Long-Term SPIRIT III Safety Results Presented at TCT

September 21, 2009—Abbott Vascular (Santa Clara, CA) announced that long-term data from the SPIRIT III pivotal clinical trial in the United States demonstrated that the observed clinical advantages of Abbott's Xience V everolimus-eluting coronary stent system continued to increase as compared to the Taxus Express2 paclitaxel-eluting coronary stent system (Boston Scientific Corporation, Natick, MA). Principal investigator Gregg W. Stone, MD, presented the 3-year results from the SPIRIT III trial at the Transcatheter Cardiovascular Therapeutics (TCT) 2009 scientific symposium in San Francisco. Abbott Vascular supplies a private-label version of Xience V to Boston Scientific, which markets it as the Promus everolimus-eluting coronary stent system.

SPIRIT III is a prospective, multicenter, randomized, single-blind, controlled clinical trial comparing Xience V to Taxus Express2 in 1,002 patients (669 Xience V patients, 333 Taxus Express2 patients) with either one or two de novo coronary artery lesions. The trial was conducted across 65 academic and community-based centers in the United States between June 22, 2005, and March 15, 2006. The primary endpoint of the SPIRIT III trial was in-segment late loss at 8 months, wherein Xience V demonstrated superiority to Taxus Express2 with a statistically superior 50% reduction in late loss (mean, 0.14 mm vs 0.28 mm; P = .004).

• A 43% reduction in the risk of MACE (9.1% vs 15.7%; P = .003).
• A 43% reduction in the risk of target lesion failure (8.3% vs 14.4%; P = .005), which is defined as cardiac death, target vessel myocardial infarction (MI), and target lesion revascularization (TLR).
• A 30% reduction in the risk of target vessel failure (13.5% vs 19.2%; P = .03), which is defined as cardiac death, MI, or ischemia-driven target vessel revascularization.
• A 42% reduction in the risk of MI (3.7% vs 6.3%; P = .07).
• A 39% reduction in the risk of ischemia-driven TLR (5.4% vs 8.9%; P = .05).
• Per protocol definition, a lower rate of very late stent thrombosis (0.2% vs 1%; P = .1). Per Academic Research Consortium definition of definite/probable stent thrombosis, a lower rate of very late stent thrombosis (0.3% vs 1%; P = .34).

In addition to the 3-year results for the overall study presentation, subgroup analyses from the SPIRIT III trial demonstrated evidence of the strong performance by Xience V in a variety of patients and lesion types that represent complex patients. In patients with diabetes, the analysis showed there was no difference at 3 years in major adverse cardiac events (MACE) between Xience V and Taxus Express2 (11% vs 10.3%). Xience V maintained a consistent rate of clinical events after the first year (8.7% MACE at 1 year; 11% MACE at 3 years), whereas Taxus Express2 demonstrated a sustained upward trend in clinical events (4.7% MACE at 1 year; 10.3% MACE at 3 years). In patients without diabetes, the MACE rate for Taxus Express2 at 3 years (18.7%) was more than double the MACE rate for Xience V at 3 years (9.1%).

Boston Scientific announced that it welcomed the 3-year results from the SPIRIT III clinical trial, which the company said continue to reaffirm the long-term safety of the company's drug-eluting stents, including the first-generation Taxus Express paclitaxel-eluting coronary stent system and the Promus everolimus-eluting coronary stent system.

On September 14, Abbott announced that the Chinese State Food and Drug Administration approved the Xience V everolimus-eluting coronary stent system for the treatment of coronary artery disease, which is the leading cause of death in China. The company plans a fourth-quarter 2009 launch for Xience V in China.