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.

HbA1c Change and Diabetic Retinopathy During GLP-1 Receptor Agonist Cardiovascular Outcome Trials: A Meta-analysis and Meta-regression.

BACKGROUND: Long-term glycemic control reduces retinopathy risk, but transient worsening can occur with glucose control intensification. Glucagon-like peptide 1 receptor agonists (GLP-1RA) lower glucose, but the long-term impact on retinopathy is unknown. GLP-1RA cardiovascular outcome trials (CVOTs) provide long-term follow-up, allowing examination of retinopathy outcomes. PURPOSE: To examine the associations between retinopathy, HbA1c, systolic blood pressure (SBP), and weight in GLP-1RA CVOTs. DATA SOURCES: Systematic review identified six placebo-controlled GLP-1RA CVOTs reporting prespecified retinopathy outcomes. STUDY SELECTION: Published trial reports were used as the primary data sources. DATA EXTRACTION: HbA1c, SBP, and weight data throughout follow-up by treatment group were extracted. DATA SYNTHESIS: Random-effects model meta-analysis showed no association between GLP-1RA treatment and retinopathy (odds ratio [OR] 1.10; 95% CI 0.93, 1.30), with high heterogeneity between studies (I 2 = 52.2%; Q statistic P = 0.063). Univariate meta-regression showed an association between retinopathy and average HbA1c reduction during the overall follow-up (slope = 0.77, P = 0.007), but no relationship for SBP or weight. Sensitivity analyses for HbA1c showed a relationship at 3 months (P = 0.006) and 1 year (P = 0.002). A 0.1% (1.09 mmol/mol) increase in HbA1c reduction was associated with 6%, 14%, or 8% increased Ln(OR) for retinopathy at the 3-month, 1-year, and overall follow-up, respectively. LIMITATIONS: CVOTs were not powered to assess retinopathy outcomes and differed in retinopathy-related criteria and methodology. The median follow-up of 3.4 years is short compared with the onset of retinopathy. CONCLUSIONS: HbA1c reduction was significantly associated with increased retinopathy risk in meta-regression for GLP-1RA CVOTs. The magnitude of HbA1c reduction was correlated with retinopathy risk in people with diabetes and additional cardiovascular risk factors, but the long-term impact of improved glycemic control on retinopathy was unmeasured in these studies. Retinopathy status should be assessed when intensifying glucose-lowering therapy.

Clinical Outcomes by Albuminuria Status with Dulaglutide versus Insulin Glargine in Participants with Diabetes and CKD: AWARD-7 Exploratory Analysis.

Background: In the AWARD-7 trial of participants with type 2 diabetes (T2DM) and moderate-to-severe CKD, dulaglutide (DU) treatment slowed decline in eGFR compared with insulin glargine (IG). Treatment with doses of either DU or IG resulted in similar levels of glycemic control and BP. The aim of this analysis was to determine the risk of clinical event outcomes between treatment groups. Methods: Participants with T2DM and CKD categories 3-4 were randomized (1:1:1) to 0.75 or 1.5 mg DU weekly or IG daily as basal therapy, with titrated insulin lispro, for 1 year. The time to occurrence of the composite outcome of ≥40% eGFR decline, ESKD, or death due to kidney disease was compared using a Cox proportional-hazards model. Results: Patients treated with 1.5 mg DU weekly versus IG daily for 1 year had a lower risk of ≥40% eGFR decline or ESKD events in the overall study population (5% versus 11%; hazard ratio, 0.45; 95% CI, 0.20 to 0.97; P=0.04). Most events occurred in the subset of patients with macroalbuminuria, where risk of the composite outcome was substantially lower for 1.5 mg DU versus IG (7% versus 22%; hazard ratio, 0.25; 95% CI, 0.10 to 0.68; P=0.006). No deaths due to kidney disease occurred. Conclusions: Treatment with 1.5 mg DU weekly was associated with a clinically relevant risk reduction of ≥40% eGFR decline or ESKD compared with IG daily, particularly in the macroalbuminuria subgroup of participants with T2DM and moderate-to-severe CKD.

Body weight and eGFR during dulaglutide treatment in type 2 diabetes and moderate-to-severe chronic kidney disease (AWARD-7).

In patients with type 2 dibetes and moderate-to-severe chronic kidney disease, dulaglutide treatment led to body weight (BW) loss and lesser eGFR decline compared to insulin glargine. As BW may affect muscle mass, creatinine-based eGFR can be altered independently of kidney function. Cystatin C-based eGFR is not affected by muscle mass. The objective of this post-hoc analysis was to determine whether the lesser eGFR decline with dulaglutide was related to BW loss. Baseline characteristics were similar between treatments ([mean ± SD] age, 64.6 ± 8.6 years; women, 48%; BW, 89.1 ± 17.7 kg; eGFR [CKD-EPI-cystatin C] 38 ± 14 mL/min/1.73m2 ). BW decreased with dulaglutide 1.5 and 0.75 mg and increased with insulin glargine ([LSM change (SE)], -2.66 [0.47] kg and -1.71 [0.45] vs 1.57 [0.43] kg; P < 0.001). Changes in eGFR were not significant with dulaglutide 1.5 and 0.75 mg, but eGFR significantly decreased with insulin glargine (eGFR-CKD-EPI-cystatin C [LSM change (95%CI)], -0.7 [-2.5, 1.0] and -0.7 [-2.4, 1.1] vs -3.3 [-5.1, -1.6] mL/min/1.73 m2 ; P ≤ 0.037 vs glargine). Changes in BW did not correlate with changes in eGFR-CKD-EPI-cystatin C (r = -0.041; n = 471; P = 0.379) or eGFR-CKD-EPI-creatinine (r = -0.074; n = 473; P = 0.106). In conclusion, the lesser decline in eGFR observed with dulaglutide was not influenced by BW loss.

Generalizability of glucagon-like peptide-1 receptor agonist cardiovascular outcome trials to the overall type 2 diabetes population in the United States.

AIM: To examine the generalizability of results from glucagon-like peptide-1 receptor agonist (GLP-1 RA) cardiovascular outcome trials (CVOTs) in the US type 2 diabetes (T2D) population. MATERIALS AND METHODS: Patients enrolled or eligible for inclusion in four CVOTs (EXSCEL, LEADER, REWIND, and SUSTAIN-6) were examined in reference to a retrospective clinical database weighted to match the age and sex distribution of the US adult T2D population. We descriptively compared key baseline characteristics of the populations enrolled in each trial to those of the reference population and estimated the proportions of individuals in the reference population represented by those in the trials for each characteristic. We also estimated the proportions of individuals in the reference population that might have been enrolled in each trial based upon meeting the trial inclusion and exclusion (I/E) criteria. RESULTS: No trial's enrolled population perfectly matched the reference population in key characteristics. The EXSCEL population most closely matched in mean age (62.7 vs. 60.5 years) and percentage with estimated glomerular filtration rate <60 (18.6 vs. 17.3%), while REWIND most closely matched in HbA1c, sex distribution, and proportion with a prior myocardial infarction. Based on I/E criteria, 42.6% of the reference population were eligible for enrolment in REWIND, versus 15.9% in EXSCEL, 13.0% in SUSTAIN-6, and 12.9% in LEADER. CONCLUSIONS: Although none of the trials are fully representative of the general population, among the four trials examined, results from baseline REWIND were found to be more generalizable to the US adult T2D population than those of other GLP-1 RA CVOTs.

Dulaglutide versus insulin glargine in patients with type 2 diabetes and moderate-to-severe chronic kidney disease (AWARD-7): a multicentre, open-label, randomised trial.

BACKGROUND: Many antihyperglycaemic drugs, including insulin, are primarily cleared by the kidneys, restricting treatment options for patients with kidney disease. Dulaglutide is a long-acting glucagon-like peptide-1 receptor agonist that is not cleared by the kidneys, and confers a lower risk of hypoglycaemia than does insulin. We assessed the efficacy and safety of dulaglutide in patients with type 2 diabetes and moderate-to-severe chronic kidney disease. METHODS: AWARD-7 was a multicentre, open-label trial done at 99 sites in nine countries. Eligible patients were adults with type 2 diabetes and moderate-to-severe chronic kidney disease (stages 3-4), with an HbA1c of 7·5-10·5%, and who were being treated with insulin or insulin plus an oral antihyperglycaemic drug and were taking a maximum tolerated dose of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Participants were randomly assigned (1:1:1) by use of a computer-generated random sequence with an interactive response system to once-weekly injectable dulaglutide 1·5 mg, once-weekly dulaglutide 0·75 mg, or daily insulin glargine as basal therapy, all in combination with insulin lispro, for 52 weeks. Insulin glargine and lispro doses were titrated as per an adjustment algorithm; dulaglutide doses were masked to participants and investigators. The primary outcome was HbA1c at 26 weeks, with a 0·4% non-inferiority margin. Secondary outcomes included estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR). The primary analysis population was all randomly assigned patients who received at least one dose of study treatment and had at least one post-randomisation HbA1c measurement. The safety population was all patients who received at least one dose of study treatment and had any post-dose data. This study is registered with ClinicalTrials.gov, number NCT01621178. FINDINGS: Between Aug 15, 2012, and Nov 30, 2015, 577 patients were randomly assigned, 193 to dulaglutide 1·5 mg, 190 to dulaglutide 0·75 mg, and 194 to insulin glargine. The effects on HbA1c change at 26 weeks of dulaglutide 1·5 mg and 0·75 mg were non-inferior to those of insulin glargine (least squares mean [LSM] -1·2% [SE 0·1] with dulaglutide 1·5 mg [183 patients]; -1·1% [0·1] with dulaglutide 0·75 mg [180 patients]; -1·1% [0·1] with insulin glargine [186 patients]; one-sided p≤0·0001 for both dulaglutide doses vs insulin glargine). The differences in HbA1c concentration at 26 weeks between dulaglutide and insulin glargine treatments were LSM difference -0·05% (95% CI -0·26 to 0·15, p<0·0001) with dulaglutide 1·5 mg and 0·02% (-0·18 to -0·22, p=0·0001) with dulaglutide 0·75 mg. HbA1c-lowering effects persisted to 52 weeks (LSM -1·1% [SE 0·1] with dulaglutide 1·5 mg; -1·1% [0·1] with dulaglutide 0·75 mg; -1·0% [0·1] with insulin glargine). At 52 weeks, eGFR was higher with dulaglutide 1·5 mg (Chronic Kidney Disease Epidemiology Collaboration equation by cystatin C geometric LSM 34·0 mL/min per 1·73 m2 [SE 0·7]; p=0·005 vs insulin glargine) and dulaglutide 0·75 mg (33·8 mL/min per 1·73 m2 [0·7]; p=0·009 vs insulin glargine) than with insulin glargine (31·3 mL/min per 1·73 m2 [0·7]). At 52 weeks, the effects of dulaglutide 1·5 mg and 0·75 mg on UACR reduction were not significantly different from that of insulin glargine (LSM -22·5% [95% CI -35·1 to -7·5] with dulaglutide 1·5 mg; -20·1% [-33·1 to -4·6] with dulaglutide 0·75 mg; -13·0% [-27·1 to 3·9] with insulin glargine). Proportions of patients with any serious adverse events were similar across groups (20% [38 of 192] with dulaglutide 1·5 mg, 24% [45 of 190] with dulaglutide 0·75 mg, and 27% [52 of 194] with insulin glargine). Dulaglutide was associated with higher rates of nausea (20% [38 of 192] with dulaglutide 1·5 mg and 14% [27 of 190] with 0·75 mg, vs 5% [nine of 194] with insulin glargine) and diarrhoea (17% [33 of 192] with dulaglutide 1·5 mg and 16% [30 of 190] with 0·75 mg, vs 7% [14 of 194] with insulin glargine) and lower rates of symptomatic hypoglycaemia (4·4 events per patient per year with dulaglutide 1·5 mg and 4·3 with dulaglutide 0·75 mg, vs 9·6 with insulin glargine). End-stage renal disease occurred in 38 participants: eight (4%) of 192 with dulaglutide 1·5 mg, 14 (7%) of 190 with dulaglutide 0·75 mg, and 16 (8%) of 194 with insulin glargine. INTERPRETATION: In patients with type 2 diabetes and moderate-to-severe chronic kidney disease, once-weekly dulaglutide produced glycaemic control similar to that achieved with insulin glargine, with reduced decline in eGFR. Dulaglutide seems to be safe to use to achieve glycaemic control in patients with moderate-to-severe chronic kidney disease. FUNDING: Eli Lilly and Company.

Teriparatide for acceleration of fracture repair in humans: a prospective, randomized, double-blind study of 102 postmenopausal women with distal radial fractures.

Animal experiments show a dramatic improvement in skeletal repair by teriparatide. We tested the hypothesis that recombinant teriparatide, at the 20 microg dose normally used for osteoporosis treatment or higher, would accelerate fracture repair in humans. Postmenopausal women (45 to 85 years of age) who had sustained a dorsally angulated distal radial fracture in need of closed reduction but no surgery were randomly assigned to 8 weeks of once-daily injections of placebo (n = 34) or teriparatide 20 microg (n = 34) or teriparatide 40 microg (n = 34) within 10 days of fracture. Hypotheses were tested sequentially, beginning with the teriparatide 40 microg versus placebo comparison, using a gatekeeping strategy. The estimated median time from fracture to first radiographic evidence of complete cortical bridging in three of four cortices was 9.1, 7.4, and 8.8 weeks for placebo and teriparatide 20 microg and 40 microg, respectively (overall p = .015). There was no significant difference between the teriparatide 40 microg versus placebo groups (p = .523). In post hoc analyses, there was no significant difference between teriparatide 40 microg versus 20 microg (p = .053); however, the time to healing was shorter in teriparatide 20 microg than placebo (p = .006). The primary hypothesis that teriparatide 40 microg would shorten the time to cortical bridging was not supported. The shortened time to healing for teriparatide 20 microg compared with placebo still may suggest that fracture repair can be accelerated by teriparatide, but this result should be interpreted with caution and warrants further study.