Grapiprant (415903-37-6) Description:

Grapiprant, also known as CJ-023,423, RQ-00000007 and AAT-007, is a novel, potent and selective prostaglandin EP4 receptor antagonist with antihyperalgesic properties. It is currently under development for use in humans and dogs for the control of pain and inflammation associated with osteoarthritis.

In vitro, 415903-37-6 inhibits [(3)H]PGE(2) binding to both human and rat EP(4) receptors with K(i) of 13 +/- 4 and 20 +/- 1 nM, respectively. CJ-023,423 is highly selective for the human EP(4) receptor over other human prostanoid receptor subtypes. It also inhibits PGE(2)-evoked elevation in intracellular cAMP at the human and rat EP(4) receptors with pA(2) of 8.3 +/- 0.03 and 8.2 +/- 0.2 nM, respectively. In vivo, oral administration of CJ-023,423 significantly reduces thermal hyperalgesia induced by intraplantar injection of PGE(2) (ED(50) = 12.8 mg/kg).