WCXX

The companies, which jointly sell several diabetes drugs, said on Wednesday the so-called SAVOR trial showed that patients on Onglyza had no fewer adverse cardiovascular events, such as heart attacks and strokes, than those on placebo.

Doctors and investors had been awaiting results of the SAVOR trial with keen interest, since a positive result could have encouraged increased use of the drug.

In the event, the study found Onglyza was no worse than placebo or standard care in terms of cardiovascular outcomes, but it failed to meet the goal of demonstrating superiority.

Heart risks are particularly important in diabetes, since patients with the disease are at increased risk of suffering a heart attack or stroke. Regulators are also stepping up scrutiny of diabetes drugs to make sure they do not add to cardiovascular dangers.

The clinical trial evaluated adult patients with type 2 diabetes with either a history of established cardiovascular disease or multiple risk factors.

Onglyza, which had sales of $709 million in 2012, is a crucial product in a diabetes joint venture established by Britain's second-biggest drugmaker and U.S.-based Bristol, but its sales have recently stalled in the United States.

Analysts at Berenberg Bank said in a note last week that a demonstrable cardiovascular benefit for Onglyza could have reinvigorated demand, leading to eventual peak sales of $3 billion by 2020 - $1 billion more than the broker's base-line forecast.

AstraZeneca and Bristol gave only the headline results from the SAVOR clinical study, since detailed findings have been submitted to the European Society of Cardiology (ESC) for potential presentation at the ESC Congress in September.

Onglyza belongs to a class of medicines known as dipeptidyl peptidase-4 (DPP-4) inhibitors, which also includes Merck & Co's Januvia, the market leader. Eli Lilly and Boehringer Ingelheim also market a DPP-4 called Tradjenta.

(Editing by Rosalba O'Brien and Jane Merriman)