
An FDA panel recommended that the agency’s Center for Devices & Radiological Health re-analyze existing data for St. Jude Medical‘s (NYSE:STJ) Amplatzer heart implant during a hearing yesterday to review safety data for the Amplatzer and for W.L. Gore & Associates‘ Helex implant.
The watchdog agency’s circulatory devices committee reviewed safety data for the devices, which are septal occluders designed to close holes in the septum between the upper chambers of the heart.
The Amplatzer device, which St. Jude acquired along with AGA Medical for $1.03 billion in 2010, was the 1st such device on the U.S. market, winning pre-market approval in 2001. Gore’s Helex followed in 2006.
The panel focused primarily on a pair of rare but serious adverse events that have become more apparent with growing use: Erosion of cardiac structures with STJ’s Amplatzer and device fracture with Gore’s Helex.
Erosion of cardiac structures with the Amplatzer occured less than 0.1% of the time and has been observed to occur most frequently within the 1st year of implantation, with 2 of 3 patients with cardiac perforation due to device erosion presenting within the first 3 days, according to St. Jude. But panelists cautioned that there’s not enough post-market information available yet to say exactly what causes either erosion or fracture.
Although the panel wants more tracking of the Amplatzer device, chairman Dr. Clyde Yancey acknowledged St. Jude’s effort to examine post-surveillance data from the device "every which way and sideways."
"Nonetheless, we think there should be some re-assessment in terms of doing re-analysis of the data, with 2 points in mind," Yancey said. "The first is going back to the drawing board and having a broader view, not focusing so carefully on the anatomy, which would seem to be the most likely explanation, but to consider other factors in this re-analysis."
Though there was no move toward modifying the post-approval studies for either device, the panelists asked the FDA to consider a prospective, case-controlled study of the Amplatzer device.
Any post-market surveillance, or 522 registry study, "should augment the current prospective postmarketing studies that are ongoing, and secondly it should have multiple outcomes," Yancey said. "So, it would not be erosion only that would not be an efficient use of that design, it should [also] have embolization and fracture."
But panelists did’t express any enthusiasm for a new registry, countering suggestions from cardiac professional societies.
For its part, St. Jude said it’s confident in its post-market monitoring of the devices.
"As the leader in the transcatheter closure market, we are confident in the performance of our Amplatzer septal occluder, which has demonstrated successful outcomes in the ASO pivotal trial and through more than 12 years of commercial experience with nearly 225,000 devices sold worldwide," a St. Jude spokeswoman told MassDevice.com in an email. "As we stated at the FDA panel meeting yesterday, we are committed to providing continuous guidance to our physicians to prevent potential adverse events and ensure the safety of their patients. We respect the role of the FDA in protecting patient safety and will continue to work closely with the agency to best ensure physicians have the necessary data to optimally care for patients."
Representatives from W.L. Gore did not immediately respond to a request for comment.
Circulatory committee members noted a lack of data to precisely identify which patient subgroup is at increased risk for some events associated with atrial septal defect closure, though they were able to identify characteristics related to the size of the occluder.
And ASD devices increase the risk and difficulty of performing possible future interventions, the panel agreed.
While panelists acknowledged that ther’s not enough data to pinpoint the causes of either erosion with the Amplatzer device or fracture related to the Helex, they said post-market surveillance by both St. Jude and W.L. Gore seems sufficient to provide answers down the line.
Panelists further recommended "fairly intense" patient follow-up in the first year, including multiple echocardiograms. Beyond the first year, panelists recommended clinical follow-up only, on an annual or a biannual basis. A precise tracking system is also needed, according to the panel, in order to make it clear who’s receiving the devices.
Direct communication with already-implanted patients is also a must, but should be "very carefully constructed so as not to elicit undue panic for a very low-frequency event," Yancey said. "It should be very clear what kinds of warning signs should be heeded, what kind of follow-up should be implemented."
"Our goal is to communicate clearly to patients what we know," an FDA spokesman told the panel. "That can occur either via separate communiqués from each company or based on post-panel discussion with both sponsors and the FDA.
"Perhaps there is a joint statement that can describe this panel meeting and other relevant information. While there are limitations right now to identification of all patients who have this device and all implanting physicians, again FDA and the 2 sponsors will work diligently to try to reach as many relevant people as possible."