Boston Scientific halts reflux treatment

After more than two dozen reports of problems with a treatment for acid reflux, Boston Scientific Corp. has suspended sales of its Enteryx injection kit, saying it considers the product safe but that some patients had been harmed because doctors used it incorrectly.

About 3,800 patients have been treated with Enteryx, which was approved in 2003 by the Food and Drug Administration. It is a liquid polymer injected directly into the walls of the esophagus, the tube that leads from the mouth to the stomach. The product thickens into a permanent spongy lump and is supposed to help block acid from flowing from the stomach toward the throat.

Boston Scientific's recall notice, posted on its website last week, said some doctors accidentally punctured the wall of the esophagus while injecting the substance, causing ''adverse events."

According to reports filed with the FDA, patients have suffered leakage, painful swelling, and ulcers in the esophagus.

Last year, an elderly patient died after a doctor accidentally hit the wall of the patient's aorta, the body's largest artery. The company issued a safety alert in July 2004.

The withdrawal marks an abrupt end for what the Natick medical device maker touted in 2004 as one of its most promising new products. The disease it treats, gastroesophageal reflux disease, is common, affecting about 7 percent of the population. Analysts initially projected Enteryx could generate several hundred million dollars a year in revenue, but the procedure has been dogged by problems with patient safety and questions about whether insurers would reimburse for the injection.

''That basically was touted as a potential $500 million product, and it's turned out to be a zero," said Mark Landy, a medical-device analyst for Susquehanna International Group.

Boston Scientific sold about $5.5 million worth of Enteryx kits last year.

Dr. Ram Chuttani, chief of endoscopy at Beth Israel Deaconess Medical Center, says his hospital has performed 40 to 50 Enteryx procedures but began limiting it to only serious acid-reflux sufferers after last year's safety alert. He said the hospital had not encountered serious problems, although one patient was admitted for treatment after the procedure.

''Technically it is very demanding," Chuttani said. ''It is quite difficult to control even in the best settings -- even in experienced hands, when you inject, you cannot be absolutely certain where the Enteryx is injected."

The company called Chuttani and other doctors to tell them to stop using the kits. The website notice also directed patients who have received Enteryx injections within the last month to see their doctors.

''It sounds like they saw a safety issue developing and the took it off. I would almost applaud them for that," said Jan Wald, an analyst for A. G. Edwards & Sons, Inc.

The FDA began a review of Enteryx last year after several reports of complications with the procedure. A Boston Scientific spokesman yesterday said he did not know if the review was still underway. An FDA spokeswoman could not confirm the status of the review.

Stephen Heuser can be reached at sheuser@globe.com.