Lilly sets new prasugrel trial after mixed results

NEW YORK (Reuters) - Eli Lilly and Co and Daiichi Sankyo on Monday announced a new late-stage test of their experimental anti-clot drug prasugrel among patients with heart problems, after a major trial showed mixed results.

The partners, who hope prasugrel will eventually become a strong rival to Bristol-Myers Squibb Co’s $6 billion-a-year Plavix blood clot preventer, said their new study should begin in the second quarter of 2008.

The 10,000-patient trial, called Trilogy ACS, will compare prasugrel to Plavix (clopidogrel) in patients with acute coronary syndromes, a group of conditions that include heart attacks and chest pain caused by clogged coronary arteries.

It will examine prasugrel’s effectiveness in reducing risk of cardiovascular death, heart attack or stroke in patients who are not planning to receive stents, tiny cylindrical devices used to prop open heart arteries that have been cleared of plaque.

Mixed results were announced on Sunday from another Phase III trial that compared prasugrel and Plavix among patients with acute coronary syndromes, but among patients who did receive stents.

In that trial, called Triton, prasugrel was 19 percent more effective in preventing cardiovascular death, nonfatal heart attacks and strokes than Plavix, but caused a 32 percent higher incidence of serious bleeding.

“We expect that the U.S. Food and Drug Administration will want to see the results of (the Trilogy) trial before approving prasugrel,” Natixis Bleichroeder analyst Jon LeCroy said in a research report.

He predicted the planned new trial will not be completed until early 2010 and that prasugrel, therefore, will not be approved until 2011. In the meantime, he said the Lilly drug would remain in “purgatory.”

Other industry analysts on Monday also said the new study would largely determine whether prasugrel is approved or has appreciable sales because most patients treated for acute coronary syndromes do not receive stents.

Instead, they are treated with medicines, such as ones to prevent blood clots that can trigger heart attacks and stroke.

JP Morgan analyst Roberto Cuca, by contrast, said the Triton trial showed prasugrel’s benefits outweigh its risks and he predicted the FDA will likely approve the medicine based upon existing clinical data.

“Commercial uptake may be a greater challenge given the somewhat mixed results” of the Triton study, he cautioned.

Daiichi Sankyo and Lilly are co-developing prasugrel, which works by preventing blood cells called platelets from sticking together to form clots. Daiichi Sankyo and its Japanese research partner, Ube Industries Ltd, invented the drug.

Shares of Lilly edged down 79 cents, or 1.5 percent, to $51.88 at mid-afternoon on the New York Stock Exchange, amid a moderate decline for the drug sector. Shares of Daiichi Sankyo rose 7.42 percent, while Ube Industries rose 9 percent, both in Tokyo.