title: Advancing novel anesthetics: pharmacodynamic and pharmacokinetic studies of cyclopropyl-methoxycarbonyl metomidate in dogs.
abstract: BACKGROUND
  Cyclopropyl-methoxycarbonyl metomidate (CPMM, also known as ABP-700) is a second-generation "soft" (i.e., metabolically labile) etomidate analogue. The purpose of this study was to characterize CPMM's pharmacology in beagle dogs in preparation for potential first in human phase 1 clinical trials.
  
  
  METHODS
  CPMM's and etomidate's hypnotic activity and duration of action were assessed using loss of righting reflex and anesthesia score assays in three or four dogs. Their pharmacokinetics were defined after single bolus administration and single bolus followed by 2-h infusion. Adrenocortical recovery times after single bolus followed by 2-h infusion of CPMM, propofol, etomidate, and vehicle were measured using an adrenocorticotropic hormone stimulation test.
  
  
  RESULTS
  Compared with etomidate, CPMM was half as potent as a hypnotic (ED50 approximately 0.8 mg/kg), was more rapidly metabolized, and had a shorter duration of sedative-hypnotic action. Recovery times after CPMM administration were also independent of infusion duration. After hypnotic infusion, adrenocorticotropic hormone-stimulated plasma cortisol concentrations were 4- to 27-fold higher in dogs that received CPMM versus etomidate. Adrenocortical recovery was faster in dogs after CPMM infusion versus etomidate infusion (half-time: 215 vs. 1,623 min, respectively). Adrenocortical responsiveness assessed 90 min after CPMM infusion was not significantly different from that after propofol infusion.
  
  
  CONCLUSIONS
  The studies in dogs confirm that CPMM has hypnotic and adrenocortical recovery profiles that are superior than those of etomidate, supporting the continued development of CPMM as a clinical sedative-hypnotic to be used as a single bolus and by continuous infusion to induce and maintain general anesthesia or procedural sedation.
authors.affiliation: From the Medicines Company, Inc., Parsippany, New Jersey (J.A.C.); Annovation BioPharma, Inc., Cambridge, Massachusetts (K.P., D.G., J.R.); and Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts (D.E.R.).
authors.forename: Jason A
authors.initials: JA
authors.lastname: Campagna
authors.forename: Kevin
authors.initials: K
authors.lastname: Pojasek
authors.forename: David
authors.initials: D
authors.lastname: Grayzel
authors.forename: John
authors.initials: J
authors.lastname: Randle
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Raines
mesh_terms: D000302:Adrenal Cortex / Q000187:drug effects; D000758:Anesthesia; D018686:Anesthetics, Intravenous / Q000493:pharmacokinetics* / Q000494:pharmacology*; D000818:Animals; D019540:Area Under Curve; D001522:Behavior, Animal / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D004285:Dogs; D005045:Etomidate / Q000031:analogs & derivatives* / Q000493:pharmacokinetics* / Q000494:pharmacology*; D006993:Hypnotics and Sedatives / Q000493:pharmacokinetics* / Q000494:pharmacology*; D008297:Male; D015233:Models, Statistical; D015742:Propofol / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D018686:Anesthetics, Intravenous; D006993:Hypnotics and Sedatives; D015742:Propofol; C084586:metomidate; D005045:Etomidate