Utility of adiponectin as a biomarker predictive of glycemic efficacy is demonstrated by collaborative pooling of data from clinical trials conducted by multiple sponsors

PPAR Gamma Receptor: A Novel Target to Improve Morbidity in Preterm Babies

Worldwide, three-quarters of a million babies are born extremely preterm (<28 weeks gestation) with devastating outcomes: 20% die in the newborn period, a further 35% develop bronchopulmonary dysplasia (BPD), and 10% suffer from cerebral palsy. Pioglitazone, a Peroxisome Proliferator Activated Receptor Gamma (PPARγ) agonist, may reduce the incidence of BPD and improve neurodevelopment in extreme preterm babies. Pioglitazone exerts an anti-inflammatory action mediated through Nuclear Factor-kappa B repression. PPARγ signalling is underactive in preterm babies as adiponectin remains low during the neonatal period. In newborn animal models, pioglitazone has been shown to be protective against BPD, necrotising enterocolitis, and lipopolysaccharide-induced brain injury. Single Nucleotide Polymorphisms of PPARγ are associated with inhibited preterm brain development and impaired neurodevelopment. Pioglitazone was well tolerated by the foetus in reproductive toxicology experiments. Bladder cancer, bone fractures, and macular oedema, seen rarely in adults, may be avoided with a short treatment course. The other effects of pioglitazone, including improved glycaemic control and lipid metabolism, may provide added benefit in the context of prematurity. Currently, there is no formulation of pioglitazone suitable for administration to preterm babies. A liquid formulation of pioglitazone needs to be developed before clinical trials. The potential benefits are likely to outweigh any anticipated safety concerns.

Pro12Ala polymorphism of peroxisome proliferator activated receptor gamma 2 may be associated with adverse neurodevelopment in European preterm babies

INTRODUCTION

Prematurity is the leading cause of death and disability in children under 5 years of age. Understanding the molecular mechanisms of the biological processes involved in preterm brain injury may help develop novel neuroprotective treatment strategies. A growing body of evidence suggest that peroxisome proliferator-activated receptor gamma (PPARγ) signaling is associated with inhibited brain development in preterm babies. The Ala allele of the Pro12Ala polymorphism of PPARγ2 decreases receptor binding affinity and consequently induces a reduction of PPARγ signaling.

METHODS

In this study, we carried out a preliminary analysis of existing datasets to test the hypothesis that reduced transactivation capacity of PPARγ in the presence of the Ala variant of PPARγ2 may be associated with adverse neurodevelopment in preterm babies. The association between PPAR-γ2 Pro12Ala polymorphism and neurodevelopment at 18-24 months of age was assessed in two groups of European infants, 155 born before 33 weeks' gestation and 180 born later than 36 weeks' gestation using a linear regression model. The Bayley Scales of Infant and Toddler Development-3rd edition was administered to assess neurodevelopment at 18-24 months of age.

RESULTS

We observed the Ala allele of the Pro12Ala polymorphism in 25% preterm infants and 20% term infants. The Ala allele of PPARγ2 was significantly associated with adverse cognitive (p = .019), language (p = .03), and motor development (p = 0.036) at 18-24 months of age after taking into consideration the duration of ventilation, gender, and index of multiple deprivation scores, but without correction for potential shared ancestry. There was no association between the PPAR-γ2 Pro12Ala polymorphism and neurodevelopment in term infants.

CONCLUSIONS

These preliminary data suggest that PPARγ signaling in the presence of the Ala variant of PPARγ2 may be associated with adverse neurodevelopment in preterm infants suggesting that further studies are warranted.

Effect of fish oil on circulating asymmetric dimethylarginine and adiponectin in overweight or obese patients with atrial fibrillation

Obesity and adipose-derived peptides might be involved in the pathogenesis of atrial fibrillation (AF). Adiponectin plays a major role in the modulation of several metabolic pathways, and asymmetric dimethylarginine (ADMA) has been suggested to be predictive of AF and associated adverse events. The aim of this study was to investigate the effect of fish oil supplementation on circulating adiponectin and ADMA in overweight or obese patients with persistent AF. In this randomized, double-blind, placebo-controlled trial, 80 overweight or obese (body mass index (BMI) ≥ 25 kg/m2) patients with persistent AF were randomly assigned to two groups to receive either 2 g/day fish oil or placebo, for 8 weeks. Serum levels of adiponectin and ADMA, and anthropometric indexes were measured. This study showed that serum adiponectin concentrations increased significantly following fish oil supplementation compared with the placebo group (13.15 ± 7.33 vs. 11.88 ± 6.94 µg/ml; p = .026). A significant reduction was also observed in serum ADMA levels in the fish oil compared with the placebo group following the intervention (0.6 ± 0.13 vs. 0.72 ± 0.15 µmol/L; p = .001). The changes in serum adiponectin and ADMA concentrations remained significant after adjustments for baseline values, age, sex, and changes of BMI and waist circumference (p = .011 and p = .001, respectively). In conclusion,  8 weeks supplementation with fish oil increased serum adiponectin and decreased ADMA concentrations in overweight or obese patients with persistent AF. As adiponectin and ADMA are suggested to be involved in many pathways associated with AF, the current findings might be promising in the clinical management of this disease, an issue that needs further investigations.

Predictors of response to insulin therapy in youth with poorly-controlled type 2 diabetes in the TODAY trial

OBJECTIVE

To understand the factors associated with glycemic control after starting insulin in youth with type 2 diabetes following glycemic failure (persistent HbA1c ≥8%) with metformin alone, metformin + rosiglitazone or metformin + lifestyle in the TODAY study.

METHODS

Change in HbA1c after add-on insulin therapy and the factors predictive of glycemic response were evaluated. At 1-year postinsulin initiation, 253 youth had a mean of 3.9 ± 1.0 visits since the time of insulin initiation. Participants were divided into three groups according to glycemic control: consistent decrease in HbA1c by ≥0.5%, change <0.5%, or consistent increase in HbA1c ≥0.5%, at 75% or more of the visits.

RESULTS

Within 1-year postinsulin initiation, 33.2% of participants had a consistent HbA1c decrease of ≥0.5%, 46.2% changed HbA1c <0.5%, and 20.6% had an increase ≥0.5%. At randomization into TODAY and at time of insulin initiation, the three glycemia groups were similar in age, sex, race-ethnicity, pubertal stage, BMI z-score, diabetes duration, and insulin secretion indices. Consistent HbA1c improvement was associated with higher insulin sensitivity (1/fasting insulin) at randomization and at time of failure, higher adiponectin at randomization, and was not associated with indices of β-cell function.

CONCLUSIONS

Response to add-on insulin was highly variable among youth in TODAY. Greater insulin sensitivity and higher adiponectin concentrations at randomization were associated with improved glycemic control after initiation of insulin. Due to limited information on adherence to insulin injections, the roles of adherence to the prescribed insulin regimen or psychosocial factors are unknown.

Treatment with high dose salicylates improves cardiometabolic parameters: Meta-analysis of randomized controlled trials

INTRODUCTION

There is conflicting evidence regarding the efficacy of high dose salicylates in improving cardiometabolic risk in healthy and type 2 diabetes patients. We aimed to determine whether treatment with salicylates at an anti-inflammatory dose (≥1g daily) would improve cardiometabolic risk in healthy individuals and type 2 diabetes patients, compared to placebo.

METHODS

Medline, Medline-in-process, Embase, and all EBM databases were searched for studies published up to December 2016. Twenty-eight articles from 24 studies comprising 1591 participants were included. Two reviewers independently assessed the risk of bias and extracted data from included studies. Meta-analyses using random-effects model were used to analyze the data.

RESULTS

High dose salicylates (≥3g/d) decreased fasting glucose (MD -0.4mmol/l, 95% CI -0.54, -0.27) and glucose area under the curve (MD -0.41mmol/l, 95% CI -0.81, -0.01). Salicylates (≥3g/d) also increased fasting insulin (MD 2.4 μU/ml, 95% CI 0.3, 4.4), 2-h insulin (MD 25.4 μU/ml, 95% CI 8.2, 42.6), insulin secretion (MD 79.2, 95% CI 35, 123) but decreased fasting C-peptide (MD -0.11nmol/l, 95% CI -0.2, -0.04), insulin clearance (MD -0.26l/min, 95% CI -0.36, -0.16) and triglycerides (MD -0.36mmol/l, 95% CI -0.51, -0.21) and increased total adiponectin (MD 1.97μg/ml, 95% CI 0.99, 2.95). A lower salicylate dose (1-2.9g) did not change any cardiometabolic parameters (p>0.1). No significant difference was observed between those receiving salicylates and placebo following withdrawal due to adverse events.

CONCLUSIONS

High dose salicylates appear to improve cardiometabolic risk factors in healthy individuals and type 2 diabetes patients.

PROSPERO REGISTRATION NUMBER

CRD42015029826.

Adiponectin, Insulin Sensitivity, β-Cell Function, and Racial/Ethnic Disparity in Treatment Failure Rates in TODAY

OBJECTIVE

The Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study demonstrated that glycemic failure rates in the three treatments combined-metformin plus rosiglitazone, metformin alone, and metformin plus lifestyle-were higher in non-Hispanic blacks (NHB; 52.8%) versus non-Hispanic whites (NHW; 36.6%) and Hispanics (H; 45.0%). Moreover, metformin alone was less effective in NHB versus NHW versus H youth. This study describes treatment-associated changes in adiponectin, insulin sensitivity, and β-cell function over time among the three racial/ethnic groups to understand potential mechanism(s) responsible for this racial/ethnic disparity.

RESEARCH DESIGN AND METHODS

TODAY participants underwent periodic oral glucose tolerance tests to determine insulin sensitivity, C-peptide index, and oral disposition index (oDI), with measurements of total and high-molecular-weight adiponectin (HMWA).

RESULTS

At baseline NHB had significantly lower HMWA than NHW and H and exhibited a significantly smaller increase (17.3% vs. 33.7% vs. 29.9%, respectively) during the first 6 months overall. Increases in HMWA were associated with reductions in glycemic failure in the three racial/ethnic groups combined (hazard ratio 0.61, P < 0.0001) and in each race/ethnicity separately. Over time, HMWA was significantly lower in those who failed versus did not fail treatment, irrespective of race/ethnicity. There were no differences in treatment-associated temporal changes in insulin sensitivity, C-peptide index, and oDI among the three racial/ethnic groups.

CONCLUSIONS

HMWA is a reliable biomarker of treatment response in youth with type 2 diabetes. The diminutive treatment-associated increase in HMWA in NHB (∼50% lower) compared with NHW and H may explain the observed racial/ethnic disparity with higher therapeutic failure rates in NHB in TODAY.

Repurposing historical control clinical trial data to provide safety context

Billions of dollars spent, millions of subject-hours of clinical trial experience and an abundance of archived study-level data, yet why are historical data underutilized? We propose that historical data can be aggregated to provide safety, background incidence rate and context to improve the evaluation of new medicinal products. Here, we describe the development and application of the eControls database, which is derived from the control arms of studies of licensed products, and discuss the challenges and potential solutions to the proper application of historical data to help interpret product safety.

Clinical use of adiponectin as a marker of metabolic dysregulation

Adiponectin concentrations exhibit strong cross-sectional relationships with obesity, inflammation, and diabetes. Adiponectin concentrations have been extensively evaluated as epidemiologic markers of diabetes and cardiovascular disease risk. In the present review we will provide an overview of these epidemiologic relationships as the backdrop for an evaluation of the clinical applications of adiponectin measurements. These include using adiponectin as an indicator of need for preventive or therapeutic intervention, as a predictor of response to therapy, and as a marker of therapeutic effectiveness. These efforts are laying the groundwork for the transition of adiponectin measurements from the laboratory to the clinic.

Optimal thresholds by maximizing or minimizing various metrics via ROC-type analysis

RATIONALE AND OBJECTIVES

Based on imaging features, the optimal thresholds are typically determined as cutoff points to dichotomize the corresponding measurement scales.

MATERIALS AND METHODS

Five metrics (ie, the Youden index, Euclidian distance, percent of correct diagnosis, kappa statistic, and mutual information) are individually maximized or minimized to derive the corresponding optimal threshold. These optimal thresholds are estimated under the parametric binormal assumption. Monte Carlo simulation studies are conducted to compare the performances of these different methods. A published radiological example on the choice of treatment outcomes following ureteral stones is used to illustrate and compare the estimated thresholds both empirically and parametrically.

RESULTS

The optimal threshold can be a "moving target" because it would depend on modeling assumptions, metrics, and variability in the data. Even with large samples, disease prevalence has an impact on the robustness of the metrics.

CONCLUSIONS

It is recommended that researchers compare different optimal cutoff points using several metrics and select one that is most clinically relevant. The ultimate goal is to maximize diagnostic performances that are clinically meaningful to achieve improved global health.

Creation and implementation of a historical controls database from randomized clinical trials

BACKGROUND

Ethical concerns about randomly assigning patients to suboptimal or placebo arms and the paucity of willing participants for randomization into control and experimental groups have renewed focus on the use of historical controls in clinical trials. Although databases of historical controls have been advocated, no published reports have described the technical and informatics issues involved in their creation.

OBJECTIVE

To create a historical controls database by leveraging internal clinical trial data at Pfizer, focusing on patients who received only placebo in randomized controlled trials.

METHODS

We transformed disparate clinical data sources by indexing, developing, and integrating clinical data within internal databases and archives. We focused primarily on trials mapped into a consistent standard and trials in the pain therapeutic area as a pilot.

RESULTS

Of the more than 20,000 internal Pfizer clinical trials, 2404 completed placebo controlled studies with a parallel design were identified. Due to challenges with informed consent and data standards used in older clinical trials, studies completed before 2000 were excluded, yielding 1134 studies from which placebo subjects and associated clinical data were extracted.

CONCLUSIONS

It is technically feasible to pool portions of placebo populations through a stratification and segmentation approach for a historical placebo group database. A sufficiently large placebo controls database would enable previous distribution calculations on representative populations to supplement, not eliminate, the placebo arm of future clinical trials. Creation of an industry-wide placebo controls database, utilizing a universal standard, beyond the borders of Pfizer would add significant efficiencies to the clinical trial and drug development process.

Factors determining the risk of the metabolic syndrome: is there a central role for adiponectin?

BACKGROUND AND OBJECTIVES

The pathogenesis of the metabolic syndrome (MetS) is not well understood. This review is based on the hypothesis that both traditional and emerging risk factors act through adiponectin.

SUBJECTS AND METHODS

We conducted a search of the literature using prominent electronic databases and search terms that included in combination: adiponectin, diet, dietary patterns, exercise, metabolic rate, MetS and testosterone. Articles were restricted to studies conducted on adult humans, reported in English and within the time period 2000-2012.

RESULTS AND CONCLUSIONS

Both traditional and emerging risk factors associated with the MetS show some evidence of exerting their influence through adiponectin. High-quality randomized controlled trials that alter adiponectin levels are required to further corroborate this hypothesis.

The potential role of leptin and adiponectin in obesity: a comparative review

Leptin and adiponectin are adipokines produced by the white adipose tissue. The adipokines have been shown to be valuable quantitative markers of adiposity in dogs. Leptin positively correlates with body condition score (BCS) in dogs, regardless of age, sex and breed, and is influenced by feeding state, pharmacological treatment and thyroid gland activity. Conversely, adiponectin negatively correlates with body fat mass and is therefore more abundant in lean animals. The implication of leptin and adiponectin in the pathogenesis of metabolic syndrome is well established in humans, but currently lacking in dogs. Additional studies are necessary to demonstrate their potential usefulness for monitoring the progression of obesity-related diseases and response to treatment. To date, measurement of canine leptin and adiponectin has been used in experimental studies only, whereas bodyweight and BCS are considered the first-approach parameters for the routine assessment of body fat content in obese dogs.

Translational biomarkers: from preclinical to clinical a report of 2009 AAPS/ACCP Biomarker Workshop

There have been some successes in qualifying biomarkers and applying them to drug development and clinical treatment of various diseases. A recent success is illustrated by a collaborative effort among the US Food and Drug Administration, the European Medicines Agency, and the pharmaceutical industry to provide a set of seven preclinical kidney toxicity biomarkers for drug development. Other successes include, but are not limited to, clinical biomarkers for cancer treatment and clinical management of heart transplant patients. The value of fully qualified surrogate endpoints in facilitating successful drug development is undisputed, especially for diseases in which the traditional clinical outcome can only be assessed in large, multi-year trials. Emerging biomarkers, including chemical genomic or imaging biomarkers, and measurement of circulating tumor cells hold great promise for early diagnosis of disease and as prognostic tests for managing treatment of chronic diseases such as osteoarthritis, Alzheimer disease, cardiovascular disease, and cancer. To advance the success of treating and managing these diseases, efforts are needed to establish the temporal relationship between changes in inflammatory or imaging biomarkers with the progression of the chronic disease, and in the case of cancer, between the extent of circulating cancer cells and tumor progression or remission.

Pharmacodynamic effects of rosiglitazone in nondiabetic patients with metabolic syndrome

STUDY OBJECTIVES

To determine the effects of the thiazolidinedione rosiglitazone on the adipocyte-derived cytokines adiponectin (an antiinflammatory and insulin-sensitizing cytokine; low levels have been associated with metabolic syndrome) and resistin (an inflammation mediator; high levels have been associated with metabolic syndrome) in nondiabetic patients with metabolic syndrome, and to characterize the effects of rosiglitazone on other components of the metabolic syndrome phenotype in this population.

DESIGN

Prospective, randomized, double-blind, placebo-controlled study.

SETTING

Outpatient general clinical research center.

PATIENTS

Thirty-two nondiabetic men and women with a clinical diagnosis of metabolic syndrome (as defined in the American Heart Association-National Heart, Lung, and Blood Institute scientific statement).

INTERVENTION

Patients were randomly assigned to receive either oral rosiglitazone 4 mg/day or matching placebo for 12 weeks.

MEASUREMENTS AND MAIN RESULTS

The primary end point was change in serum adiponectin concentrations from baseline to week 12. Secondary end points were changes in serum resistin concentrations, insulin resistance, fasting glucose level, fasting insulin level, body weight, lipid levels, systolic and diastolic blood pressure, and waist circumference from baseline to week 12. Also, changes from baseline in adiponectin and resistin concentrations and insulin resistance were assessed over time at weeks 2, 4, 8, and 12. Rosiglitazone was associated with a significant increase in serum adiponectin concentration after 12 weeks compared with placebo (45.8% vs 2.6%, p=0.002). The increase in adiponectin concentration occurred quickly, with a significant difference observed after 2 weeks of therapy. Compared with placebo, rosiglitazone was not associated with significant 12-week changes in serum resistin concentrations, insulin resistance, fasting glucose level, fasting insulin level, body weight, lipid levels, systolic or diastolic blood pressure, or waist circumference.

CONCLUSION

Rosiglitazone had beneficial effects on adiponectin concentrations without significantly affecting other components of the metabolic syndrome phenotype. Additional studies that further elucidate the time course of thiazolidinedione pharmacodynamic effects, along with their effects on cardiovascular end points, are warranted in nondiabetic patients with metabolic syndrome.

The effects of salsalate on glycemic control in patients with type 2 diabetes: a randomized trial

BACKGROUND

Salsalate, a nonacetylated prodrug of salicylate, has been shown to decrease blood glucose concentration in small studies.

OBJECTIVE

To compare the efficacy and safety of salsalate at different doses in patients with type 2 diabetes.

DESIGN

Parallel randomized trial with computer-generated randomization and centralized allocation. Patients and investigators, including those assessing outcomes and performing analyses, were masked to group assignment. (ClinicalTrials.gov registration number: NCT00392678)

SETTING

3 private practices and 14 universities in the United States.

PATIENTS

Persons aged 18 to 75 years with fasting plasma glucose concentrations of 12.5 mmol/L or less (< or = 225 mg/dL) and hemoglobin A1c (HbA1c) levels of 7.0% to 9.5% treated by diet, exercise, and oral medication at stable doses for at least 8 weeks.

INTERVENTION

After a 4-week, single-masked run-in period, patients were randomly assigned to receive placebo or salsalate in dosages of 3.0, 3.5, or 4.0 g/d for 14 weeks (27 patients each) in addition to their current therapy.

MEASUREMENTS

Change in HbA1c was the primary outcome. Adverse effects and changes in measures of coronary risk and renal function were secondary outcomes.

RESULTS

Higher proportions of patients in the 3 salsalate treatment groups experienced decreases in HbA1c levels of 0.5% or more from baseline (P = 0.009). Mean HbA1c changes were -0.36% (P = 0.02) at 3.0 g/d, -0.34% (P = 0.02) at 3.5 g/d, and -0.49% (P = 0.001) at 4.0 g/d compared with placebo. Other markers of glycemic control also improved in the 3 salsalate groups, as did circulating triglyceride and adiponectin concentrations. Mild hypoglycemia was more common with salsalate; documented events occurred only in patients taking sulfonylureas. Urine albumin concentrations increased in all salsalate groups compared with placebo. The drug was otherwise well tolerated.

LIMITATION

The number of patients studied and the trial duration were insufficient to warrant recommending the use of salsalate for type 2 diabetes at this time.

CONCLUSION

Salsalate lowers HbA1c levels and improves other markers of glycemic control in patients with type 2 diabetes and may therefore provide a new avenue for treatment. Renal and cardiac safety of the drug require further evaluation.

PRIMARY FUNDING SOURCE

National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.

The effects of salsalate on glycemic control in patients with type 2 diabetes: a randomized trial

BACKGROUND

Salsalate, a nonacetylated prodrug of salicylate, has been shown to decrease blood glucose concentration in small studies.

OBJECTIVE

To compare the efficacy and safety of salsalate at different doses in patients with type 2 diabetes.

DESIGN

Parallel randomized trial with computer-generated randomization and centralized allocation. Patients and investigators, including those assessing outcomes and performing analyses, were masked to group assignment. (ClinicalTrials.gov registration number: NCT00392678)

SETTING

3 private practices and 14 universities in the United States.

PATIENTS

Persons aged 18 to 75 years with fasting plasma glucose concentrations of 12.5 mmol/L or less (< or = 225 mg/dL) and hemoglobin A1c (HbA1c) levels of 7.0% to 9.5% treated by diet, exercise, and oral medication at stable doses for at least 8 weeks.

INTERVENTION

After a 4-week, single-masked run-in period, patients were randomly assigned to receive placebo or salsalate in dosages of 3.0, 3.5, or 4.0 g/d for 14 weeks (27 patients each) in addition to their current therapy.

MEASUREMENTS

Change in HbA1c was the primary outcome. Adverse effects and changes in measures of coronary risk and renal function were secondary outcomes.

RESULTS

Higher proportions of patients in the 3 salsalate treatment groups experienced decreases in HbA1c levels of 0.5% or more from baseline (P = 0.009). Mean HbA1c changes were -0.36% (P = 0.02) at 3.0 g/d, -0.34% (P = 0.02) at 3.5 g/d, and -0.49% (P = 0.001) at 4.0 g/d compared with placebo. Other markers of glycemic control also improved in the 3 salsalate groups, as did circulating triglyceride and adiponectin concentrations. Mild hypoglycemia was more common with salsalate; documented events occurred only in patients taking sulfonylureas. Urine albumin concentrations increased in all salsalate groups compared with placebo. The drug was otherwise well tolerated.

LIMITATION

The number of patients studied and the trial duration were insufficient to warrant recommending the use of salsalate for type 2 diabetes at this time.

CONCLUSION

Salsalate lowers HbA1c levels and improves other markers of glycemic control in patients with type 2 diabetes and may therefore provide a new avenue for treatment. Renal and cardiac safety of the drug require further evaluation.

PRIMARY FUNDING SOURCE

National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.

Biomarker qualification via public-private partnerships

Biomarkers linked to patient outcomes (safety and efficacy) have an increasingly important role in drug development. Consequently, validation and qualification of such biomarkers are essential, often requiring large data sets from well-controlled randomized clinical trials. In the December 2009 issue of Clinical Pharmacology & Therapeutics, investigators utilizing data from four pharmaceutical companies and working under the auspices of the Biomarkers Consortium described the utility of adiponectin as an early predictor of glycemic control in diabetic patients taking peroxisome proliferator-activated receptor (PPAR) agonists. This work illustrates the advantages of large public-private partnerships for biomarker qualification.