kappa opioid ( Ki = 0.807 nM )

Aticaprant (CERC-501) binds to the human kappa opioid receptor with great affinity; it is 30 times more soluble than the human mu opioid receptor and 190 times more soluble than the human delta opioid receptor. For a number of non-opioid cell surface G-protein-coupled receptor targets, such as the central benzodiazepine binding site, ion channel/transporter binding targets, muscarinic, cholinergic, and adrenergic receptors, aticaprant (CERC-501) exhibits no discernible affinity[1].

Aticaprant (CERC-501) exhibits a good oral bioavailability (F=25%) and a rapid absorption (t_max=1-2 h). Without showing any signs of mu or delta receptor occupancy, oral administration of Aticaprant (CERC-501) selectively and potently occupies central kappa opioid receptors (ED50=0.33 mg/kg). At doses more than thirty times higher than LY2456302, kappa-agonist-mediated analgesia and prepulse inhibition disruption are potently blocked without compromising mu-agonist-mediated effects. In the mouse forced swim test, aticaprant (CERC-501) mimics the effects of antidepressants and amplifies the benefits of citalopram and imipramine. In rats that prefer alcohol, aticaprant (CERC-501) lowers ethanol self-administration[1]. According to pre-treatment mice that had been nicotine-withdrawn, aticaprant (CERC-501) reduces the symptoms of the nicotine withdrawal syndrome, as demonstrated by decreased expression of anxiety-related behavior, somatic signs, and CPA as well as increased hotplate latency[2].

In vitro receptor binding and functional activity[1]
In vitro opioid receptor binding and [35S]-GTPγS binding experiments were conducted as previously described (Mitch et al., 2011). Briefly, radioligand displacement studies with [3H]diprenorphine were carried out using membranes prepared from CHO cells expressing cloned human κ and μ opioid receptors or HEK293 cells expressing the cloned δ opioid receptor. Concentrations causing 50% inhibition (IC50) of [3H]-diprenorphine binding were determined from 11-point concentration response curves in assay buffer containing sodium and guanosine diphosphate (GDP). Naltrexone was included as a control at 10 μM to define nonspecific binding and was also tested as a comparator molecule in concentration response curves.

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In vivo receptor occupancy[1]
The ability of orally administered LY2456302 to occupy brain mu, delta, and kappa opioid receptors in vivo was assessed in male Sprague-Dawley (SD) rats (Harlan, Indianapolis, IN), weighing 250–300 g, n = 4/dose. Kappa opioid occupancy was measured in male NIH-Swiss mice, weighing 25–30 g, n = 4/dose. Receptor occupancy (RO) was determined 90 min after a PO dose of LY2456302 by measuring displacement of unlabeled tracers by LC–MS/MS (Need et al., 2007). Tracers for mu, kappa, and delta receptors, were naltrexone (10 μg/kg), naltriben (10 μg/kg), and GR103545 (1.5 μg/kg), respectively, administered as a single IV injection (Need et al., 2007). In a separate study, RO was determined by LC–MS/MS in male SD rats (Harlan, Indianapolis, IN, 250–300 g, n = 4/dose) at 1, 4, 8, and 48 h after a 10 mg/kg PO dose of LY2456302. Total binding was represented by levels of tracers in the striatum for delta and kappa receptors, and thalamus for the mu receptor. The cerebellum, which contains significantly lower densities of mu, kappa, or delta receptors, was used for measuring nonspecific binding (Mansour et al., 1994). Receptor occupancies were calculated by using the ratio method described by Wadenberg et al. (2000), but substituting the tracer concentrations determined by LC/MS/MS for the radiolabeled tracer levels determined with scintillation spectrometry. The following equation was employed: Each ‘Ratio’ refers to the ratio of tracer in a brain area rich in target receptor relative to the tracer detected in the cerebellum. ‘Ratiot’ refers to animals treated with test drug, while ‘Ratioc’ refers to the average ratio in vehicle-treated animals. ED50 curves, where reported, were calculated from experimental values using 4-parameter non-linear regression curve fit. The lower and upper bounds were not fixed in these calculations.

Rat and mouse plasma exposure and unbound fraction in plasma and brain<[1]
Three male cannulated rats were administered a single 1 mg/kg intravenous (IV) and 10 mg/kg oral (PO) dose of LY2456302 to determine the pharmacokinetic parameters. Plasma samples were collected at 0.08 (IV only), 0.25, 0.5, 1, 2, 4, 8, 12 and 24 h post-dose and analyzed by liquid chromatography coupled to tandem mass spectral detection (LC–MS/MS) to determine the concentrations of LY2456302. Male mice (n = 3 per time point) were administered a single 10 mg/kg PO dose of LY2456302 to determine the pharmacokinetic parameters. Plasma samples were collected at 0.5, 1, 2, 4, 8, and 24 h post-dose and analyzed by LC–MS/MS to determine the concentrations of LY2456302. The plasma and brain binding of LY2456302 was determined by equilibrium dialysis at 1 μM.

Rats: The pharmacokinetic parameters of Aticaprant (CERC-501) are ascertained by giving a single intravenous (IV) dose of 1 mg/kg and an oral (PO) dose of 10 mg/kg to three male cannulated rats. Aticaprant (CERC-501) concentrations are ascertained by liquid chromatography coupled to tandem mass spectral detection analysis of plasma samples obtained at 0.08 (IV only), 0.25, 0.5, 1, 2, 4, 8, 12 and 24 hours post-dose[1].

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Mice: To ascertain the pharmacokinetic parameters, male mice receive a single oral dose of Aticaprant (10 mg/kg CERC-501). The amounts of Aticaprant are found by LCeMS/MS analysis of plasma samples taken at 0.5, 1, 2, 4, 8, and 24 hours after dosage (CERC-501). By using equilibrium dialysis at a concentration of 1 μM, the binding of Aticaprant (CERC-501) to the brain and plasma is found[1].

[1]. LY2456302 is a novel, potent, orally-bioavailable small molecule kappa-selective antagonist with activity in animal models predictive of efficacy in mood and addictive disorders. Neuropharmacology. 2014 Feb;77:131-44.

[2]. Effects of orally-bioavailable short-acting kappa opioid receptor-selective antagonist LY2456302on nicotine withdrawal in mice. Neuropharmacology. 2015 Oct;97:270-4.

Aticaprant has been used in trials studying the health services research and basic science of Anxiety Disorders and Alcohol Dependence.

C26H27FN2O2

418.50318

418.206

C, 74.62; H, 6.50; F, 4.54; N, 6.69; O, 7.65

1174130-61-0

44129648

White to off-white solid powder

6.492

1

4

6

31

584

1

O=C(N)C1=CC=C(OC2=CC=C(CN3[C@H](C4=CC(C)=CC(C)=C4)CCC3)C=C2)C(F)=C1

ZHPMYDSXGRRERG-DEOSSOPVSA-N

InChI=1S/C26H27FN2O2/c1-17-12-18(2)14-21(13-17)24-4-3-11-29(24)16-19-5-8-22(9-6-19)31-25-10-7-20(26(28)30)15-23(25)27/h5-10,12-15,24H,3-4,11,16H2,1-2H3,(H2,28,30)/t24-/m0/s1

4-[4-[[(2S)-2-(3,5-dimethylphenyl)pyrrolidin-1-yl]methyl]phenoxy]-3-fluorobenzamide

JNJ67953964; CERC-501; LY-2456302; (S)-4-(4-((2-(3,5-diMethylphenyl)pyrrolidin-1-yl)Methyl)phenoxy)-3-fluorobenzaMide; LY2456302; CERC-501; JSPA0658; JSPA-0658; JNJ 67953964; CERC501; LY2456302; CERC 501; LY 2456302; JNJ-67953964

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: ≥ 100 mg/mL (~239.0 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.97 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.5 mg/mL (5.97 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (5.97 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)