The Novel, Nicotinic Alpha7 Receptor Partial Agonist, BMS-933043, Improves Cognition and Sensory Processing in Preclinical Models of Schizophrenia

PLoS One. 2016 Jul 28;11(7):e0159996. doi: 10.1371/journal.pone.0159996. eCollection 2016.

Abstract

The development of alpha7 nicotinic acetylcholine receptor agonists is considered a promising approach for the treatment of cognitive symptoms in schizophrenia patients. In the present studies we characterized the novel agent, (2R)-N-(6-(1H-imidazol-1-yl)-4-pyrimidinyl)-4'H-spiro[4-azabicyclo[2.2.2]octane-2,5'-[1,3]oxazol]-2'-amine (BMS-933043), in vitro and in rodent models of schizophrenia-like deficits in cognition and sensory processing. BMS-933043 showed potent binding affinity to native rat (Ki = 3.3 nM) and recombinant human alpha7 nicotinic acetylcholine receptors (Ki = 8.1 nM) and agonist activity in a calcium fluorescence assay (EC50 = 23.4 nM) and whole cell voltage clamp electrophysiology (EC50 = 0.14 micromolar (rat) and 0.29 micromolar (human)). BMS-933043 exhibited a partial agonist profile relative to acetylcholine; the relative efficacy for net charge crossing the cell membrane was 67% and 78% at rat and human alpha7 nicotinic acetylcholine receptors respectively. BMS-933043 showed no agonist or antagonist activity at other nicotinic acetylcholine receptor subtypes and was at least 300 fold weaker at binding to and antagonizing human 5-HT3A receptors (Ki = 2,451 nM; IC50 = 8,066 nM). BMS-933043 treatment i) improved 24 hour novel object recognition memory in mice (0.1-10 mg/kg, sc), ii) reversed MK-801-induced deficits in Y maze performance in mice (1-10 mg/kg, sc) and set shift performance in rats (1-10 mg/kg, po) and iii) reduced the number of trials required to complete the extradimensional shift discrimination in neonatal PCP treated rats performing the intra-dimensional/extradimensional set shifting task (0.1-3 mg/kg, po). BMS-933043 also improved auditory gating (0.56-3 mg/kg, sc) and mismatch negativity (0.03-3 mg/kg, sc) in rats treated with S(+)ketamine or neonatal phencyclidine respectively. Given this favorable preclinical profile BMS-933043 was selected for further development to support clinical evaluation in humans.

MeSH terms

  • Animals
  • Cognition Disorders / drug therapy*
  • Cognition Disorders / physiopathology
  • Drug Evaluation, Preclinical
  • HEK293 Cells
  • Humans
  • Male
  • Mice
  • Patch-Clamp Techniques
  • Quinuclidines / pharmacology
  • Quinuclidines / therapeutic use*
  • Radioligand Assay
  • Rats
  • Schizophrenia / drug therapy*
  • Schizophrenia / physiopathology
  • Spiro Compounds / pharmacology
  • Spiro Compounds / therapeutic use*
  • alpha7 Nicotinic Acetylcholine Receptor / agonists*

Substances

  • BMS-933043
  • Quinuclidines
  • Spiro Compounds
  • alpha7 Nicotinic Acetylcholine Receptor

Grants and funding

This work was funded by Bristol-Myers Squibb Company and all authors were paid employees of Bristol-Myers Squibb Company at the time this research was conducted. The funder provided support in the form of salaries for authors [LJB, AEE, Y-WL, DVS, RL, KMJ, DP-M, CD, NJL, LG, TM, RP, PC, AH, RW, JC, CI, DM, YB, DK, JEM, RZ, RO] but did not have any additional role in the study design, data collection and analysis or preparation of the manuscript. While the funder had no role in the preparation of the manuscript, the manuscript was approved for external publication by Bristol-Myers Squibb Company prior to journal submission as per company policy regarding disclosure of scientific data. The specific roles of each author are articulated in the author contributions section.