Ipragliflozin as an Initial Therapy in Drug Naïve Subjects with Type 2 Diabetes

Efficacy and safety of ipragliflozin as an add-on therapy to sitagliptin and metformin in Korean patients with inadequately controlled type 2 diabetes mellitus: A randomized controlled trial

AIM

To evaluate the efficacy and safety of ipragliflozin vs placebo as add-on therapy to metformin and sitagliptin in Korean patients with type 2 diabetes mellitus (T2DM).

METHODS

This double-blind, placebo-controlled, multi-centre, phase III study was conducted in Korea in 2015 to 2017. Patients were randomized to receive either ipragliflozin 50 mg/day or placebo once daily for 24 weeks in addition to metformin and sitagliptin. The primary endpoint was the change in glycated haemoglobin (HbA1c) from baseline to end of treatment (EOT).

RESULTS

In total, 143 patients were randomized and 139 were included in efficacy analyses (ipragliflozin: 73, placebo: 66). Baseline mean (SD) HbA1c levels were 7.90 (0.69)% for ipragliflozin add-on and 7.92 (0.79)% for placebo. The corresponding mean (SD) changes from baseline to EOT were -0.79 (0.59)% and 0.03 (0.84)%, respectively, in favour of ipragliflozin (adjusted mean difference -0.83% [95% CI -1.07 to -0.59]; P < .0001). More ipragliflozin-treated patients than placebo-treated patients achieved HbA1c target levels of <7.0% (44.4% vs 12.1%) and < 6.5% (12.5% vs 1.5%) at EOT (P < .05 for both). Fasting plasma glucose, fasting serum insulin, body weight and homeostatic model assessment of insulin resistance decreased significantly at EOT, in favour of ipragliflozin (adjusted mean difference -1.64 mmol/L, -1.50 μU/mL, -1.72 kg, and -0.99, respectively; P < .05 for all). Adverse event rates were similar between groups (ipragliflozin: 51.4%; placebo: 50.0%). No previously unreported safety concerns were noted.

CONCLUSIONS

Ipragliflozin as add-on to metformin and sitagliptin significantly improved glycaemic variables and demonstrated a good safety profile in Korean patients with inadequately controlled T2DM.

Canagliflozin as an Initial Therapy in Drug-Naïve Subjects with Type 2 Diabetes Mellitus: A Potential Involvement of Atherogenic Lipids in its Glycemic Efficacy

Background and Objectives

The aim of this study is to investigate canagliflozin as an initial therapy in type 2 diabetes mellitus and to explore the effects on metabolic parameters in relation to effects on glycemic control.

Subjects and Methods

Treatment-naïve subjects with type 2 diabetes mellitus received canagliflozin 50–100 mg/day monotherapy. At 3 months, levels of glycemic and non-glycemic parameters were compared with those at baseline (n = 39). As a comparator, our previous data of baseline glycosylated hemoglobin (HbA_1c)-matched treatment-naïve subjects with ipragliflozin 25–50 mg monotherapy (n = 27) were employed.

Results

Significant reductions in HbA_1c (from 9.96 to 8.33%), fasting blood glucose (−23.9%), homeostasis model assessment-R (HOMA-R, −33.5%), body mass index (−1.8%), and uric acid (UA, −5.2%) levels and significant increases in homeostasis model assessment-B (HOMA-B, 30.1%) levels were observed. Approximately one third of the subjects experienced certain adverse events. Similar results were obtained with ipragliflozin. Baseline levels of HbA_1c, triglycerides, non-high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) were chosen as significant contributing factors for the changes in HbA_1c levels with canagliflzoin, while only baseline HbA_1c levels were selected as such a factor with ipragliflozin. Significant positive correlations between the changes in HbA_1c and changes in non-HDL-C (R = 0.3954) or between changes in HbA_1c and changes in LDL-C (R = 0.4317) were observed with canagliflozin. With ipragliflozin, no such correlations were noted. No correlations between the changes in HbA_1c and changes in body mass index were seen with both drugs.

Conclusions

These results suggest that (1) canagliflozin appears to offer clinically beneficial outcomes as an initial therapy in subjects with type 2 diabetes mellitus, although with certain adverse events. (2) Atherogenic cholesterols including non-HDL-C and LDL-C could be involved in the glycemic efficacy of canagliflozin. This was not the case with ipragliflozin. (3) Unexpectedly, weight reductions with canagliflozin are not associated with its glycemic efficacy.

Distinct Glucose-Lowering Mechanisms of Ipragliflozin Depending on Body Weight Changes

BACKGROUND

Sodium-glucose co-transporter 2 inhibitors have been shown to reduce body weight. However, little is known about whether a reduction in body weight affects glycemic and non-glycemic parameters.

OBJECTIVES

The aim of this study was to investigate the link between the changes in body weight and those in metabolic parameters in drug-naïve subjects with type 2 diabetes mellitus (T2DM) receiving ipragliflozin monotherapy.

METHODS

Subjects received ipragliflozin monotherapy 25-50 mg/day for 3 months (n = 33). They were then divided into two groups: group L ('lost'; n = 17) comprised patients who lost weight (change [Δ] in body mass index [BMI] ≤ -0.75, p < 0.00001), and group N ('neutral'; n = 16) comprised patients who did not lose weight (ΔBMI > -0.75, not significant [NS]).

RESULTS

In these two groups, similar reductions were observed in glycated hemoglobin (HbA_1c) levels (group L: 9.76-8.02%, p < 0.00001; group N: 10.07-8.36%, p < 0.0005). Homeostasis model assessment (HOMA)-B levels increased in both groups, with inter-group differences (p < 0.05; +38.91 vs. +96.83% in group L and N, respectively). However, some parameters showed distinct regulatory patterns. For instance, in group L, reductions were observed in HOMA-R (-20.18%, p < 0.04) and uric acid (UA; -8.91%, p < 0.02) levels. Correlations were seen between the change in HOMA-R and those in fasting blood glucose (FBG) levels (R = 0.557, p < 0.02). Non-significant increases in free fatty acid (FFA) levels and decreases in non-high-density lipoprotein cholesterol (non-HDL-C) or low-density lipoprotein cholesterol (LDL-C) levels were also noted. In group N, reductions in FFA levels (-17.07%, p < 0.05) were observed, and negative correlations were seen between ΔHOMA-B and ΔFBG (R = -0.4781, p < 0.05) and between Δ FFA and Δ HOMA-B levels (R = -0.4305, p < 0.05). Non-significant increases in non-HDL-C and LDL-C levels were also noted. Inter-group differences existed between group L and group N in the changes in non-HDL-C and LDL-C levels (both p < 0.05).

CONCLUSIONS

These results indicate that ipragliflozin may possess distinct dual glucose-lowering mechanisms depending on body weight changes. Degrees of insulin resistance decrease in subjects who lose weight. Conversely, ipragliflozin reduces lipotoxicity (FFA levels), thereby activating beta-cell function, in subjects who do not lose weight. Similar glycemic efficacies were observed in both cases. In patients who lost weight, ipragliflozin was associated with improvements in the levels of metabolic parameters related to cardiovascular risk factors, including UA and atherogenic lipid levels (non-HDL-C and LDL-C) compared with those who did not lose weight.

New Pathogenic Concepts and Therapeutic Approaches to Oxidative Stress in Chronic Kidney Disease

In chronic kidney disease inflammatory processes and stimulation of immune cells result in overproduction of free radicals. In combination with a reduced antioxidant capacity this causes oxidative stress. This review focuses on current pathogenic concepts of oxidative stress for the decline of kidney function and development of cardiovascular complications. We discuss the impact of mitochondrial alterations and dysfunction, a pathogenic role for hyperuricemia, and disturbances of vitamin D metabolism and signal transduction. Recent antioxidant therapy options including the use of vitamin D and pharmacologic therapies for hyperuricemia are discussed. Finally, we review some new therapy options in diabetic nephropathy including antidiabetic agents (noninsulin dependent), plant antioxidants, and food components as alternative antioxidant therapies.