Three-Year Data Presented for Subgroup Analysis of Small Vessels in Biotronik's BIO-RESORT Trial
May 21, 2019—Biotronik announced the presentation of 3-year outcomes in a subgroup of patients with small vessels in the BIO-RESORT randomized controlled trial by Principal Investigator Clemens von Birgelen, MD, at EuroPCR held May 21–24 in Paris, France.
The data showed a significantly lower target lesion revascularization (TLR) rate and, thus, better efficacy of the company's Orsiro drug-eluting stent (DES) in comparison to the Resolute Integrity DES (Medtronic). The study was simultaneously published by Rosaly A. Buiten, MD, et al online ahead of print in Journal of the American Medical Association: Cardiology.
The background of the analysis is that the large-scale, multicenter BIO-RESORT trial has a full cohort of 3,514 patients undergoing percutaneous coronary intervention, of whom 42.9% presented with the need for small vessel treatment. The company noted that although stenting of small coronary vessels is common, these patients are exposed to subsequent increased adverse cardiovascular event risks.
According to Biotronik, the large all-comers BIO-RESORT trial included 1,506 patients with small coronary vessels who were treated with the Orsiro sirolimus-eluting stent, Resolute Integrity zotarolimus-eluting stent, or Synergy everolimus-eluting stent (Boston Scientific Corporation). The 3-year results showed a target lesion failure rate for Orsiro of 7% compared to 10% for Resolute Integrity and 9.5% for Synergy (Orsiro vs Resolute Integrity, P = .08; Synergy vs Resolute Integrity, P = .72).
The three stents showed similar results in terms of cardiac death and myocardial infarction. However, patients treated with the ultrathin-strut Orsiro stent experienced significantly fewer repeat TLRs than patients treated with the thin-strut Resolute Integrity stent (2.1% vs 5.3%, respectively; P = .009; Synergy, 4%).
Biotronik noted that the divergence seemed more pronounced after the first year after the index procedure when dual antiplatelet therapy was stopped. This is supported in a TLR landmark analysis between 1 and 3 years, where the TLR rate was 1% with Orsiro, 3.7% with Resolute Integrity (P = .006), and 2.7% with Synergy. Additionally, Orsiro showed a trend toward a lower rate of definite or probable stent thrombosis with a rate of 0.6% compared to 1.5% for Resolute Integrity (P = .16) and 1.5% for Synergy.
In the company's announcement, Prof. Clemens von Birgelen commented, “The results may be clinically relevant, as they suggest a relation between the use of ultrathin-strut sirolimus-eluting stents and a lower repeat revascularization risk in all-comers patients with small target vessels. Due to a greater relative impact of stent strut size on lumen obstruction, the substantially thinner struts of these new-generation DESs may be particularly advantageous in small vessels.”