Four-year results from the LEADERS trial show that BioMatrix Flex, Biosensors’ Biolimus A9-eluting stent system with a biodegradable polymer coating, significantly reduces the risk of very late stent thrombosis compared to that of a drug-eluting stent system with a durable polymer coating.
This reduced risk of very late stent thrombosis is positively associated with a reduced risk of cardiac events, therefore demonstrating for the first time ‘proof of concept’ that a drug-eluting stent with biodegradable polymer improves long-term clinical outcomes compared to a drug-eluting stent with durable polymer. These results were published in the latest issue of The Lancet.
“This study shows that the problem of very late stent thrombosis, which was prevalent with first-generation durable-polymer drug-eluting stents, is markedly reduced by a stent using a biodegradable polymer,” commented Stephan Windecker, principal investigator, University Hospital, Bern, Switzerland. “This translates into a late benefit in terms of cardiac death or myocardial infarction.”
The LEADERS study is a head-to-head randomised trial between two limus-eluting stents, BioMatrix Flex and Cypher Select, Johnson & Johnson’s sirolimus-eluting stent system with a durable polymer. The study involves an “all-comers” patient population and measures clinical outcomes. The primary endpoint from LEADERS, published in The Lancet in 2008, demonstrated BioMatrix Flex to be non-inferior to Cypher Select with respect to the primary endpoint, incidence of MACE (a composite of cardiac death, myocardial infarction, or clinically-indicated target vessel revascularisation) at nine months. This non-inferiority has been confirmed in the one, two, three and four-year results, during which time a diverging trend towards a safety benefit for BioMatrix Flex was observed.
At four years, the risk of MACE was lower in patients treated with BioMatrix Flex than in those treated with Cypher Select (18.7% vs. 22.6%: p = 0.050, 96% of patients followed-up). The benefit of BioMatrix Flex appeared more pronounced between years one and four. During this one to four year period, BioMatrix Flex was associated with a significant 80% relative risk reduction in definite very late stent thrombosis compared with Cypher Select (p=0.004).
An analysis of the correlation between MACE and definite stent thrombosis events showed that the benefit in favor of BioMatrix Flex in terms of MACE was largely driven by a lower risk of MACE associated with definite very late stent thrombosis.
“We are very encouraged by these results, which further support the long-term patient benefit of BioMatrix Flex”, added Jeffrey B Jump, co-CEO of Biosensors. “LEADERS shows that improvement in drug-eluting stent technology directly translates into improved patient safety”.