Efficacy and safety of remimazolam versus propofol for general anesthesia: a multicenter, single-blind, randomized, parallel-group, phase IIb/III trial.

This trial was conducted to confirm the non-inferiority of remimazolam versus propofol in the induction and maintenance of general anesthesia in surgical patients. Surgical patients (n = 375) were randomized to remimazolam started at 6 or 12 mg/kg/h by continuous intravenous (IV) infusion until the loss of consciousness (LoC), followed by 1 mg/kg/h to be adjusted as appropriate until the end of surgery or IV propofol administered as a slow bolus of 2.0-2.5 mg/kg until LoC followed by 4-10 mg/kg/h until the end of surgery. Efficacy was measured via the combined primary endpoint of no intraoperative awakening/recall, no need for rescue sedatives, and no body movements. Adverse events and adverse drug reactions (ADRs) were monitored for safety. Efficacy rates were 100% in all treatment groups, and the non-inferiority of remimazolam was demonstrated [95% confidence interval (- 0.0487; 0.0250)]. The time to LoC was longer in the remimazolam 6 (p < 0.0001) and 12 mg/kg/h (p = 0.0149) groups versus propofol. The time to extubation was longer in both remimazolam groups versus the propofol group (p ≤ 0.0001). The incidence of ADRs was similar in the remimazolam groups (39.3% and 42.7%, respectively) compared with the propofol group (61.3%). Decreased blood pressure occurred in 20.0% and 24.0% of patients treated with 6 and 12 mg/kg/h remimazolam, respectively, compared with 49.3% of patients receiving propofol. Injection site pain was reported in 18.7% of propofol patients but not in those receiving remimazolam. This trial demonstrated that remimazolam was well tolerated and non-inferior to propofol with regard to efficacy as a sedative hypnotics for general anesthesia. This trial is registered with the Japan Pharmaceutical Information Center - Clinical Trials Information (JapicCTI). JapicCTI number: 121973.