In May 2012, Medtronic will initiate the IN.PACT Global SFA Trial, a single arm, real-world study of the IN.PACT Admiral drug-eluting balloon (DEB) for revascularisation of femoral-popliteal arteries in patients with claudication and rest pain. The study will be part of the company’s drug-eluting balloon programme which already includes eight registries and 10 randomised controlled trials.

The study, which will enrol 1,500 patients across approximately 80 centres, represents the largest study ever conducted in superficial femoral artery revascularisation. The primary endpoint is clinically-driven target lesion revascularisation at 12 months and primary patency at 12 months for the “imaging cohort” with either in-stent restenosis or long lesions >10cm.

This controlled study will have independent monitoring, corelab evaluation and Clinical Event Committee adjudication to contribute to the robustness and reliability of results. Patients will be followed up to five years.

“A single-arm study of this size offers unrivalled value in the assessment of real world population and patient subgroups characterised by either isolated or combined complexities such as long lesions, in-stent restenosis, heavy calcifications, total occlusions etc,” said Gunnar Tepe, chairman of the Study Steering Committee, at CX 2012.

Medtronic’s clinical programme with IN.PACT include:

PACIFIER

This randomised superficial femoral artery trial confirmed the effect of IN.PACT DEB to significantly reduce late lumen loss and restenosis rates at six months vs. angioplasty. With a late lumen loss rate close to zero, PACIFIER reinforced the findings from previously reported drug-eluting balloon trials on the efficacy of drug-eluting balloons in the femoropopliteal bed for symptomatic patients affected by claudication and rest pain.

DEB SFA Italian Registry

In a recent publication (J Am Coll Cardiol Intv 2012;5:331–8), Micari et al described the clinical and functional results at one year of a 105-patient superficial femoral artery series treated with drug-eluting balloons. The study investigators showed a high 83.7% patency rate obtained with IN.PACT Admiral with a remarkably low stent rate of 12.3%, associated with a significant improvement of clinical and functional endpoints including quality of life and walking capacity.

Debulking and drug-eluting balloons Initial data from Thomas Zeller (Bad Krozingen, Germany) and Angelo Cioppa (Mercogliano, Italy) also signal IN.PACT DEB to be an effective adjunctive therapy to atherectomy for the treatment of superficial femoral artery lesions, especially when complicated by severe calcifications.

At LINC 2012, Cioppa reported a 10% restenosis rate at one year from his 30 patient series whereas Zeller presented his experience on 29 drug-eluting balloon patients after atherectomy. At one year, primary patency was at 88% with combined debulking and drug-eluting balloon treatment.

DEB in in-stent restenosis

While four trials are currently ongoing evaluating IN.PACT in superficial femoral artery in-stent restenosis, initial insights for this indication were given by Stabile at LINC 2012, where he presented his experience of 39 patients with superficial femoral artery in-stent restenosis. At one-year follow-up, he reported a low target lesion revascularisation rate of 7.9%.

DEB below the knee

Further down to infrapopliteal vessels, the results from the published Leipzig DEB BtK Registry (Schmidt et al, J Am Coll Cardiol 2011;58:1105-9) show a low 27.4% restenosis rate at three-month angiography in complex and long (average 176±88mm) below-the-knee lesions and occlusions.

Results appear particularly convincing when benchmarked to an historical similar patient group treated with angioplasty. Francesco Liistro (Arezzo, Italy) presented preliminary results of the DEBATE BTK randomised trial of IN.PACT Amphirion vs. standard angioplasty for the treatment of below-the-knee lesions in patients affected by critical limb ischaemia and diabetes.

With a lesion length of 121 and 123mm respectively, restenosis (29% vs. 72%; p<0.001) and occlusion rates (14 vs. 50%; p<0.001) both showed highly significant differences in favour of DEB at one-year follow-up.

DEB in arteriovenous shunts

Katsanos (Patras, Greece) presented the results of a randomised trial of IN.PACT Admiral vs. standard angioplasty for the treatment of dysfunctional arteriovenous fistulae reporting a significant improvement in patency rates in favour of drug-eluting balloons at six months. While further clinical research is warranted and underway the unceasing, broadly emerging evidence around IN.PACT DEB continues to enforce trust and boost adoption to address the daily challenges of peripheral arterial disease. Optimal percutaneous transluminal angioplasty concept and practice is being re-evaluated and the value of “leave nothing behind” reappraised for the long term benefit of patients.