Spectranetics has announced the six month interim results from the Photo-Ablation using the TURBO-Booster and Excimer Laser for In-Stent Restenosis Treatment (PATENT) study.

The PATENT study is designed to assess 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.

The prospective multicentre registry enrolled a total of 90 patients in Leipzig, Germany, and found the target lesion revascularisation (TLR) rate at six months within the PATENT study exceeds the targeted freedom from the TLR rate in the EXCImer laser randomized controlled study for treatment of femoropopliteal in-stent restenosis (EXCITE ISR) trial.

The ongoing EXCITE ISR trial will enroll up to 353 patients to demonstrate the superiority of laser atherectomy plus adjunctive balloon angioplasty for the primary efficacy endpoint of freedom from TLR.

The study demonstrated that percent diameter stenosis was reduced from 87.1% to 7.5%, procedural success rate was 98.8% and cumulative major adverse events (MAEs) were 2.2% through 30 days following the procedure.

In the study, patients with peripheral ISR showed sustained improvement in ankle brachial index (ABI) and walking ability at six months. The PATENT study included patients with peripheral artery disease ranging from intermittent claudication to critical limb ischemia with average total lesion length of 12.5cm.

Ospedale Regionale di Lugano, Lugano Switzerland professor Jos Van Den Berg said the PATENT study shows laser atherectomy for in-stent restenosis lesions can considerably reduce the amount of neointimal hyperplasia with promising TLR rates at six months.

The follow-up PATENT study is expected to be completed in May 2012. Spectranetics develops, manufactures, markets and distributes single-use medical devices used in minimally invasive procedures within the cardiovascular system.