Incorporating and interpreting regulatory guidance on estimands in diabetes clinical trials: The PIONEER 1 randomized clinical trial as an example

Regulatory guidelines describe the use of estimands in designing and conducting clinical trials. Estimands ensure alignment of the objectives with the design, conduct and analysis of a trial. An estimand is defined by four inter-related attributes: the population of interest, the variable (endpoint) of interest, the way intercurrent events are handled and the population level summary. A trial may employ multiple estimands to evaluate treatment effects from different perspectives in order to address different scientific questions. As estimands may be an unfamiliar concept for many clinicians treating diabetes, this paper reviews the estimand concept and uses the PIONEER 1 phase 3a clinical trial, which investigated the efficacy and safety of oral semaglutide vs placebo, as an example of the way in which estimands can be implemented and interpreted. In the PIONEER 1 trial, two estimands were employed for each efficacy endpoint and were labelled as: (a) the treatment policy estimand, used to assess the treatment effect regardless of use of rescue medication or discontinuation of trial product, and provides a broad perspective of the treatment effect in the population of patients with type 2 diabetes in clinical practice; and (b) the trial product estimand, used to assess the treatment effect if all patients had continued to use trial product for the planned duration of the trial without rescue medication, thereby providing information on the anticipated treatment effect of the medication. Both approaches are complementary to understanding the effect of the studied treatments.

Long-term Cost-effectiveness of Insulin Degludec Versus Insulin Glargine U100 in the UK: Evidence from the Basal-bolus Subgroup of the DEVOTE Trial (DEVOTE 16)

OBJECTIVES

To evaluate the cost-effectiveness of insulin degludec (degludec) versus insulin glargine 100 units/mL (glargine U100) in basal-bolus regimens for patients with type 2 diabetes (T2D) at high cardiovascular (CV) risk based on the DEVOTE CV outcomes trial.

METHODS

A microsimulation model, informed by clinical outcomes from the subgroup of patients using basal-bolus insulin therapy in DEVOTE (NCT01959529) and by the UKPDS Outcomes Model 2 risk equations, was used to model direct costs (2018 GBP) and effectiveness outcomes [quality-adjusted life years (QALYs)] with degludec versus glargine U100 over a 40-year time horizon. The model captured the development of eight diabetes-related complications, death, severe hypoglycemia and insulin dosing. This analysis was conducted from the perspective of National Health Service (NHS) England.

RESULTS

Treatment with degludec versus glargine U100 in basal-bolus regimens was associated with improved clinical outcomes at a higher cost per patient [incremental cost effectiveness ratio (ICER): £14,956 GBP/QALY]. Degludec remained cost effective versus glargine U100 in all exploratory sensitivity analyses, with ICERs below the widely accepted willingness-to-pay threshold, although the result was most sensitive to assumptions regarding the persistence of treatment effects.

CONCLUSIONS

Our long-term modeling analysis suggested that degludec was cost effective (from the perspective of NHS England) versus glargine U100 in basal-bolus regimens for patients with T2D at high CV risk. Our findings raise important questions regarding how to model the health economics of diabetes therapies.

Effects of Liraglutide Compared With Placebo on Events of Acute Gallbladder or Biliary Disease in Patients With Type 2 Diabetes at High Risk for Cardiovascular Events in the LEADER Randomized Trial

OBJECTIVE

To explore gallbladder- and biliary tract-related events reported for the liraglutide and placebo groups in the Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results (LEADER) trial.

RESEARCH DESIGN AND METHODS

LEADER was an international, randomized, double-blind, controlled cardiovascular (CV) outcomes trial. Participants with type 2 diabetes at high risk for CV events (n = 9,340) were randomized 1:1 to receive either liraglutide (≤1.8 mg daily; n = 4,668) or placebo (n = 4,672), with both groups also receiving standard care (treatment period: 3.5-5 years). Acute gallstone disease was a medical event of special interest. This post hoc analysis categorized captured events of acute gallbladder or biliary disease into four groups: uncomplicated gallbladder stones, complicated gallbladder stones, cholecystitis, and biliary obstruction. Time to first event by treatment group was analyzed using Cox regression.

RESULTS

There was an increased risk of acute gallbladder or biliary disease with liraglutide versus placebo (n = 141 of 4,668 vs. n = 88 of 4,672 patients, respectively; hazard ratio [HR] 1.60; 95% CI 1.23, 2.09; P < 0.001). Similar trends were observed for each of the four categories of gallbladder- or biliary tract-related events. Cholecystectomy was performed more frequently in liraglutide-treated patients (HR 1.56; 95% CI 1.10, 2.20; P = 0.013) but for similar proportions of the patients who experienced gallbladder- or biliary tract-related events (57% with liraglutide vs. 59% with placebo).

CONCLUSIONS

Although LEADER was not specifically designed to assess acute gallbladder or biliary disease, the trial showed an increased risk of gallbladder- or biliary tract-related events with liraglutide versus placebo, which appeared to be consistent across four categories of these events. Further studies should investigate the relevant mechanisms.

Initial injectable therapy in type 2 diabetes: Key considerations when choosing between glucagon-like peptide 1 receptor agonists and insulin

Managing type 2 diabetes is complex and necessitates careful consideration of patient factors such as engagement in self-care, comorbidities and costs. Since type 2 diabetes is a progressive disease, many patients will require injectable agents, usually insulin. Recent ADA-EASD guidelines recommend glucagon-like peptide 1 receptor agonists (GLP-1 RAs) as first injectable therapy in most cases. The basis for this recommendation is the similar glycemic efficacy of GLP-1 RAs and insulin, but with GLP-1 RAs promoting weight loss instead of weight gain, at lower hypoglycemia risk, and with cardiovascular benefits in patients with pre-existing cardiovascular disease. GLP-1 RAs also reduce burden of glucose self-monitoring. However, tolerability and costs are important considerations, and notably, rates of drug discontinuation are often higher for GLP-1 RAs than basal insulin. To minimize risk of gastrointestinal symptoms patients should be started on lowest doses of GLP-1 RAs and up-titrated slowly. Overall healthcare costs may be lower with GLP-1 RAs compared to insulin. Though patient-level costs may still be prohibitive, GLP-1 RAs can replace 50-80 units of insulin daily and reduce costs associated with glucose self-monitoring. Decisions regarding initiating injectable therapy should be individualized. This review provides a framework to guide decision-making in the real-world setting.

Study design choices for evaluating the comparative safety of diabetes medications: An evaluation of pioglitazone use and risk of bladder cancer in older US adults with type-2 diabetes

AIM

The aim of the study was to empirically demonstrate the effect of varying study designs when evaluating the safety of pioglitazone in treating bladder cancer.

METHODS

We identified Medicare beneficiaries above 65 years of age with diabetes between 2008 and 2015 and with classified exposure (at least two claims within 180 days) to glucose-lowering drugs (GLD), pioglitazone or another drug. The effects of varying the following study design parameters on bladder cancer risk were assessed: use of a new vs existing drug, choice of referent (all non-users and users of GLDs, non-insulin GLDs and DPP-4s) and whether or not censoring accounted for treatment change. We used the Cox proportional hazards model to obtain adjusted HRs and 95% CIs.

RESULTS

We included 1,510,212 patients classified as pioglitazone users (N = 135,188) or non-users (N = 1,375,024). Users had more diabetic complications than non-users, but fewer than insulin users. The HR ranged from 1.10 (1.01-1.20) to 1.13 (0.99-1.29) when censoring ignored treatment change, suggesting a weak association or none between pioglitazone and bladder cancer, probably under-estimating risk. However, the HR was 1.20 (1.01-1.42) when cohorts were restricted to new users, censored upon treatment change, and when DPP-4 was used as the referent, suggesting an increased risk of bladder cancer associated with pioglitazone.

CONCLUSIONS

The continued demand for new GLDs indicates the need for more robust observational methods to improve the value of generating real-world evidence in equipping clinicians to make informed prescribing decisions. Although there is no one-size-fits-all approach, we recommend active comparator new user study designs that compare therapeutically equivalent drugs and account for treatment changes during follow-up to present the least biased comparative safety estimates.

A Mixed-Methods, Randomized Clinical Trial to Examine Feasibility of a Mindfulness-Based Stress Management and Diabetes Risk Reduction Intervention for African Americans with Prediabetes

African Americans have disproportionately high rates of stress-related conditions, including diabetes and diabetes-related morbidity. Psychological stress may negatively influence engagement in risk-reducing lifestyle changes (physical activity and healthy eating) and stress-related physiology that increase diabetes risk. This study examined the feasibility of conducting a randomized trial comparing a novel mindfulness-based stress management program combined with diabetes risk-reduction education versus a conventional diabetes risk-reduction education program among African American adults with prediabetes and self-reported life stress. Participants were recruited in collaboration with community partners and randomized to the mindfulness-based diabetes risk-reduction education program for prediabetes (MPD; n = 38) or the conventional diabetes risk-reduction education program for prediabetes (CPD; n = 30). The mindfulness components were adapted from the Mindfulness-based Stress Reduction Program. The diabetes risk-reduction components were adapted from the Power to Prevent Program and the Diabetes Prevention Program. Groups met for eight weeks for 2.5 hours, with a half-day retreat and six-monthly boosters. Mixed-methods strategies were used to assess feasibility. Psychological, behavioral, and metabolic data were collected before the intervention and at three and six months postintervention to examine within-group change and feasibility of collecting such data in future clinical efficacy research. Participants reported acceptability, credibility, and cultural relevance of the intervention components. Enrollment of eligible participants (79%), intervention session attendance (76.5%), retention (90%), and postintervention data collection attendance (83%, 82%, and 78%, respectively) demonstrated feasibility, and qualitative data provided information to further enhance feasibility in future studies. Both groups exhibited an A1C reduction. MPD participants had reductions in perceived stress, BMI, calorie, carbohydrate and fat intake, and increases in spiritual well-being. Considering the high prevalence of diabetes and diabetes-related complications in African Americans, these novel findings provide promising guidance to develop a larger trial powered to examine efficacy of a mindfulness-based stress management and diabetes risk-reduction education program for African Americans with prediabetes.

A Genetic Locus on Chromosome 2q24 Predicting Peripheral Neuropathy Risk in Type 2 Diabetes: Results From the ACCORD and BARI 2D Studies

Genetic factors have been postulated to be involved in the etiology of diabetic peripheral neuropathy (DPN), but their identity remains mostly unknown. The aim of this study was to conduct a systematic search for genetic variants influencing DPN risk using two well-characterized cohorts. A genome-wide association study (GWAS) testing 6.8 million single nucleotide polymorphisms was conducted among participants of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) clinical trial. Included were 4,384 white case patients with type 2 diabetes (T2D) and prevalent or incident DPN (defined as a Michigan Neuropathy Screening Instrument clinical examination score >2.0) and 784 white control subjects with T2D and no evidence of DPN at baseline or during follow-up. Replication of significant loci was sought among white subjects with T2D (791 DPN-positive case subjects and 158 DPN-negative control subjects) from the Bypass Angioplasty Revascularization Investigation in Type 2 Diabetes (BARI 2D) trial. Association between significant variants and gene expression in peripheral nerves was evaluated in the Genotype-Tissue Expression (GTEx) database. A cluster of 28 SNPs on chromosome 2q24 reached GWAS significance (P < 5 × 10-8) in ACCORD. The minor allele of the lead SNP (rs13417783, minor allele frequency = 0.14) decreased DPN odds by 36% (odds ratio [OR] 0.64, 95% CI 0.55-0.74, P = 1.9 × 10-9). This effect was not influenced by ACCORD treatment assignments (P for interaction = 0.6) or mediated by an association with known DPN risk factors. This locus was successfully validated in BARI 2D (OR 0.57, 95% CI 0.42-0.80, P = 9 × 10-4; summary P = 7.9 × 10-12). In GTEx, the minor, protective allele at this locus was associated with higher tibial nerve expression of an adjacent gene (SCN2A) coding for human voltage-gated sodium channel NaV1.2 (P = 9 × 10-4). To conclude, we have identified and successfully validated a previously unknown locus with a powerful protective effect on the development of DPN in T2D. These results may provide novel insights into DPN pathogenesis and point to a potential target for novel interventions.

Identification of clinically relevant dysglycemia phenotypes based on continuous glucose monitoring data from youth with type 1 diabetes and elevated hemoglobin A1c

BACKGROUND/OBJECTIVE

To identify and characterize subgroups of adolescents with type 1 diabetes (T1D) and elevated hemoglobin A1c (HbA1c) who share patterns in their continuous glucose monitoring (CGM) data as "dysglycemia phenotypes."

METHODS

Data were analyzed from the Flexible Lifestyles Empowering Change randomized trial. Adolescents with T1D (13-16 years, duration >1 year) and HbA1c 8% to 13% (64-119 mmol/mol) wore blinded CGM at baseline for 7 days. Participants were clustered based on eight CGM metrics measuring hypoglycemia, hyperglycemia, and glycemic variability. Clusters were characterized by their baseline features and 18 months changes in HbA1c using adjusted mixed effects models. For comparison, participants were stratified by baseline HbA1c (≤/>9.0% [75 mmol/mol]).

RESULTS

The study sample included 234 adolescents (49.8% female, baseline age 14.8 ± 1.1 years, baseline T1D duration 6.4 ± 3.7 years, baseline HbA1c 9.6% ± 1.2%, [81 ± 13 mmol/mol]). Three Dysglycemia Clusters were identified with significant differences across all CGM metrics (P < .001). Dysglycemia Cluster 3 (n = 40, 17.1%) showed severe hypoglycemia and glycemic variability with moderate hyperglycemia and had a lower baseline HbA1c than Clusters 1 and 2 (P < .001). This cluster showed increases in HbA1c over 18 months (p-for-interaction = 0.006). No other baseline characteristics were associated with Dysglycemia Clusters. High HbA1c was associated with lower pump use, greater insulin doses, more frequent blood glucose monitoring, lower motivation, and lower adherence to diabetes self-management (all P < .05).

CONCLUSIONS

There are subgroups of adolescents with T1D for which glycemic control is challenged by different aspects of dysglycemia. Enhanced understanding of demographic, behavioral, and clinical characteristics that contribute to CGM-derived dysglycemia phenotypes may reveal strategies to improve treatment.

Cardiovascular safety and lower severe hypoglycaemia of insulin degludec versus insulin glargine U100 in patients with type 2 diabetes aged 65 years or older: Results from DEVOTE (DEVOTE 7)

AIMS

The aim of this study was to describe the risks of cardiovascular (CV) events and severe hypoglycaemia with insulin degludec (degludec) vs insulin glargine 100 units/mL (glargine U100) in patients with type 2 diabetes (T2D) aged 65 years or older.

MATERIALS AND METHODS

A total of 7637 patients in the DEVOTE trial, a treat-to-target, randomized, double-blind trial evaluating the CV safety of degludec vs glargine U100, were divided into three age groups (50-64 years, n = 3682; 65-74 years, n = 3136; ≥75 years, n = 819). Outcomes by overall age group and randomized treatment differences were analysed for major adverse cardiovascular events (MACE), all-cause mortality, severe hypoglycaemia and serious adverse events (SAEs).

RESULTS

Patients with increasing age had higher risks of CV death, all-cause mortality and SAEs, and there were non-significant trends towards higher risks of MACE and severe hypoglycaemia. Treatment effects on the risk of MACE, all-cause mortality, severe hypoglycaemia and SAEs were consistent across age groups, based on the non-significant interactions between treatment and age with regard to these outcomes.

CONCLUSIONS

There were higher risks of CV death, all-cause mortality and SAEs, and trends towards higher risks of MACE and severe hypoglycaemia with increasing age after adjusting for baseline differences. The effects across age groups of degludec vs glargine U100 on MACE, all-cause mortality and severe hypoglycaemia were comparable, suggesting that the risk of MACE, as well as all-cause mortality, is similar and the risk of severe hypoglycaemia is lower with degludec regardless of age. Evidence is conclusive only until 74 years of age.

Duration of diabetes and cardiorenal efficacy of liraglutide and semaglutide: A post hoc analysis of the LEADER and SUSTAIN 6 clinical trials

Cardiovascular risk reduction with liraglutide and semaglutide in patients with type 2 diabetes was demonstrated in the LEADER (ClinicalTrials.gov: NCT01179048) and SUSTAIN 6 (ClinicalTrials.gov: NCT01720446) cardiovascular outcome trials. This post hoc analysis assessed the impact of diabetes duration (<5, 5 to <15, 15 to <25 and ≥25 years at baseline) on cardiorenal efficacy of these human glucagon-like peptide-1 analogues using a Cox proportional hazards model. Proportions of patients in the LEADER trial across diabetes duration strata were 15% (<5 years, n = 1377), 50% (5 to <15 years, n = 4692), 27% (15 to <25 years, n = 2504) and 8% (≥25 years, n = 748); corresponding proportions in the SUSTAIN-6 trial were 13% (<5 years, n = 422), 48% (5 to <15 years, n = 1582), 30% (15 to <25 years, n = 977) and 10% (≥25 years, n = 316). Overall, longer diabetes duration was associated with higher age; higher prevalence of females; history of ischaemic stroke, peripheral arterial disease and insulin use; and inferior renal function. There was an increased frequency of major adverse cardiovascular events (MACE), expanded MACE and nephropathy events with increasing diabetes duration. Liraglutide and semaglutide consistently reduced the risk of cardiorenal outcomes across categories of diabetes duration (P-interaction was not significant for all endpoints analysed).

Charge-switchable polymeric complex for glucose-responsive insulin delivery in mice and pigs

Glucose-responsive insulin delivery systems with robust responsiveness that has been validated in animal models, especially in large animal models, remain elusive. Here, we exploit a new strategy to form a micro-sized complex between a charge-switchable polymer with a glucose-sensing moiety and insulin driven by electrostatic interaction. Both high insulin loading efficiency (95%) and loading capacity (49%) can be achieved. In the presence of a hyperglycemic state, the glucose-responsive phenylboronic acid (PBA) binds glucose instantly and converts the charge of the polymeric moiety from positive to negative, thereby enabling the release of insulin from the complex. Adjusting the ratio of the positively charged group to PBA achieves inhibited insulin release from the complex under normoglycemic conditions and promoted release under hyperglycemic conditions. Through chemically induced type 1 diabetic mouse and swine models, in vivo hyperglycemia-triggered insulin release with fast response is demonstrated after the complex is administrated by either subcutaneous injection or transdermal microneedle array patch.

Efficacy and safety of oral semaglutide with flexible dose adjustment versus sitagliptin in type 2 diabetes (PIONEER 7): a multicentre, open-label, randomised, phase 3a trial

BACKGROUND

Oral semaglutide is the first oral formulation of a glucagon-like peptide-1 (GLP-1) receptor agonist developed for the treatment of type 2 diabetes. We aimed to compare the efficacy and safety of flexible dose adjustments of oral semaglutide with sitagliptin 100 mg.

METHODS

In this 52-week, multicentre, randomised, open-label, phase 3a trial, we recruited patients with type 2 diabetes from 81 sites in ten countries. Patients were eligible if they were aged 18 years or older (19 years or older in South Korea), had type 2 diabetes (diagnosed ≥90 days before screening), HbA_1c of 7·5-9·5% (58-80 mmol/mol), and were inadequately controlled on stable daily doses of one or two oral glucose-lowering drugs (for 90 days or more before screening). Participants were randomly assigned (1:1) by use of an interactive web-response system, stratified by background glucose-lowering medication at screening, to oral semaglutide with flexible dose adjustments to 3, 7, or 14 mg once daily or sitagliptin 100 mg once daily. To approximate treatment individualisation in clinical practice, oral semaglutide dose could be adjusted on the basis of prespecified HbA_1c and tolerability criteria. Two efficacy-related estimands were prespecified: treatment policy (regardless of treatment discontinuation or use of rescue medication) and trial product (on treatment and without use of rescue medication) for participants randomly assigned to treatment. The primary endpoint was achievement of HbA_1c of less than 7% (53 mmol/mol) at week 52 and the confirmatory secondary efficacy endpoint was change in bodyweight from baseline to week 52. Safety was assessed in all participants who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT02849080, and European Clinical Trials Database, EudraCT number 2015-005593-38, and an open-label extension is ongoing.

FINDINGS

Between Sept 20, 2016, and Feb 7, 2017, of 804 patients assessed for eligibility, 504 were eligible and randomly assigned to oral semaglutide (n=253) or sitagliptin (n=251). Most participants were male (285 [57%] of 504) with a mean age of 57·4 years (SD 9·9). All participants were given at least one dose of their allocated study drug except for one participant in the sitagliptin group. From a mean baseline HbA_1c of 8·3% (SD 0·6%; 67 mmol/mol [SD 6·4]), a greater proportion of participants achieved an HbA_1c of less than 7% with oral semaglutide than did with sitagliptin (treatment policy estimand: 58% [134 of 230] vs 25% [60 of 238]; and trial product estimand: 63% [123 of 196] vs 28% [52 of 184]). The odds of achieving an HbA_1c of less than 7% was significantly better with oral semaglutide than sitagliptin (treatment policy estimand: odds ratio [OR] 4·40, 95% CI 2·89-6·70, p<0·0001; and trial product estimand: 5·54, 3·54-8·68, p<0·0001). The odds of decreasing mean bodyweight from baseline to week 52 were higher with oral semaglutide than with sitagliptin (estimated mean change in bodyweight, treatment policy estimand: -2·6 kg [SE 0·3] vs -0·7 kg [SE 0·2], estimated treatment difference [ETD] -1·9 kg, 95% CI -2·6 to -1·2; p<0·0001; and trial product estimand: -2·9 kg [SE 0·3] vs -0·8 kg [SE 0·3], ETD -2·2 kg, -2·9 to -1·5; p<0·0001). Adverse events occurred in 197 (78%) of 253 participants in the oral semaglutide group versus 172 (69%) of 250 in the sitagliptin group, and nausea was the most common adverse event with oral semaglutide (53 [21%]). Two deaths occurred in the sitagliptin group during the trial.

INTERPRETATION

Oral semaglutide, with flexible dose adjustment, based on efficacy and tolerability, provided superior glycaemic control and weight loss compared with sitagliptin, and with a safety profile consistent with subcutaneous GLP-1 receptor agonists.

FUNDING

Novo Nordisk A/S.

Lower rates of cardiovascular events and mortality associated with liraglutide use in patients treated with basal insulin: A DEVOTE subanalysis (DEVOTE 10)

AIM

To compare the associations between concomitant liraglutide use versus no liraglutide use and the risk of major adverse cardiovascular events (MACE) and all-cause mortality among patients receiving basal insulin (either insulin degludec [degludec] or insulin glargine 100 units/mL [glargine U100]) in the Trial Comparing Cardiovascular Safety of Insulin Degludec versus Insulin Glargine in Patients with Type 2 Diabetes at High Risk of Cardiovascular Events (DEVOTE).

MATERIALS AND METHODS

Patients with type 2 diabetes and high cardiovascular risk were randomized 1:1 to degludec or glargine U100. Hazard ratios for MACE/mortality were calculated using a Cox regression model adjusted for treatment and time-varying liraglutide use at any time during the trial, without interaction. Sensitivity analyses were adjusted for baseline covariates including, but not limited to, age, sex, smoking and prior cardiovascular disease.

RESULTS

At baseline, 436/7637 (5.7%) patients were treated with liraglutide; after baseline, 187/7637 (2.4%) started and 210/7637 (2.7%) stopped liraglutide. Mean liraglutide exposure from randomization was 530.2 days. Liraglutide use versus no liraglutide use was associated with significantly lower hazard rates for MACE [0.62 (0.41; 0.92)_95%CI ] and all-cause mortality [0.50 (0.29; 0.88)_95%CI ]. There was no significant difference in the rate of severe hypoglycaemia with versus without liraglutide use. Multiple sensitivity analyses yielded similar results.

CONCLUSIONS

Use of liraglutide was associated with significantly lower risk of MACE and death in patients with type 2 diabetes and high cardiovascular risk using basal insulin.

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.

International Consensus on Risk Management of Diabetic Ketoacidosis in Patients With Type 1 Diabetes Treated With Sodium-Glucose Cotransporter (SGLT) Inhibitors

Sodium-glucose cotransporter (SGLT) inhibitors are new oral antidiabetes medications shown to effectively reduce glycated hemoglobin (A1C) and glycemic variability, blood pressure, and body weight without intrinsic properties to cause hypoglycemia in people with type 1 diabetes. However, recent studies, particularly in individuals with type 1 diabetes, have demonstrated increases in the absolute risk of diabetic ketoacidosis (DKA). Some cases presented with near-normal blood glucose levels or mild hyperglycemia, complicating the recognition/diagnosis of DKA and potentially delaying treatment. Several SGLT inhibitors are currently under review by the U.S. Food and Drug Administration and European regulatory agencies as adjuncts to insulin therapy in people with type 1 diabetes. Strategies must be developed and disseminated to the medical community to mitigate the associated DKA risk. This Consensus Report reviews current data regarding SGLT inhibitor use and provides recommendations to enhance the safety of SGLT inhibitors in people with type 1 diabetes.

Association of Fenofibrate Therapy With Long-term Cardiovascular Risk in Statin-Treated Patients With Type 2 Diabetes

Importance

Patients with type 2 diabetes are at high risk of cardiovascular disease (CVD) in part owing to hypertriglyceridemia and low high-density lipoprotein cholesterol. It is unknown whether adding triglyceride-lowering treatment to statin reduces this risk.

Objective

To determine whether fenofibrate reduces CVD risk in statin-treated patients with type 2 diabetes.

Design, Setting, and Participants

Posttrial follow-up of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) Lipid Study between July 2009 and October 2014; 5 years of follow-up were completed for a total of 9.7 years at general community and academic outpatient research clinics in the United States and Canada. Of the original 5518 ACCORD Lipid Trial participants, 4644 surviving participants were selected based on the presence of type 2 diabetes and either prevalent CVD or CVD risk factors and high-density lipoprotein levels less than 50 mg/dL (<55 mg/dL for women and African American individuals).

Interventions

Passive follow-up of study participants previously treated with fenofibrate or masked placebo.

Main Outcomes and Measures

Occurrence of cardiovascular outcomes including primary composite outcome of fatal and nonfatal myocardial infarction and stroke in all participants and in prespecified subgroups.

Results

The 4644 follow-on study participants were broadly representative of the original ACCORD study population and included significant numbers of women (n = 1445; 31%), nonwhite individuals (n = 1094; 21%), and those with preexisting cardiovascular events (n = 1620; 35%). Only 4.3% of study participants continued treatment with fenofibrate following completion of ACCORD. High-density lipoprotein and triglyceride values rapidly equalized among participants originally randomized to fenofibrate or placebo. Over a median total postrandomization follow-up of 9.7 years, the hazard ratio (HR) for the primary study outcome among participants originally randomized to fenofibrate vs placebo (HR, 0.93; 95% CI, 0.83-1.05; P = .25) was comparable with that originally observed in ACCORD (HR, 0.92; 95% CI, 0.79-1,08; P = .32). Despite these overall neutral results, we continued to find evidence that fenofibrate therapy effectively reduced CVD in study participants with dyslipidemia, defined as triglyceride levels greater than 204 mg/dL and high-density lipoprotein cholesterol levels less than 34 mg/dL (HR, 0.73; 95% CI, 0.56-0.95).

Conclusions and Relevance

Extended follow-up of ACCORD-lipid trial participants confirms the original neutral effect of fenofibrate in the overall study cohort. The continued observation of heterogeneity of treatment response by baseline lipids suggests that fenofibrate therapy may reduce CVD in patients with diabetes with hypertriglyceridemia and low high-density lipoprotein cholesterol. A definitive trial of fibrate therapy in this patient population is needed to confirm these findings.

Trial Registration

clinicaltrials.gov Identifier: NCT00000620.

Glucose transporter inhibitor-conjugated insulin mitigates hypoglycemia

Insulin therapy in the setting of type 1 and advanced type 2 diabetes is complicated by increased risk of hypoglycemia. This potentially fatal complication could be mitigated by a glucose-responsive insulin analog. We report an insulin-facilitated glucose transporter (Glut) inhibitor conjugate, in which the insulin molecule is rendered glucose-responsive via conjugation to an inhibitor of Glut. The binding affinity of this insulin analog to endogenous Glut is modulated by plasma and tissue glucose levels. In hyperglycemic conditions (e.g., uncontrolled diabetes or the postprandial state), the in situ-generated insulin analog-Glut complex is driven to dissociate, freeing the insulin analog and glucose-accessible Glut to restore normoglycemia. Upon overdose, enhanced binding of insulin analog to Glut suppresses the glucose transport activity of Glut to attenuate further uptake of glucose. We demonstrate the ability of this insulin conjugate to regulate blood glucose levels within a normal range while mitigating the risk of hypoglycemia in a type 1 diabetic mouse model.

Improved Time in Range and Glycemic Variability With Sotagliflozin in Combination With Insulin in Adults With Type 1 Diabetes: A Pooled Analysis of 24-Week Continuous Glucose Monitoring Data From the inTandem Program

OBJECTIVE

To evaluate effects of the dual sodium-glucose cotransporter (SGLT) 1 and SGLT2 inhibitor sotagliflozin in combination with insulin on glucose time in range (TIR) and glucose excursions, postprandial glucose (PPG), and other glycemic metrics in adults with type 1 diabetes using masked continuous glucose monitoring (CGM).

RESEARCH DESIGN AND METHODS

Data sets from the inTandem1 (clinical trial reg. no. NCT02384941) and inTandem2 (clinical trial reg. no. NCT02421510) double-blind randomized trials evaluating sotagliflozin versus placebo in adults with type 1 diabetes treated with optimized insulin were pooled for analyses of masked CGM data from a subset of participants in each trial. The pooled cohort included patients randomized to receive placebo (n = 93), sotagliflozin 200 mg (n = 89), or sotagliflozin 400 mg (n = 96). The primary outcome was change from baseline to week 24 in glucose TIR (3.9-10.0 mmol/L [70-180 mg/dL]). Secondary end points included time below and above the target range and 2-h PPG level assessed after a standardized mixed meal.

RESULTS

Mean percentage of glucose TIR/percentage time spent at <3.9 mmol/L (<70 mg/dL) during week 24 was 51.6%/5.9%, 57.8%/5.5%, and 64.2%/5.5% with placebo, sotagliflozin 200 mg, and sotagliflozin 400 mg, respectively, which corresponded to a placebo-adjusted change from a baseline of +5.4%/-0.3% (P = 0.026; +1.3/-0.1 h/day) for sotagliflozin 200 mg and +11.7%/-0.1% (P < 0.001; +2.8/-0.02 h/day) for sotagliflozin 400 mg. Placebo-adjusted PPG reductions were 1.9 ± 0.7 mmol/L (35 ± 13 mg/dL; P = 0.004) and 2.8 ± 0.7 mmol/L (50 ± 13 mg/dL; P < 0.001) with sotagliflozin 200 and 400 mg, respectively.

CONCLUSIONS

Combined with optimized insulin in type 1 diabetes, sotagliflozin significantly increased glucose TIR without increasing time spent at <3.9 mmol/L and reduced PPG, thereby improving glycemic control.

Sodium-glucose co-transporter-2 inhibitor use and risk of lower-extremity amputation: Evolving questions, evolving answers

AIM

To examine whether sodium-glucose co-transporter-2 (SGLT2) inhibitors are associated with a higher risk of lower-extremity amputation than dipeptidyl-peptidase-4 (DPP-4) inhibitors and sulphonylureas.

METHODS

We conducted a retrospective cohort study, using the MarketScan Commercial Claims and Encounters Database (2013-2015), to compare the incidence of lower-extremity amputation (LEA) between initiators of SGLT2 inhibitors and initiators of two second-line drugs, DPP-4 inhibitors and sulphonylureas (SUs). We estimated crude incidence rates (IRs) and adjusted hazard ratios (aHR), with 95% confidence intervals (CIs), before and after propensity-score weighting. We additionally conducted sensitivity analyses using a comparator group of all non-metformin, non-SGLT2 inhibitor glucose-lowering drugs, as previous studies used this approach.

RESULTS

In a cohort of 328 150 individuals aged 18 to 64 years, the IR of LEA ranged from 1.5 to 2.4 per 1000 person-years. In as-treated analysis, the estimated hazard of LEA was increased among SGLT2 inhibitor initiators compared to DPP-4 inhibitor initiators (aHR 1.69, 95% CI 1.20-2.38), but not compared to SU initiators (aHR 1.02, 95% CI 0.67-1.55) or non-metformin, non-SGLT2 inhibitor initiators (aHR 1.02, 95% CI 0.54-1.93). Results were consistent in intention-to-treat analysis and across a number of sensitivity analyses.

CONCLUSIONS

Among commercially insured patients in the United States, our results suggest that initiation of SGLT2 inhibitors may increase the risk of LEA compared to initiation of DPP-4 inhibitors. Contrasting results when comparing SGLT2 inhibitor initiators to DPP-4 inhibitor and SU initiators highlight the importance of choosing appropriate comparator drugs when addressing comparative effectiveness and safety questions that can inform clinical decision-making.

Correction to: Management of hyperglycaemia in type 2 diabetes, 2018. A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD)

The affiliation details for Geltrude Mingrone are corrected below.

Impact of metformin use on the cardiovascular effects of dipeptidyl peptidase-4 inhibitors: An analysis of Medicare claims data from 2007 to 2015

AIMS

To examine the outcomes of dipeptidyl peptidase-4 (DPP-4) inhibitor initiation with and without concurrent metformin treatment.

MATERIALS AND METHODS

We identified Medicare enrollees initiating a DPP-4 inhibitor, a sulphonylurea or a thiazolidinedione. Using propensity-score-weighted Poisson models, we evaluated 1-year cardiovascular (CV) outcome incidence among initiators of DPP-4 inhibitors versus comparators in subgroups with and without concurrent metformin use, and assessed the interaction between initiation drug and metformin. Outcomes included mortality, non-fatal myocardial infarction (MI), stroke, and a composite outcome.

RESULTS

For the DPP-4 inhibitor (n = 13 391) versus sulphonylurea (n = 33 206) comparison, rate differences in composite outcome incidence favoured DPP-4 inhibitors: -2.0/100 person-years among metformin users (95% confidence interval [CI] -2.7 to -1.3) and - 1.0/100 person-years (95% CI -1.8 to -0.2) among metformin non-users. Similar rate difference trends among metformin users and non-users were seen for mortality (-1.5/100 person-years [95% CI -2.1 to -0.9] and -0.7/100 person-years [95% CI -1.4 to 0.0]) and non-fatal MI (-0.5/100 person-years [95% CI -0.8, -0.3] and 0.1/100 person-years [95% CI -0.2 to 0.4]). The interaction between DPP-4 inhibitor initiation and metformin was statistically significant for non-fatal MI (P = 0.008). For the DPP-4 inhibitor (n = 22 210) versus thiazolidinedione (n = 9517) comparison, rate differences in composite outcome incidence for DPP-4 inhibitor initiation were -0.6/100 person-years (95% CI -1.5 to 0.2) among metformin users and 1.0 (95% CI 0.0 to 2.0) among metformin non-users. Similar rate difference trends among metformin users and non-users were seen for mortality (-0.5/100 person-years [95% CI -1.3 to 0.1] and 0.8/100 person-years [95% CI -0.0 to 1.7]) and non-fatal MI (-0.1/100 person-years [95% CI -0.4 to 0.2] and 0.2/100 person-years [95% CI -0.1 to 0.6]). The interaction between DPP-4 inhibitor initiation and metformin was statistically significant for the composite outcome (P = 0.024) and mortality (P = 0.023).

CONCLUSION

Incidence rate differences in multiple CV outcomes appeared more favourable when DPP-4 inhibitor initiation occurred in the presence of metformin, suggesting a possible interaction between DPP-4 inhibitors and metformin.