| March 20
March 20 A clinical trial evaluating St. Jude
Medical Inc's implantable device used to prevent stroke
in patients who have a common congenital heart defect failed to
achieve its main goal.
St. Jude, which paid for the 980-patient study, said it used
the trial data to file for U.S. regulatory approval and
submitted an application to the U.S. Food and Drug
Administration in the fourth quarter of 2012.
The device, a permanent implant, is used on people who have
a hole in the wall that separates the left and right upper
chambers, of the heart. Everyone has a hole present at birth,
but it never closes in about one-quarter of the population,
according to the National Institutes of Health.
The hole - called a patent foramen ovale, or PFO as it is
more commonly known - raises the risk of stroke. It usually is
not treated unless a blood clot causes a stroke, or if there are
other heart problems. When relatively young people have a stroke
without an identifiable cause, a PFO is often suspected.
Dr. Jeffrey Saver, director of the UCLA Stroke Center and
one of the lead investigators of the study, dubbed RESPECT, said
the trial demonstrated that implanting the device in the heart
is likely a better strategy for reducing stroke than just using
anti-clotting medication, such as aspirin or Warfarin.
"It's not formally a positive trial; it missed the primary
endpoint," Saver said in a telephone interview.
Results of the trial were published in the New England
Journal of Medicine.
The study showed a 51 percent reduction in stroke in the
group of patients who got the device versus those who were
treated with drugs.
The goal of the study had been to detect a 75 percent
reduction in stroke, he said.
"That was an over optimistic goal to reach for," he added.
There is still evidence of superiority, and so some doctors
might use the PFO closure device because it allows patients to
rely less on anti-clotting drugs, which carry a risk of
Saver said doctors estimate that medication alone cuts the
risk of stroke by 20 percent to 60 percent in patients who have
PFO. The risk is only an estimate because it never has been
studied for ethical reasons.
In a prepared statement, St. Jude said the Respect study
provides "compelling evidence" that its device, called AMPLATZER
PFO Occluder, is superior to drugs.
"The totality of evidence from this study, including the
strong performance and safety profile of the device,
demonstrates the compelling clinical benefits of closure versus
medical management in reducing the likelihood of recurrent
stroke in this patient population," Frank Callaghan, president
of the St. Jude Medical Cardiovascular and Ablation Technologies
Division, said in an emailed statement.
The device won European regulatory approval in 1998. It is
available in more than 60 countries outside the United States,
including Canada, Latin America, Europe, Australia, Asia and the