Effects of linagliptin monotherapy compared with voglibose on postprandial blood glucose responses in Japanese patients with type 2 diabetes: Linagliptin Study of Effects on Postprandial blood glucose (L-STEP)

Efficacy and Safety of Metformin Versus the Other Oral Antidiabetic Drugs in Japanese Type 2 Diabetes Patients: A Network Meta-analysis

Introduction

Although metformin is recommended as a first-line treatment for patients with type 2 diabetes (T2D) in Western countries, no specific treatment is recommended in Japan, and various agents are used. Metformin has long been used at low doses in Japan, and information regarding its effect at the maximum maintenance dose is lacking. Here, we compared the efficacy and safety of metformin at 1500 mg/day with those of the other oral anti-diabetic drugs (OADs) approved in Japan.

Methods

Randomized controlled trials comparing a change in hemoglobin A1c (HbA1c) from baseline at 12 weeks or later (ΔHbA1c) among OADs (including placebo) as a first-line treatment in adult patients with T2D were selected by systematic review with comprehensive searching of CENTRAL, MEDLINE, Ichushi Web, and EMBASE and manual searching of clinical trial registries. The ΔHbA1c and incidence of hypoglycemia were compared among OAD treatments using Bayesian network meta-analysis (NMA). The relative risk (RR) of the incidence of hypoglycemia was determined relative to that of placebo.

Results

Forty-six randomized controlled trials were identified in the systematic review, and 37 studies, comprising 38 different types of treatments, including placebos, were selected for the NMA of ΔHbA1c. Compared with metformin 1500 mg/day, 20 OAD treatments were significantly less effective in reducing HbA1c from baseline (differences from metformin 1500 mg/day: 0.40–0.96%). Two treatments (glimepiride 2 mg/day and pioglitazone 45 mg/day) showed greater mean reductions in HbA1c from baseline than metformin 1500 mg/day (− 0.38% and − 0.03%), although these differences were not significant. Regarding the incidence of hypoglycemia, only pioglitazone 30 mg/day among 31 treatments showed a lower RR (< − 0.01), whereas 23 treatments showed a significantly higher RR (1.02–66.71) than metformin 1500 mg/day.

Conclusion

The NMA suggested a preferable efficacy and safety profile of metformin 1500 mg/day compared with the other OADs approved in Japan.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01979-1.

Comparison of Glycemic Excursion Using Flash Continuous Glucose Monitoring in Patients with Type 2 Diabetes Mellitus Before and After Treatment with Voglibose

Purpose: To determine the effect of Voglibose add-on therapy on daily glycemic excursions (using FreeStyle^® Libre Pro™, a Flash glucose monitoring system) in Indian patients with type 2 diabetes mellitus (T2DM) receiving a stable dose of metformin (Met) or metformin+sulfonylurea (Met+SU). Patients and Methods: T2DM patients with glycosylated hemoglobin (HbA1c) ≥7.0% and at least two postprandial excursions ≥140 mg/dL (within 2 h of meal) during the screening phase (visit 1/day -14 ± 2) were enrolled in this prospective, multicenter interventional study. The patients were randomized at visit 2 (day 0 ± 2) to receive Voglibose 0.2 or 0.3 mg tablets (BID/TID) as add-on therapy to Met and Met+SU. All the patients were followed at day 14 ± 2 (visit 3), month 3 ± 14 days (visit 4), 14 weeks (i.e., visit 4 + 14 days) ±2 days (visit 5), and month 6 ± 14 days (visit 6). Continuous glucose monitoring was performed to study glycemic excursions at visits 2, 3, and 5. The study outcomes were: change in average number of glycemic excursions per day, percent time spent in glucose fluctuations, mean Postprandial glucose (PPG), Fasting plasma glucose (FPG), day and night time mean glucose levels from baseline to day 14 and week 14; change in mean amplitude of glycemic excursion (MAGE) from baseline to 14 weeks; and mean HbA1c level at 3 and 6 months. Results: Out of 110 patients enrolled, 101 patients (91.8%) (Met+SU+Voglibose: 73 and Met+Voglibose: 28) completed the study. There was a significant decrease in average number of glycemic excursions per day from baseline to day 14 in the Met+Sul+Voglibose group and to week 14 in the Met+Voglibose group. There was also a significant reduction in percent time spent above target glucose range from baseline to day 14 in both treatment groups and to week 14 in the Met+SU+Voglibose group. A significant reduction in mean PPG area under the curve, day and night time mean glucose levels, and mean FPG levels from baseline to day 14 was reported in both treatment groups. A significant reduction in night time glucose, and average MAGE and HbA1c levels was reported from baseline to week 14 in the Met+Voglibose group and the Met+SU+Voglibose group, respectively. At 6 months, body weight, glucose levels, cholesterol, low-density lipoprotein-cholesterol, and HbA1c were significantly lower, especially in the Met+SU+Voglibose arm. Conclusion: Voglibose was useful in reducing glycemic variability and improving glycemic control in Asian Indian adults with T2DM. (CTRI/2018/04/013074).

Head-to-Head Comparison of the Hypoglycemic Efficacy and Safety Between Dipeptidyl Peptidase-4 Inhibitors and α-Glucosidase Inhibitors in Patients With Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trials

Background: The α-glucosidase inhibitors (AGIs) are commonly prescribed in Asian patients with type 2 diabetes mellitus (T2DM), but with a high incidence of gastrointestinal side effects. This study was aimed to compare the efficacy and safety of dipeptidyl peptidase-4 (DPP4) inhibitors and AGIs in T2DM patients in a meta-analysis.

Methods: Randomized controlled trials were identified via systematic search of PubMed, Embase, and Cochrane’s Library databases from inception to February, 2019. Meta-analyses were performed via a random or a fixed effect model according to the heterogeneity.

Results: Eighteen studies with a total of 4,051 patients with T2DM were included. The DPP4 inhibitors were associated with lower reduction of glycosylated hemoglobin (HbA1c) as compared with AGIs [weighed mean difference (WMD): −0.37%, p < 0.001]. Subgroup analyses indicated that the benefit of DPP4 inhibitors as compared with AGIs on HbA1c were independent of study design, scale, baseline HbA1c, with or without concurrent medications, or follow-up durations. Moreover, compared to AGIs, DPP4 inhibitors was associated with lower reductions of fasting blood glucose (WMD: −0.53 mmol/L, P < 0.001) and postprandial glucose at 2h (WMD: −0.60 mmol/L, P = 0.04), moderately increased body weight (WMD: 0.34 kg, P = 0.02), and decreased risk of gastrointestinal adverse events [risk ratio (RR): 0.48, P < 0.001], but unaffected risk of symptomatic hypoglycemia (RR: 0.96, P = 0.90).

Conclusions: The DPP4 inhibitors are superior to AGIs in T2DM patients for better glycemic control and lower risks of gastrointestinal side effects.

Effects of linagliptin versus voglibose on treatment-related quality of life in patients with type 2 diabetes: sub-analysis of the L-STEP study

Treatment-related quality of life (QOL) is an important aspect of diabetes management. However, no studies have compared the influence of dipeptidyl peptidase-4 inhibitors versus alpha-glucosidase inhibitors on treatment-related QOL. This prespecified sub-analysis of the Linagliptin Study of Effects on Postprandial blood glucose (L-STEP) compared the effects of linagliptin (5 mg once daily) and voglibose (0.2 mg/meal thrice daily) on treatment-related QOL in Japanese patients with type 2 diabetes (T2DM) inadequately controlled with diet and exercise therapy. Among 366 subjects in the original study, 182 in the linagliptin group and 173 in the voglibose group were included in this analysis. The outcome of this study was change in QOL as assessed by the Diabetes Therapy-Related Quality of Life 17 (DTR-QOL17) questionnaire from baseline to week 12. Compared with baseline data, total DTR-QOL17 scores were significantly higher after 12 weeks of linagliptin and voglibose treatment. The change in the total DTR-QOL17 score and the score of one domain, burden on social activities and daily activities, was significantly greater in the linagliptin group than in the voglibose group. In addition, only linagliptin treatment was identified as a factor associated with an increased total DTR-QOL17 score. Linagliptin is superior to voglibose in terms of improving treatment-related QOL in Japanese patients with T2DM.

Effects of linagliptin monotherapy compared with voglibose on postprandial lipid profiles in Japanese patients with type 2 diabetes: linagliptin study of effects on postprandial blood glucose (L-STEP) sub-study 1

Recently, we reported that linagliptin had equivalent efficacy to voglibose in reducing postprandial blood glucose levels in drug-naïve patients with type 2 diabetes (L-STEP Study). As a sub-study of the L-STEP Study we examined the effect of linagliptin on postprandial lipids profile. Between October 2012 and April 2014, the study enrolled patients with type 2 diabetes mellitus who had inadequate glycemic control. Patients were randomly assigned to either the linagliptin group (5 mg once daily, n = 85) or the voglibose group (0.2 mg/meal thrice daily, n = 71). Meal tolerance tests were performed at baseline (week 0) and endpoint (week 12). The increments in 4-h postprandial triglyceride, remnant lipoprotein cholesterol (RLP-C), and apolipoprotein B48 (ApoB48) from baseline to endpoint in the linagliptin group were lower (p < 0.001, p = 0.025 and p < 0.001). 4-h postprandial ApoB48 at endpoint was lower in the linagliptin group (p = 0.007), and positive correlation was detected between change of ApoB48 and changes in both triglyceride (r = 0.67, p < 0.001) and RLP-C (r = 0.73, p < 0.001) at 4 h. This study revealed that in drug-naïve Japanese patients with relatively mild type 2 diabetes mellitus, linagliptin improves not only postprandial blood glucose level but also levels of lipids such as TG and RLP-C by reducing the ApoB48 level compared with voglibose.

Postprandial hyperglycemia and postprandial hypertriglyceridemia in type 2 diabetes

Postprandial glucose level is an independent risk factor for cardiovascular disease that exerts effects greater than glucose levels at fasting state, whereas increase in serum triglyceride level, under both fasting and postprandial conditions, contributes to the development of arteriosclerosis. Insulin resistance is a prevailing cause of abnormalities in postabsorptive excursion of blood glucose and postprandial lipid profile. Excess fat deposition renders a vicious cycle of hyperglycemia and hypertriglyceridemia in the postprandial state, and both of which are contributors to atherosclerotic change of vessels especially in patients with type 2 diabetes mellitus. Several therapeutic approaches for ameliorating each of these abnormalities have been attempted, including various antidiabetic agents or new compounds targeting lipid metabolism.