Recall of Boston Scientific ENTERYX Injector Packs

Recall of Boston Scientific ENTERYX® Injector Single Packs for Treatment of
Gastroesophageal Reflux Disease (GERD)

October 14, 2005

There are serious adverse events, including death, occurring in
patients treated with Boston Scientific’s ENTERYX® for gastroesophageal reflux disease
(GERD), and to provide recommendations on avoiding future occurrences.

On September 23, 2005, Boston Scientific Corporation issued a recall of ALL
ENTERYX® Procedure Kits and ENTERYX® Injector Single Packs from commercial
distribution. Physicians should stop injecting ENTERYX® immediately and follow the
manufacturer’s procedures for returning unused product.

Nature of the Problem
ENTERYX® is a liquid chemical polymer which is intended to be injected into the lower
esophageal sphincter. The device polymerizes into a spongy material shortly after
injection and once injected cannot be removed.

The serious adverse events involve unrecognized transmural injections of ENTERYX®
into structures surrounding the esophagus. Transmural injections can potentially result in
death or serious injury. Signs and symptoms of transmural injection can potentially
include: chest pain, flu-like symptoms, pneumonia, atelectasis, reactive pneumonitis,
mediastinitis, pneumo-mediastinum, reactive pleuritis, pleural effusion, pericardial
effusion, syncopal episodes, and flank pain. Some cases of transmural injection were not
recognized at the time of the procedure or during immediate follow-up; these occurred
even though fluoroscopy was used throughout the procedure. Three weeks was the
longest period that we know of in which a transmural injection went unrecognized by a
physician.

At this time, it is not possible to provide accurate estimates of the number of adverse
events associated with transmural injection of ENTERYX®, or to describe all of the
possible outcomes. Reports received thus far suggest ENTERYX® has been injected into
various sites outside the esophagus including the mediastinum, pleural space and the
aorta. When injected into the aorta, ENTERYX® may migrate to and occlude blood
vessels which supply other organs including the kidneys. One reported death was due to
injection of the ENTERYX® into the wall of the aorta, which resulted in an aorto-enteric
fistula. Another patient experienced a partial reduction in renal function due to partial
embolization. It is not known at this point whether ENTERYX® injected outside the
esophagus can be removed.

FDA is aware that not all injuries are caused by user technique or transmural injection.
Recent literature cites 2 cases in which serious mediastinal events suggestive of possible
inflammatory reactions occurred even though proper procedure was followed. Other
adverse events not associated with transmural injection have also been reported to the
FDA, some of them presenting 4 to 7 weeks after ENTERYX® injection. They include
dysphagia from esophageal stenosis or stricture that required dilation procedures, and
weight loss. These later-onset events appear to be different from the immediate onset,
short-lived events observed during the approval trial for ENTERYX®.

Recommendations
Physicians are advised to immediately stop using ENTERYX®.
If transmural injection of ENTERYX® has occurred or is suspected at the time of
implantation, the patient should be monitored carefully for at least 30 days.
For all patients who have received ENTERYX®, we recommend that you:
1. advise your patients to seek medical evaluation immediately if they experience
the onset of symptoms which may indicate transmural injection. These include
chest or epigastric pain, flu-like or respiratory symptoms (fever, cough, shortness
of breath), syncope or flank pain. You may wish to provide them with a copy of
FDA’s "Advice for Patients with ENTERYX® for Gastroesphageal Reflux
Disease," available at
http://www.fda.gov/cdrh/medicaldevicesafety/atp/101405-enteryx.html.
2. perform tests, as clinically indicated, including chest x-rays, barium swallows,
and/or chest/abdominal CT scans to confirm or rule out transmural injection.
3. advise patients to:
• continue with their regularly-scheduled follow-up appointments; and
• go immediately to an emergency room if they experience chest pain or
syncope.
Since physicians should no longer be implanting ENTERYX®, the FDA is not making
recommendations about techniques in using the product.

Reporting Adverse Events to FDA
FDA requires hospitals and other user facilities to report deaths and serious injuries
associated with the use of medical devices. If you suspect that a reportable adverse event
was related to the use of ENTERYX®, you should follow the reporting procedure
established by your facility. Prompt reporting of adverse events can improve FDA’s
understanding of and ability to communicate the risks associated with devices and assist
in the identification of potential future problems.

We also encourage you to report adverse events related to ENTERYX® that do not meet
the requirements for mandatory reporting. You can report these directly to the device
manufacturer. You can also report to MedWatch, the FDA’s voluntary reporting program.
You may submit reports to MedWatch by phone at 1-800-FDA-1088; by FAX at 1-800-
FDA-0178; by mail to MedWatch, Food and Drug Administration, 5600 Fishers Lane,
Rockville, MD 20857-9787; or online at http://www.fda.gov/medwatch/report.htm.
Consumers can also report directly to MedWatch.

Getting More Information
For more information about the recall, contact Boston Scientific Corporation at 1-800-
862-1284. For more information on litigation, contact Bagolie Friedman at 1-866-333-3529 or visit http://www.bagoliefriedman.com