One-Year SPIRIT IV Results Support Xience V and Promus DES

September 23, 2009—Abbott Vascular (Santa Clara, CA) announced that Gregg W. Stone, MD, presented 1-year results from the SPIRIT IV trial at the Transcatheter Cardiovascular Therapeutics (TCT) 2009 scientific symposium in San Francisco. The SPIRIT IV data show that the Xience V achieved superiority in the key safety and efficacy measures of target lesion failure (TLF) and target lesion revascularization (TLR) compared to the Taxus Express2 paclitaxel-eluting coronary stent system (Boston Scientific Corporation, Natick, MA) at 1 year. The SPIRIT IV trial is one of the largest randomized clinical trials between two drug-eluting stents, with 3,690 patients enrolled, including more than 1,000 patients with diabetes, the company stated.

Boston Scientific announced that the company welcomed the 1-year data from the SPIRIT IV clinical trial, which support the benefits of paclitaxel-eluting stents in diabetic patients. Boston Scientific markets the Promus everolimus-eluting coronary stent system, a private-label version of Xience V, designed and manufactured by Abbott and supplied to Boston Scientific as part of a distribution agreement between the two companies.

Boston Scientific also announced that on October 1, the company will begin its previously planned phased discontinuation of the Taxus Express2 stent used in the SPIRIT IV trial. The Express stent has been replaced in the company's product line by the thinner-strut Taxus Liberté stent worldwide. The Liberté stent was approved in Europe in 2005, in the United States in 2008, and in Japan in 2009.

• A 38% reduction in TLF (4.2% vs 6.8%; P = .001).
• A 39% reduction in major adverse cardiac events (MACE) (4.2% vs 6.9%; P = .0009). MACE is defined as cardiac death, myocardial infarction (MI), or ischemic-driven TLR.
• A 46% reduction in TLR (2.5% vs 4.6%; P = .001).
• A 31% reduction in cardiac death or target vessel MI (2.2% vs 3.2%; P = .09).
• A 38% reduction in heart MI attributed to the target vessel (1.8% vs 2.9% P = .04).
• Comparable rates in cardiac death (0.4% vs 0.4%; P = 1).
• An observed 80% reduction in stent thrombosis per protocol definition (0.17% vs 0.85%; P = .004).
• An observed 74% reduction in stent thrombosis per Academic Research Consortium definition of definite/probable stent thrombosis (0.29% vs 1.1%; P = .004).
• An observed 80% reduction in stent thrombosis per protocol definition (0.17% vs 0.85%; P = .004).

The SPIRIT IV trial included multiple complex patient subgroups, including more than 1,100 patients with diabetes, who are typically sicker and have more challenging artery disease. In patients with diabetes, there was no difference in TLF between Xience V (and Promus) and Taxus Express2 at 1 year (6.4% vs 6.9%; P = .8). In patients without diabetes, Xience V demonstrated a 54% reduction in TLF compared to Taxus Express2 at 1 year (3.1% vs 6.7%; P < .0001). In the endpoint of Academic Research Consortium definite/probable stent thrombosis, Xience V demonstrated a 40% reduction compared to Taxus Express2 in patients with diabetes (0.8% vs 1.33%; P = .52) and a 94% reduction compared to Taxus Express2 in patients without diabetes (0.06% vs 1%; P = .0009).

In addition, Xience V (and Promus) demonstrated low event rates at 1 year compared to Taxus Express2 in multiple subgroup analyses, such as patients with smaller vessels (reference vessel diameter ≤ 2.75 mm), patients with longer lesions (> 13.3 mm), and patients with multivessel disease. In patients with smaller vessels, Xience V demonstrated a 43% reduction in TLF (3.9% vs 6.8%). In patients with longer lesions, Xience V demonstrated a 35% reduction in TLF (4.5% vs 6.9%). In patients with two or more lesions treated, Xience V demonstrated a 49% reduction in TLF (5.1% vs 10%).