Background Compared with metallic drug-eluting stents, bioresorbable vascular scaffolds (BVS) offer the potential to improve long-term outcomes of percutaneous coronary intervention. Whether or not these devices are as safe and effective as drug-eluting stents within the first year after implantation is unknown.

　　Methods We did a patient-level, pooled meta-analysis of four randomised trials in which 3389 patients with stable coronary artery disease or a stabilised acute coronary syndrome were enrolled at 301 academic and medical centers in North America, Europe, and the Asia-Pacific region. These patients were randomly assigned to the everolimus-eluting Absorb BVS (n=2164) or the Xience cobalt-chromium everolimus-eluting stent (CoCr-EES; n=1225). The primary endpoints were the 1-year relative rates of the patient-oriented composite endpoint (all-cause mortality, all myocardial infarction, or all revascularisation) and the device-oriented composite endpoint of target lesion failure (cardiac mortality, target vessel-related myocardial infarction, or ischaemia-driven target lesion revascularisation). All analyses were by intention to treat. The four randomised trials included in our meta-analysis are all registered with ClinicalTrials.gov, numbers NCT01751906, NCT01844284, NCT01923740, and NCT01425281.

　　Findings The summary treatment effect for the 1-year relative rates of the patient-oriented composite endpoint did not differ significantly different between BVS and CoCr-EES (relative risk [RR] 1.09 [0.89–1.34], p=0.38). Similarly, the 1-year relative rates of the device-oriented composite endpoint did not differ between the groups (RR 1.22 [95% CI 0.91–1.64], p=0.17). Target vessel-related myocardial infarction was increased with BVS compared with CoCr-EES(RR 1.45 [95% CI 1.02–2.07], p=0.04), due in part to non-significant increases in peri-procedural myocardial infarction and device thrombosis with BVS (RR 2.09 [0.92–4.75], p=0.08). The relative rates of all-cause and cardiacmortality, all myocardial infarction, ischaemia-driven target lesion revascularisation, and all revascularisation did not differ between BVS and CoCr-EES. Results were similar after multivariable adjustment for baseline imbalances, and were consistent across most subgroups and in sensitivity analysis when two additional randomised trials with less than 1 year of follow-up were included. Interpretation In this meta-analysis, BVS did not lead to different rates of composite patient-oriented and device-oriented adverse events at 1-year follow-up compared with CoCr-EES.