A Black-Box Warning for Plavix. Confusion May Follow
The FDA says it added its strongest warning today to the label of the widely used bloodthinner Plavix, Bristol-Myers’ best-selling drug, to help physicians treat patients correctly. But the warning could make doctors’ job more difficult.
Docs prescribe Plavix to reduce the risk of heart attacks, strokes and other serious heart problems. The drug prevents dangerous blood clots that can cause those conditions. As a growing number of studies has demonstrated, however, Plavix doesn’t work well in certain patients - those with a genetic variation that makes it difficult for them to metabolize the drug.
The FDA says between 2% and 14% of Plavix users don’t respond well to the drug and might benefit from alternative treatment. Hence the new so-called black-box warning.
Genetic testing could identify the poor responders. But most doctors aren’t well equipped to do genetic testing. They don’t have quick access to the tests. Even if they did, they might not have time in the cases of many patients to wait for results to come back.
What’s more, the FDA has approved only one genetic test, Roche’s AmpliChip, to look for the variation, but not specifically for determining treatment with Plavix. Many laboratories offer other tests, whose quality the […]
Read more this great post here
