ATLANTA (Reuters) - The Novartis diabetes drug Starlix failed to reduce progression to the disease or cut down on serious heart problems in patients at high risk for both diabetes and heart disease, according to a large study released on Sunday.

The 9,306-patient study tested Starlix, known chemically as nateglinide, and the big-selling Novartis blood pressure medicine Diovan.

Diovan, known chemically as valsartan, reduced progression to diabetes by 14 percent compared to a placebo but failed to reduce the risk of serious heart problems, such as heart attack and stroke, according to researchers who presented the data at the American College of Cardiology scientific meeting in Atlanta.

The failure of Starlix to provide benefit to these patients and lack of heart impact by Diovan came as a surprise to researchers.

“Most experts believed that nateglinide would prevent diabetes and that valsartan would reduce cardiovascular events in this population,” said Dr. Robert Califf, the study’s lead investigator.

“Interestingly, with respect to nateglinide, we found the opposite,” Cardiff said.

Starlix works by minimizing spikes in blood sugar after meals by stimulating the pancreas to produce more insulin, leading researchers to believe it might slow progression to diabetes by restoring a more normal insulin response.

In addition to the drugs or placebo, all patients in the Novartis-sponsored study were required to take part in a lifestyle program with a goal of maintaining a 5 percent weight loss, increasing physical activity to an average of 30 minutes five days a week, and follow a low-fat diet.

Patients were followed for an average of five years for development of diabetes and 6.5 years for heart disease.

Impact on heart risk was measured by a combination of death from cardiovascular causes, nonfatal heart attacks, nonfatal stroke, hospitalization for heart failure, unstable chest pain and the need for artery-clearing procedures.

Researchers speculated that the negative results seen with the two drugs may have been related to success of the diet and exercise program in reducing progression to diabetes and heart risk.

They also said other medicines many patients were taking, such as cholesterol-lowering drugs, may have lowered the overall risk.

Analysts did not believe the study would materially impact Diovan sales as the drug is set to go off patent in 2012.