Exploring the Possible Impact of Unbalanced Open-Label Drop-In of Glucose-Lowering Medications on EXSCEL Outcomes.

BACKGROUND: EXSCEL (Exenatide Study of Cardiovascular Event Lowering) assessed the impact of once-weekly exenatide 2 mg versus placebo in patients with type 2 diabetes mellitus, while aiming for glycemic equipoise. Consequently, greater drop-in of open-label glucose-lowering medications occurred in the placebo group. Accordingly, we explored the potential effects of their unbalanced use on major adverse cardiovascular events (MACE), defined as cardiovascular death, nonfatal myocardial infarction or nonfatal stroke, and all-cause mortality (ACM), given that some of these agents are cardioprotective. METHODS: Cox hazard models were performed by randomized treatment for drug classes where >5% open-label drop-in glucose-lowering medication occurred, and for glucagon-like peptide-1 receptor agonists (GLP-1 RAs; 3.0%) using three methodologies: drop-in visit right censoring, inverse probability for treatment weighting (IPTW), and applying drug class risk reductions. RESULTS: Baseline glucose-lowering medications for the 14 752 EXSCEL participants (73.1% with previous cardiovascular disease) did not differ between treatment groups. During median 3.2 years follow-up, open-label drop-in occurred in 33.4% of participants, more frequently with placebo than exenatide (38.1% versus 28.8%), with metformin (6.1% versus 4.9%), sulfonylurea (8.7% versus 6.9%), dipeptidyl peptidase-4 inhibitors (10.6% versus 7.5%), SGLT-2i (10.3% versus 8.1%), GLP-1 RA (3.4% versus 2.4%), and insulin (13.8% versus 9.4%). The MACE effect size was not altered meaningfully by right censoring, but the favorable HR for exenatide became nominally significant in the sulfonylurea and any glucose-lowering medication groups, while the ACM HR and p-values were essentially unchanged. IPTW decreased the MACE HR from 0.91 (P=0.061) to 0.85 (P=0.008) and the ACM HR from 0.86 (P=0.016) to 0.81 (P=0.012). Application of literature-derived risk reductions showed no meaningful changes in MACE or ACM HRs or P values, although simulations of substantially greater use of drop-in cardioprotective glucose-lowering agents demonstrated blunting of signal detection. CONCLUSIONS: EXSCEL-observed HRs for MACE and ACM remained robust after right censoring or application of literature-derived risk reductions, but the exenatide versus placebo MACE effect size and statistical significance were increased by IPTW. Effects of open-label drop-in cardioprotective medications need to be considered carefully when designing, conducting, and analyzing cardiovascular outcome trials of glucose-lowering agents under the premise of glycemic equipoise. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01144338.

Effect of Once-Weekly Exenatide in Patients With Type 2 Diabetes Mellitus With and Without Heart Failure and Heart Failure-Related Outcomes: Insights From the EXSCEL Trial.

BACKGROUND: Once-weekly exenatide (EQW) had a neutral effect on hospitalization for heart failure (HHF) in the EXSCEL study (Exenatide Study of Cardiovascular Event Lowering), with no differential treatment effect on major adverse cardiac events by baseline heart failure (HF) status. EQW's effects on secondary end points based on HHF status have not been reported. The objective was to explore the effects of EQW on secondary end points in patients with and without baseline HF and test the effects of EQW on recurrent HHF events. METHODS: The prespecified analysis of the randomized controlled EXSCEL trial, which enrolled patients with type 2 diabetes mellitus with and without additional cardiovascular disease, analyzed EQW effects on all-cause death, each major adverse cardiac event component, first HHF, and repeat HHF, by baseline HF status (regardless of ejection fraction). A subgroup analysis of the population stratified by preserved or reduced baseline ejection fraction was performed. RESULTS: Of 14 752 EXSCEL participants, 2389 (16.2%) had HF at baseline. Compared with those without HF at baseline, patients with preexisting HF were older, and more likely to be male and white, with a higher burden of other cardiovascular diseases. Overall, those assigned to EQW had a lower incidence of all-cause death (hazard ratio [HR], 0.86 [95% CI, 0.77-0.97]) and the composite outcome of all-cause death or HHF (HR, 0.89 [95% CI, 0.80-0.99]). When stratified by presence or absence of baseline HF, there was no observed reduction in all-cause death with EQW with baseline HF (HR, 1.05 [95% CI, 0.85-1.29]), while the risk of mortality was reduced with EQW in the no-HF group (HR, 0.79 [95% CI, 0.68-0.92]) with an interaction P value of 0.031. The reduction in all-cause death or HHF seen with EQW in patients without baseline HF (HR, 0.81 [95% CI, 0.71-0.93]) was not seen in patients with baseline HF (HR, 1.07 [95% CI, 0.89-1.29]; interaction P=0.015). First, plus recurrent, HHF was reduced in the exenatide group versus placebo (HR, 0.82 [95% CI, 0.68-0.99]; P=0.038). CONCLUSIONS: In EXSCEL, the use of EQW in patients with or without HF was well tolerated, but benefits of EQW on reduction in all-cause death and first hospitalization for HF were attenuated in patients with baseline HF. CLINICAL TRIAL REGISTRATION: https://www.clinicaltrials.gov. Unique identifier: NCT01144338.

Effects of Once-Weekly Exenatide on Cardiovascular Outcomes in Type 2 Diabetes.

BACKGROUND: The cardiovascular effects of adding once-weekly treatment with exenatide to usual care in patients with type 2 diabetes are unknown. METHODS: We randomly assigned patients with type 2 diabetes, with or without previous cardiovascular disease, to receive subcutaneous injections of extended-release exenatide at a dose of 2 mg or matching placebo once weekly. The primary composite outcome was the first occurrence of death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke. The coprimary hypotheses were that exenatide, administered once weekly, would be noninferior to placebo with respect to safety and superior to placebo with respect to efficacy. RESULTS: In all, 14,752 patients (of whom 10,782 [73.1%] had previous cardiovascular disease) were followed for a median of 3.2 years (interquartile range, 2.2 to 4.4). A primary composite outcome event occurred in 839 of 7356 patients (11.4%; 3.7 events per 100 person-years) in the exenatide group and in 905 of 7396 patients (12.2%; 4.0 events per 100 person-years) in the placebo group (hazard ratio, 0.91; 95% confidence interval [CI], 0.83 to 1.00), with the intention-to-treat analysis indicating that exenatide, administered once weekly, was noninferior to placebo with respect to safety (P<0.001 for noninferiority) but was not superior to placebo with respect to efficacy (P=0.06 for superiority). The rates of death from cardiovascular causes, fatal or nonfatal myocardial infarction, fatal or nonfatal stroke, hospitalization for heart failure, and hospitalization for acute coronary syndrome, and the incidence of acute pancreatitis, pancreatic cancer, medullary thyroid carcinoma, and serious adverse events did not differ significantly between the two groups. CONCLUSIONS: Among patients with type 2 diabetes with or without previous cardiovascular disease, the incidence of major adverse cardiovascular events did not differ significantly between patients who received exenatide and those who received placebo. (Funded by Amylin Pharmaceuticals; EXSCEL ClinicalTrials.gov number, NCT01144338 .).

Efficacy and tolerability of the new autoinjected suspension of exenatide once weekly versus exenatide twice daily in patients with type 2 diabetes.

AIMS: To simplify administration of aqueous exenatide once weekly, which requires reconstitution, the exenatide microspheres have been reformulated in a ready-to-use autoinjector with a Miglyol diluent (exenatide QWS-AI). This study compared the efficacy and safety of exenatide QWS-AI with the first-in-class glucagon-like peptide-1 receptor agonist exenatide twice daily (BID). MATERIALS AND METHODS: This randomized, open-label, controlled study in patients with type 2 diabetes using diet and exercise or taking stable oral glucose-lowering medication randomized patients 3:2 to either exenatide QWS-AI (2 mg) or exenatide BID (10 µg) for 28 weeks. The primary outcome was the 28-week change in glycated haemoglobin (HbA1c). A subset of patients completed a standardized meal test for postprandial and pharmacokinetic assessments. RESULTS: A total of 375 patients (mean HbA1c, 8.5% [69 mmol/mol]; body mass index, 33.2 kg/m2 ; diabetes duration, 8.5 years) received either exenatide QWS-AI (n = 229) or exenatide BID (n = 146); HbA1c was reduced by -1.4% and -1.0%, respectively (least-squares mean difference, -0.37%; P = .0072). More patients achieved HbA1c <7.0% with exenatide QWS-AI (49.3%) than with exenatide BID (43.2%; P = .225). Body weight was reduced in both groups (P = .37 for difference). Gastrointestinal adverse events (AEs) were reported in 22.7% (exenatide QWS-AI) and 35.6% (exenatide BID) of patients; fewer patients in the exenatide QWS-AI group withdrew because of AEs than in the exenatide BID group. Minor hypoglycaemia occurred most often with concomitant sulfonylurea use. CONCLUSIONS: Exenatide QWS-AI was associated with a greater reduction in HbA1c, similar weight loss and a favorable gastrointestinal AE profile compared with exenatide BID.

Effects of exenatide once weekly plus dapagliflozin, exenatide once weekly, or dapagliflozin, added to metformin monotherapy, on body weight, systolic blood pressure, and triglycerides in patients with type 2 diabetes in the DURATION-8 study.

This post hoc analysis assessed the effects on cardiovascular risk factors of body weight, systolic blood pressure (SBP) and triglycerides after 28 weeks' treatment with exenatide once weekly plus dapagliflozin, as compared with exenatide once weekly or dapagliflozin, in patient subpopulations from the DURATION-8 trial of patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin alone. Subgroups of patients were stratified according to their baseline body weight, SBP and triglyceride levels. Body weight, SBP and triglyceride levels were reduced across most respective subgroups, with no significant subgroup-by-treatment interactions. For each treatment, weight loss was numerically greater as baseline body mass index increased. SBP reductions were greater among patients with SBP ≥140 vs <140 mm Hg for exenatide once weekly plus dapagliflozin and exenatide once weekly. Reductions in triglyceride levels were greater among patients with baseline triglycerides <1.69 vs ≥1.69 mmol/L for each treatment. The combination of exenatide once weekly plus dapagliflozin reduced cardiovascular risk factors across baseline subgroups for each variable to a greater extent than did either individual drug; the greatest effects were observed in the high baseline subgroups for body weight and SBP.

Effects of exenatide once weekly plus dapagliflozin, exenatide once weekly alone, or dapagliflozin alone added to metformin monotherapy in subgroups of patients with type 2 diabetes in the DURATION-8 randomized controlled trial.

This analysis assessed whether responses with exenatide once weekly plus dapagliflozin (n = 231), exenatide once weekly alone (n = 230), or dapagliflozin alone (n = 233) differed in key patient subpopulations of the DURATION-8 trial. Potential treatment-by-subgroup interactions for changes in glycated haemoglobin (HbA1c) and body weight after 28 weeks were evaluated among subgroups determined by baseline HbA1c, age, sex, body mass index, type 2 diabetes duration, race, ethnicity and estimated glomerular filtration rate (eGFR). Exenatide once weekly plus dapagliflozin reduced HbA1c and body weight across all subgroups: least-squares mean reductions ranged from -8.4 to -26.1 mmol/mol (-0.77% to -2.39%) for HbA1c and from -2.07 to -4.55 kg for body weight. Potential treatment-by-subgroup interactions (P < .10) were found for HbA1c change by age (P = .016) and eGFR (P = .097). Age subgroup analysis findings were not consistent with expected mechanistic effects, with the small number of patients aged ≥65 years (n = 74 vs n = 499 for patients aged <65 years) limiting the interpretability of the interaction term. In the exenatide once weekly plus dapagliflozin and dapagliflozin groups, but not the exenatide once weekly group, HbA1c reductions were greater among patients with eGFR ≥90 vs ≥60 to <90 mL/min/1.73 m2 (least-squares mean reductions of -23.6 vs -19.0 mmol/mol [-2.16% vs -1.74%], -17.3 vs -12.0 mmol/mol [-1.58% vs -1.10%], and -17.7 vs -16.9 mmol/mol [-1.62% vs -1.55%] for the respective treatments); this was consistent with the mechanism of action of dapagliflozin. A potential treatment-by-subgroup interaction was observed for change in body weight by sex (P = .099), with greater weight loss for women vs men across all treatments (range -2.56 to -3.98 kg vs -0.56 to -2.99 kg). In conclusion, treatment with exenatide once weekly plus dapagliflozin reduced HbA1c and body weight across all patient subgroups and was more effective than exenatide once weekly or dapagliflozin alone in all adequately sized subgroups.

Effectiveness and tolerability of therapy with exenatide once weekly vs basal insulin among injectable-drug-naïve elderly or renal impaired patients with type 2 diabetes in the United States.

AIM: To evaluate the effectiveness and tolerability of exenatide once weekly (EQW) compared with basal insulin (BI) among injectable-drug-naïve patients with type 2 diabetes mellitus (T2DM) who are elderly or have renal impairment (RI). MATERIALS AND METHODS: Initiators of EQW and BI with T2DM were identified for the period 2012 to 2015 within a US electronic health record database and matched by propensity score. Matched EQW and BI initiators aged ≥65 years or who had RI were compared. Data on weight, glycated haemoglobin (HbA1c), estimated glomerular filtration rate (eGFR), blood pressure and lipids were obtained at baseline and quarterly (Q1-Q4) or semi-annually for 1 year after drug initiation. Hypoglycaemia and gastrointestinal symptoms were identified using diagnosis codes and data abstracted from clinical notes. RESULTS: Among patients aged ≥65 years, HbA1c changed by -0.50 and -0.31 percentage points from baseline to Q4 for EQW and BI initiators, respectively. Weight changed by -1.6 kg among EQW initiators compared with 0.2 kg among BI initiators. Compared with BI initiators, EQW initiators had a 1.45-fold increased risk of nausea and vomiting. Among patients with RI, HbA1c changed by -0.58 and -0.33 percentage points from baseline to Q4 for EQW and BI initiators, respectively. Weight changed by -1.9 kg for EQW initiators while BI initiators had no change in weight. EQW initiators had a 1.28-fold increased risk of constipation and diarrhoea compared with BI initiators. CONCLUSION: Regardless of age or renal function, the benefits of EQW relative to BI treatment are improved glycaemic control and increased weight loss, which should be weighed against the increased risk of gastrointestinal symptoms.

Baseline characteristics of patients enrolled in the Exenatide Study of Cardiovascular Event Lowering (EXSCEL).

BACKGROUND: EXSCEL is a randomized, double-blind, placebo-controlled trial examining the effect of exenatide once-weekly (EQW) versus placebo on time to the primary composite outcome (cardiovascular death, nonfatal myocardial infarction or nonfatal stroke) in patients with type 2 diabetes mellitus (DM) and a wide range of cardiovascular (CV) risk. METHODS: Patients were enrolled at 688 sites in 35 countries. We describe their baseline characteristics according to prior CV event status and compare patients with those enrolled in prior glucagon-like peptide-1 receptor agonist (GLP-1RA) outcomes trials. RESULTS: Of a total of 14,752 participants randomized between June 2010 and September 2015, 6,788 (46.0%) patients were enrolled in Europe; 3,708 (25.1%), North America; 2,727 (18.5%), Latin America; and 1,529 (10.4%), Asia Pacific. Overall, 73% had at least one prior CV event (70% coronary artery disease, 24% peripheral arterial disease, 22% cerebrovascular disease). The median (IQR) age was 63 years (56, 69), 38% were female, median baseline HbA1c was 8.0% (7.3, 8.9) and 16% had a prior history of heart failure. Those without a prior CV event were younger with a shorter duration of diabetes and better renal function than those with at least one prior CV event. Compared with prior GLP-1RA trials, EXSCEL has a larger percentage of patients without a prior CV event and a notable percentage who were taking a dipeptidyl peptidase-4 inhibitor at baseline (15%). CONCLUSIONS: EXSCEL is one of the largest global GLP-1RA trials, evaluating the safety and efficacy of EQW with a broad patient population that may extend generalizability compared to prior GLP-1RA trials (ClinicalTrials.gov number, NCT01144338).

Efficacy and safety of autoinjected exenatide once-weekly suspension versus sitagliptin or placebo with metformin in patients with type 2 diabetes: The DURATION-NEO-2 randomized clinical study.

AIMS: Glucagon-like peptide-1 receptor agonists and dipeptidyl peptidase-4 inhibitors treat type 2 diabetes through incretin-signaling pathways. This study compared the efficacy and safety of the glucagon-like peptide-1 receptor agonist exenatide once-weekly (Miglyol) suspension for autoinjection (QWS-AI) with the dipeptidyl peptidase-4 inhibitor sitagliptin or placebo. MATERIALS AND METHODS: In this open-label, multicentre study of patients with type 2 diabetes who had suboptimal glycaemic control on metformin monotherapy, 365 patients were randomized to receive exenatide 2.0 mg QWS-AI, sitagliptin 100 mg once daily or oral placebo (3:2:1 ratio). The primary endpoint was change in glycated hemoglobin (HbA1c) from baseline to 28 weeks. RESULTS: At 28 weeks, exenatide QWS-AI significantly reduced HbA1c from baseline compared to sitagliptin (-1.13% vs -0.75% [baseline values, 8.42% and 8.50%, respectively]; P = .02) and placebo (-0.40% [baseline value, 8.50%]; P = .001). More exenatide QWS-AI-treated patients achieved HbA1c <7.0% than did sitagliptin- or placebo-treated patients (43.1% vs 32.0% and 24.6%; both P < .05). Exenatide QWS-AI and sitagliptin reduced fasting plasma glucose from baseline to 28 weeks (-21.3 and -11.3 mg/dL) vs placebo (+9.6 mg/dL), with no significant difference between the 2 active treatments. Body weight decreased with both active treatments (-1.12 and -1.19 kg), but not with placebo (+0.15 kg). No improvement in blood pressure was observed in any group. The most common adverse events with exenatide QWS-AI were gastrointestinal events and injection-site reactions. CONCLUSIONS: This study demonstrated that exenatide QWS-AI reduced HbA1c more than sitagliptin or placebo and was well tolerated.

Saxagliptin and cardiovascular outcomes in patients with type 2 diabetes mellitus.

BACKGROUND: The cardiovascular safety and efficacy of many current antihyperglycemic agents, including saxagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, are unclear. METHODS: We randomly assigned 16,492 patients with type 2 diabetes who had a history of, or were at risk for, cardiovascular events to receive saxagliptin or placebo and followed them for a median of 2.1 years. Physicians were permitted to adjust other medications, including antihyperglycemic agents. The primary end point was a composite of cardiovascular death, myocardial infarction, or ischemic stroke. RESULTS: A primary end-point event occurred in 613 patients in the saxagliptin group and in 609 patients in the placebo group (7.3% and 7.2%, respectively, according to 2-year Kaplan-Meier estimates; hazard ratio with saxagliptin, 1.00; 95% confidence interval [CI], 0.89 to 1.12; P=0.99 for superiority; P<0.001 for noninferiority); the results were similar in the "on-treatment" analysis (hazard ratio, 1.03; 95% CI, 0.91 to 1.17). The major secondary end point of a composite of cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, coronary revascularization, or heart failure occurred in 1059 patients in the saxagliptin group and in 1034 patients in the placebo group (12.8% and 12.4%, respectively, according to 2-year Kaplan-Meier estimates; hazard ratio, 1.02; 95% CI, 0.94 to 1.11; P=0.66). More patients in the saxagliptin group than in the placebo group were hospitalized for heart failure (3.5% vs. 2.8%; hazard ratio, 1.27; 95% CI, 1.07 to 1.51; P=0.007). Rates of adjudicated cases of acute and chronic pancreatitis were similar in the two groups (acute pancreatitis, 0.3% in the saxagliptin group and 0.2% in the placebo group; chronic pancreatitis, <0.1% and 0.1% in the two groups, respectively). CONCLUSIONS: DPP-4 inhibition with saxagliptin did not increase or decrease the rate of ischemic events, though the rate of hospitalization for heart failure was increased. Although saxagliptin improves glycemic control, other approaches are necessary to reduce cardiovascular risk in patients with diabetes. (Funded by AstraZeneca and Bristol-Myers Squibb; SAVOR-TIMI 53 ClinicalTrials.gov number, NCT01107886.).

Rationale and design of the EXenatide Study of Cardiovascular Event Lowering (EXSCEL) trial.

Exenatide once-weekly is an extended release formulation of exenatide, a glucagon-like peptide-1 receptor agonist, which can improve glycemic control, body weight, blood pressure, and lipid levels in patients with type 2 diabetes mellitus (T2DM). The EXenatide Study of Cardiovascular Event Lowering (EXSCEL) will compare the impact of adding exenatide once-weekly to usual care with usual care alone on major cardiovascular outcomes. EXSCEL is an academically led, phase III/IV, double-blind, pragmatic placebo-controlled, global trial conducted in 35 countries aiming to enrol 14,000 patients with T2DM and a broad range of cardiovascular risk over approximately 5 years. Participants will be randomized (1:1) to receive exenatide once-weekly 2 mg or matching placebo by subcutaneous injections. The trial will continue until 1,360 confirmed primary composite cardiovascular end points, defined as cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke, have occurred. The primary efficacy hypothesis is that exenatide once-weekly is superior to usual care with respect to the primary composite cardiovascular end point. EXSCEL is powered to detect a 15% relative risk reduction in the exenatide once-weekly group, with 85% power and a 2-sided 5% alpha. The primary safety hypothesis is that exenatide once-weekly is noninferior to usual care with respect to the primary cardiovascular composite end point. Noninferiority will be concluded if the upper limit of the CI is <1.30. EXSCEL will assess whether exenatide once-weekly can reduce cardiovascular events in patients with T2DM with a broad range of cardiovascular risk. It will also provide long-term safety information on exenatide once-weekly in people with T2DM. ClinicalTrials.gov Identifier: NCT01144338.

Tesaglitazar, a dual PPAR-α/γ agonist, hamster carcinogenicity, investigative animal and clinical studies.

Tesaglitazar was developed as a dual peroxisome proliferator-activated receptor (PPARα/γ). To support the clinical program, a hamster carcinogenicity study was performed. The only neoplastic findings possibly related to treatment with tesaglitazar were low incidences of hemangioma and hemangiosarcoma in the liver of male animals. A high-power, two-year investigative study with interim necropsies was performed to further elucidate these findings. Treatment with tesaglitazar resulted in changes typical for exaggerated PPARα pharmacology in rodents, such as hepatocellular hypertrophy and hepatocellular carcinoma, but not an increased frequency of hemangiosarcomas. At the highest dose level, there was an increased incidence of sinusoidal dilatation and hemangiomas. No increased endothelial cell (EC) proliferation was detected in vivo, which was confirmed by in vitro administration to ECs. Immunohistochemistry and gene expression analyses indicated increased cellular stress and vascular endothelial growth factor (VEGF) expression in the liver, which may have contributed to the sinusoidal dilatation. A two-fold increase in the level of circulating VEGF was detected in the hamster at all dose levels, whereas no effect on VEGF was observed in patients treated with tesaglitazar. In conclusion, investigations have demonstrated that tesaglitazar does not produce hemangiosarcomas in hamster despite a slight effect on vascular morphology in the liver.

The design and rationale of the saxagliptin assessment of vascular outcomes recorded in patients with diabetes mellitus-thrombolysis in myocardial infarction (SAVOR-TIMI) 53 study.

OBJECTIVES: Saxagliptin, a dipeptidyl peptidase 4 inhibitor, improves glycemic control in patients with type 2 diabetes mellitus (T2DM) by increasing endogenous active, intact glucagon-like peptide 1 and glucose-dependent insulinotropic polypeptide in response to food, which augments insulin secretion and decreases glucagon release. RESEARCH DESIGN AND METHODS: SAVOR-TIMI 53 is a phase 4, randomized, double-blind, placebo-controlled trial conducted in 25 countries that is designed to evaluate the safety and efficacy of saxagliptin during long-term treatment of approximately 16,500 patients with T2DM. Eligible patients who are either treatment naive or on any background antidiabetic treatment (except incretin therapy) with history of established cardiovascular (CV) disease or multiple risk factors are randomized 1:1 to saxagliptin 5 mg QD (2.5 mg in subjects with moderate/severe renal impairment) or matching placebo, stratified by qualifying disease state. The primary end point is the composite of CV death, nonfatal myocardial infarction, or nonfatal ischemic stroke. The trial will continue until approximately 1,040 primary end points accrue, providing 85% power to identify a 17% relative reduction of the primary end point with saxagliptin versus placebo and 98% power to test for noninferiority of saxagliptin versus placebo (reject the upper limit of 95% CI for a hazard ratio <1.3 at a 1-sided α of .025). CONCLUSION: SAVOR-TIMI 53 is testing the hypothesis that treatment with saxagliptin is safe and reduces CV events in high-risk patients with T2DM.

Microvascular and Cardiovascular Outcomes According to Renal Function in Patients Treated With Once-Weekly Exenatide: Insights From the EXSCEL Trial.

OBJECTIVE: To evaluate the impact of once-weekly exenatide (EQW) on microvascular and cardiovascular (CV) outcomes by baseline renal function in the Exenatide Study of Cardiovascular Event Lowering (EXSCEL). RESEARCH DESIGN AND METHODS: Least squares mean difference (LSMD) in estimated glomerular filtration rate (eGFR) from baseline between the EQW and placebo groups was calculated for 13,844 participants. Cox regression models were used to estimate effects by group on incident macroalbuminuria, retinopathy, and major adverse CV events (MACE). Interval-censored time-to-event models estimated effects on renal composite 1 (40% eGFR decline, renal replacement, or renal death) and renal composite 2 (composite 1 variables plus macroalbuminuria). RESULTS: EQW did not change eGFR significantly (LSMD 0.21 mL/min/1.73 m2 [95% CI -0.27 to 0.70]). Macroalbuminuria occurred in 2.2% of patients in the EQW group and in 2.5% of those in the placebo group (hazard ratio [HR] 0.87 [95% CI 0.70-1.07]). Neither renal composite was reduced with EQW in unadjusted analyses, but renal composite 2 was reduced after adjustment (HR 0.85 [95% CI 0.74-0.98]). Retinopathy rates did not differ by treatment group or in the HbA1c-lowering or prior retinopathy subgroups. CV outcomes in those with eGFR <60 mL/min/1.73 m2 did not differ by group. Those with eGFR ≥60 mL/min/1.73 m2 had nominal risk reductions for MACE, all-cause mortality, and CV death, but interactions by renal function group were significant for only stroke (HR 0.74 [95% CI 0.58-0.93]; P for interaction = 0.035) and CV death (HR 1.08 [95% CI 0.85-1.38]; P for interaction = 0.031). CONCLUSIONS: EQW had no impact on unadjusted retinopathy or renal outcomes. CV risk was modestly reduced only in those with eGFR ≥60 mL/min/1.73 m2 in analyses unadjusted for multiplicity.

Changes in Serum Calcitonin Concentrations, Incidence of Medullary Thyroid Carcinoma, and Impact of Routine Calcitonin Concentration Monitoring in the EXenatide Study of Cardiovascular Event Lowering (EXSCEL).

OBJECTIVE: Increases in serum calcitonin, a tumor marker for medullary thyroid carcinoma (MTC), have been associated with glucagon-like peptide 1 receptor agonist use in some preclinical studies. We report calcitonin changes in exenatide-treated and placebo-administered participants and MTC incidence in the EXenatide Study of Cardiovascular Event Lowering (EXSCEL) and consider the impact of within-trial calcitonin monitoring. RESEARCH DESIGN AND METHODS: EXSCEL participants were randomized 1:1 to once-weekly exenatide 2 mg or placebo. Serum calcitonin was measured at baseline (with trial medication discontinued if >40 ng/L) and annually thereafter (with trial medication discontinued if ≥50 ng/L). Median calcitonin concentrations were calculated at each time point, and thyroid malignancies were collected prospectively. Data regarding follow-up after an elevated calcitonin were collected retrospectively. RESULTS: At baseline, 52 (30 exenatide and 22 placebo) participants had calcitonin >40 ng/L, and during follow-up an additional 23 participants (15 exenatide and 8 placebo) had calcitonin ≥50 ng/L in the intention-to-treat population. Median calcitonin concentrations were similar between treatment groups at baseline with no increase over time. Confirmed MTC occurred in three participants (2 exenatide and 1 placebo), all of whom had significantly elevated baseline calcitonin values (413, 422, and 655 ng/L). CONCLUSIONS: During a median 3.2 years' follow-up, no change in serum calcitonin was seen with exenatide therapy. The three confirmed cases of MTC all occurred in participants with markedly elevated baseline calcitonin levels, measured prior to trial medication administration. Regular calcitonin monitoring identified no additional cases of MTC, suggesting no benefit of routine calcitonin monitoring during exenatide treatment.

Safety and Efficacy of Exenatide Once Weekly Plus Dapagliflozin Once Daily Versus Exenatide or Dapagliflozin Alone in Patients With Type 2 Diabetes Inadequately Controlled With Metformin Monotherapy: 52-Week Results of the DURATION-8 Randomized Controlled Trial.

OBJECTIVE: Among patients with type 2 diabetes uncontrolled with metformin, exenatide once weekly (QW) plus dapagliflozin combination produced greater reductions in glycemia, weight, and systolic blood pressure (SBP) at 28 weeks than exenatide QW or dapagliflozin alone (DURATION-8). Here, we investigated the safety and maintenance of efficacy at 52 weeks, after a 24-week extension. RESEARCH DESIGN AND METHODS: This phase 3, multicenter, double-blind study randomized adults with type 2 diabetes (with glycated hemoglobin [HbA1c] 8.0-12.0% [64-108 mmol/mol] and on metformin ≥1,500 mg/day) to exenatide QW (2-mg subcutaneous injection) plus once-daily dapagliflozin (10-mg oral tablet), exenatide QW plus oral placebo, or dapagliflozin plus injected placebo. Extension-period P values were nominal. RESULTS: Of 1,375 patients screened, 695 were randomized (mean baseline HbA1c 9.3% [78 mmol/mol]); 81.2% completed the study, and 75.3% completed treatment. At 52 weeks, HbA1c reductions were greater with exenatide QW plus dapagliflozin (least squares mean change -1.75% [-19.1 mmol/mol]) versus exenatide QW (-1.38% [-15.1 mmol/mol]; P = 0.006) or dapagliflozin (-1.23% [-13.4 mmol/mol]; P < 0.001); mean HbA1c values were 6.9% (52 mmol/mol), 7.2% (55 mmol/mol), and 7.4% (57 mmol/mol), respectively. Weight and SBP reductions were greater with exenatide QW plus dapagliflozin (-3.31 kg and -4.5 mmHg) versus exenatide QW (-1.51 kg and -0.7 mmHg; both P < 0.001) but similar to those with dapagliflozin (-2.28 kg and -2.7 mmHg; P = 0.057 and P = 0.100, respectively). The exenatide QW plus dapagliflozin regimen was well tolerated with no unexpected safety findings; more patients treated with exenatide QW experienced gastrointestinal and injection site-related adverse events. No major hypoglycemia occurred. CONCLUSIONS: Among patients with type 2 diabetes uncontrolled with metformin, exenatide QW plus dapagliflozin provided sustained improvements in glycemia, weight, and SBP over 52 weeks, with no unexpected safety findings.

Control of Postprandial Hyperglycemia in Type 1 Diabetes by 24-Hour Fixed-Dose Coadministration of Pramlintide and Regular Human Insulin: A Randomized, Two-Way Crossover Study.

OBJECTIVE: Healthy pancreatic ß-cells secrete the hormones insulin and amylin in a fixed ratio. Both hormones are lacking in type 1 diabetes, and postprandial glucose control using insulin therapy alone is difficult. This study tested the pharmacodynamic effects of the amylin analog pramlintide and insulin delivered in a fixed ratio over a 24-h period. RESEARCH DESIGN AND METHODS: Patients with type 1 diabetes were stabilized on insulin pump therapy with insulin lispro before a randomized, single-masked, two-way crossover, 24-h inpatient study in which regular human insulin was administered with pramlintide or placebo using separate infusion pumps in a fixed ratio (9 µg/unit). Meal content and timing and patient-specific insulin doses were the same with each treatment. The primary outcome measure was change in mean glucose by continuous glucose monitoring (CGM). Profiles of laboratory-measured glucose, insulin, glucagon, and triglycerides were also compared. RESULTS: Mean 24-h glucose measured by CGM was lower with pramlintide versus placebo (8.5 vs. 9.7 mmol/L, respectively; P = 0.012) due to a marked reduction of postprandial increments. Glycemic variability was reduced, and postprandial glucagon and triglycerides were also lower with pramlintide versus placebo. Gastrointestinal side effects were more frequent during use of pramlintide; no major hypoglycemic events occurred with pramlintide or placebo. CONCLUSIONS: Coadministration of fixed-ratio pramlintide and regular human insulin for 24 h improved postprandial hyperglycemia and glycemic variability in patients with type 1 diabetes. Longer studies including dose titration under daily conditions are needed to determine whether this regimen could provide long-term improvement of glycemic control.

Effect of Once-Weekly Exenatide on Clinical Outcomes According to Baseline Risk in Patients With Type 2 Diabetes Mellitus: Insights From the EXSCEL Trial.

Background In the EXSCEL (Exenatide Study of Cardiovascular Event Lowering), exenatide once-weekly resulted in a nonsignificant reduction in major adverse cardiovascular events ( MACEs ) and a nominal 14% reduction in all-cause mortality in 14 752 patients with type 2 diabetes mellitus (T2 DM ) with and without cardiovascular disease. Whether patients at increased risk for events experienced a comparatively greater treatment benefit with exenatide is unknown. Methods and Results In the EXSCEL population, we created risk scores for MACEs and all-cause mortality using step-wise selection of baseline characteristics. A risk score was calculated for each patient, and a time-to-event model for each end point was developed including the risk score, treatment assignment, and risk-treatment interaction. Interaction P values evaluating for a differential treatment effect by baseline risk were reported. Over a median follow-up of 3.2 years (interquartile range, 2.2, 4.4), 1091 (7.4%) patients died and 1744 (11.8%) experienced a MACE . Independent predictors of MACEs and all-cause mortality included age, sex, comorbidities (eg, previous cardiovascular event), body mass index, blood pressure, hemoglobin A1c, and estimated glomerular filtration rate. The all-cause mortality and MACE risk models had modest discrimination with optimism-corrected c-indices of 0.73 and 0.71, respectively. No interaction was observed between treatment effect and risk profile for either end point (both interactions, P>0.1). Conclusions Baseline characteristics (eg, age, previous cardiovascular events) and routine laboratory values (eg, hemoglobin A1c, estimated glomerular filtration rate) provided modest prognostic value for mortality and MACEs in a broad population of patients with type 2 diabetes mellitus. Exenatide's effects on mortality and MACEs were consistent across the spectrum of baseline risk. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT 01144338.

Cardiovascular outcomes with glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes: a meta-analysis.

BACKGROUND: Glucagon-like peptide-1 (GLP-1) receptor agonists are effective glucose-lowering drugs. Findings from cardiovascular outcome trials showed cardiovascular safety of GLP-1 receptor agonists, but results for cardiovascular efficacy were varied. We aimed to examine overall cardiovascular efficacy for lixisenatide, liraglutide, semaglutide, and extended-release exenatide. METHODS: In this systematic review and meta-analysis, we analysed data from eligible trials that assessed the safety and efficacy of GLP-1 receptor agonists compared with placebo in adult patients (aged 18 years or older) with type 2 diabetes and had a primary outcome including, but not limited to, cardiovascular mortality, non-fatal myocardial infarction, and non-fatal stroke. We searched PubMed and MEDLINE without language restrictions up to Sept 18, 2017, for eligible trials. We did a meta-analysis of available trial data using a random-effects model to calculate overall hazard ratios (HRs) for cardiovascular efficacy outcomes and odds ratios for key safety outcomes. FINDINGS: Of 12 articles identified in our search and screened for eligibility, four trials of cardiovascular outcomes of GLP-1 receptor agonists were identified: ELIXA (lixisenatide), LEADER (liraglutide), SUSTAIN 6 (semaglutide), and EXSCEL (extended-release exenatide). Compared with placebo, GLP-1 receptor agonist treatment showed a significant 10% relative risk reduction in the three-point major adverse cardiovascular event primary outcome (cardiovascular mortality, non-fatal myocardial infarction, and non-fatal stroke; HR 0·90, 95% CI 0·82-0·99; p=0·033), a 13% RRR in cardiovascular mortality (0·87, 0·79-0·96; p=0·007), and a 12% relative risk reduction in all-cause mortality (0·88, 0·81-0·95; p=0·002), with low-to-moderate between-trial statistical heterogeneity. No significant effect of GLP-1 receptor agonists was identified on fatal and non-fatal myocardial infarction, fatal and non-fatal stroke, hospital admission for unstable angina, or hospital admission for heart failure. Overall, no significant differences were seen in severe hypoglycaemia, pancreatitis, pancreatic cancer, or medullary thyroid cancer reported between GLP-1 receptor agonist treatment and placebo. INTERPRETATION: Our findings show cardiovascular safety across all GLP-1 receptor agonist cardiovascular outcome trials and suggest that drugs in this class can reduce three-point major adverse cardiovascular events, cardiovascular mortality, and all-cause mortality risk, albeit to varying degrees for individual drugs, without significant safety concerns. GLP-1 receptor agonists have a favourable risk-benefit balance overall, which should allow the choice of drug to be individualised to each patient's needs. FUNDING: Amylin Pharmaceuticals (AstraZeneca).