Epelsiban  (Synonyms: GSK 557296)

Epelsiban (GSK 557296) is a potent, selective and orally bioavailable oxytocin receptor antagonist, with a pK_i of 9.9 for human oxytocin receptor.

pKi: 9.9 (human oxytocin receptor)^[1]
IC50: 192 nM (human oxytocin receptor)^[1]

Epelsiban is a potent oxytocin receptor, with a pK_i of 9.9 for human oxytocin receptor, >31000-fold selectivity over all three human vasopressin receptors hV1aR (pK_i, <5.2), hV2R (pK_i, <5.1), and hV1bR (pK_i, 5.4), and shows no significant P450 inhibition^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Epelsiban shows an IC₅₀ of 192 nM for oxytocin receptor in rats. Epelsiban has low levels of intrinsic clearance against the microsomes of rat, dog, and cynomolgus monkey, good bioavailability (55%), but is negative in the genotoxicity screens with a satisfactory oral safety profile in female rats^[1].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

518.65

C₃₀H₃₈N₄O₄

872599-83-2

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Borthwick AD, et al. Pyridyl-2,5-diketopiperazines as potent, selective, and orally bioavailable oxytocin antagonists: synthesis, pharmacokinetics, and in vivo potency. J Med Chem. 2012 Jan 26;55(2):783-96.  [Content Brief]