Weight and Glucose Reduction Observed with a Combination of Nutritional Agents in Rodent Models Does Not Translate to Humans in a Randomized Clinical Trial with Healthy Volunteers and Subjects with Type 2 Diabetes.

BACKGROUND: Nutritional agents have modest efficacy in reducing weight and blood glucose in animal models and humans, but combinations are less well characterized. GSK2890457 (GSK457) is a combination of 4 nutritional agents, discovered by the systematic assessment of 16 potential components using the diet-induced obese mouse model, which was subsequently evaluated in a human study. NONCLINICAL RESULTS: In the diet-induced obese mouse model, GSK457 (15% w/w in chow) given with a long-acting glucagon-like peptide -1 receptor agonist, exendin-4 AlbudAb, produced weight loss of 30.8% after 28 days of treatment. In db/db mice, a model of diabetes, GSK457 (10% w/w) combined with the exendin-4 AlbudAb reduced glucose by 217 mg/dL and HbA1c by 1.2% after 14 days. CLINICAL RESULTS: GSK457 was evaluated in a 6 week randomized, placebo-controlled study that enrolled healthy subjects and subjects with type 2 diabetes to investigate changes in weight and glucose. In healthy subjects, GSK457 well tolerated when titrated up to 40 g/day, and it reduced systemic exposure of metformin by ~ 30%. In subjects with diabetes taking liraglutide 1.8 mg/day, GSK457 did not reduce weight, but it slightly decreased mean glucose by 0.356 mmol/L (95% CI: -1.409, 0.698) and HbAlc by 0.065% (95% CI: -0.495, 0.365), compared to placebo. In subjects with diabetes taking metformin, weight increased in the GSK457-treated group [adjusted mean % increase from baseline: 1.26% (95% CI: -0.24, 2.75)], and mean glucose and HbA1c were decreased slightly compared to placebo [adjusted mean glucose change from baseline: -1.22 mmol/L (95% CI: -2.45, 0.01); adjusted mean HbA1c change from baseline: -0.219% (95% CI: -0.910, 0.472)]. CONCLUSIONS: Our data demonstrate remarkable effects of GSK457 in rodent models of obesity and diabetes, but a marked lack of translation to humans. Caution should be exercised with nutritional agents when predicting human efficacy from rodent models of obesity and diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01725126.

Gut hormone pharmacology of a novel GPR119 agonist (GSK1292263), metformin, and sitagliptin in type 2 diabetes mellitus: results from two randomized studies.

UNLABELLED: GPR119 receptor agonists improve glucose metabolism and alter gut hormone profiles in animal models and healthy subjects. We therefore investigated the pharmacology of GSK1292263 (GSK263), a selective GPR119 agonist, in two randomized, placebo-controlled studies that enrolled subjects with type 2 diabetes. Study 1 had drug-naive subjects or subjects who had stopped their diabetic medications, and Study 2 had subjects taking metformin. GSK263 was administered as single (25-800 mg; n = 45) or multiple doses (100-600 mg/day for 14 days; n = 96). Placebo and sitagliptin 100 mg/day were administered as comparators. In Study 1, sitagliptin was co-administered with GSK263 or placebo on Day 14 of dosing. Oral glucose and meal challenges were used to assess the effects on plasma glucose, insulin, C-peptide, glucagon, peptide tyrosine-tyrosine (PYY), glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP). After 13 days of dosing, GSK263 significantly increased plasma total PYY levels by ∼ five-fold compared with placebo, reaching peak concentrations of ∼ 50 pM after each of the three standardized meals with the 300 mg BID dose. Co-dosing of GSK263 and metformin augmented peak concentrations to ∼ 100 pM at lunchtime. GSK263 had no effect on active or total GLP-1 or GIP, but co-dosing with metformin increased post-prandial total GLP-1, with little effect on active GLP-1. Sitagliptin increased active GLP-1, but caused a profound suppression of total PYY, GLP-1, and GIP when dosed alone or with GSK263. This suppression of peptides was reduced when sitagliptin was co-dosed with metformin. GSK263 had no significant effect on circulating glucose, insulin, C-peptide or glucagon levels. We conclude that GSK263 did not improve glucose control in type 2 diabetics, but it had profound effects on circulating PYY. The gut hormone effects of this GPR119 agonist were modulated when co-dosed with metformin and sitagliptin. Metformin may modulate negative feedback loops controlling the secretion of enteroendocrine peptides. TRIAL REGISTRATION: Clinicaltrials.gov NCT01119846 Clinicaltrials.gov NCT01128621.