Org 25969 (sugammadex), a selective relaxant binding agent for antagonism of prolonged rocuronium-induced neuromuscular block

Abstract
Background. Org 25969 is a cyclodextrin compound designed to reverse a rocuronium-induced neuromuscular block. The aim of this study was to explore the efficacy, dose–response relation and safety of Org 25969 for reversal of a prolonged rocuronium-induced neuromuscular block. Methods. Thirty anaesthetized adult patients received rocuronium 0.6 mg kg−1 as an initial dose followed by increments to maintain a deep block at a level of 2, following at least 2 h of neuromuscular block, patients received their randomly assigned dose of 0.5, 1.0, 2.0, 4.0 or 6.0 mg kg−1 of Org 25969. Anaesthesia and neuromuscular monitoring were continued for a minimum period of 30 min after Org 25969 administration. The main end-point of the study was the time to achieve a sustained recovery of TOF ratio to 0.9. Patients were followed up for 7 days after anaesthesia. Results. The results showed a dose-related decrease in the average time taken to attain a TOF ratio of 0.9 from 6:49 (min:s) with the 0.5 mg kg−1 dose to 1:22 with the 4.0 mg kg−1 dose. Weighted non-linear regression analysis showed the fastest achievable time to TOF ratio of 0.9 to be 1:35. Org 25969 produced no major adverse effects. Conclusion. Org 25969 effectively reversed a deep and prolonged neuromuscular block induced by rocuronium. The effective reversal dose appears to be 2–4 mg kg−1.