Takeda: Dexilant, Prevacid have less inhibiting effects on Plavix's efficacy than counterparts

NEW ORLEANS — Studies have indicated that proton-pump inhibitors, used for treating gastroesophageal reflux disease, reduce the efficacy of a popular blood-thinning drug, but Takeda Pharmaceuticals North America announced on Tuesday the results of a new study indicating that its own PPIs may have less of an effect.

The 160-patient study, presented at the American College of Cardiology’s 2011 annual scientific session in New Orleans, indicated that Takeda’s Dexilant (dexlansoprazole) and Prevacid (lansoprazole) had less of an inhibiting effect on the efficacy of Sanofi-Aventis’ and Bristol-Myers Squibb’s Plavix (clopidogrel) in healthy subjects than AstraZeneca’s PPI Nexium (esomeprazole).

“We conducted this study to look at the effect of select PPIs on Plavix and add to the growing body of evidence on the potential interaction between these drugs,” lead study investigator and Harvard Medical School professor of pediatrics Alan Michelson said. “We found that in healthy subjects, the co-administration of Plavix with dexlansoprazole or lansoprazole reduced the antiplatelet effect of Plavix less than the co-administration of Plavix with esomeprazole.”

According to studies, PPIs may inhibit the liver enzyme CYP2C19, which is involved in the body’s metabolism of Plavix, thus reducing the drug’s effectiveness. In November 2009, the FDA warned against using Plavix with prescription and OTC formulations of AstraZeneca’s Prilosec (omeprazole) in response to the findings.