Spectranetics Corporation (Nasdaq:SPNC) today announced six month interim results from the PATENT (Photo-Ablation using the TURBO-Booster® and Excimer Laser for In-Stent Restenosis Treatment) study evaluating the safety and efficacy of the Spectranetics peripheral laser atherectomy catheters for the treatment of in-stent restenosis (ISR) in the femoropopliteal artery in the leg. There is no device currently cleared or approved by the FDA to treat peripheral in-stent restenosis, which remains a major unsolved medical problem.
Total enrollment of 90 patients in this prospective, multi-center registry, was completed in December of 2011 at five centers in Germany. Seventy-eight (78) patients have been followed through six months. Interim results presented at LINC 2012 in Leipzig, Germany indicate 76% freedom from target lesion revascularization (TLR) at six months. Notably, the freedom from TLR rate within the PATENT study exceeds the targeted freedom from TLR rate in the randomized controlled EXCITE ISR (EXCImer Laser Randomized Controlled Study for Treatment of Femoropopliteal In-Stent Restenosis) trial, a landmark study currently underway in the U.S., providing confidence in the EXCITE ISR trial design.
The EXCITE ISR trial will enroll up to 353 patients with chronic peripheral artery disease (PAD) associated with femoropopliteal artery in-stent restenosis at 30 centers in the United States. Patients are randomized in a 2:1 allocation to either laser atherectomy with adjunctive balloon angioplasty or balloon angioplasty alone. The study is designed to show superiority of laser atherectomy plus adjunctive balloon angioplasty for the primary efficacy endpoint of freedom from TLR.
"The PATENT study shows that laser atherectomy for in-stent restenosis lesions can significantly reduce the amount of neointimal hyperplasia with promising TLR rates at six months. We look forward to the twelve month results," said Dr. Jos Van Den Berg of Ospedale Regionale di Lugano, Lugano Switzerland, who presented the interim results.
In the PATENT Study, percent diameter stenosis was reduced from 87.1% to 7.5% post-laser atherectomy and balloon angioplasty as measured by angiographic core lab. Procedural success rate, defined as achievement of ≤ 30% final residual restenosis was 98.8%, and Cumulative Major Adverse Events (MAEs) were 2.2% from procedure through 30 days following the procedure. Patients saw significant and sustained improvement in ankle brachial index (ABI) and walking ability at 6 months.
"We are encouraged by the interim results of the PATENT study. The data reinforces the perspective of Spectranetics and thought leaders that debulking with laser prior to adjunctive therapy provides better results for patients. This is a powerful part of our vision to improve patients' lives and eradicate amputation," said Scott Drake, CEO of Spectranetics.
The study population included patients with PAD ranging from intermittent claudication to critical limb ischemia (Rutherford class 2-5). Lesions ranged from 1cm to 25cm with average total lesion length of 12.5cm, and 93% were in the superficial femoral artery (SFA). Nearly 37% of patients had total occlusions. All patients had stents, 50% of patients were diabetics, and 35% had previously been treated for in-stent restenosis using other therapies.
The PATENT Study follow up will be completed in May 2012, and Spectranetics will collaborate with the physician investigators to publish complete study results thereafter.
The Company is also supporting a physician initiated pilot study in four centers in Europe evaluating the use of laser ablation followed by a paclitaxel-coated angioplasty balloon (PTX PTA) compared with the use of PTX PTA alone in the treatment of in-stent lesions in above-the-knee arteries. The first of 50 planned patients was recently enrolled. Spectranetics' support of the PHOTOPAC (Photoablation Followed by a Paclitaxel-Coated Balloon to Inhibit Restenosis in Instent Femoropopliteal Obstructions) trial is in the form of an unrestricted research grant.
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