October 31, 2023

Second Round of Late-Breaking Clinical Trial Results Announced at VIVA23

The VIVA Foundation, a not-for-profit organization dedicated to advancing the field of vascular medicine and intervention through education and research, announces the results for the second of four Late-Breaking Clinical Trial sessions at the VIVA23 conference, hosted at Wynn Las Vegas.

VIVA (Vascular InterVentional Advances) is an annual vascular education symposium that brings together a global, multispecialty faculty to present a variety of talks and live case presentations from clinical centers around the world. Attendees include an audience of interventional cardiologists, interventional radiologists, vascular surgeons, and endovascular medicine specialists. Below are highlights of this afternoon's 3 late-breaking clinical trial presentations.

Wound Assessment and Outcomes in the LIFE-BTK Randomized Controlled Trial Evaluating the Esprit BTK™ Drug-Eluting Resorbable Scaffold
Presented by: Raghu Kolluri, MD, MS

Results from Abbott’s LIFE-BTK randomized clinical trial (RCT) demonstrate that Esprit BTK (Abbott) reduces disease progression and helps improve medical outcomes compared to balloon angioplasty, the current state of care. Abbott’s landmark LIFE-BTK trial met its primary safety and efficacy endpoints, demonstrating that Esprit BTK offers significant advancements in opening blocked below-the-knee arteries and maintaining patency compared to balloon angioplasty alone. LIFE-BTK data underscore the profound impact that Esprit BTK, if approved, could have for the more than 200 million people worldwide with peripheral artery disease (PAD).

LIFE-BTK is the first RCT that collected comprehensive wound data from the chronic limb-threatening ischemia (CLTI) population, people who have a serious form of PAD with severe blockage in the arteries of the lower extremities, which reduces blood flow. In the LIFE-BTK trial, wound assessment was not a prespecified powered primary or secondary endpoint but rather a prespecified descriptive endpoint. It is important for the trial as there is not much evidence from other trials assessing wounds. The trial offers the largest ischemic wound data set to date, collected systematically and adjudicated independently in a blinded fashion.

Wound care is an important aspect of CLTI care, as CLTI can lead to nonhealing wounds due to the reduced blood flow to the affected limb. Wound care is critical to prevent infections, promote healing, prevent further tissue damage, and minimize amputation rates.

The wound data were assessed by experts at the wound core laboratory. The healing of the index wounds showed improvement in both arms, and the occurrence of new wounds was comparable, with no statistical difference between arms. This result highlights the fact that revascularization is not the sole factor influencing wound healing. Additionally, it has been further demonstrated that the resorbable scaffold with an olimus-based antiproliferation drug was not associated with any disruption in wound healing over a period of time.

RESOLV FIH 6-Month Results by Rutherford Classification
Presented by: Marianne Brodmann, MD

The Magnitude thin-strut 98-μm drug-eluting bioresorbable scaffold (BRS; R3 Vascular) offers the potential for higher vessel patency in the treatment of below-the-knee arteries. The 6-month results from an ongoing first-in-human study are presented for 30 treated patients, stratified by the baseline Rutherford classification.

Patients included in the RESOLV study were Rutherford category 3 to 5, with lesions up to 12 cm in the tibioperoneal trunk, posterior tibial artery, anterior tibial artery, and peroneal artery. Angiography and intravascular ultrasound (IVUS) were used to identify vessel characteristics and morphology.

At baseline, the Rutherford category 3 cohort (5/30, 17%) had a total of five lesions treated, a mean age of 76.8 (± 6.0) years, and a mean body mass index (BMI) of 23.9 (± 3.5) kg/m2. The mean proximal vessel diameter by IVUS was 4.1 mm, and the mean in-segment diameter stenosis was 80.1% prior to treatment, decreasing to 16.6% following scaffold implantation and increasing slightly to 23.0% at 6 months.

Rutherford category 4 cohort (3/30, 10%), at baseline, had a total of three lesions treated, a mean age of 74.3 (± 6.3) years, and a mean BMI of 32.7 (± 3.7) kg/m2. The mean proximal vessel diameter by IVUS was 4.1 mm, and the mean in-segment diameter stenosis was 77.7% prior to treatment, decreasing to 7.9% following scaffold implantation and increasing slightly to 25.4% at 6 months.

At screening, the Rutherford category 5 cohort (22/30, 73%) had a total 23 lesions treated, a mean age of 74.5 (± 5.8) years, and a mean BMI of 28.2 (± 5.8) kg/m2. The mean proximal vessel diameter by IVUS was 4.3 mm, and the mean in-segment diameter stenosis was 78.4% prior to treatment, decreasing to 14.8% following scaffold implantation and increasing slightly to 28.8% at 6 months.

Overall, across severity of PAD by Rutherford class, significant improvement was seen following placement of the Magnitude BRS, with sustained patency by angiography at 6 months.

IN.PACT AV Access Trial Thrombosis Predictors
Presented by: Robert Lookstein, MD, MHCDL

Thrombotic events in arteriovenous fistulas (AVFs) used for dialysis are associated with high rates of access loss, additional procedure cost, poor long-term patency, and higher mortality rates. However, patient, lesion, and procedural characteristics associated with thromboses are not well understood and are rarely reported in prospective randomized controlled trials (RCTs). This post hoc analysis reports differences in IN.PACT AV Access study participants who eventually had a thrombosis versus those who did not.

The IN.PACT AV Access study is a multicenter, single-blinded RCT of end-stage kidney disease patients with de novo or obstructive native AVF from the United States, Japan, and New Zealand. Serious adverse events, including access circuit thrombosis, were independently adjudicated. A multivariable analysis was conducted to assess factors associated with access circuit thrombosis through 36 months.

The cumulative incidence of access circuit thrombosis through 36 months in the IN.PACT AV Access study was 8.2% in the drug-coated balloon (DCB) group compared to 18.3% in the percutaneous transluminal angioplasty (PTA) group based on Kaplan-Meier estimates (log-rank P = .040). A post hoc multivariable analysis of all participants suggested that predictors of a higher risk of access circuit thrombosis were two or more reinterventions in the year prior to the index procedure, upper arm AVF type, higher preprocedural diameter stenosis of the target lesion, and treatment with PTA.

In the IN.PACT AV Access trial, cumulative incidence of thrombosis through 36 months was lower in the DCB group compared to the PTA group. After conducting a multivariable analysis, four variables were retained and appear to be associated with higher access circuit thrombosis through 36 months. Due to the costs and patient impact associated with access circuit thrombosis as well as the post hoc approach, these results should be further studied in larger populations.

About the VIVA Foundation

The VIVA Foundation, a not-for-profit organization dedicated to advancing the field of vascular medicine and intervention through education and research, strives to be the premier educator in the field. Our team of specialists in vascular medicine, interventional cardiology, interventional radiology, and vascular surgery is driven by the passion to advance the field and improve patient outcomes. Educational events presented by the VIVA Foundation have a distinct spirit of collegiality attained by synergizing collective talents to promote awareness and innovative therapeutic options for vascular disease worldwide.

To learn more about the VIVA Foundation, visit https://viva-foundation.org/.