Plavix effectiveness criticized in two new studies


A new study suggests some patients are more likely to experience greater clinical benefits and less risk of dangerous side effects taking Effient rather than the blood thinner Plavix.

Plavix is an anti-platelet drug prescribed to reduce the risk of stroke, heart attack, and possible sudden death due to dangerous blood clots. In a new released clinical trial called RESET, researchers at University of Rome carriers of the CYP2C19*2 allele found better clinical results taking a standard dose of the drug Effient than they did to a higher dose of Plavix.

The drug marketed by Bristol-Myers Squibb has been linked to dangerous side effects, including severe cerebral and gastrointestinal bleeding, in addition to Thrombotic Thrombocytepenic Purpura (TTP).

The study identified specifically those carries of that allele who have undergone percutaneous coronary intervention are more likely to have lowered platelet aggregation. According to a report at, the study also ” identified a possible platelet aggregation cutoff above which patients may be more likely to harbor genotypic variations in CYP2C19 that compromise their ability to respond to Plavix.”

Another study highlighted in the report noted that patients with two copies of the *2 allele did far worse on Plavix than patients with just a single copy.