2016). Recently, a clinical study demonstrated that the selective EP4 antagonist LY3127760 at daily doses of 60 mg to 600 mg was safe and tolerable in healthy subjects during oral dosing for 28 days (Jin et al. 2018). It has been reported that LY3127760 had therapeutic effects on animal models of monoiodoacetate‐induced osteoarthritis, adjuvant arthritis, and migraine headache (Blanco et al. 2016). This evidence concerns the gene PTGER4 and osteoarthritis.