Three-year outcome data from the BIO-RESORT randomised controlled trial, which were presented at the 2019 Cardiovascular Research Technologies (CRT) meeting (2–5 March, Washington, DC, USA), confirmed the trend of earlier data supporting the use of the ultrathin biodegradable polymer drug-eluting stent Orsiro (Biotronik). The study reviewed outcomes of Orsiro vs. those for Resolute Integrity (Medtronic) and Synergy (Boston Scientific) in a complex all-comers population.
At the three-year follow-up in the BIORESORT trial, with a cohort of 3,514 patients, all three stents showed low target vessel failure rates. Orsiro demonstrated favourable outcomes without reaching statistical significance (Orsiro 8.5%, Synergy 8.8%, Resolute Integrity 10.0%). The same tendency was observed for target lesion revascularisation where Orsiro demonstrated numerically lower values in comparison to Resolute Integrity and Synergy (Orsiro 2.9%, Synergy 3.3%, Resolute Integrity 3.8%).
Furthermore, in a separate meta-analysis, Orsiro was associated with a significant reduction in myocardial infarction compared with Xience. At CRT, Thomas Pilgrim (University of Bern, Switzerland) presented the results of a patient-level meta-analysis from four randomised controlled trials comparing the safety and efficacy of Orsiro to Xience. From the pool of 4,480 patients from BIOFLOW-II, -IV, and -V, as well as BIOSCIENCE, 2,630 patients were treated with Orsiro and 1,850 with Xience. The primary endpoint was target lesion failure at maximum duration of follow-up.
For the primary endpoint, Orsiro demonstrated a favourable trend without reaching statistical significance in comparison to Xience (11.9% vs. 14.5% respectively). No differences between Orsiro and Xience were seen in the individual components of target lesion failure: cardiac death occurred in 3.5% vs. 4.5% of the patients, target-vessel myocardial infarction in 5% vs. 6.5% and clinically-driven target lesion revascularisation in 5.9% vs. 7.0% for Orsiro and Xience, respectively. While the safety endpoint of definite or probable stent thrombosis did not show a statistical difference between Orsiro and Xience, (2.7% vs. 4.5% respectively), a statistically significant reduction in the risk of any myocardial infarction among patients undergoing PCI with Orsiro in comparison to Xience was observed (7.1% vs. 9.6%, p=0.03).
Additionally, Soeren Mattke (University of Southern California, Los Angeles, USA) presented results from the health economic evaluation based on the two-year results of the BIOFLOW-V clinical trial. The evaluation used a Markov simulation to project the mortality and cost outcomes from a US health systems perspective over a horizon of four years and builds on work published in 2018. The findings suggest that the use of the Orsiro stent is associated with a meaningful reduction in direct medical costs and improved patient outcomes compared to the Xience stent. The study estimated cost savings of US$2,429 per patient over four years, assuming the two stents were priced at parity. Around two-thirds of the savings were due to the lower rate of spontaneous target vessel myocardial infarction in the first two years after stent implantation.
The lower rate of adverse events for the Orsiro stent in the BIOFLOW-V trial is projected to reduce mortality risk by 6% over four years after stent implantation compared to the Xience stent. Mattke comments: “Those results may help clinicians, payers and purchasers to make decisions about the choice of coronary stents, as they suggest that the use of the Orsiro stent can simultaneously reduce medical costs and improve patient outcomes. For a high volume procedure like coronary stenting, these differences have meaningful implications for population health and financial sustainability of healthcare systems.”