The Abre venous stent demonstrated three-year primary patency rates of 97.1%, 76.5% and 70.4% respectively for non-thrombotic iliac vein lesion (NIVL), acute deep vein thrombosis (DVT), and post-thrombotic syndrome (PTS) patient populations within the ABRE clinical study, a late-breaking session at The VEINS (Venous Endovascular Interventional Strategies) 2022 conference (Oct. 30–31) in Las Vegas heard.
Presenter Stephen Black, MD, from Guy’s and St Thomas’ Hospital in London, England, delivered the breakdown of clinical outcomes from the trial based on initial clinical presentation two weeks after revealing an overall effectiveness rate through 36 months of 81.6% and a freedom from clinically driven target lesion revascularization (CD-TLR) rate of 89.3% at the American Vein and Lymphatic Society (AVLS) 2022 annual meeting (Oct. 13–16) in New Orleans. The data show that the “struggle to maintain patency” largely rests in the PTS patient population, Black noted.
The multicenter study enrolled 200 patients at 24 sites—16 in the U.S. and eight in the European Union. Some 47.5% of the pool was made up of PTS patients, with 36% presenting with NIVLs and 16.5% with acute DVTs. Furthermore, Black reported that 88 of the subjects, 44% of the study population, were fitted with a stent extending below the inguinal ligament—70.5% of them in PTS patients.
In terms of secondary endpoints, Black revealed that the study showed no stent fractures through three years, and similarly, no delayed stent migrations. “This speaks to the topic we’ve been continuing to discuss: that stent migration really does seem to be an operator issue rather than a stent issue,” Black told The VEINS 2022 attendees.
Quality-of-life assessments showed a “steep increase” in the first six months, which “was maintained through all the follow-up time points [12, 24 and 36 months] for all the population subgroups, acute DVT, PTS and NIVL,” he said. The same was true for functional assessments of the venous system, Black added.
“This was a challenging and complex patient population, with a significant number of patients with PTS with stent extension into the common femoral vein below the inguinal ligament,” he concluded of the subgroup analysis. “[We saw] a sustained primary patency out to 36 months, with the NIVL group in particular performing well. There have been no issues with stent integrity in terms of fracture or delayed stent migration through 36 months.
“And, most importantly, [we saw] improved quality of life in all presenting subgroups maintained throughout the follow-up period, with similar in venous function.”
Session panelist Raghu Kolluri, MD, from OhioHealth in Columbus, Ohio, asked Black where this data places the Abre device in the larger landscape of venous stents. “All the IDE [investigational device exemption] studies show similar results,” Black responded. “The performance in the NIVL group has been excellent, with drop offs in the acute DVT and PTS groups that we’ve seen before. So, where does it fit? It just adds to the data we now have to say that treating patients with chronic disease is sustainable and improves quality of life. We need to continue with randomized trials to really give us that weight of evidence.”
The study also reiterated the challenges of the PTS population, Black added. “A 30% patency loss at 36 months is something we probably need to improve,” something true “of all the other studies as well.”
