The US Food and Drug Administration (FDA) said yesterday that a preliminary review of new data on the safety of two stomach drugs made by AstraZeneca, Prilosec (generic name omeprazole) and Nexium (generic name esomeprazole) suggests that long term use of these medications does not lead to heart attacks and other heart related events. The agency said for the time being, until a final decision and recommendation is made in three months’s time, health professionals and patients should not change their current practice in the use of these drugs.
Prilosec and Nexium are proton pump inhibitors (PPIs) used to control stomach acid. They are taken by patients with a range of gastrointestinal conditions such as ulcers and gastroesophageal reflux disease (GERD). Some GERD conditions erode the lining of the food pipe (esophagus) and PPIs help to heal the erosions or stop them getting worse. Prilosec and Nexium are available in the US by prescription, although Prilosec is also dispensed over the counter for heartburn.
AstraZeneca submitted preliminary reports on two small long term studies on Prilosec and Nexium to the FDA and other regulators throughout the world in May this year.
The two studies involved patients with severe GERD who were randomly assigned to receive surgery or drug treatment.
The results from the 14 year Prilosec (omeprazole) study showed there were more heart attacks, heart failure and heart related sudden deaths among the drug patients compared with the surgery patients. This difference was noticed in the first year of the study and continued thereafter.
The other study on Nexium (esomeprazole), has now gathered 5 years of follow up on patients but is not yet completed. The initial results also showed a difference between the drug treatment and the surgery group, similar to the Prilosec study, but a more recent update has since shown that the incidence of cardiovascular events is largely similar between the two groups.
Also, since May, as well as receiving more information on the not yet completed Nexium (esomeprazole) study, the FDA has received analyses from 14 other studies on Prilosec (omeprazole). Four of these other studies were placebo controlled trials. These additional studies showed fewer heart related events in the drug groups compared to the placebo groups.
The FDA said there is a lot of data to go through, and it is proving difficult to conduct a thorough review in a short time, hence the announcement of these preliminary findings. The agency said it will complete the full review and give a final decision and recommend any changes to drug usage within the next three months.
In the meantime the agency advises health professionals and patients not to change their medication practices regarding either of the two drugs.
One of the reasons the agency gave for the difficulty it was experiencing in reviewing the data was that “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.”
Another reason was that many of the patients who were in the surgery group in one of the trials pulled out of the study without undergoing surgery. They were on the younger side and less likely to have a history of cardiovascular events or risks compared to the drug group. These group differences could have biassed the results.
The official statement from the FDA regarding its current view on these results is:
“Based on everything we know now, 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.”