BIOFLOW-IV, a randomised, intercontinental, multicentre study to assess the safety and effectiveness of the Orsiro sirolimus-eluting stent in the treatment of subjects with de novo coronary artery lesions: primary outcome target vessel failure at 12 months.

The BIOFLOW-IV clinical trial was designed for regulatory submission in Japan. It assessed the safety and efficacy of a new third-generation sirolimus-eluting stent system with bioresorbable polymer (Orsiro, BP-SES) compared with an everolimus-eluting stent system with permanent polymer (XIENCE Prime/Xpedition, PP-EES). This prospective, international, multicentre, 2:1 randomised, non-inferiority trial enrolled 575 patients (385 BP-SES and 190 PP-EES) with 659 stenotic de novo lesions. Of these, 137 patients (23.8%) were Japanese. Follow-up until five years is ongoing. We herein report outcomes at 12 months. Baseline parameters were well balanced. Device success was 98.9% for BP-SES versus 99.6% for PP-EES, p=0.670. Non-inferiority related to 12-month target vessel failure was met (pnon-inferiority <0.001). Further, there was no significant difference in clinical outcomes between the groups. The target vessel failure rate was 5.5% for BP-SES and 7.5% for PP-EES, the target lesion failure rate was 4.2% versus 5.4%, and the definite or probable stent thrombosis rate was 0.8% versus 0%. The randomised BIOFLOW-IV trial provides further evidence on the safety and efficacy of the Orsiro BP-SES and its non-inferiority to the current benchmark, an everolimus-eluting permanent polymer stent. ClinicalTrials.gov: NCT01939249.