Heartburn drugs like Nexium, Prilosec and other so-called proton-pump inhibitors interfere with the heart-protecting function of Plavix, according to a study presented at last week’s annual meeting of the American Heart Association.
Among its many benefits, Plavix reduces the risk of future heart attacks in patients that have already sustained one. It also reduces the risk of life-threatening blood clots in patients that have undergone coronary stenting or balloon angioplasty.
But in its retrospective, claims-based study of nearly 17,000 people who received Plavix following stent placement or angioplasty, pharmacy-benefits giant Medco Health Solutions reported that the subset also taking heartburn drugs had a 50% higher risk of heart attacks and other cardiac events.
It’s a vexing problem for physicians because heartburn, stomach ulcers and gastritis are common side effects of Plavix, and nearly half of all Plavix users take Nexium, Prilosec or another proton-pump inhibitor to minimize these side effects.
And it’s a high-stakes problem for the pharmaceutical companies that market these drugs. Plavix, which is co-marketed by Bristol-Meyers Squibb and Sanofi-Aventis, topped $4 billion in sales last year. Astra-Zeneca’s Nexium was the 4th largest selling drug in the US last year, with sales of $5.5 billion. The percentage of Nexium users also taking Plavix is unknown.
A separate study presented at the AHA meetings added complexity to the matter because it seemed to show that proton-pump inhibitors increased cardiac risk all by themselves.
Larry Lesko, the FDA’s director of clinical pharmacology told the Wall Street Journal that his department will begin investigating the matter shortly. Meanwhile, people who take Plavix and heartburn drugs should consult their physicians.