Identification
Name Varenicline
Accession Number DB01273
Type small molecule
Description Varenicline is a prescription medication used to treat smoking addiction. This medication is the first approved nicotinic receptor partial agonist. Specifically, varenicline is a partial agonist of the alpha4/beta2 subtype of the nicotinic acetylcholine receptor. In addition it acts on alpha3/beta4 and weakly on alpha3beta2 and alpha6-containing receptors. A full agonism was displayed on alpha7-receptors.
Structure
Categories (*)
Molecular Weight 211.2624
Groups approved
Monoisotopic Weight 211.110947431
Pharmacology
Indication For use as an aid in smoking cessation.
Mechanism of action Varenicline is an alpha-4 beta-2 neuronal nicotinic acetylcholine receptor partial agonist. The drug shows high selectiviyty for this receptor subclass, relative to other nicotinic receptors (>500-fold alpha-3 beta-4, >3500-fold alpha-7, >20,000-fold alpha-1 beta gamma delta) or non-nicotinic receptors and transporters (>2000-fold). The drug competitively inhibits the ability of nicotine to bind to and activate the alpha-4 beta-2 receptor. The drug exerts mild agonistic activity at this site, though at a level much lower than nicotine; it is presumed that this activation eases withdrawal symptoms.
Absorption Not Available
Protein binding Less than 20%.
Biotransformation Metabolism is limited (<10%). Most of the active compound is excreted renally (81%). A small proportion is glucuronidated, oxidated, N-formylated or conjugated to a hexose.
Route of elimination Varenicline undergoes minimal metabolism, with 92% excreted unchanged in the urine. Renal elimination of varenicline is primarily through glomerular filtration along with active tubular secretion possibly via the organic cation transporter, OCT2.
Toxicity Not Available
Affected organisms
  • Humans and other mammals
Interactions
Drug Interactions Not Available
Food Interactions Not Available
Neuronal acetylcholine receptor subunit alpha-4
Name Neuronal acetylcholine receptor subunit alpha-4
Gene Name CHRNA4
Pharmacological action yes
Actions partial agonist
References
  • Nakamura M, Oshima A, Fujimoto Y, Maruyama N, Ishibashi T, Reeves KR: Efficacy and tolerability of varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, in a 12-week, randomized, placebo-controlled, dose-response study with 40-week follow-up for smoking cessation in Japanese smokers. Clin Ther. 2007 Jun;29(6):1040-56. - Pubmed
  • McColl S, Burstein A, Reeves K, Billing Jr C, Stolar M, Sellers E: Human Abuse Liability of the Smoking Cessation Drug Varenicline in Smokers and Nonsmokers. Clin Pharmacol Ther. 2008 Feb 20;. - Pubmed
  • Rollema H, Coe JW, Chambers LK, Hurst RS, Stahl SM, Williams KE: Rationale, pharmacology and clinical efficacy of partial agonists of alpha4beta2 nACh receptors for smoking cessation. Trends Pharmacol Sci. 2007 Jul;28(7):316-25. Epub 2007 Jun 18. - Pubmed
  • Steensland P, Simms JA, Holgate J, Richards JK, Bartlett SE: Varenicline, an alpha4beta2 nicotinic acetylcholine receptor partial agonist, selectively decreases ethanol consumption and seeking. Proc Natl Acad Sci U S A. 2007 Jul 24;104(30):12518-23. Epub 2007 Jul 11. - Pubmed
  • Chen X, Ji ZL, Chen YZ: TTD: Therapeutic Target Database. Nucleic Acids Res. 2002 Jan 1;30(1):412-5. - Pubmed
DTHybrid score 0.3986
Neuronal acetylcholine receptor subunit alpha-7
Name Neuronal acetylcholine receptor subunit alpha-7
Gene Name CHRNA7
Pharmacological action unknown
Actions agonist
References
  • Mihalak KB, Carroll FI, Luetje CW: Varenicline is a partial agonist at alpha4beta2 and a full agonist at alpha7 neuronal nicotinic receptors. Mol Pharmacol. 2006 Sep;70(3):801-5. Epub 2006 Jun 9. - Pubmed
DTHybrid score 0.3934
Neuronal acetylcholine receptor subunit alpha-3
Name Neuronal acetylcholine receptor subunit alpha-3
Gene Name CHRNA3
Pharmacological action unknown
Actions partial agonist
References
  • Mihalak KB, Carroll FI, Luetje CW: Varenicline is a partial agonist at alpha4beta2 and a full agonist at alpha7 neuronal nicotinic receptors. Mol Pharmacol. 2006 Sep;70(3):801-5. Epub 2006 Jun 9. - Pubmed
DTHybrid score 0.4736
Neuronal acetylcholine receptor subunit alpha-6
Name Neuronal acetylcholine receptor subunit alpha-6
Gene Name CHRNA6
Pharmacological action unknown
Actions partial agonist
References
  • Mihalak KB, Carroll FI, Luetje CW: Varenicline is a partial agonist at alpha4beta2 and a full agonist at alpha7 neuronal nicotinic receptors. Mol Pharmacol. 2006 Sep;70(3):801-5. Epub 2006 Jun 9. - Pubmed
DTHybrid score 0.3189
Id Partner name Gene Name Score
918 Glutamate receptor, ionotropic kainate 2 GRIK2 0.1854
6078 Neuronal acetylcholine receptor subunit beta-4 CHRNB4 0.163
841 Gamma-aminobutyric-acid receptor subunit alpha-6 GABRA6 0.1615
530 Gamma-aminobutyric-acid receptor subunit alpha-4 GABRA4 0.1598
921 Glutamate receptor 2 GRIA2 0.1516
523 Gamma-aminobutyric-acid receptor subunit alpha-5 GABRA5 0.1455
580 Gamma-aminobutyric-acid receptor subunit alpha-3 GABRA3 0.1454
423 Gamma-aminobutyric-acid receptor subunit alpha-2 GABRA2 0.1448
872 Gamma-aminobutyric-acid receptor subunit alpha-1 GABRA1 0.1334
458 Neuronal acetylcholine receptor subunit alpha-10 CHRNA10 0.1162
1075 Alkaline phosphatase, placental-like ALPPL2 0.1024
6082 Neuronal acetylcholine receptor subunit beta-3 CHRNB3 0.0883
6080 Neuronal acetylcholine receptor subunit alpha-5 CHRNA5 0.0881
948 Neuronal acetylcholine receptor subunit beta-2 CHRNB2 0.088
4097 Neuronal acetylcholine receptor subunit alpha-9 CHRNA9 0.0756
4512 Cytochrome P450 3A4 CYP3A4 0.0582
813 Neuronal acetylcholine receptor subunit alpha-2 CHRNA2 0.0509
4119 Cytochrome P450 2D6 CYP2D6 0.0349
6030 Cytochrome P450 2B6 CYP2B6 0.0325
6016 Cytochrome P450 2C19 CYP2C19 0.0325
4200 Cytochrome P450 1A2 CYP1A2 0.0323
6013 Cytochrome P450 2E1 CYP2E1 0.0319
5718 Cytochrome P450 2A6 CYP2A6 0.0315
4757 Cytochrome P450 2C9 CYP2C9 0.0312
4924 Cytochrome P450 2C8 CYP2C8 0.0296
474 Acetylcholinesterase ACHE 0.0267
3923 Cholinesterase BCHE 0.0257
6014 Cytochrome P450 2A13 CYP2A13 0.0239
847 Mu-type opioid receptor OPRM1 0.0164
3811 Cytochrome P450 19A1 CYP19A1 0.0159
6147 Solute carrier family 22 member 3 SLC22A3 0.0156
3941 Amine oxidase [flavin-containing] A MAOA 0.0155
833 Organic cation/carnitine transporter 1 SLC22A4 0.0154
3939 Amine oxidase [flavin-containing] B MAOB 0.0152
6107 Cytochrome P450 3A7 CYP3A7 0.0151
6024 Cytochrome P450 1A1 CYP1A1 0.0151
4118 Cytochrome P450 3A5 CYP3A5 0.0142
118 Organic cation/carnitine transporter 2 SLC22A5 0.0136
6144 Solute carrier family 22 member 2 SLC22A2 0.0135
6145 Solute carrier family 22 member 1 SLC22A1 0.013
3937 Fatty-acid amide hydrolase FAAH 0.0108
713 Sodium-dependent dopamine transporter SLC6A3 0.01
540 Sodium-dependent noradrenaline transporter SLC6A2 0.0092
1181 Alpha-1-acid glycoprotein 1 ORM1 0.0092
20 Prostaglandin G/H synthase 1 PTGS1 0.0049
468 Cytochrome P450 4A11 CYP4A11 0.0041
6152 Solute carrier organic anion transporter family member 2A1 SLCO2A1 0.0039
6106 Cytochrome P450 2C18 CYP2C18 0.0034
1709 Canalicular multispecific organic anion transporter 2 ABCC3 0.0033
1898 Cytochrome P450 1B1 CYP1B1 0.0033
776 Bile salt export pump ABCB11 0.0031
862 Multidrug resistance-associated protein 1 ABCC1 0.0029
1735 Canalicular multispecific organic anion transporter 1 ABCC2 0.0027
1588 Multidrug resistance protein 1 ABCB1 0.0021