Exploring potential mediators of the cardiovascular benefit of dulaglutide in type 2 diabetes patients in REWIND.

BACKGROUND: The REWIND trial demonstrated cardiovascular (CV) benefits to patients with type 2 diabetes and multiple CV risk factors or established CV disease. This exploratory analysis evaluated the degree to which the effect of dulaglutide on CV risk factors could statistically account for its effects on major adverse cardiovascular events (MACE) in the REWIND trial. METHODS: Potential mediators of established CV risk factors that were significantly reduced by dulaglutide were assessed in a post hoc analysis using repeated measures mixed models and included glycated hemoglobin (HbA1c), body weight, waist-to-hip ratio, systolic blood pressure, low-density lipoprotein (LDL), and urine albumin/creatinine ratio (UACR). These factors, for which the change in level during follow-up was significantly associated with incident MACE, were identified using Cox regression modeling. Each identified variable was then included as a covariate in the Cox model assessing the effect of dulaglutide on MACE to estimate the degree to which the hazard ratio of dulaglutide vs placebo was attenuated. The combined effect of the variables associated with attenuation was assessed by including all variables in an additional Cox model. RESULTS: Although all evaluated variables were significantly improved by treatment, only changes in HbA1c and UACR were associated with MACE and a reduction in the effect of dulaglutide on this outcome was observed. The observed hazard ratio for MACE for dulaglutide vs placebo reduced by 36.1% by the updated mean HbA1c, and by 28.5% by the updated mean UACR. A similar pattern was observed for change from baseline in HbA1c and UACR and a reduction of 16.7% and 25.4%, respectively in the hazard ratio for MACE with dulaglutide vs placebo was observed. When HbA1c and UACR were both included, the observed hazard ratio reduced by 65.4% for the updated mean and 41.7% for the change from baseline with no HbA1c-UACR interaction (P interaction = 0.75 and 0.15, respectively). CONCLUSIONS: Treatment-induced improvement in HbA1c and UACR, but not changes in weight, systolic blood pressure, or LDL cholesterol, appear to partly mediate the beneficial effects of dulaglutide on MACE outcomes. These observations suggest that the proven effects of dulaglutide on cardiovascular disease benefit are partially related to changes in glycemic control and albuminuria, with residual unexplained benefit. Clinicaltrials.gov; Trial registration number: NCT01394952. URL: https://clinicaltrials.gov/ct2/show/NCT01394952.

Cardiovascular outcomes trials with glucagon-like peptide-1 receptor agonists: A comparison of study designs, populations and results.

Despite treatment advances leading to improved outcomes over the past 2 decades, cardiovascular (CV) disease (CVD) remains the leading cause of morbidity and mortality in people with diabetes. People with type 2 diabetes (T2D) have a 2- to 4-fold increased risk of CVD and CV death. Individuals with T2D have not seen the same improvements in CV morbidity and mortality as those without T2D. Given this, it is important to understand the CV impact of drugs used to treat T2D. In patients with T2D, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have shown a reduction in HbA1c and body weight regardless of their differences in chemical structure and pharmacokinetic variables. Glycaemic efficacy, accompanied by the potential for weight reduction and a low risk of hypoglycaemia, has moved GLP-1 RAs to the first treatment of choice following metformin monotherapy in the latest American Diabetes Association treatment guidelines. Additionally, all GLP-1 RAs have shown CV safety and several have proven CV benefit. GLP-1 RAs have been evaluated in cardiovascular outcomes trials (CVOTs) of varying sizes, designs and patient populations with differing reported effects on CV outcomes. The purpose of this article is to review the completed GLP-1 RA CVOTs with special attention to how their design, size, patient populations and conduct may influence the interpretation of results.

Relative contribution of basal and postprandial hyperglycaemia stratified by HbA1c categories before and after treatment intensification with dulaglutide.

AIM: To assess the effect of dulaglutide on the relative contribution of basal hyperglycaemia (BHG) and postprandial hyperglycaemia (PPHG) to overall hyperglycaemia across HbA1c categories in patients with type 2 diabetes. METHODS: Data from five phase 3 studies (N = 673) were pooled to assess the change in relative contributions of BHG and PPHG to overall hyperglycaemia across different HbA1c categories after 6 months of treatment intensification with dulaglutide 1.5 mg as monotherapy or with 1 or 2 oral medication(s) in patients with type 2 diabetes. BHG and PPHG were calculated using the area under the curve (AUC) of 7-point self-monitored plasma glucose concentration profiles. As a secondary objective, relative contribution of BHG and PPHG for dulaglutide versus liraglutide, exenatide BID and insulin glargine was assessed by individual studies at 6 months. RESULTS: In pooled data, after 6 months of treatment intensification with dulaglutide 1.5 mg, there was a significant reduction from baseline in overall hyperglycaemia (AUCoverall ) [(mean ± SE) -466.31 ± 18.32 mg*h/dL (P < 0.001)], BHG (AUCbasal ) [(mean ± SE) -371.46 ± 16.36 mg*h/dL (P < 0.001)] and PPHG (AUCpostprandial ) [(mean ± SE) -94.84 ± 7.97 mg*h/dL (P < 0.001)]. At baseline, relative contributions of BHG increased and PPHG decreased with increasing HbA1c levels. This pattern was maintained at 6 months, even as overall glycaemia improved with decreasing HbA1c values. CONCLUSIONS: In patients with type 2 diabetes, dulaglutide reduces HbA1c by lowering both basal and postprandial hyperglycaemia across various HbA1c levels.

Design and baseline characteristics of participants in the Researching cardiovascular Events with a Weekly INcretin in Diabetes (REWIND) trial on the cardiovascular effects of dulaglutide.

The aim was to determine the effects of dulaglutide, a synthetic once-weekly, injectable human glucagon-like peptide 1 analogue that lowers blood glucose, body weight, appetite and blood pressure, on cardiovascular outcomes. People with type 2 diabetes, aged ≥50 years, with glycated haemoglobin (HbA1c) ≤9.5%, and either a previous cardiovascular event, evidence of cardiovascular disease or ≥2 cardiovascular risk factors were randomly allocated to a weekly subcutaneous injection of either dulaglutide (1.5 mg) or placebo and followed within the ongoing Researching cardiovascular Events with a Weekly INcretin in Diabetes (REWIND) trial every 3 to 6 months. The primary cardiovascular outcome is the first occurrence of the composite of cardiovascular death or non-fatal myocardial infarction or non-fatal stroke. Secondary outcomes include each component of the primary composite cardiovascular outcome, a composite clinical microvascular outcome comprising retinal or renal disease, hospitalization for unstable angina, heart failure requiring hospitalization or an urgent heart failure visit, and all-cause mortality. Follow-up will continue until the accrual of 1200 confirmed primary outcomes. Recruitment of 9901 participants (mean age 66 years, 46% women) occurred in 370 sites located in 24 countries over a period of 2 years. The mean duration of diabetes was 10 years, mean baseline HbA1c was 7.3%, and 31% had prior cardiovascular disease. The REWIND trial's international scope, high proportion of women, high proportion of people without prior cardiovascular disease and inclusion of participants whose mean baseline HbA1c was 7.3% suggests that its cardiovascular and safety findings will be directly relevant to the typical middle-aged patient seen in general practice throughout the world.

Cardiovascular safety for once-weekly dulaglutide in type 2 diabetes: a pre-specified meta-analysis of prospectively adjudicated cardiovascular events.

BACKGROUND: Patients with type 2 diabetes (T2D) have a substantial increased risk for cardiovascular (CV) disease and associated mortality than those without diabetes. Dulaglutide is a once-weekly glucagon-like peptide-1 receptor agonist that is approved for treatment of T2D. METHODS: This meta-analysis evaluates the CV risk in patients with T2D treated with dulaglutide in 9 randomized safety and efficacy trials. Mean (median) treatment duration was 333 (358) days. Reported CV events were independently adjudicated by a treatment-blinded clinical endpoint committee. The primary measure was a 4-component major adverse CV event (4-component MACE) composite endpoint of death due to CV causes, nonfatal myocardial infarction (MI), nonfatal stroke, or hospitalization for unstable angina. Additional pre-specified endpoints included adjudicated coronary revascularizations, hospitalization for heart failure, and all-cause mortality. A Cox proportional hazards regression model (stratified by study) was used to estimate the hazard ratio (HR) and confidence interval (CI). Tests of treatment effects for the primary endpoint were conducted at a 2-sided alpha level of 0.0198 and a corresponding 98.02 % CI was calculated. Statistical heterogeneity between the strata (studies) was tested by including in the Cox model an interaction term between treatment and strata. RESULTS: The analysis included 6010 randomized patients [dulaglutide: 3885; comparator therapy (active or placebo): 2125]; cumulative exposure to dulaglutide or comparator therapy was 3941 and 2223 patient-years, respectively. The demographic and baseline CV disease characteristics were similar across groups. Twenty-six (0.67 %) patients in the dulaglutide group versus 25 (1.18 %) in the comparator group experienced a primary 4-component MACE (HR 0.57; adjusted 98.02 % CI 0.30, 1.10). Results for the 3-component MACE (composite endpoint of death due to CV causes, nonfatal MI or stroke), 6-component MACE (composite endpoint of death due to CV causes, nonfatal MI or stroke, hospitalization for unstable angina or heart failure, or coronary revascularizations) and all-cause mortality were consistent with the primary analysis (HR < 1.0 for all). CONCLUSIONS: These results suggest that dulaglutide does not increase the risk of major CV events in T2D patients. The ongoing CV outcomes study, Researching CV Events with a Weekly Incretin in Diabetes (REWIND), will further assess CV safety of dulaglutide.

Efficacy and Safety of Dulaglutide in Older Patients: A post hoc Analysis of the REWIND trial.

CONTEXT: Dulaglutide reduced major adverse cardiovascular events (MACE) in the Researching Cardiovascular Events with a Weekly INcretin in Diabetes (REWIND) trial. Its efficacy and safety in older vs younger patients have not been explicitly analyzed. OBJECTIVE: This work aimed to assess efficacy and safety of dulaglutide vs placebo in REWIND by age subgroups (≥ 65 and < 65 years). METHODS: A post hoc subgroup analysis of REWIND was conducted at 371 sites in 24 countries. Participants included type 2 diabetes patients aged 50 years or older with established cardiovascular (CV) disease or multiple CV risk factors, and a wide range of glycemic control. Patients were randomly assigned (1:1) to dulaglutide 1.5 mg or placebo as an add-on to country-specific standard of care. Main outcomes measures included MACE (first occurrence of the composite of nonfatal myocardial infarction, nonfatal stroke, or death from CV or unknown causes). RESULTS: There were 5256 randomly assigned patients who were 65 years or older (mean = 71.0), and 4645 were younger than 65 years (mean = 60.7). Baseline characteristics were similar in randomized treatment groups. Dulaglutide treatment showed a similar reduction in the incidence (11% vs 13%) of MACE in older vs younger patients. The rate of permanent study drug discontinuation, incidence of all-cause mortality, hospitalizations for heart failure, severe hypoglycemia, severe renal or urinary events, and serious gastrointestinal events were similar between randomized treatment groups within each age subgroup. The incidence rate of serious cardiac conduction disorders was numerically higher in the dulaglutide group compared to placebo within each age subgroup but the difference was not statistically significant. CONCLUSION: Dulaglutide had similar efficacy and safety in REWIND in patients65 years and older and those younger than 65 years.