PTGDR2 and type 2 diabetes mellitus: Treatment with the GPR44/DP2 antagonist AZD1981 at steady state exposure (AZD1981 at 100 mg BID for three days) did not exert any clinically significant insulinotropic effect in T2DM patients on metformin (Fig 6 and Table 2) for any of the co-primary variables in the study.