Medtronic Inc.'s drug-coated heart stent Endeavor had more deaths and complications than Johnson & Johnson's rival device to prop open clogged arteries, research funded by both companies found.
After 18 months, Medtronic's Endeavor stent was tied to heart attacks, deaths and repeat surgeries in 9.7 percent of patients, compared with 4.5 percent for J&J's Cypher, according to a study presented Monday at the American College of Cardiology meeting in Atlanta and published online by the journal Lancet.
Results confirm findings from similar nine-month data reported in 2008 that found Cypher safer, said Micheal Maeng, lead researcher of the recent 2,332-patient study.
The new findings may cut Medtronic's share of the $4 billion global market for drug-coated stents to 18 percent, from 20 percent, said Jan Wald, an analyst with Noble Financial Group in Boston.
"If you have to compare the two stents, the Cypher stent is a better stent," said Maeng, the study's lead researcher and a cardiologist at Aarhus University Hospital in Denmark, in a statement. He has received payments from both Medtronic and J&J.
The design of the study "raises questions about the reproducibility, viability and applicability of the results," Medtronic said in a statement.
The Fridley-based device maker faulted the study's reliance on data from a Danish patient registry rather than direct physician follow-up of patients, and the method by which investigators collected data on certain complication rates.
Jeffrey Leebaw, a spokesman for New Brunswick, N.J.-based J&J, had no immediate comment on Medtronic's statement. Maeng didn't return calls seeking comment.
