Pharmacometric Approaches to Guide Dose Selection of the Novel GPR40 Agonist TAK-875 in Subjects With Type 2 Diabetes Mellitus

The G-protein-coupled receptor 40 agonist (GPR40) TAK-875 is being developed as an adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes mellitus. Pharmacometric approaches such as model-based exposure-response and meta-analyses were applied to (i) characterize exposure/dose–efficacy responses of TAK-875, (ii) characterize the time course of glycosylated hemoglobin A1c (HbA1c) response with TAK-875 6.25 to 200 mg q.d. doses for 12 weeks, (iii) project and compare HbA1c response with dipeptidyl peptidase 4 (DPP-4) inhibitors and TAK-875 up to 24 weeks, and (iv) provide a quantitative rationale for dose selection in phase 3. On the basis of phase 2 data, relationships between TAK-875 concentrations and HbA1c were well characterized by exposure–response models. EC(50) and E(max) of TAK-875 were estimated to be 3.16 µg/ml and 0.366, respectively. Model-based simulations over 24 weeks indicated that the 25- and 50-mg q.d. doses of TAK-875 achieve efficacy as comparable with or better than that of commonly used antidiabetic agents.