Sugammadex is cleared rapidly and primarily unchanged via renal excretion

Sugammadex is a modified g-cyclodextrin which rapidly reverses rocuronium-and vecuronium-induced neuromuscular blockade. Previous studies suggest that sugammadex is mostly excreted unchanged via the kidneys. This single-center, open-label, non-randomized study used C-14-labeled sugammadex to further investigate the excretion, metabolic and pharmacokinetic (PK) profiles of sugammadex in six healthy male volunteers. C-14-labeled sugammadex 4 mg/kg (0.025 MBq/kg of C-14-radioactivity) was administered as a single intravenous bolus. Blood, urine, feces and exhaled air samples were collected at pre-defined intervals for assessment of sugammadex by liquid chromatography-mass spectrometry (LC-MS) and for radioactivity measurements. Adverse events were also assessed. Excretion of sugammadex was rapid with similar to 70% of the dose excreted within 6 h and similar to 90% within 24 h. Less than 0.02% of radioactivity was excreted in feces or exhaled air. Ninety-five percent of the radioactivity detected in urine could be attributed to sugammadex, as determined by LC-MS, suggesting very limited metabolism of sugammadex. LC-MS analysis of plasma samples found that sugammadex accounted for 100% of total C-14-radioactivity in the plasma. In general, PK parameters determined from radioactivity and sugammadex plasma concentrations were very similar. Any adverse events were of mild-to-moderate intensity, and judged unrelated to sugammadex. These findings demonstrate that sugammadex is cleared rapidly, almost exclusively via the kidney, with minimal or no metabolism. Copyright (C) 2011 John Wiley & Sons, Ltd.