That was true for about 2% of white patients, 4% of black patients, and 14% of Chinese patients, the agency said. Doctors can find out whether a patient is a poor metabolizer of Plavix by using a genetic test. This test can also show if a patient will be an “intermediate responder” or a “hyper-responder” to the drug. Unfortunately, the test costs about $500, and the amount of time it takes to get the results varies from a few hours to several weeks. For patients who are at imminent risk of having a second heart attack or stroke, waiting for several weeks to find out whether Plavix will be able to help them is “not a good idea,” said the director of FDA’s office of medical policy, Dr. Robert Temple. PBS’ NewsHour blog The Rundown says that doctors do not typically order the genetic test before prescribing Plavix.
This is not the first time Plavix’s effectiveness has come under scrutiny. In November of 2009, the Wall Street Journal reported on studies that showed Plavix’s effectiveness was reduced when it was taken with some heartburn medicines. Use of heartburn medicines with Plavix is common because stomach bleeding and ulcers are common side effects of the drug. Ironically, the study found that taking a heartburn drug to treat Plavix’s side effects causes it to stop working properly and raises patients’ risk of heart attack and stroke by 50%. Earlier, in May of 2009, the FDA had warned patients and doctors about Plavix’s poor metabolizer problem by changing information on the drug’s label. The black box warning comes after the agency reviewed more data. The label asks doctors to “use the best information possible to treat their patients” and consider alternative treatments. Patients are cautioned not to stop the drug without talking to their doctors first.
As a dangerous prescription drug attorney, I am concerned that it took so long for this information to result in a serious warning. Plavix has been on the market for over a decade, and is a best-selling drug. With so many users, scientists have had a lot of opportunities to spot problems, so it would be interesting to know how much Bristol-Myers Squibb and Sanofi-Aventis, the companies that market Plavix, knew about these problems before the label changes. Would Plavix have become the second-best-selling drug in the world if patients and doctors knew they needed a $500 genetic test to find out whether it’s effective? How many people have had heart attacks or strokes while taking Plavix, thinking that they were taking the best medication available for their condition? If Bristol-Myers Squibb and Sanofi-Aventis knew of these problems and did not warn doctors and patients appropriately, they could be held responsible for harm suffered by patients who took their drug.

If you or a loved one has been seriously harmed by Plavix or another ineffective or dangerous drug, please contact an experienced drug defect lawyer at Carey, Danis & Lowe for a free consultation. At this meeting, we can hear about your case and discuss how you can hold drug companies legally and financially responsible for the dangerous drugs that they market. Call us toll-free at 1-877-678-3400 or contact us through our Web site.