Atosiban

JFDA label: Tractocile Vial

Mechanism of Action

Antagonist of Oxytocin receptor — Oxytocin receptor antagonist

Target	Action	Gene / class
Oxytocin receptor efficacy	ANTAGONIST	OXTR

Indications

Off-label

• Endometriosis
• Premature Birth

Pregnancy & Lactation

Chemistry & Properties

Formula	C43H67N11O12S2
Molecular weight	994.21 g/mol
IUPAC name	(2S)-N-[(2S)-5-amino-1-[(2-amino-2-oxoethyl)amino]-1-oxopentan-2-yl]-1-[(4R,7S,10S,13S,16R)-7-(2-amino-2-oxoethyl)-13-[(2S)-butan-2-yl]-16-[(4-ethoxyphenyl)methyl]-10-[(1R)-1-hydroxyethyl]-6,9,12,15,18-pentaoxo-1,2-dithia-5,8,11,14,17-pentazacycloicosane-4-carbonyl]pyrrolidine-2-carboxamide
CAS	90779-69-4
PubChem CID	5311010
InChIKey	VWXRQYYUEIYXCZ-OBIMUBPZSA-N
logP	-3.04 (XLogP -1.9)
Polar surface area	365.67 Ų
H-bond acceptors / donors	15 / 11
Drug-likeness (QED)	0.07
Lipinski violations	3

SMILES

CCOc1ccc(C[C@H]2NC(=O)CCSSC[C@@H](C(=O)N3CCC[C@H]3C(=O)N[C@@H](CCCN)C(=O)NCC(N)=O)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H]([C@@H](C)O)NC(=O)[C@H]([C@@H](C)CC)NC2=O)cc1

Biology & Pharmacokinetics

Pharmacokinetics predicted

Bioavailability	70.0%
Half-life	1.622 h
Volume of distribution	0.43 L/kg
Protein binding	27.9%
BBB penetrant	No

Enzyme interactions

Enzyme	Role	Detail
CYP2C19	Substrate	—

Receptor binding (top 4)

Target	Action	Affinity
VASOPRESSIN V1A (AVPR1A)	Binding	pKi 8.5
Oxytocin (OXTR)	Binding	pKi 7.1
VASOPRESSIN V1B (AVPR1B)	Binding	pKi 6.2
VASOPRESSIN V2 (AVPR2)	Binding	pKi 6.0

Transporters

BCRP (Inhibitor)BSEP (Inhibitor)BSEP (Inhibitor)MRP1 (Inhibitor)MRP2 (Inhibitor)MRP3 (Inhibitor)OATP1B1 (Inhibitor)OATP1B3 (Inhibitor)P-gp (Inhibitor)P-gp (Substrate)

Registered Products (5)

Brand	Form / strength	Pack	Agent	Citizen (JOD)
Atosiban EVER Pharma	Vial 37.5 mg/5 ml	5 ml	Sabbagh Drug Store	—
Toconorm	Vial 7.5 mg/ml	1 vial	Al Rayah drug store	—
Toconorm 6.75mg/0.9ml solution for injection	Injection 6.75 mg/0.9 ml	6.75 mg	Al Rayah drug store	—
Tractocile Vial	Vial 7.5 mg/ml	1 vial pack varies	Petra Drug Store	—
Tractocile Vial	Vial 7.5 mg/ml	5 ml pack varies	Petra Drug Store	—