The pharmacokinetics of Biolimus A9 after elution from the BioMatrix II stent in patients with coronary artery disease: The Stealth PK Study

Objectives This prospective, open-label multicenter study was conducted to assess the pharmacokinetics of Biolimus A9 after elution from BioMatrix II coronary stents. Recent clinical trials have demonstrated the efficacy and safety of Biolimus A9 eluted from different stent platforms. To date, the pharmacokinetics of Biolimus A9 in patients following the deployment of BioMatrix II stents has not yet been studied Methods BioMatrix II stents were implanted into 27 patients with coronary artery disease. The primary endpoints of the study were the systemic concentrations of Biolimus A9 after 28 days and 6 months as measured using a sensitive validated liquid chromatography–tandem mass spectrometry assay. Results The highest measured blood concentration at any time point was 394 pg/mL. At 28 days and 6 months following stent placement, 51.8 and 100% of patients, respectively, had Biolimus A9 concentrations <10 pg/mL. After 9 months, 100% of the patients were free of major cardiac adverse events (MACE). There was no Biolimus A9 toxicity, no cardiac or non-cardiac deaths, no myocardial infarctions, nor target vessel or target lesion revascularizations during the 9 months of follow-up. No case of acute, subacute, or late stent thrombosis was detected. Conclusions Compared to other drug-eluting stents, such as Cypher, BioMatrix II results in relatively low systemic exposure, which may be explained by the ablominal coating of the Biomatrix II stent in combination with Biolimus A9's high lipophilicity.