Randomised evaluation of a novel biodegradable polymer-based sirolimus-eluting stent in ST-segment elevation myocardial infarction: the MASTER study

Aims: The MASTER study was designed to compare the performance of a new biodegradable polymer sirolimus-eluting stent (BP-SES) with a bare metal stent (BMS) in patients with ST-segment elevation myocardial infarction (STEMI). Methods and results: The study was a prospective, randomised (3:1), controlled, single-blind multicentre trial that enrolled 500 STEMI patients within 24 hours of symptom onset during 2013-2015. Three hundred and seventy-five patients were treated with BP-SES and 125 with BMS. One hundred and four (104) randomised patients underwent angiographic follow-up at six months. The primary clinical endpoint was target vessel failure (TVF), defined as cardiac death, MI not clearly attributable to a non-target vessel, or clinically driven target vessel revascularisation (TVR) at 12 months. The primary angiographic endpoint was in-stent late lumen loss (LLL) at six months in the angiographic cohort. The major secondary endpoint for safety was a composite of all-cause death, recurrent MI, unplanned infarct-related artery revascularisation, stroke, definite stent thrombosis (ST) or major bleeding at one month. At 12 months, TVF had occurred in 6.1% of BP-SES and 14.4% of BMS patients (p(non-inferiority)=0.0004), mainly driven by a higher rate of repeat revascularisation in BMS patients. The safety endpoint occurred in 3.5% of BP-SES and 7.2% of BMS patients (p=0.127). In-stent LLL demonstrated the superiority (p=0.0125) of BP-SES (0.09 +/- 0.43 mm) over BMS (0.79 +/- 0.67 mm). Conclusions: The study showed clinical non-inferiority and angiographic superiority of BP-SES versus a comparator BMS, suggesting that this novel DES may be a potential treatment option in STEMI.