Lichtenberg: MIMICS-3D: Two-Year Clinical Outcomes for the BioMimics 3D Stent

Principal investigator Michael Lichtenberg, MD, from the Klinikum Hochsauerland in Arnsberg, Germany presented in-person and online attendees of AMP 2021 with 2-year data for the MIMICS-3D Trial, which evaluated the BioMimics 3D stent in a real-world population.

The BioMimics 3D Vascular Stent System (Veryan Medical) incorporates a unique 3-dimension geometry that imparts a gentle helical shape to the stented artery that promotes swirling flow. Swirling flow increases wall shear stress on endothelial cells, which has been shown by Caro et al in 2013, to reduce intimal hyperplasia, providing an antiproliferative effect without the need for a drug.

The stent has also been shown to have improved biomechanical performance compared to straight stents that reduces vascular irritation and injury and the risk of stent fracture.

The MIMICs Clinical program now includes more than 1750 patients across six trials, noted Dr. Lichtenberg.

The already completed MIMICS Randomized Controlled Trial included 76 patients at 8 investigational sites and compared the safety and effectiveness of the BioMimics 3D stent (n=50) to a straight nitinol control stent (n=26). Two-year results were published by Zeller et al in Circulation: Cardiovascular Interventions in 2016.

The proportion of patients treated with the helical stent who maintained patency at 12 and 24 months was 80% and 72%, respectively, compared with 71% and 55% for the control group. The difference was significant through 24 months (p=0.05).

Freedom from clinically-driven target lesion revascularization (CDTLR) for the BioMimics stent compared to the control stent was 91% and 92%, respectively, at 12 months. However, from 12 to 24 months there were no additional cases of CDTLR in the BioMimics arm, while the number of cases with the control straight stent increased threefold (log-rank test p=0.03).

“So the principal of swirling flow seems to be more effective in terms of preventing restenosis,” said Dr. Lichtenberg.

The subsequent MIMICS-2 IDE Study, showed a 73% 12-month primary patency rate for the stent and a 3-year CDTLR rate of 81%.

The MIMICS-3D Registry is a prospective, multicenter, observational study evaluating the safety and efficacy of the BioMIMICS-3D stent in real-world patients with peripheral artery disease. Technical success in the 507 enrolled patients was 99%. Procedural success was seen in 97%, and the primary endpoint—30-day freedom from major adverse events was seen in 99%, reported Dr. Lichtenberg.

Twelve-month effectiveness was demonstrated with an 89% freedom from CDTLR.

Just over half (57.3%) of the 507 patients enrolled in the registry were Rutherford category 3, with an additional 24% being Rutherford 4-6. More than one-third (36.9%), noted Dr. Lichtenberg, were diabetic.

Moderate to severe calcification was seen in 38% of lesions. As an “all comers” registry, he noted, in 50% of patients, a drug-coated balloon was used before or after stent implantation.

Kaplan-Meier CDTLR at 1 year was 91%, falling to 83% at 2 years. “The trial will follow the patients up to three years, so hopefully we will have 3-year data next year…but I think an 83% 2-year freedom from clinically-driven TLR is a very good outcome for this patient cohort,” said Lichtenberg.

These results are comparable to drug-eluting stents, with no apparent benefit seen from the addition of paclitaxel, Lichtenberg added, and provide data supporting the therapeutic value of swirling flow.