Boston Scientific’s Study at Heart Meeting Under Review

Boston Scientific Corp.’s study of a heart device to reduce stroke risk, slated for presentation at a medical heart meeting this weekend, is under review after the company said only limited data about the product’s safety would be released.

The company said it planned to present the results of the “acute procedural safety” at the American College of Cardiology meeting this weekend in San Francisco. The device is used to seal off a reservoir in the upper chamber of the heart that allows blood to pool and form potentially devastating clots that can trigger strokes. The study was designed to see whether the product, known as the Watchman, could prevent strokes.

“The release yesterday surprised us,” said Beth Casteel, a spokeswoman for the American College of Cardiology. “We are investigating with them how much they will present.”

The results of the study called Prevail were cited as the most-anticipated findings slated for presentation at the three-day meeting by Miguel Quinones, professor at Weill Cornell Medical College in New York, and chairman of the heart conference. More information may be available tomorrow about the plans for the presentation, Casteel said in a telephone interview.

Steve Campanini, a spokesman for Natick, Massachusetts-based Boston Scientific, said the company is still evaluating the efficacy data to see if it will be ready for presentation.

Results Questioned

The limited release may indicate the Watchman device failed to meet one or two of the study’s main goals, those that aren’t being presented, said Larry Biegelsen, an analyst at Wells Fargo in New York. In addition to the device’s safety in the week after it is implanted, the study was designed to look at risks of stroke, clots and unexplained deaths, and the clotting risks more than a week after patients enrolled in the trial.

“We find this highly unusual given that Prevail is one of the featured late-breaking trials at ACC,” Biegelsen wrote in a note to clients. “Given the unusual nature of this development, i.e. only one of three primary endpoints being presented, we would not be surprised to see this decision change by Saturday.”

Quinones didn’t know the company planned to limit the presentation of the study results when he was asked last week to identify the trial that may have the biggest impact on medical care. When pressed, he picked the Boston Scientific-funded study.

‘Innovative Treatment’

“If we matched the fact that it’s an innovative treatment, a new form of treatment, with a disease that is extremely common, with findings that can be catastrophic, i.e., having a stroke or bleeding in your brain, if you put it all together, yes, it would probably be Prevail,” he said during a conference call with reporters. “However, if the findings aren’t that striking, then it’s just one more device that came in and went out.”

The ACC meeting and the presentation of the Prevail data will be the first major event for Michael Mahoney, who took the helm in November as Boston Scientific’s chief executive officer. He said innovative new products and the integration of acquisitions should return company to growth this year, making it the first increase since 2009.

Share Rise

Investors have given Mahoney the benefit of the doubt, sending shares up 41 percent since he took office. Boston Scientific gained less than 1 percent to $7.38 at the close today in New York.

The company had fallen from a high of $45.81 on April 5, 2004, to a low of $4.97 on July 26, 2012.

The Watchman device has had a roller coaster past and projections about the future are unclear. It is already sold in Europe, where it competes with St. Jude Medical Inc.’s Amplatzer Amulet device.

Boston Scientific obtained the technology in 2011 when it acquired closely held Atritech Inc. for $100 million, with another $275 million in potential payments linked to regulatory and sales-based milestones. The Food and Drug Administration had rejected Atritech’s application for Watchman a year earlier, asking for additional information about its safety. Atritech had begun the Prevail trial to evaluate the risks.

The Watchman is used to block off a reservoir that bulges from the left atrium. When the heart beats normally, the reservoir contracts with the rest of the heart and blood is pushed out to fuel the body. For 6 million Americans, however, a rhythm disturbance known as atrial fibrillation impedes the contractions and allows the blood to pool, potentially forming clots that can travel to the brain and cause strokes.

Inverted Umbrella

Boston Scientific’s device is threaded into the bulge and opened like an inverted umbrella, sealing it off. It offers a potential alternative to lifelong drug therapy that thins the blood to prevent clots. While the blood thinners avoid the risk of surgery, they can increase the chance of uncontrolled bleeding. The Prevail trial was designed to see if the risks from inserting the Watchman seen in earlier studies were outweighed by its benefits.

“Atrial fibrillation is the most common arrhythmia seen in adults, causing palpitations and fatigue,” said Ken Stein, chief medical officer for Boston Scientific’s cardiac rhythm management group. “The most feared complication is that it can put people at risk for stroke, and the strokes tend to be particularly devastating.”

Millions Apart

The Prevail trial and the earlier studies compared Watchman with warfarin, a form of rat poison that for decades has been the standard of care for atrial fibrillation. Since the study began, three new pills have reached the market: Pfizer Inc. and Bristol-Myers Squibb Co.’s Eliquis, Bayer AG and Johnson & Johnson’s Xarelto and Boehringer Ingelheim GmbH’s Pradaxa.

“For patients who are able to take these drugs, they really are wonderful,” Stein said in a telephone interview. Still, half of those eligible to take them don’t, and 20 percent of patients in studies quit taking the new drugs within two years.

“What patients need isn’t just a better anticoagulant drug,” he said. “What they need is an alternative for those unwilling and unable to take blood thinners over the long term.”

Just how many people may fall into that category is unclear. Boston Scientific last month projected the market for the closure devices may reach $500 million by 2017. Biegelsen, the Wells Fargo analyst, projects Watchman sales of $159 million by 2017.

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