Outcomes and Comparative Analysis of the Initial Results of Standard Balloon Angioplasty Versus Drug-Coated Balloons Alone Versus in Association With Laser-Excimer Atherectomy in the Treatment of Femoropopliteal Artery In-Stent Restenosis (INTACT)

Background: Despite improved patency with newer-generation nitinol stents, one-half of patients will require secondary interventions for in-stent restenosis (ISR). The best treatment strategy remains unclear. This study aimed to compare drug-coated balloons (DCBs) used alone or in association with excimer laser atherectomy (ELA) to simple percutaneous transluminal angioplasty (PTA) in the treatment of femoropopliteal-ISR.

Methods: The INTACT trial is a multicenter, prospective, triple-arm randomized trial conducted across 14 centers from December 2015 to November 2019. Patients Rutherford Class 2-5 with ISR≥70% were followed-up for 18 months. The primary efficacy endpoint was recurrent ISR>70% by duplex ultrasound analysis. The primary safety endpoint was major adverse events (MAEs) defined as death, major amputation, or target lesion revascularization (TLR).

Results: Around 134 subjects were randomized to PTA alone (n=41), PTA+DCB (n=43) or PTA+ELA+DCB (n=50). Procedural success was similar (p=.74), as was clinical success (p=.17). The number of recurrent ISR>70% decreased after PTA+ELA+DCB (30.0%; p=.04) and PTA+DCB (30.2%; p=.05) compared to PTA alone (51.2%). Primary patency was higher after PTA+ELA+DCB (log-rank p=.04) and PTA+DCB (log-rank p=.02) compared to PTA alone at 12 months (78.7% and 70.4% vs 61.5%) and 18 months (61.6% and 67.7% vs 37.3%). Freedom from MAEs was lower after PTA+DCB (27.9%) compared to PTA alone (53.7%; p=.02) but did not differ with PTA+ELA+DCB (40.0%). It was primarily driven by TLR; 2 major amputations occurred after PTA+ELA+DCB (4.0%; p=.18).

Conclusion: This independent study demonstrated a decrease in recurrent ISR>70% and increase in primary patency up to 18 months after PTA+ELA+DCB and PTA+DCB compared to PTA alone in the treatment of FP-ISR. It did not show an increase in MAEs but could have lacked power.

Clinical impact: This multicenter, prospective, triple-arm randomized, controlled trial focuses on the results of adjunctive therapies, such as excimer laser atherectomy (ELA) and/or drug-coated balloons (DCBs) in the treatment of in-stent restenosis (ISR) in femoropopliteal lesions in 134 patients. It has the originality of being an independent study funded by a grant from the French Ministry of Health. This study confirms a significant decrease in recurrent ISR >70% and increase in primary patency up to 18 months after the use of ELA+DCB and DCBs compared to simple percutaneous transluminal angioplasty in the treatment of femoropopliteal ISR without an increase in major adverse events.