Drug-Coated Balloon Angioplasty Superior for In-Stent Restenosis of SFA, but Results Leave Much To Be Desired

The findings were presented on February 10, 2016, at the International Symposium on Endovascular Therapy (ISET).

Yet despite “beating” balloon angioplasty, outcomes with the drug-coated balloon remain disappointing, with just 40.7% of patients still having a patent vessel 1 year after the procedure. Results were even more dire for those who underwent balloon angioplasty, with slightly more than 13% of patients having a patent SFA at 12 months.

Regarding the secondary endpoint of target lesion revascularization, there was no statistically significant difference between the 2 treatments. Overall, 49.0% of  patients undergoing angioplasty with the drug-coated balloon and 22.0% of patients treated with plain-old balloon angioplasty were free from TLR at 12 months.

“The outcome was significantly better for the drug-eluting balloon, but it wasn’t absolutely convincing,” lead investigator Johannes Lammer, MD, of the Medical University Vienna in Austria, told TCTMD. “With 50% of patients having a recurrence that had to be treated after 1 year, that’s not the best solution. We have to look for better solutions.”

There are currently no data supporting a viable treatment strategy in patients with in-stent restenosis following stent implantation for SFA disease. At 1 year, approximately 1 in 5 patients who receive a stent experience in-stent restenosis, and while there are single-arm/single-center studies suggesting a benefit with drug-coated balloon angioplasty, these data have limitations, said Lammer. To date, many of the drug-coated balloon studies have focused on relatively short, noncalcified native SFA lesions.

With that in mind, the researchers designed the PACUBA trial, a 74-patient study randomizing patients to treatment with the Freeway paclitaxel-eluting balloon (Eurocor Endovascular) versus standard balloon angioplasty for in-stent restenosis of the SFA. Mean lesion length in the SFA was 17.3 cm in the drug-coated balloon arm and 18.4 cm in the plain balloon arm, a nonsignificant difference. Approximately one-third of lesions were class III (totally occluded), and approximately half were diffuse class II (> 50 mm in length). 

Regarding the primary endpoint, the primary patency rate was significantly higher with drug-coated balloon angioplasty. For patients with complete occlusion of the SFA, 36.4% of patients treated with the coated balloon had a patent vessel at 12 months compared with 11.1% of patients treated with a conventional balloon. In the overall population, the patency rates at 1, 6, and 12 months were 97.0%, 58.8%, and 40.7%, respectively. With plain-old balloon angioplasty, the rates were 97.0%, 31.3%, and 13.4%, respectively. Freedom from TLR also declined over time.

Based on the findings, Lammer said plain-old balloon angioplasty “is not the right treatment for patients with in-stent restenosis,” although he added a caveat that the performance of drug-coated balloon in this setting was not very “fascinating” either.

Despite the lack of overwhelming success in this randomized, controlled trial, the paclitaxel-coated balloon (Medtronic) has fared a little better in other reports. In the imaging cohort of the IN.PACT Global study, the rate of clinically-driven TLR was 7.3% at 12 months among patients with in-stent restenosis of SFA treated with the drug-coated balloon. The primary patency rate was reported to be 90% at 12 months. In another single-center report from Italy, Vittoria Virga, MD, University of Messina, and colleagues reported a primary patency rate after 2 years of 70.3% in patients treated with the same drug-eluting balloon.

In the DEBATE-ISR study, which also included patients with in-stent restenosis of the SFA, the rate recurrent restenosis after a paclitaxel-eluting balloon was 19.5% at one year compared with 71.8% in the patients who received plain-old balloon angioplasty. At 3 years, there was catch-up, with the rate of TLR was approximately 40% in both treatment arms, a nonsignificant difference.

‘Very Practical Clinical Problem’

ISET Course Director Barry Katzen, MD, of the Miami Cardiac and Vascular Institute in Florida, told TCTMD that in-stent restenosis of the SFA is a growing problem, with approximately 20% of patients experiencing restenosis. “Even though the frequency of in-stent restenosis is not huge, the number of patients are large,” he said. “It’s a very practical clinical problem. Extending patency is very important. What we have found is that when restenosis starts occurring, it’s really the beginning of a progressive downhill course.”

Based on data from PACUBA, treating clinically meaningful in-stent restenosis with a drug-coated balloon means that 50% of patients require another intervention, such as a second drug-eluting stent, another balloon angioplasty, or laser atherectomy. “It’s always seemed to us that the delivery of antiproliferative agents would be perfectly suited for a process that’s all proliferation,” said Katzen. At their center, patients with in-stent restenosis of the SFA typically receive another stent.

William Gray, MD, Lankenau Heart Institute/Main Line Health (Wynnewood, PA), who presented data on “next-generation” drug-eluting stents, said that outcomes with these devices in the SFA lag behind those in the coronary arteries, possibly because of the mechanical and pathological differences between the vessel beds.

Stents in the SFA need to be strong, flexible, and fracture resistant, he explained. In addition, such stents require an elution profile that matches the disease process common to peripheral disease. For example, restenosis in the coronary arteries mostly occurs in the first 6 months, but in the SFA peak restenosis occurs around 10 or 12 months. As a result, new stents need to have a slower rate of drug release than stents used for coronary disease, said Gray.

Note: Gray is a faculty member of the Cardiovascular Research Foundation, which owns and operates TCTMD.

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Sources
1. Lammer J. DEB for SFA in-stent restenosis: the PACUBA trial. Presented at: International Symposium on Endovascular Therapy; February 10, 2016; Hollywood, FL.
2. Gray W. Drug-eluting stents for PAD: is there a next-generation? Presented at: International Symposium on Endovascular Therapy; February 10, 2016; Hollywood, FL.

Related Stories:

• IN.PACT SAF: Benefits of DCB Persist at 2 Years
• Drug-Eluting Balloon Provides Strong Primary Patency in SFA at 1 Year
• Studies Provide Encouraging Results for DCB in Long SFA Lesions

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