Efficacy and safety of ciprofol versus propofol for the induction of anesthesia in adult patients: a multicenter phase 2a clinical trial

Background Ciprofol is a novel 2, 6-disubstituted phenolic derivative anesthetic that binds to the gamma-aminobutyric acid-A receptor. Aim To determine the equally potent dose of ciprofol compared with propofol as an induction agent for general anesthesia in patients undergoing selective surgery, and to assess its safety. Method A total of 109 patients undergoing selective non-emergency, non-cardiothoracic or non-neurosurgical surgery requiring tracheal intubation for general anesthesia were enrolled. Ten patients per group were assigned to ciprofol-0.3, 0.4 and 0.5 mg/kg, and propofol-2.0 or 2.5 mg/kg groups, respectively to receive an intravenous bolus dose. An additional 20 patients were enrolled in the ciprofol-0.3, 0.5 or propofol-2.0 mg/kg groups. The primary outcome was the success rate of induction defined as a Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) ≤ 1 after the initial bolus dose. The secondary outcomes included the time to reach MOAA/S ≤ 1, the time to loss of the eyelash reflex, the incidences and severity of adverse events (AEs). Results The success rates were 100% for all 5 groups. The mean time to MOAA/S ≤ 1 and the time to loss of the eyelash reflex were not different among the 5 groups, regardless of whether a top-up dose was needed. There were no significant differences in the incidences and severity of AEs in the dose ranges investigated of ciprofol vs. propofol. Conclusion The efficacy and safety of a single bolus dose of ciprofol-0.5 mg/kg for the general anesthesia induction in selective surgery patients was comparable to that of propofol-2.0 mg/kg. Trial registration Clinicaltrials.gov, NCT03698617, retrospectively registered.