Relative Contribution of Fasting and Postprandial Blood Glucose in Overall Glycemic Control: Post Hoc Analysis of a Phase IV Randomized Trial

DUAL II China: Superior HbA1c reductions and weight loss with insulin degludec/liraglutide (IDegLira) versus insulin degludec in a randomized trial of Chinese people with type 2 diabetes inadequately controlled on basal insulin

AIM

To assess the efficacy and safety of insulin degludec/liraglutide (IDegLira) versus insulin degludec (degludec) in Chinese people with type 2 diabetes (T2D) treated with basal insulin.

MATERIALS AND METHODS

In DUAL II China, a randomized, double-blinded, multicentre, treat-to-target trial, Chinese adults with T2D and HbA1c of 7.5% or more on basal insulin and metformin, with or without other oral antidiabetic drugs (OADs), were randomized 2:1 to 26 weeks of treatment with either IDegLira (max. dose 50 U degludec/1.8 mg liraglutide) or degludec (max. 50 U/day), respectively, combined with metformin. At 26 weeks, superiority of IDegLira over degludec was assessed for change in HbA1c (primary endpoint), and body weight and number of severe or blood glucose (BG)-confirmed hypoglycaemic episodes (confirmatory secondary endpoints).

RESULTS

Overall, 453 participants were randomized to IDegLira (n = 302) or degludec (n = 151). Superiority was confirmed for IDegLira over degludec in HbA1c change (-1.9% vs. -1.0%, respectively, estimated treatment difference [ETD] [95% confidence interval]: -0.92% [-1.09; -0.75], P < .0001), body weight change (-0.7 vs. +0.4 kg, respectively, ETD [95% CI]: -1.08 kg [-1.63; -0.52], P = .0002) and severe or BG-confirmed hypoglycaemia (estimated rate ratio [95% CI]: 0.53 [0.30; 0.94], P = .0297). The odds of achieving HbA1c less than 7.0% without hypoglycaemia and/or weight gain were greater with IDegLira than degludec (P < .0001 for all). Daily insulin dose at 26 weeks was lower for IDegLira (34.3 U) than degludec (37.4 U) (P = .0014). No unexpected safety signals were observed.

CONCLUSIONS

IDegLira may be an efficacious and well-tolerated treatment intensification option for Chinese people with T2D uncontrolled on basal insulin and OADs.

Efficacy of once-daily glucagon-like peptide-1 receptor agonist lixisenatide as an add-on treatment to basal insulin in Asian and white adults with type 2 diabetes mellitus: An individual-level pooled analysis of phase III studies

AIMS/INTRODUCTION

The prevalence and pathophysiological background of type 2 diabetes mellitus vary across ethnicities, and can affect treatment responses. Adding lixisenatide to basal insulin (BI) in type 2 diabetes mellitus patients has shown improvements in glycated hemoglobin (HbA1c) and postprandial glycemic (PPG) excursions, without increasing hypoglycemic events. We aim to compare the efficacy of lixisenatide in Asian and white patients inadequately controlled with basal insulin.

MATERIALS AND METHODS

An individual-level pooled analysis of two multi-national phase III studies, GetGoal-L and GetGoal-L-C, was carried out to assess the efficacy of lixisenatide versus placebo as an add-on treatment to BI ± metformin in Asian and white patients with type 2 diabetes mellitus. Change in HbA1c, 2-h PPG and PPG excursion were analyzed, along with possible predictors of glycemic control.

RESULTS

Pooled data showed that baseline characteristics were similar between Asian and white patients with the exception of bodyweight, body mass index and BI dose being higher in white patients. After 24 weeks, lixisenatide reduced HbA1c in both ethnic groups, with no statistically significant difference between the two groups (Asian patients least squares mean difference -0.49, 95% confidence interval -0.68 to - 0.30 and white patients least squares mean difference -0.45, 95% confidence interval -0.63 to - 0.26; P = 0.6287). Similarly, no significant difference was found in 2-h PPG reduction between both groups (least squares mean difference for Asian vs white patients: -3.37 vs -3.93; P = 0.3203). Treatment with lixisenatide contributed to HbA1c reduction of -0.56% after adjustment of baseline HbA1c level in Asian patients, and -0.41% in white patients.

CONCLUSIONS

Adding lixisenatide to BI significantly reduced HbA1c and 2-h PPG levels in both Asian and white participants with type 2 diabetes mellitus. No differences in treatment effect were observed between the two populations.

A new approach for investigating the relative contribution of basal glucose and postprandial glucose to HbA1C

To develop an accurate method for evaluating the relative contributions of basal glucose (BG) and postprandial glucose (PPG) to glycated haemoglobin (HbA1c) in subjects with hyperglycaemia using a Continuous Glucose Monitoring System (CGMS®). The subjects were divided into the normal glucose tolerance (NGT), impaired glucose tolerance (IGT), newly-diagnosed type 2 diabetes (NDDM), and drug-treated type 2 diabetes (T2DM) groups. We evaluated the relative contributions of BG and PPG to HbA1c in patients with hyperglycaemia according to three different baseline values. Subjects (n = 490) were grouped as follows: 92 NGT, 36 IGT, 131 NDDM, and 231 T2DM. The relative contributions of PPG to HbA1c were calculated using baseline values of 6.1 mmol/L, 5.6 mmol/L, and the 24-h glucose curve of the NGT group. The relative contribution of PPG to HbA1c decreased progressively from the IGT group to the T2DM group. Compared with the 24-h glucose curve as the baseline, the relative contribution of PPG was overestimated in 9.04% and 1.76% of the subjects when 6.1 mmol/L and 5.6 mmol/L were used as baselines, respectively (P < 0.01), in T2DM patients. The 24-h glucose curve of NGT is more suitable for studying the relative contributions of BG and PPG to HbA1c and it is more precise, as it considers physiological fluctuations in NGT after meals. However, 5.6 mmol/L can be used when the 24-h glucose curve for NGT is unavailable; using 6.1 mmol/L as a baseline value may overestimate the contribution to the HbA1c. There is no unified standard for assessing the contributions of basal glucose (BG) and postprandial glucose (PPG) to HbA1c. The 24-h glucose curve of NGT is more suitable for studying the relative contributions of BG and PPG to HbA1c, as it considers physiological fluctuations in NGT after meals. However, 5.6 mmol/L can be used when the 24-h glucose curve for NGT is unavailable; using 6.1 mmol/L as a baseline value may overestimate the contribution to the HbA1c.

Contribution of BHG and PPHG to Overall Hyperglycemia in T2DM Patients Treated with LM25 and LM50: Post Hoc Analysis of a Randomized Crossover Trial

INTRODUCTION

To investigate the relative contribution rates of basal hyperglycemia (BHG) and postprandial hyperglycemia (PPHG) to overall hyperglycemia in patients with type 2 diabetes mellitus (T2DM) treated with insulin lispro mix 25 and 50 (LM25 and LM50) as evaluated by continuous glucose monitoring (CGM).

METHODS

Eighty-one T2DM patients treated with premixed human insulin 70/30 (PHI70/30) were randomly divided into two groups and received a crossover protocol. In the first 16-week stage, one group received LM25 twice daily, the other group received LM50 twice daily. In the second 16-week stage, the two groups exchanged therapeutic regimen. Glycosylated hemoglobin (HbA_1c) measurement and CGM were performed at enrollment and at the end of each treatment stage.

RESULTS

BHG's contribution rate increased with increasing HbA_1c (from 34.5% to 60.8%). PPHG's contribution rates in the LM50 regimen were significantly lower than those in LM25 and PHI70/30 regimens at HbA_1c levels < 7.5%. Compared with LM50, LM25 shows a significant difference in reducing HbA_1c in the subgroup with baseline HbA_1c ≥ 8.5% (ΔHbA_1c LM25 vs. LM50 - 0.6 ± 0.1% vs. 0.3 ± 0.1%, p < 0.05).

CONCLUSIONS

For T2DM patients treated with premixed insulin analogues, postprandial hyperglycemia played a major role in the subgroup of patients with HbA_1c < 8.5%, while fasting hyperglycemia became the major contributor to overall hyperglycemia in the subgroup of patients with HbA_1c ≥ 8.5%.

TRIAL REGISTRATION

Chinese Clinical Trial Registry Identifier ChiCTR-TTRCC-12002516.

FUNDING

Lilly Suzhou Pharmaceutical Co., Ltd. (Shanghai Branch, China) and National Key Program of Clinical Science of China (WBYZ2011-873).