FDA adds boxed warning to prevent Plavix drug injury

If you take Plavix, you’ll want to read this. Apparently, some patients are not responding to the medication, leaving them unprotected against heart attacks and strokes.

The AP (3/13, Perrone) reported that the FDA “is adding its strongest warning to the label for Plavix [clopidogrel bisulfate], cautioning that some patients do not respond to the blockbuster blood thinner.” According to the Los Angeles Times (3/12, Maugh) “Booster Shots blog,” the “warning indicates that the drug is dangerous only in the sense that it doesn’t work in” certain “patients and thus may leave them unprotected against heart attacks and strokes.”

Specifically, some patients have a difference in a liver enzyme known as CYP2C19, which helps to convert Plavix to a form that the body can use, Dow Jones Newswire (3/12, Dooren) reported. Notably, FDA officials said CYP2C19 tests typically cost less than $500.
Robert Temple, deputy director for clinical science at the FDA’s Center for Drug Evaluation and Research, said, “What there hasn’t been is a clear test of whether you can take people who are poor metabolizers, double their dose and do just as well,” according to Bloomberg News (3/12, Peterson, Larkin).