SYNTAX clinical trial results announced

Sep 3 2009

Boston Scientific Corporation (NYSE: BSX) today announced two-year data from its SYNTAX clinical trial comparing percutaneous coronary intervention (PCI) using the TAXUS((R)) Express((R)) Paclitaxel-Eluting Coronary Stent System to coronary artery bypass graft (CABG) surgery. The overall results demonstrated no statistically significant difference between PCI and CABG in the composite safety endpoint (all-cause death, stroke and myocardial infarction [MI]). The Company made the announcement at the annual European Society of Cardiology (ESC) Congress in Barcelona.

"These results reinforce the one-year SYNTAX data and show impressive outcomes for PCI in patients with complex coronary anatomy, the majority of whom are normally treated with CABG surgery," said Keith D. Dawkins, M.D., Associate Chief Medical Officer of Boston Scientific. "Today's findings build on our prior data and provide additional support for PCI as a viable treatment option for many of these challenging patients."

The patients in the SYNTAX trial - all of whom have left main and/or three-vessel coronary disease - are a unique study group in the PCI field. In the SYNTAX trial, mean stent use was 4.6 stents/patient, with one patient having 14 stents implanted. By contrast, the average number of stents implanted in a PCI patient in everyday practice is 1.5. In addition, the study included 33 percent of patients with >100 mm stented length, 71 percent with bi/trifurcations, 27 percent with chronic total occlusions and 39 percent with left main disease.

The results showed comparable safety profiles for the two treatment groups at two years, with a combined rate of all-cause death, stroke and MI of 10.8 percent for PCI and 9.6 percent for CABG>

Overall MACCE (Major Adverse Cardiovascular or Cerebrovascular Event rate, including all-cause death, stroke, MI and repeat revascularization) was significantly higher for PCI (23.3 percent as compared to 16.4 percent for CABG,>

The trial results were also analyzed based on the SYNTAX Score, which demonstrated no statistically significant difference in MACCE for patients in the lower two terciles - those with low lesion complexity (19.4 percent for PCI and 17.4 percent for CABG,>

The SYNTAX Score is a novel angiographic tool used to measure the complexity of coronary artery disease based on nine anatomic criteria, including lesion frequency, complexity and location. Higher SYNTAX Scores indicate patients with more complex disease and increased treatment challenges. A SYNTAX Score website, www.syntaxscore.com, was launched in May and allows cardiologists and cardiac surgeons to characterize a patient's anatomical complexity, which can be used in combination with a physician's clinical judgment to help determine the best revascularization option.

The SYNTAX Score and SYNTAX Score website were developed under the direction of the SYNTAX trial steering committee, chaired by Patrick Serruys, M.D., Ph.D and F.W. Mohr, M.D., Ph.D., and were made possible by support from Boston Scientific and Cardialysis BV.

The safety and effectiveness of the TAXUS Express Stent System has not been established in patients with left main or three-vessel disease.