Thirty-Day TOBA Data Presented for Intact's Tack-It System

January 28, 2014—Prof. Thomas Zeller, MD, presented 30-day results from the TOBA trial at LINC 2014: the Leipzig Interventional Course in Leipzig, Germany.

The prospective, single-arm, multicenter TOBA (Tack Optimized Balloon Angioplasty) study is being conducted to collect confirmatory data to support the safety and performance of the Tack-It endovascular system (Intact Vascular, Inc., Wayne, PA) for optimized balloon angioplasty in the superficial femoral and popliteal arteries. The Tack-It endovascular system is not approved for sale in the United States. Coprincipal Investigators Marc Bosiers, MD, and Dierk Scheinert, MD, are leading the study.

At LINC, Prof. Zeller advised that the European TOBA study enrolled 138 patients (65.2% men), with a mean age of 68.3 years between August 2012 and September 2013. Clinical characteristics included diabetes (29.7%), hypertension (79%), hyperlipidemia (66.7%), and being a current smoker (61.5%).

The baseline lesion characteristics included mean lesion lengths of 50.1 mm, with proximal and distal reference vessel diameters of 5 mm and 4.9 mm, respectively. The diameter stenosis was 89.3% before angioplasty and 20.8% after angioplasty. Additionally, 41 patients (29.7%) had moderate/severe calcification.

Of the 138 patients enrolled, 130 (94%) were treated with the Tack-it device. Five other patients had optimal angioplasty results, and three did not meet the study’s inclusion criteria. There were 135 patients (97.8%) available for 30-day follow-up.

Prof. Zeller reported a device technical success rate of 98.5% with 1.7 dissections per lesion and a mean of 3.7 Tacks implanted per patient. The mean procedure time was 49.2 minutes with a mean fluoroscopy time of 11.2 minutes. Interventionists used an ipsilateral approach in 58.5% of the procedures. 

The 30-day safety findings showed that there were no major adverse events (device embolization, need for emergency surgical revascularization, above-the-knee index limb amputation, clinically driven target lesion revascularization). Twelve patients (8.7%) experienced serious adverse events: two pseudoaneurysms, two restenoses of a nontarget vessel (non-Tacked vessel, lesion, or segment), one arterial thrombosis, one cardiac arrhythmia, and six “other” events. Overall, there were 41 adverse events in 33 patients (23.7%).

The ankle brachial index improved by 0.33 from baseline (0.66; n = 132) to 30 days (0.98; n = 125). The measure of walking distance pain improved by a mean of 350.2 meters from baseline (143.9 m; n = 119) to 30 days (461.4 m; n = 11), with 120 patients reporting no pain.

At baseline (n = 138), there were no patients in Rutherford category 0 or 1, but 30 patients (21.7%) in category 2, 101 patients (73.25%) in category 3, and seven patients (5.1%) in category 4. At 30 days (n = 135), there were 90 patients (66.7%) in category 0, 23 patients (17%) in category 1, eight patients (5.9%) in category 2, 12 patients (8.9%) in category 3, and no patients in category 4.

The TOBA investigators concluded that the Tack-It device acutely treated dissection after POBA and demonstrated safety at 30 days with no reports of target lesion/target vessel revascularization, device embolization, amputation, or death. Long-term clinical evidence is needed to confirm the clinical benefits of this new technology, noted Prof. Zeller.