* Onglyza fails to show cardiovascular benefit in study
* Positive results might have added $1 bln to peak sales
* Drug achieves non-inferiority goal versus placebo
LONDON, June 19 (Reuters) - AstraZeneca and Bristol-Myers Squibb's diabetes drug Onglyza failed to reduce heart risks in a large clinical study, disappointing investors who had thought it might demonstrate an edge over rivals.
The companies, which jointly sell several diabetes drugs, said on Wednesday the 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 and others from its class, which also includes Merck & Co's Januvia, the market leader.
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 or other health risks.
"We see this news as removing a potential positive catalyst that could have reinvigorated growth for the class as a whole," JP Morgan analyst Chris Schott said in a research note.
ISI Group analyst Mark Schoenebaum said he does not expect the non-inferiority finding to alter physician prescribing habits.
A similar heart study of Merck's Januvia in more than 14,000 patients, called TECOS, is being conducted with results expected next year. Januvia and the related combination treatment Janumet have combined annual sales of about $5 billion, but sales unexpectedly declined in the first quarter.
"If TECOS were to somehow show superiority on cardiovascular safety it would be a differentiated win for the company," Sanford Bernstein analyst Tim Anderson said in a research note.
The Onglyza clinical trial evaluated more than 16,000 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-Myers, 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. Eli Lilly and Boehringer Ingelheim also market a DPP-4 called Tradjenta.