Efficacy and safety of remimazolam besylate in patients receiving mechanical ventilation: A randomized phase Ⅱa trial

To preliminarily evaluate the efficacy, safety and continuous infusion dose of remimazolam besylate in short-term mechanically ventilated patients in intensive care units. This randomized phase Ⅱa trial was conducted in intensive care units (ICUs) in six hospitals in China. Adults that were anticipated to receive mechanical ventilation for ≥6 h and to have a Richmond Agitation–Sedation Scale (RASS) scores of -2 to +1 were enrolled in the trial and randomized (1:1:1) into three groups to receive 0.1, 0.2, or 0.4 mg/(kg•h) remimazolam besylate. The primary outcome was the percentage of time with the target RASS scores without rescue sedation. The secondary endpoint was adverse drug reactions (ADRs). The optimal continuous infusion dose was also explored. The percentage of time with the target RASS scores without rescue sedation did not differ among the groups (97.5±6.0 in the 0.1 mg/(kg•h) group with 11 participants, 95.2±8.0 in the 0.2 mg/(kg•h) group with 12 participants, and 97.0±2.4 in the 0.4 mg/(kg•h) group with 11 participants; P =0.665). The numbers of patients with ADRs were 7 (63.6%), 4 (33.3%), and 6 (54.5%) in the 0.1, 0.2, and 0.4 mg/(kg•h) groups, respectively ( P =0.326). No participants experienced severe ADRs, and only 1 (9.1%) in the 0.4 mg/(kg•h) group experienced a grade 3–5 ADR. The optimal continuous infusion dose was 0.2–0.3 mg/(kg•h). Remimazolam besylate seems efficacious and safe in patients receiving short-term mechanical ventilation and light sedation, which justifies further trials. Trial Registration Clinicaltrials.gov Identifier: NCT06124404.