It was announced today at the 2019 Vascular Interventional Advances conference (VIVA) (4–7 November, Las Vegas, USA) that, through six months, TOBA II BTK met all endpoints in a 100% dissected vessel population.
This prospective, multicentre, single-arm global pivotal study was designed to investigate the safety and effectiveness of the Tack endovascular system (Intact Vascular) to repair dissections in below-the-knee (BTK) arteries. Primary safety and efficacy endpoints were analysed at six months and compared with performance goals derived from the critical limb ischemia (CLI) literature.
It was concluded that high rates of dissection resolution, wound improvement, and freedom from clinically-driven target lesion revascularisation (CD-TLR) support the Tack system as an ideal adjunct to PTA and potentially as the first permanent vascular implant to improve results of infrapopliteal angioplasty.
In more detail, TOBA II BTK met both primary endpoints (p<0.0001) of safety (30-day major adverse limb event or perioperative death) and efficacy (six-month major adverse limb event or 30-day perioperative death). All (100%) dissections were resolved following Tack implantation, with 92.0% 6-month Kaplan-Meier freedom from CD-TLR, 87.3% 6-month Kaplan-Meier target lesion patency, and 95.7% 6-month Kaplan-Meier amputation-free survival. Wounds were healed or improved in 73.8% and Rutherford category was ≤3 at six months in 74% of CLI patients.
TOBA II BTK is the first investigational device exemption clinical trial approved to investigate safety and effectiveness of a permanent implant to repair dissections in BTK arteries. The study evaluated the Tack system 233 patients who had ≥1 dissection requiring repair after PTA in the mid/distal popliteal, tibial, and/peroneal arteries. There were 918 Tacks implanted from the mid popliteal to 1 cm above the tibiotalar joint, with 122 placed in the distal third of the vessels.
The Tack system has four preloaded self-expanding nitinol implants on a single catheter. Each implant is 6mm long and self sizes to vessels ranging from 1.5 to 4.5mm in diameter, using sufficient radial force to appose dissected tissue against the vessel wall.