Newspaper Suggests Flaws in Study of Boston Scientific Stent

A Boston Scientific Corp. heart stent awaiting US approval is backed by flawed research despite the medical device maker’s claims of success in a clinical study, the Wall Street Journal alleges, citing the newspaper’s own review of the study data.

The 2006 study of the device, already sold overseas under the brand name Taxus Liberte, is currently being reviewed by the US Food and Drug Administration.

“Boston Scientific’s claim was based on a flawed statistical equation that favored the Liberte stent,” the newspaper said, noting the equation is known as the Wald interval.

Using a number of other methods of calculation — including 14 available in off-the-shelf software programs — the Liberte study would have been a failure by the common standards of statistical significance in research, the Journal said.

The journal said rival stent makers, including Medtronic Inc. and Abbott Laboratories also use the equation, which the newspaper said has long been criticized by statisticians for exaggerating the certainty of research results.

But any boost provided by the Wald equation would not have changed the outcome of studies involving Medtronic and Abbott stents, the Journal said.

In the Taxus Liberte study, the equation’s shortcomings meant the difference between success and failure of the trial’s main goal, the newspaper said.

Boston Scientific spokesman Paul Donovan, asked by Reuters to comment on the Journal article, said it poses “an interesting statistical debate, but has no bearing on the performance of Taxus Liberte.”

Donovan said the company remains hopeful the United States will approve the new stent in the third quarter. He said Taxus Liberte is designed to be more flexible and more deliverable than the company’s older Taxus Express 2 stent, which is widely used in the United States and overseas.