The pharmacological effect of BGC20-1531, a novel prostanoid EP ₄ receptor antagonist, in the Prostaglandin E ₂ human model of headache

Using a human Prostaglandin E ₂ (PGE ₂) model of headache, we examined whether a novel potent and selective EP ₄ receptor antagonist, BGC20-1531, may prevent headache and dilatation of the middle cerebral (MCA) and superficial temporal artery (STA). In a three-way cross-over trial, eight healthy volunteers were randomly allocated to receive 200 and 400 mg BGC20-1531 and placebo, followed by a 25-min infusion of PGE ₂. We recorded headache intensity on a verbal rating scale, MCA blood flow velocity and STA diameter. There was no difference in headache response or prevention of the dilation of the MCA or the STA (P > 0.05) with either dose of BGC20-1531 relative to placebo, although putative therapeutic exposures were not reached in all volunteers. In conclusion, these data suggest that the other EP receptors may be involved in PGE ₂ induced headache and dilatation in normal subjects.