Philips Announces Three-Year Results From Its Tack Optimized Balloon Angioplasty (TOBA) II Below-The-Knee (BTK) Clinical Trial

Royal Philips announced the latest results from the Tack Optimized Balloon Angioplasty (TOBA) II below-the-knee (BTK) clinical trial, demonstrating that the Philips endovascular system – Tack (4F) – provides a sustained treatment effect and positive impact on quality of life for patients with critical limb ischemia (CLI), a severe stage of peripheral arterial disease (PAD), out to three years of clinical follow-up.

CLI occurs when an obstruction in an artery severely reduces blood flow, causing painful wounds, debilitating rest pain, recurring ulcers and life-threatening infection. If left untreated, 50% of patients with CLI will undergo an amputation or die within the first year, according to previously published guidelines.

The TOBA II BTK trial studied the safety and efficacy of post-angioplasty dissection repair using the Philips Tack endovascular system in patients with CLI and infrapopliteal disease. Endpoints included rates of major adverse events, target lesion revascularization (TLR), target limb salvage (TLS) and quality of life (QoL) metrics.  The Tack endovascular system is a unique specialized implantable device to optimize the treatment of dissections in patients with CLI. Tack endovascular system is the first and only device of its kind approved by the US FDA.

“Based on 36-month follow-up in the TOBA II BTK trial, which is following 233 patients at 41 sites internationally, the Tack endovascular system offers a new standard in repairing below-the-knee arterial dissections,” said co-principal investigator George Adams, M.D., director of cardiovascular and peripheral vascular research at UNC Rex Hospital in Raleigh, N.C., and clinical associate professor of medicine at the University of North Carolina at Chapel Hill, who presented the results to hundreds of interventional cardiologists, interventional radiologists and vascular surgeons at the New Cardiovascular Horizons (NCVH) conference in New Orleans, USA, on June 2. 

Adams added: “The device stands to significantly benefit patients with CLI whose treatment with balloon angioplasty often leads to this particular complication, which typically goes untreated and unaddressed, to the detriment of long-term clinical outcomes.”

The three-year analysis of TOBA II BTK results includes the following clinical insights on the Tack endovascular system:

• 93.9% target limb salvage in CLI patients at three years
• 69.6% freedom from clinically-driven target lesion revascularization across all patients at three years
• Sustained improvement in established clinical classification systems including the Rutherford clinical category and hemodynamics in ankle- and toe-brachial indices
• Sustained improvement in patient-reported quality-of-life and mobility measures

“In treating peripheral arterial disease below the knee with balloon angioplasty, dissections of the popliteal, tibial and peroneal arteries occur with considerable frequency,” explained Chris Landon, business leader of Image Guided Therapy Devices at Philips. “With the Tack endovascular system from Philips, interventionists can reliably repair below-the-knee arterial dissections – and in doing so, improve major amputation rates and quality of life.”

Philips has previously reported data from the TOBA II and III studies, which evaluated the Tack endovascular system for superficial femoral and proximal popliteal artery dissection repair following uncoated balloon angioplasty and/or drug-coated balloon (DCB) angioplasty. These multicenter, global and European studies demonstrated that the use of the Tack endovascular system resulted in overwhelming dissection resolution following uncoated or DCB angioplasty.

In TOBA II, which involved uncoated and drug-coated balloons, dissection repair with the Tack System resulted in 89.6% and 86.5% 12-month primary patency (uncoated balloon group) and freedom from CD-TLR.

In TOBA III, which involved drug-coated balloons, dissection repair with the Tack endovascular system resulted in 95.0% and 97.5% 12-month primary patency and freedom from CD-TLR.

There were no major adverse events reported through 30 days in either study.

Together, the TOBA II, TOBA III and TOBA II BTK trials support the safety and efficacy of the Tack endovascular system for post-PTA dissection repair in above- and below-the-knee arterial disease. The 36-month TOBA II BTK data reported at NCVH adds to the robust body of clinical evidence supporting the safety and effectiveness of the Tack Endovascular System in both vessel beds.