Results of the HOST-REDUCE-POLYTECH-ACS, presented at TCT Connect 2020 (14–18 October, virtual) suggest that drug-eluting stents (DES) with durable polymers are non-inferior to DES with biodegradable polymers in patients with acute coronary syndrome (ACS). The findings were presented during a late breaking trial session at TCT Connect 2020 by Hyo-Soo Kim, director, Coronary Intervention and Transcatheter Aortic Valve Implantation (TAVI), and professor, Department of Internal Medicine at Seoul National University Hospital, Seoul, Korea.
Newer drug-eluting stents (DES) have significantly improved outcomes among patients undergoing percutaneous coronary intervention (PCI) Kim’s presentation suggested, but noted that the polymers used in first-generation DESs were blamed as the cause of a chronic inflammatory response that leads to stent-oriented adverse clinical outcomes, such as stent thrombosis. Biocompatible durable polymers and biodegradable polymers were developed to help mitigate this adverse effect.
The comparison of these two polymer technologies in patients with ACS, who have a heightened risk of thrombosis and delayed vascular healing after PCI, has not been previously examined in a large-scale randomised trial. The aim of the trial was to investigate the efficacy and safety of a durable polymer DES versus a biodegradable polymer DES in patients with ACS undergoing PCI. Patients with a culprit lesion in a native coronary artery or a graft vessel with significant stenosis eligible for stent implantation were randomized in a 1:1 fashion to durable polymer or biodegradable polymer DES.
The primary endpoint was a patient-oriented composite outcome (POCO), defined as a composite of all-cause death, nonfatal myocardial infarction, stent thrombosis, and any repeat revascularisation, at 12 months. The key secondary endpoint was a device-oriented composite endpoint (DOCO), a composite of cardiac death, target vessel myocardial infarction, or target lesion revascularisation.
From August 2015 to December 2018, a total of 3,413 ACS patients with 4,713 lesions were enrolled from 35 centres and were randomised to the durable polymer DES group (1,713 patients, 2,367 lesions) or the absorbable polymer DES group (1,700 patients, 2,346 lesions). Durable polymer DES included the Promus Premier (Boston Scientific) (953 lesions, 40.3%), Resolute Onyx (Medtronic) (712 lesions, 30.1%), Xience Alpine (Abbott) (687 lesions, 29.0%), and DESyne (Elixir Medical) (29 lesions, 1.2%) stents.
Absorbable polymer DESs included the Ultimaster (Terumo) (748 lesions. 31.9%), Orsiro (Biotronik) (598 lesions, 25.5%), Biomatrix Flex (Biosensors) (508 lesions, 21.7%), Nobori (Terumo) (219 lesions, 9.3%), Synergy (Boston Scientific) (150 lesions, 6.4%), and Biomatrix (Biosensors) (98 lesions,4.2%) stents. The mean age of patients was 63 years. ST segment elevation myocardial infarction was in 13.2% and diabetes was in 45.0%. Also, 54.4% of the population had multivessel coronary artery disease, and 30.5% received multivessel intervention. The target lesion was located in the left anterior descending artery in 50.3%, at a bifurcation in 21.8%, and were ACC/AHA type B2/C lesions in 55.0%.
Intravascular ultrasound was used in 33.4% and the number of stents implanted per patient was 1.7±1.0. The trial has completed follow-up up to one year post-PCI, with accrual of the target number of primary endpoints (n=193).
The rate of POCO was 5.2% in the durable polymer DES compared to 6.4% in the biodegradable polymer DES group (HR 0.81, 95% CI 0.61-1.08, p=0.146). The rate of DOCO was slightly higher in the biodegradable polymer group (2.6% vs. 3.9% HR 0.67, 95% CI 0.46-0.98, p=0.038).
“In ACS patients who had a significant coronary stenosis and were eligible for stent implantation, durable polymer DES was non-inferior to biodegradable polymer DES, in terms of one-year patient oriented composite outcomes,” said Kim. “Regarding the device oriented composite outcome, we observed a sign of higher clinical events in the biodegradable polymer DES. More research is needed to assess the effect of polymer technology on clinical outcomes greater than one-year post PCI.”
The HOST-REDUCE-POLYTECH-ACS trial was sponsored by Seoul National University Hospital and received research funds from Biotronik, Boston Scientific, Daiichi Sankyo, Dio, Qualitech Korea Ltd., and Terumo.