NATICK, Mass., Dec. 4, 2012 /PRNewswire/ -- The first patient has been enrolled in a Boston Scientific Corporation (NYSE: BSX) study comparing the WallFlex® Biliary RX Fully Covered self-expanding metal stent (SEMS) to plastic stents for the treatment of benign bile duct strictures caused by chronic pancreatitis. This multi-center, prospective, randomized study will enroll 164 patients at leading hospitals in Australia, Austria, Belgium, Canada, France, Germany, Hong Kong, India, Italy and the Netherlands. In a separate single-arm study, 187 patients were treated with the WallFlex Stent for multiple types of benign biliary strictures including, those caused by chronic pancreatitis. The stents implanted in that study were removed up to one year after being placed in the body. Five-year follow-up post stent removal is ongoing. Preliminary data were presented this summer at Digestive Disease Week 2012 by Professor Jacques Deviere of Erasme Hospital in Brussels. The data indicate that a SEMS can be removed safely any time up to one year post placement, and that short-term stricture resolution rates compare favorably with the results reported with plastic stents in chronic pancreatitis-related benign biliary strictures. "Preliminary data show promising results for the treatment of chronic pancreatitis-related benign biliary strictures using SEMS, compared to literature on the use of plastic stenting," said Professor Puspok of the Medical University of Vienna, an investigator in both studies who enrolled the first patient in the randomized study. "Multiple plastic stenting remains an established treatment choice for biliary strictures caused by chronic pancreatitis. However, this form of treatment requires multiple stent exchanges and the long-term success rate is low. Treatment with removable fully covered SEMS could overcome these limitations. A head-to-head comparison of both stenting treatment regimens is essential in order to collect robust data to guide physicians in the optimal treatment of their patients with chronic pancreatitis." SEMS, which have a significantly larger diameter than plastic biliary stents, have long been the standard of care for palliation of malignant biliary strictures. The studies above are evaluating the benefits of using a SEMS in benign biliary strictures, with an objective to demonstrate stricture resolution in fewer procedures.