The Synergy Everolimus-Eluting Bioabsorbable Polymer-Coated Platinum Chromium Coronary Stent System demonstrated non-inferior results in treating de novo coronary artery lesions at one year compared to the Promus Element Everolimus-Eluting Platinum Chromium Stent System (both stents systems from Boston Scienfic), according to results from the EVOLVE first human use trial. Data were presented by Stefan Verheye, senior interventional cardiologist at the Antwerp Cardiovascular Institute, ZNA Middelheim Hospital, Belgium, at EuroPCR.
EVOLVE is a prospective, randomised, single-blind, study evaluating the non-inferiority of the Synergy stent, which employs an ultra-thin bioabsorbable polymer applied to the outer (abluminal) surface of the stent, compared to the Promus Element stent, which utilises a permanent durable polymer applied to the entire stent (conformal) surface. The study randomised 291 patients to one of three arms: the full-dose Synergy stent (with the Promus Element dose of everolimus), half-dose Synergy stent (half the everolimus dose of Promus Element), or the commercially available Promus Element stent. All three stents employ a similar drug release profile.
The EVOLVE trial previously reported the primary angiographic and clinical endpoints of non-inferiority of the Synergy stent compared with Promus Element for late loss at six months and target lesion failure (TLF) at 30 days. The EVOLVE one-year trial data demonstrated that both versions of the Synergy stent (loaded with both full- and half-dose everolimus) are clinically non-inferior to the Promus Element stent. There were no significant differences between groups for all IVUS parameters evaluated at six months, including neointimal area, stent or lumen area, net volume obstruction, incomplete stent apposition or minimum lumen diameter.
“The 6-month IVUS data suggest that anti-restenotic activity is maintained with the Synergy stent, even after four months, when the drug and polymer coating are designed to be absorbed. Importantly, the Synergy stent has shown equivalent clinical safety and effectiveness in the EVOLVE data compared to the Promus Element stent. We continue to observe very low rates of revascularisation and no cardiac-related deaths or stent thrombosis with Synergy at one year,” said Verheye. “The EVOLVE data demonstrate the effectiveness of drug elution from an ultra-thin, abluminal bioabsorbable polymer with this innovative coronary stent platform.”
At one year, TLF in both study arms was not statistically different from the Promus Element stent (4.4%, 4.2% and 5.1% for the full-dose Synergy stent, half-dose Synergy stent and Promus Element stent, respectively; p=1.00 for superiority comparison of each Synergy stent version with the Promus Element stent). TLF is defined as target-vessel-related cardiac death, target-vessel-related myocardial infarction, or ischaemia-driven target lesion revascularisation (TLR).
Clinical follow-up at one year demonstrated no cardiac related deaths, Q-wave myocardial infarction, or stent thrombosis for any of the stent groups. Periprocedural non-Q-wave myocardial infractions had previously been observed in one patient in the full-dose Synergy arm and three patients in the half-dose Synergy arm; an additional two non-Q-wave myocardial infarctions occurred between 6 and 12 months in the full-dose Synergy arm; however, these were not considered related to the stent. Non-Q-wave myocardial infarction rates were not significantly different between groups at any time point up to and including one year (3.3% for full-dose Synergy [p=0.11], 3.2% for half-dose Synergy [p=0.12], each compared to 0.0% for Promus Element). TLR was 1.1% for both Synergy doses versus 5.1% for Promus Element (p=0.21). Additionally, target vessel revascularisation (TVR) was noted to be numerically lower with the Synergy stent, but the difference was not statistically significant (3.3% for full-dose Synergy [p=0.09] and 4.2% for half-dose Synergy [p=0.17] each compared to 9.2% for Promus Element).
“The Synergy stent is a next-generation everolimus-eluting stent that combines the same platinum chromium alloy and similar design used in the Promus Element stent with a novel coating created to significantly reduce the amount of polymer and drug to which the blood vessel wall is exposed, without compromising inhibition of neointimal growth,” said Keith D Dawkins, global chief medical officer, Boston Scientific. “Synergy is designed to address potential limitations with durable polymer coatings used on currently available drug-eluting stents, including issues with dual antiplatelet therapy interruption and duration. We continue to be pleased with the impressive clinical and angiographic results from the EVOLVE trial for this advanced coronary stent technology.”
EVOLVE trial data are expected to support CE mark approval for the Synergy stent, which is expected as early as later this year, while additional larger studies are anticipated to further assess clinical event rates and the potential for reduced dual antiplatelet therapy with this novel stent technology.
The Synergy stent is an investigational device, limited by applicable law to investigational use only and not available for sale.