May 8, 2009 - Preliminary data presented yesterday at the 32nd annual SCAI Scientific Sessions show that 82 percent of patients treated with Cook Medical’s Zilver PTX drug-eluting peripheral stent were free from reintervention at two-year follow up.
The ongoing Zilver PTX Registry study, involving 792 patients from across the world, is assessing the safety and efficacy of the Zilver PTX in treating PAD.
In many cases, PAD patients who have been treated with balloon angioplasty and stenting experience restenosis, or renarrowing of the arteries, over time and must undergo more invasive treatment such as bypass surgery to restore blood flow to key arteries. The Zilver PTX self-expanding nitinol stent uses a proprietary, polymer-free technology to coat the device with paclitaxel, an antiproliferative drug that has been used successfully to reduce the risk of renarrowing of arteries following angioplasty in coronary disease patients.
“These results are extremely encouraging as it’s the first time paclitaxel-coated stents have been used in the treatment of blockages in arteries outside the heart,” said Michael Dake, M.D., medical director of the cath/angio laboratories at Stanford University Medical Center and the Zilver PTX global principal investigator. “Patients treated with the Zilver PTX have thus far had a very low complication rate and require fewer reinterventions.”
Data from the registry arm of the study, which enrolled a broad spectrum of patients including those with complex lesions (e.g., long and complex lesions, occlusions, in-stent restenosis), were compiled at 12 and 24 months for 593 patients and 177 patients, respectively. The corresponding event-free survival (EFS) rates were 87 percent and 78 percent, and freedom from TLR (target lesion revascularization) was 89 percent and 82 percent. Clinical measures that included ankle-brachial index, Rutherford score, walking distance and speed scores showed significant improvement at six and 12 months and were maintained through 24 months.
Detailed evaluation of stent X-rays demonstrated excellent stent integrity through 12 months, confirming previously published results showing 99 percent completely intact stents with a mean follow up of 2.4 years in the challenging superior femoral artery and popliteal arteries, including behind the knee locations.
In addition to the registry arm of the study, the 480 patient randomized component is designed to evaluate the Zilver PTX across 45 trial sites in the U.S., Japan and Europe. Of the 480 patients enrolled in the randomized study, 240 received the Zilver PTX DES.
For more information: www.zilverptxtrial.com