The Next Generation of Stents for the Lower Extremity: What s on the Horizon?

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1 The Next Generation of Stents for the Lower Extremity: What s on the Horizon? PNEC 2017 Pacific Northwest Vascular Conference Thursday, May 25, 2017 Seattle, WA Brian DeRubertis, MD, FACS Associate Professor of Surgery UCLA Division of Vascular Surgery 1

2 DISCLOSURES Brian DeRubertis, MD Consultant/Advisory Board: Medtronic, Abbott, Cook Medical Speakers Bureau: Medtronic, Abbott Will be discussing off-label use of devices

3 Limitations of 1 st Generation Stents Not designed for the SFA or vascular beds Laser cut from cylindrical nitinol tubes Limited flexibility or tolerance for torsion Minimal kink resistance Stent properties may contribute to late failures Stent failures can have implications to re-treatment 3

4 Limitations of 1 st Generation Stents LEVANT Global 1 IN.PACT Global Full Clinical Cohort 2 IN.PACT Global Long Lesion 3 IN.PACT Global CTO 4 IN.PACT Global ISR 5 Key Lesion Characteristics Length (cm) CTO (%) Ca 2+ (%) 10.1cm 30.9% 34.2% 12.1cm 35.5% 68.7% 26.4cm 60.4% 71.8% 22.9 cm 100.0% 71.2% 17.2cm 34.0% 59.1% Primary Patency FF TLR/CD-TLR 91.0% 92.0% % 91.1% 94.0% 84.4% 88.2% 88.7% 92.9% Bail-out Stent (%) 27.6% 25.3% 40.4% 46.8% 14.5% Continued need for scaffolding in complex lesions 1. Presented by Laurich C, SVS Chicago Presented by Jaff M, VIVA Las Vegas Presented by Scheinert D, PCR Paris Presented by Tepe G, CX London 2016.] 5. Presented by Brodmann M, VIVA Las Vegas

5 Limitations of 1 st Generation Stents Mechanical scaffolding remains necessary in complex real-world lesions Full metal jackets of the SFA is now recognized as a less than ideal treatment paradigm in most patients Stents should provide the mechanical characteristics we desire without serving as a source of chronic inflammation / irritation to the vessel

6 Limitations of 1 st Generation Stents Potential Improvements in Current Stent Technology Improved flexibility / conformability Improved kink resistance Improved crush resistance Decreased susceptibility to intimal hyperplasia Paclitaxol coating Paclitaxol / Everolimus + Polymer

7 Commercially-Available Nitinol Wire Stents Supera Stent (Abbott Vascular) When nominally deployed: 1 91% 12mo Primary Patency 94% 36mo Freedom from TLR 1 Data from Superb Trial, Presented at VIVA 2015

8 Commercially-Available Nitinol Wire Stents Tigris Stent (WL Gore) Tigris Lifestent P-value Lesion Length 10.7 cm 11.8 cm 0.29 Stented Length 12.9 cm 14.9 cm 0.06 Occlusions 42% 37% 2-yr Primary Patency (KM) 2-yr Freedom from TLR 63% 67% NS 77% 81% NS Stent Fractures 0% 29% <0.001 Tigris Stent with nitinol wire scaffold and heparin-bonded PTFE coating RCT 3:1 Tigris (Gore) vs Lifestent (Bard) 274 patients randomized 1 Data from Tigris IDE Trial, Presented by John Laird, MD at VIVA 2016

9 Newly-Designed Laser Cut Technology Biomimics 3D Stent (Veryan) Helical centerline geometry with spiral pattern to the connecting bars between struts Promotes spiral flow Mimics Trial: RCT vs standard BMS at 8 German centers; 76 pts; 72% vs 55% two-year primary patency (0.49)

10 Next Generation Stent Systems for Non-Coronary Lesions: Limitations of 1 st Generation Stents Potential Improvements in Current Stent Technology Improved flexibility / conformability Improved kink resistance Improved crush resistance Decreased susceptibility to intimal hyperplasia Paclitaxol coating Paclitaxol + Polymer

11 Investigational Laser Cut Nitinol Stents Eluvia (Boston Scientific) Majestic Feasibility Eluvia DES (n=57) Lesion Length 7.1 cm 6.6 cm Zilver PTX RCT DES Arm (n=241) CD-TLR 12mo 3.8% 9.5% 24mo 7.5% 13.4% 36mo NR 16.0% Primary Patency 12mo 96.1% 83.1% 24mo 78.2% 74.8% 36mo NR 68.7% Laser-cut nitinol stent with interconnecting bars and strut angles designed for optimizing radial force and flexibility Paclitaxel and polymer coating IMPERIAL IDE trial with 2:1 randomization to Zilver PTX

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13 5 Years Day 1 6 mo 2 yr 5 yr Courtesy of RJ van Geuns, Erasmus Medical Center, Netherlands

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15 Stanza Scaffold (480 Biomedical) PLGA Scaffold Self-expanding bioresorbable scaffold PLGA and paclitaxol coating Flexibility and stiffness of self-expanding metallic stents Delivery through retractable sheath system Resorption over 6-12 months SPRINT Trial Prospective single-arm multicenter OUS trial Endpoint: MAE at 6m; patency/qol at 6, 12, 24m Ongoing enrollment

16 Espirit Scaffold (Abbott) PLGA Scaffold Balloon-expandable bioresorbable scaffold PLLA scaffold backbone Polymer-based everolimus coating Resorption over 6-12 months ESPRIT Trial Prospective European non-randomized trial; 35pts SFA (89%) and EIA (11%) TLR of 88.1% at 2yrs sustained at 3y time point Proper sizing and wall-apposition key to patency

17 ABSORB GT1 BVS (Abbott) PLLA Scaffold Semi-crystalline poly-l-lactide backbone Provides device structure Developed to optimize radial strength Everolimus / PDLLA Matrix Coating 2-4μm amorphous (non-crystalline) coating Poly-L,D-lactide matrix/everolimus at 1:1 ratio Provides controlled drug release

18 OCT for size assessment of reference vessel diameter Focal predilatation with noncompliant 3.0x20 balloon

19 3.0x28mm ABSORB GT1 Balloon marker Platinum Scaffold markers Balloon marker

20 Slow, controlled deployment to nominal diameter 2ATM increase every 5sec Post-dilate with 3.5x20 non-compliant balloon

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23 Post-dilate with NC 3.5x20 balloon Predilate with 2.75x20 NC Trek ABSORB GT1 3.0x28 Scaffold

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25 38 limbs in 33 patients 50 scaffolds implanted 43 infrageniculate lesions Mean lesion length 1.9cm 68% CLI, 32% Claudication Primary Patency (KM) 12mo 96% 24mo 85% Freedom from CD-TLR 12mo 96% 24mo 96%

26 One patient with acute thrombosis of 2 scaffolds immediately postop, likely due to absence of any antiplatelet therapy

27 ABSORB II and III Trials Increased risk of late stent thrombosis compared to Xience in coronaries Appears to be related to stent implantation technique Decreased rates in later stages of trials with standardized deployment methods

28 Conclusions Paradigm shift away from full metal jacket of the SFA Need for scaffolding continues in long and complex lesions Next generation stents may offer improved results over last decade s laser cut nitinol stents Bioresorbable technology with drug elution may be the next frontier both above and below the knee