The pharmacokinetics of Biolimus A9 after elution from the Nobori stent in patients with coronary artery disease: the NOBORI PK study.

Objectives: The aim of this study was to assess the pharmacokinetics and tolerability of Biolimus A9 eluted from Nobori coronary stents.

Background: : The release kinetics and pharmacokinetics of drugs delivered via coronary stents have been shown to play an essential role in the efficacy and safety of drug eluting stents.

Methods: Twenty patients with coronary artery disease were treated with single 14-mm (10 patients) or 28-mm long stent (10 patients). Blood samples were drawn at 16 time points to determine the pharmacokinetics of Biolimus A9. At seven time points, complete laboratory and toxicology panels were assessed to screen for potential Biolimus A9 toxicity. The primary endpoint of the study was the systemic blood concentrations of Biolimus A9 after 28 days and 6 months as measured using highly specific and sensitive liquid chromatography- tandem mass spectrometry assay.

Results: At 28 days, 6 patients (30%) had quantifiable Biolimus A9 concentrations in blood. The highest Biolimus A9 blood concentration measured in any sample was 32.2 pg/mL. The median time to maximum concentration was 2 hr, ranging from 0.05 hr to 3 months. Six months after stent implantation, only 1 of 20 patients had measurable Biolimus A9 concentrations at the lowest level of quantification, while at 9 months no sample had quantifiable Biolimus A9 concentrations. Laboratory and toxicology assessments did not indicate any impact of Biolimus A9 on the evaluated parameters.

Conclusion: Results of this study suggest that systemic exposure to Biolimus A9 was very low and that Biolimus A9 was well tolerated.