(R)-Vorbipiprant
(R)-Vorbipiprant R)-CR6086) is an orally active antagonist for prostaglandin E2 receptor 4 (EP4) with Ki of 16.6 nM for human EP4. (R)-Vorbipiprant inhibits PGE2 (HY-101952)-induced cAMP production with an IC50 of 22 nM. (R)-Vorbipiprant exhibits immunomodulatory and anti-angiogenic activities, and ameliorates the collagen-induced arthritis in mice.