Remimazolam, a short-acting GABA_A receptor agonist for intravenous sedation and/or anesthesia in day-case surgical and non-surgical procedures

Remimazolam (CNS-7056) is a short-acting GABAA receptor agonist, under development by PAION, in collaboration with Japanese licensee Ono Pharmaceutical, as an intravenous sedative agent for potential use in day-case procedures, and the induction and maintenance of anesthesia. A member of the benzodiazapene class of drugs, the structure of remimazolam was modified to produce a drug that displays organ-independent metabolism. The incorporation of a carboxylic ester moiety into the benzodiazapene core of remimazolam renders it susceptible to non-specific tissue esterases and it is rapidly metabolized into its pharmacologically inactive metabolite CNS-7054. Preclinical studies in sheep demonstrated that remimazolam produced a more rapid onset of action, and a shorter duration of action, compared with midazolam. In a phase IIa clinical trial evaluating remimazolam as a procedural sedative for upper gastrointestinal endoscopy in patients, the time to recovery from sedation was shorter and more consistent with remimazolam, relative to midazolam. Because of its organ-independent metabolism and rapid and predictable onset and recovery, remimazolam appears to have potential advantages over other currently available short-acting sedatives.