Meng H. Tan

A randomized, double-blind, placebo-controlled, clinical trial of the effects of pioglitazone on glycemic control and dyslipidemia in oral antihyperglycemic medication-naive patients with type 2 diabetes mellitus.

OBJECTIVE The goal of this study was to compare the effects of 2 doses of pioglitazone hydrochloride (a thiazolidinedione insulin sensitizer) with placebo on glycated hemoglobin (HbA(1c)), insulin sensitivity, and lipid profiles in patients with type 2 diabetes mellitus who had suboptimal glycemic control and mild dyslipidemia. METHODS Patients with type 2 diabetes mellitus (HbA(1c) >/=6.5% and </=9.8%) who had not previously received insulin or oral antihyperglycemic medications (OAMs) were randomized to treatment with placebo, pioglitazone 30 mg QD, or pioglitazone 45 mg QD in double-blind fashion for 16 weeks at 41 centers in Canada and Spain. RESULTS A total of 297 patients were randomized (99 in each group). Overall, 286 (96.3%) were white. Mean (SD) age was 58.4 (10.9) years (range, 24-85 years), mean (SD) body mass index was 31.4 (4.8) kg/m(2), mean (SD) duration of type 2 diabetes mellitus was 20.0 (37.4) months, and 30.6% of patients were receiving medication for dyslipidemia. Treatment with pioglitazone 30 or 45 mg QD for 16 weeks reduced mean HbA(1c) by 0.8% and 0.9% from baseline, respectively (both P < 0.001 vs baseline and placebo). A reduction in HbA(1c) of 0.2% was observed in the placebo group (P = 0.025). In patients with medium (>/=7% to <8%) or high (>/=8% to </=9.8%) baseline HbA(1c), both doses of pioglitazone significantly reduced HbA(1c) (both P < 0.001 vs placebo). Pioglitazone 30 and 45 mg significantly reduced fasting serum insulin versus placebo (P = 0.008 and P = 0.006, respectively) and increased insulin sensitivity by Homeostasis Model Assessment versus placebo (P = 0.039 and P = 0.001, respectively). Relative to placebo, pioglitazone 30 and 45 mg significantly increased high-density lipoprotein cholesterol (HDL-C [P = 0.028 and P < 0.001, respectively]) and lowered the atherogenic index of plasma (P = 0.018 and P < 0.001, respectively). Pioglitazone 45 mg also significantly reduced serum triglycerides, apolipoprotein B, and total cholesterol:HDL-C ratio versus placebo (P = 0.007, P = 0.015, and P = 0.005, respectively). Pioglitazone 30 and 45 mg were associated with a significant reduction in serum alanine aminotransferase relative to placebo (P = 0.036 and P = 0.005, respectively). Pioglitazone appeared to be safe and was well tolerated. CONCLUSIONS In the present study, pioglitazone 30 and 45 mg produced significant improvements in HbA(1c), insulin sensitivity, and lipid profile in OAM-naive patients with type 2 diabetes mellitus with suboptimal glycemic control and mild dyslipidemia.

Pioglitazone versus Rosiglitazone: Effects on Lipids, Lipoproteins, and Apolipoproteins in Head-to-Head Randomized Clinical Studies.

Peroxisome proliferator-activated receptors (PPARs) play an important role in regulating both glucose and lipid metabolism. Agonists for both PPARγ and PPARγ have been used to treat dyslipidemia and hyperglycemia, respectively. In addition to affecting glucose metabolism, PPARγ agonists also regulate lipid metabolism. In this review, we will focus on the randomized clinical trials that directly compared the lipid effects of the thiazolidinedione class of PPARγ agonists, pioglitazone and rosiglitazone, head-to-head either as monotherapy or in combination with other lipid-altering or glucose-lowering agents

Pioglitazone as monotherapy or in combination with sulfonylurea or metformin enhances insulin sensitivity (HOMA-S or QUICKI) in patients with type 2 diabetes

Background: Miyazaki etal, demonstrated using the hyperinsulinemic, euglycemic clamp that pioglitazone (PIO) enhanced insulin sensitivity in patients (n = 23) with type 2 diabetes (T2D). Although considered the reference method for measuring insulin sensitivity, the clamp is seldom used in large clinical trials because of its complexity. The Homeostasis Model Assessment-Insulin Sensitivity (HOMA-S) and Quantitative Insulin Sensitivity Check Index (QUICKI) are two alternative insulin sensitivity surrogates that correlate with the clamp method and are suitable for use with large study populations. Study aim: To evaluate the effect of PIO monotherapy and in combination therapy with sulfonylurea (SU) or metformin (MET) on insulin sensitivity as assessed by HOMA-S and QUICKI in a large group of patients (∼1000). Research design and methods: Patient data from three randomized, double blind, multicenter, parallel group, placebo-controlled registration trials (Studies-001 PIO monotherapy and 010 and 027 combination therapy with SU or MET, respectively) were analyzed for this study. We evaluated insulin sensitivity for all three studies using HOMA-S and QUICKI. Results: PIO 15, 30 and 45 mg enhanced HOMA-S compared with baseline (56.9-63.6%, p = 0.0298); (53.7-64.7%, p = 0.0008); (59.0-75.9%, p < 0.0001), respectively. Only the 45 mg dose showed a difference from placebo (p = 0.0025). Similarly, PIO enhanced QUICKI versus baseline (0.290-0.296, p = 0.0026); (0.287-0.299, p = 0.0001); (0.290-0.306, p = 0.0001), respectively. Both the 30 and 45mg doses were different from placebo for QUICKI (p = 0.0005, p < 0.0001). PIO 15 and 30mg plus SU enhanced HOMA-S compared with baseline (58.4–.7%, p = 0.0007; 53.2–68.4%, p < 0.0001) and placebo plus SU (p = 0.0129, p < 0.0001, respectively). Likewise, PIO 15 and 30 mg plus SU enhanced QUICKI versus baseline (0.289-0.300, p = 0.0001; 0.287-0.305, p = 0.0001, respectively). Both doses had different effects from placebo plus SU (p = 0.0001) for QUICKI. PIO 30mg combined with MET enhanced HOMA-S versus baseline (66.2–82.2%, p < 0.0001) and placebo plus MET (p = 0.0002).