The U.S. Food and Drug Administration (FDA) announced that AstraZeneca's two top stomach drugs, Prilosec (omeprazole) and Nexium (esomeprazole) do not appear to heighten the risk of cardiac disease over the long term. The two drugs were suspected to generate an increased risk of heart attack and other heart diseases after AstraZeneca submitted just a few months ago the preliminary results of two long term small studies on patients with severe gastroesophageal reflux disease (GERD).

The results from the first study, a 14 year Prilosec (omeprazole) study, showed there were more heart attacks, heart failure and heart related sudden deaths among the patients who had taken the drug compared with the surgery patients. The other study done with Nexium (esomeprazole) also showed a difference between the drug treatment and the surgery group, but a recent update has denied the initial findings.

The Food and Drug Administration also received results from 14 other studies on omeprazole which actually showed fewer heart diseases in patients taking the drug. The FDA has thus said it will make a final decision on the safety labels of these drugs in a few months, after analyzing all the available data.

Difficulties have also been encountered because "the study protocols did not specify how heart problems, such as heart attacks, were to be defined or documented. As a result, evaluating the information that has been gathered about the safety of either drug in these studies is difficult."

"FDA's preliminary conclusion is that the observed difference in risk of heart attacks and other heart related problems seen in early analyses of the two small long-term studies is not a true effect," said the official statement titled "Early Communication About an Ongoing Safety Review: Omeprazole (Prilosec), Esomeprazole (Nexium)".