Comparison of pharmacokinetics of the limus-eluting stents in Japanese patients.

OBJECTIVES The aim of this study was to compare the pharmacokinetics of the four limus-eluting stents used in Japanese patients. BACKGROUND There are presently no reports comparing human pharmacokinetics among drug-eluting stents (DESs). METHODS We retrospectively analyzed data from pharmacokinetic studies of patients implanted with an 18-mm DES: Cypher stent (sirolimus, n = 10), Endeavor stent (zotarolimus, n = 7), Xience V stent (everolimus, n = 6), and Nobori stent (biolimus A9, n = 10), in multicenter trials of Japan. Total drug doses of the Cypher stent, Endeavor stent, Xience V stent, and Nobori stent were 150, 180, 88, and 293 μg, respectively. Drug concentrations were measured in serial whole blood samples after implantation and the pharmacokinetics were analyzed. RESULTS Mean peak drug levels were 0.86 ng mL(-1) for Cypher, 1.80 ng mL(-1) for Endeavor, 0.50 ng mL(-1) for Xience V, and 0.09 ng mL(-1) for Nobori. After adjustment for the loaded dose, mean peak drug levels of the Cypher and Xience V stents were similar (0.0057 ng mL(-1) μg(-1) each) while the Endeavor (0.0100 ng mL(-1) μg(-1)) was higher, and the Nobori (0.0003 ng mL(-1) μg(-1)) was lower, compared with the Cypher and Xience V stents. The other pharmacokinetic parameters of four DESs differed according to characteristics of the coated drug. The systemic exposure of biolimus A9 was much lower than that of the other DESs studied. CONCLUSIONS In Japanese patients, systemic exposure was low, regardless of the type of limus drug eluted from the stents; but specific pharmacokinetic activities were varied according to the drug characteristics, concentration, and DES design.