Two Studies Highlight Safety, Efficacy of Biodegradable Polymer SES

Biodegradable-polymer sirolimus-eluting stents show promising safety and efficacy results compared with permanent-polymer DES, according to 2 separate presentations March 25, 2012, at the annual American College of Cardiology/i2 Scientific Session.

In the first study, Robert A. Byrne, MD, of Deutsches Herzzentrum (Munich, Germany) and colleagues pooled individual patient data from 3 large-scale multicenter randomized clinical trials (ISAR-TEST 3, ISAR-TEST 4, and LEADERS) comparing biodegradable polymer drug-eluting stents (sirolimus-eluting, n = 1,501; and biolimus-eluting, n = 857) with durable polymer sirolimus-eluting stents (n = 1,704) and assessed clinical outcomes during follow-up through 4 years.

The study was simultaneously published online in the European Heart Journal.

TLR, Stent Thrombosis and MI Lower

Overall, the risk of clinically indicated target lesion revascularization (TLR) was significantly lower at 4 years among patients treated with the biodegradable polymer DES vs. the durable polymer sirolimus-eluting stents. In addition, the risk of definite stent thrombosis at 4 years was significantly reduced with biodegradable polymer DES vs. durable polymer SES, driven by a lower risk of very late stent thrombosis. In landmark analysis between 1 and 4 years, patients treated with biodegradable polymer DES also had significantly lower risk of MI (table 1).

Table 1. Biodegradable Polymer DES vs. Durable Polymer SES

According to Dr. Byrne, the data from the combined data sets represent an important step in the proof-of-concept chain of investigation of biodegradable polymer DES.

“Furthermore, such an enhanced safety profile beyond 12 months with biodegradable polymer DES may have implications regarding the requirement for an extended duration of [dual antiplatelet therapy] following coronary stenting,” he added.

More Biodegradable Polymer DES Success

A second presentation also demonstrated comparable safety and efficacy of biodegradable polymer DES. Researchers led by Junbo Ge, MD, of Zhongshan Hospital (Shanghai, China), enrolled 1,923 patients with de novo coronary artery lesions in the EVOLUTION noninferiority trial, which was conducted at 30 centers in China from December 2008 to September 2010. Patients were randomized to treatment with either a serolimus-eluting stent with a biodegradable polymer (EXCEL, JW Medical System Ltd, Weihai, China) or a sirolimus-eluting stent with a durable polymer (Cypher Select, Cordis Corporation, Miami Lakes, FL).

At 12 months, sirolimus-eluting stents with biodegradable polymer were noninferior to durable- polymer SES for the primary endpoint of ischemia-driven target vessel failure (TVF) within 12 months (a composite of cardiac death, MI, and ischemia-driven TVR). Incidence of cardiac death, MI and clinically-indicated TVR were similar for both stent types (table 2).

Table 2. One-Year Outcomes

P for noninferiority.

Sources:

1. Ge J. Sirolimus eluting stent with biodegradable polymer versus sirolimus eluting stent with durable polymer for the treatment of patients with de novo coronary artery lesions (EVOLUTION): A randomized non-inferiority trial. Presented at: American College of Cardiology Annual Scientific Session; March 24, 2012; Chicago, IL.
2. Stefanini GG, Byrne RA, Serruys PW, et al. Biodegradable polymer drug-eluting stents reduce the risk of stent thrombosis at 4 years in patients undergoing percutaneous coronary intervention: A pooled analysis of individual patient data from the ISAR-TEST 3, ISAR-TEST 4, and LEADERS randomized trials. Eur Heart J. 2012;Epub ahead of print.

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