CLINICAL FEATURES

Real-World Comparison of IN.PACT vs Lutonix Drug-Coated Balloons in Complex Lesions

March 3, 2016
Authors: 

Cath Lab Digest talks with Sabine Steiner, MD, MSc 
Department of Interventional Angiology, Medical University Leipzig, Germany.

Can you tell us about the cath labs at the University Hospital Leipzig?

We have two cath labs with a 24/7 on-call service and perform the full range of endovascular peripheral interventions including revascularizations of complex, chronic total occlusions, carotid and visceral interventions, as well as endovascular aortic repair procedures.

Do you have a surgical or interventional background?

We have a specialty in Germany called angiology. You first do a specialization in internal medicine, and then head into angiology, which is dominated by interventional vascular medicine with a focus on non-cardiac vessels. 

What prompted your retrospective study of two drug-coated balloons?

We have several drug-coated balloons (DCBs) available now for clinical routine use in femoropopliteal interventions and I think we are all aware that they showed very promising results in randomized studies compared to standard balloon angioplasty. Yet, so far, we do not have randomized data comparing two types of drug-coated balloons in a head-to-head trial. As there are no comparative effectiveness studies, there is a high interest on the performance of the various DCBs against each other. Since we started using DCBs rather early on, we thought we would look into our database and do a non-randomized comparison of our cohorts, looking at symptomatic peripheral arterial disease patients undergoing femoropopliteal interventions with either the IN.PACT drug-coated balloon (Medtronic) or the Lutonix drug-coated balloon (Bard Peripheral Vascular). We started these cohorts in mid-2013 and included patients until the end of 2014, yielding at least one year follow-up until the end of 2015. Our study included 281 patients undergoing treatment with the IN.PACT drug-coated in 366 limbs. We also have about 137 patients treated with the Lutonix drug-coated balloon in 168 limbs. Our results were first presented at the LINC (Leipzig Interventional Course) meeting in January this year and what we are discussing is an overview of this presentation.

Was the choice of the drug-coated balloon based solely on operator preference?

Yes, it was based on both operator preference and balloon availability. This study was really outside the clinical trials; this was real-world use as decided by the operators.

Can you describe the lesions included in the study?

In about 40-45% of lesions, total chronic occlusions were treated and almost 20% of our patients underwent treatment of in-stent restenosis. As this is a retrospective cohort study, we do not have detailed information on lesion length, but for this analysis we added up the cumulative lengths of devices that were used. The mean device length required for treatment of our patients was 29 cm, so we can assume that quite long lesions were included. There was a high stent implantation rate of around 50%, also highlighting the complexity of these lesions. This percentage is clearly higher than in the randomized, controlled trials, which included shorter lesions. We are performing mechanical debulking with increasing frequency prior to the use of DCBs, using atherectomy or thrombectomy devices such as the Turbohawk (ev3/Medtronic) or Rotarex (Straub Medical AG) device in about 30% of cases. Also, in about one-third of patients, the popliteal segment was treated during the intervention.

Why has use of mechanical debulking increased prior to DCB use?

Vessel preparation is crucial before the use of a DCB, either by standard angioplasty or by mechanical debulking. In our data set, the rate of atherectomy/thrombectomy was about 26% for Lutonix cases. With the IN.PACT DCB, the rate was about 37%, highlighting an increasing rate of mechanical debulking prior to DCB use.

What are your standard inflation times for DCBs?

The minimum inflation time is 60 seconds as recommended by the manufacturers, but usually we tend to inflate longer, typically for 3 minutes. We have done this now for the past few years and continue to follow this concept.

How did each DCB perform in the study? 

Both DCBs performed very well in this real-world study. Mean follow-up was around 19 months in the Lutonix DCB group and 11 months in the IN.PACT DCB group. The most relevant question for us was target lesion revascularization (TLR), since this is a clinical endpoint particularly important to our patients. We performed a time-to-event analysis looking at TLR and saw very promising results for both DCBs, and importantly, no statistical difference was noted between the IN.PACT and Lutonix DCB groups: Kaplan-Meier estimates demonstrated freedom from TLR in 89% of lesions in the IN.PACT DCB group and 83% in the Lutonix group after one year, and in 75% and 73% after 18 months, respectively (Figure 1).

We also looked at clinical outcome, defined as a sustained, TLR-free improvement of Rutherford classification, with a reassuring 80 to 81% for both DCBs after 1 year.

What do you think about the study results?

Overall, our study results are promising, but we still have to improve clinical outcomes for our patients. We still need more long-term data for DCBs and especially for long lesions a variety of devices are necessary to achieve good individual results. One good option might be a combination of mechanical debulking and DCBs, although we do not have enough randomized data to support this strategy. We also learned that some lesions do not respond very well to angioplasty alone, and might require stenting and mechanical support, favoring the use of stents with a high radial force, especially in heavily calcified lesions. I believe that the approach for each patient will become increasingly personalized as we gain more and more experience. It is certainly worth exploring different comparisons of various devices in clinical trials. Thus, it also would be very interesting to see how DCBs perform against a primary stenting strategy with drug-eluting stents, especially in long lesions. 

What about diabetics?

We didn’t look specifically at diabetics, but what we do know that restenosis rates are even higher in this patient population. Today, we do not have a specific approach for diabetic patients with drug-eluting technologies, but this is something we also should explore.

How has this study impacted your practice?

Keeping the limitations of this non-randomized, retrospective, monocenter cohort study in mind, the results are very reasssuring. Both DCBs showed good clinical effectiveness. We understand that it is important to perform some kind of lesion preparation, so that you can be sure that you are able to bring the drug to the vessel segment where it is needed and you are not shedding it beforehand. Both DCBs are valid and very practical choices, and either can be part of a feasible strategy. 

Disclosure: Dr. Steiner reports she is a consultant for Abbott and C.R. Bard.

Dr. Sabine Steiner can be contacted at sabine.steiner@medizin.uni-leipzig.de.