FDA to thoroughly analyze safety of AstraZeneca's heartburn drugs

Two widely popular heartburn drugs Prilosec and Nexium taken by tens of millions around the world to treat their stomach ulcers may raise the risk of heart attacks, if taken for many years, according to two small studies conducted by AstraZeneca, the British maker of the two drugs.

But, after a preliminary analysis of the two AstraZeneca studies, the US Food and Drug Administration and Health Canada on Thursday said the popular acid reflux drugs Nexium and Prilosec do not cause heart problems. They also said doctors prescribing these two medicines for acid reflux and ulcers should continue.

Although, the findings from the study of Prilosec and analyses from an ongoing study of Nexium raised concerns that long-term use of two drugs may have increased the risk of potential heart attacks and heart-related sudden death in those patients taking either one of the drugs compared to patients who underwent surgery, but the US health agency said the AstraZeneca treatments could not be held responsible for the increased risk.

On May, 29, AstraZeneca provided FDA the preliminary review of data from two long-term studies comparing the drugs' effectiveness to surgery.

The US health watchdog and its Canadian counterpart then began reviewing the studies that compared treating the chronic heartburn known as gastroesophageal reflux disease (GERD) with either of the two drugs or with surgery. After tracking the patients for five to 14 years, the studies suggested the possibility of a risk.

After a follow up on those studies, the regulators found that Patients who received surgery were younger and healthier than those treated by drugs, suggesting the heart link was a coincidence.

To reach their preliminary assessment, the regulators went through 14 additional studies of the drugs and found no evidence of heart risks, instead, in a few studies, the heartburn drugs showed lower incidence of heart problems compared to placebo medication.

The preliminary U.S. and Canadian probes, though, indicate that the drugs don't prompt the risk for heart attack or other heart problems, but the regulators say they need three more months to complete a thorough analysis of the drugs’ safety.

The FDA yesterday issued a public notice, saying that it "does not believe that health care providers or patients should change either their prescribing practices or their use of these products at this time."

Prilosec, which has been around since 1989, and Nexium, launched in 2001, are nearly identical and are part of a class of medicines known as proton pump inhibitors that resolve heartburn by reducing the stomach’s production of acid.

Nexium is the world's No. 2 selling drug after the cholesterol-lowering drug Lipitor, with last year sales of $6.7 billion. Prilosec, which is also sold over the counter to treat frequent heartburn, posted sales of $1.4 million in 2006.

AstraZeneca shares dipped $1.74, or 3.4 percent, Thursday to $49.30 in midday trading.