First-in-human evaluation of a novel ultrathin sirolimus-eluting iron bioresorbable scaffold: 3-year outcomes of the IBS-FIM trial.

Background: The first-generation polymeric bioresorbable scaffolds resulted in higher than acceptable 3-year rates of device-related adverse outcomes.

Aims: We aimed to assess the intermediate-term safety and performance of a novel ultrathin-strut sirolimus-eluting iron bioresorbable scaffold (IBS) in non-complex coronary lesions.

Methods: The prospective, single-arm, open-label IBS first-in-human study enrolled 45 patients, each with a single de novo lesion. Enrolled patients were randomly assigned to 2 follow-up cohorts. Angiographic and imaging follow-up with intravascular ultrasound and optical coherence tomography (OCT) were conducted at 6 and 24 months in cohort 1 (n=30) and at 12 and 36 months in cohort 2 (n=15). Clinical follow-up was conducted at 1, 6 and 12 months, and annually thereafter up to 5 years. The coprimary outcomes were target lesion failure (TLF) and angiographic late lumen loss (LLL) at 6 months.

Results: A total of 45 patients were enrolled between April 2018 and January 2019. The mean age was 53.2 years, 77.8% were male, and 26.7% had diabetes. The TLF rates were 2.2% at 6 months and 6.7% at 3 years, which in all cases were due to clinically indicated target lesion revascularisation. No deaths, myocardial infarctions or stent thromboses occurred during 3-year follow-up. In-scaffold LLL was 0.33±0.27 mm at 6 months and 0.37±0.57 mm at 3 years. By OCT, the proportion of covered struts was 99.8% at 6 months and 100% after 1 year. The 3-year strut absorption rate was 95.4%.

Conclusions: In this first-in-human experience, an ultrathin IBS was safe and effective for the treatment of de novo non-complex coronary lesions up to 3-year follow-up.