Targeting the kidney and glucose excretion with dapagliflozin: preclinical and clinical evidence for SGLT2 inhibition as a new option for treatment of type 2 diabetes mellitus

Dapagliflozin improves podocytes injury in diabetic nephropathy via regulating cholesterol balance through KLF5 targeting the ABCA1 signalling pathway

Diabetic nephropathy (DN), one of the more prevalent microvascular complications in patients diagnosed with diabetes mellitus, is attributed as the main cause of end-stage renal disease (ESRD). Lipotoxicity in podocytes caused by hyperglycemia has been recognised as a significant pathology change, resulting in the deterioration of the glomerular filtration barrier. Research has demonstrated how dapagliflozin, a kind of SGLT2i, exhibits a multifaceted and powerful protective effect in DN, entirely independent of the hypoglycemic effect, with the specific mechanism verified. In this present study, we found that dapagliflozin has the potential to alleviate apoptosis and restore cytoskeleton triggered by high glucose (HG) in vivo and in vitro. We also discovered that dapagliflozin could mitigate podocyte cholesterol accumulation by restoring the expression of ABCA1, which is the key pathway for cholesterol outflows. This research also mechanistically demonstrates that the protective effect of dapagliflozin can be mediated by KLF-5, which is the upstream transcription factor of ABCA1. Taken together, our data suggest that dapagliflozin offers significant potential in alleviating podocyte injury and cholesterol accumulation triggered by high glucose. In terms of the mechanism, we herein reveal that dapagliflozin could accelerate cholesterol efflux by restoring the expression of ABCA1, which is directly regulated by KLF-5.

Gastroprotective effect of dapagliflozin in ethanol-induced gastric lesions in rats: Crosstalk between HMGB1/RAGE/PTX3 and TLR4/MyD88/VEGF/PDGF signaling pathways

Alcohol abuse may lead to the development of gastric mucosal lesions. Dapagliflozin (DAPA), a sodium-glucose cotransporter-2 inhibitor, is clinically used to treat type 2 diabetes mellitus. However, studies showed protective effect of DAPA under various experimental conditions by alleviating oxidative stress and inflammation. The effect of DAPA on experimental gastric ulcer has not been studied yet. Therefore, we attempted to investigate DAPA's protective effect against ethanol (EtOH)-induced gastric lesions. Fifty-six (8-week-old) male Wistar rats were divided into seven groups. DAPA (1, 5, and 10 mg/kg/day; p.o.) was given for seven days, plus a single dose of absolute EtOH (5 ml/kg) on day 8. According to hematoxylin and eosin, and Alcian blue staining of gastric tissue sections, titratable acidity, and macroscopic assessments, DAPA high dose (10 mg/kg) was the most protective, with lesser ulcerations, and higher mucin, relative to the lower two doses and the standard treatment omeprazole (OME). In rats pre-treated with DAPA high dose, colorimetric and ELISA analyses revealed significantly decreased oxidative stress, pro-inflammatory, and apoptosis indices and increased levels of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). Western blot analysis revealed reduced pentraxin-3 (PTX3), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE), toll-like receptor 4 (TLR4), and myeloid differentiation factor 88 (MyD88) expression. These results were comparable in DAPA (10 mg/kg) and OME pre-treated groups. Overall, DAPA exerted a dose-dependent protective effect against EtOH-induced gastric injury. Gastroprotective effects of DAPA (10 mg/kg) may be associated with influencing HMGB1/RAGE/PTX3 and TLR4/MyD88/VEGF/PDGF pathways.

Dapagliflozin Prevents Kidney Glycogen Accumulation and Improves Renal Proximal Tubule Cell Functions in a Mouse Model of Glycogen Storage Disease Type 1b

BACKGROUND

Mutations in SLC37A4, which encodes the intracellular glucose transporter G6PT, cause the rare glycogen storage disease type 1b (GSD1b). A long-term consequence of GSD1b is kidney failure, which requires KRT. The main protein markers of proximal tubule function, including NaPi2A, NHE3, SGLT2, GLUT2, and AQP1, are downregulated as part of the disease phenotype.

METHODS

We utilized an inducible mouse model of GSD1b, TM-G6PT-/-, to show that glycogen accumulation plays a crucial role in altering proximal tubule morphology and function. To limit glucose entry into proximal tubule cells and thus to prevent glycogen accumulation, we administered an SGLT2-inhibitor, dapagliflozin, to TM-G6PT-/- mice.

RESULTS

In proximal tubule cells, G6PT suppression stimulates the upregulation and activity of hexokinase-I, which increases availability of the reabsorbed glucose for intracellular metabolism. Dapagliflozin prevented glycogen accumulation and improved kidney morphology by promoting a metabolic switch from glycogen synthesis toward lysis and by restoring expression levels of the main proximal tubule functional markers.

CONCLUSION

We provide proof of concept for the efficacy of dapagliflozin in preserving kidney function in GSD1b mice. Our findings could represent the basis for repurposing this drug to treat patients with GSD1b.

The Effects of Star Fruit (Averrhoa carambola Linn.) Extract on Body Mass Index, Fasting Blood Glucose, and Triglyceride Levels in Male Rats with Obesity and Type 2 Diabetes Mellitus

BACKGROUND: Obesity is the main risk factor of diabetes by which induces insulin resistance. Epicatechin gallate can virtually interact with sodium-glucose co-transporter 2 as same as dapagliflozin and is found in green tea and star fruits. AIM: This study aimed to investigate the effects of methanol extract of star fruit (MES) on body weight (BW), body mass index (BMI), fasting blood glucose (FBG), and triglyceride levels in male rats with obesity and type 2 diabetes mellitus (T2DM). METHODS: Twenty-four male Sprague-Dawley rats were randomly assigned to normal and high-fat diet (HFD) groups. Obesity was induced with a HFD diet for 5 weeks and followed by induction of T2DM with 230 mg/kg BW nicotinamide and 65 mg/kg BW streptozotocin injections. Twenty-one obesity and T2DM rats were randomly assigned to negative control (n = 3) and the remaining rats in the MES1-3 groups, which were given 250, 500, and 1000 mg/kg BW/day MES. Data of BW, BMI, FBG, and triglyceride levels were collected at day 1, 14, and 28 interventions. Data were statistically analyzed using parametric and non-parametric tests with p < 0.05 considered significant. RESULTS: The MES3 group (282.56 ± 10.75 g) had significantly lower mean BW than the MES2 group (331.33 ± 13.17 g, p = 0.035). The duration of MES administration significantly decreased BW (p = 0.009) and BMI (p = 0.034) compared with the negative control. The mean triglyceride levels in MES1 (93.72 ± 53.69 mg/dl, p = 0.020), MES2 (71.98 ± 35.72 mg/dl, p = 0.025), and MES3 (56.68 ± 16.37 mg/dl, p = 0.020) groups significantly lower than the control group (1042.13 ± 681.74 mg/dl) on day 14. The mean FBG levels in MES1 (437.85 ± 33.04 mg/dl) and MES2 (353 ± 33.04 mg/dl) groups were also lower than the control group (470.97 ± 33.04 mg/dl). CONCLUSION: Administrations of 250, 500, and 1000 mg/kg BW/day MES decrease BW, BMI, and triglyceride level but increase FBG level in male rats with obesity and T2DM for 14 and 28 days.

Sex-Specific Computational Models of Kidney Function in Patients With Diabetes

The kidney plays an essential role in homeostasis, accomplished through the regulation of pH, electrolytes and fluids, by the building blocks of the kidney, the nephrons. One of the important markers of the proper functioning of a kidney is the glomerular filtration rate. Diabetes is characterized by an enlargement of the glomerular and tubular size of the kidney, affecting the afferent and efferent arteriole resistance and hemodynamics, ultimately leading to chronic kidney disease. We postulate that the diabetes-induced changes in kidney may exhibit significant sex differences as the distribution of renal transporters along the nephron may be markedly different between women and men, as recently shown in rodents. The goals of this study are to (i) analyze how kidney function is altered in male and female patients with diabetes, and (ii) assess the renal effects, in women and men, of an anti-hyperglycemic therapy that inhibits the sodium-glucose cotransporter 2 (SGLT2) in the proximal convoluted tubules. To accomplish these goals, we have developed computational models of kidney function, separate for male and female patients with diabetes. The simulation results indicate that diabetes enhances Na⁺ transport, especially along the proximal tubules and thick ascending limbs, to similar extents in male and female patients, which can be explained by the diabetes-induced increase in glomerular filtration rate. Additionally, we conducted simulations to study the effects of diabetes and SGLT2 inhibition on solute and water transport along the nephrons. Model simulations also suggest that SGLT2 inhibition raises luminal [Cl^–] at the macula densa, twice as much in males as in females, and could indicate activation of the tubuloglomerular feedback signal. By inducing osmotic diuresis in the proximal tubules, SGLT2 inhibition reduces paracellular transport, eventually leading to diuresis and natriuresis. Those effects on urinary excretion are blunted in women, in part due to their higher distal transport capacity.

Cost-Utility Analysis of Dapagliflozin Versus Saxagliptin Treatment as Monotherapy or Combination Therapy as Add-on to Metformin for Treating Type 2 Diabetes Mellitus

OBJECTIVE

To assess the long-term cost effectiveness of dapagliflozin (DAPA) and saxagliptin (SAXA) separately or together in patients with type 2 diabetes mellitus (T2DM) inadequately controlled by metformin (MET).

METHODS

Five head-to-head randomised controlled trials of the efficacy of DAPA and SAXA in type 2 diabetes mellitus (T2DM) patients were found by searching PubMed, Embase and Cochrane from inception to October 2019. The lifetime disease progression and long-term effectiveness of therapy in patients were projected by the United Kingdom Prospective Diabetes Study Outcome Model 2 (UKPDS OM2) in three T2DM therapeutic groups: DAPA + SAXA, DAPA and SAXA. Each group used DAPA and/or SAXA as an add-on therapy to MET. The study took the perspective of Chinese healthcare service providers. Univariate, scenario and probabilistic sensitivity analyses were performed.

RESULTS

The quality-adjusted life-years (QALYs) value of the DAPA + SAXA, SAXA and DAPA groups were 11.28, 11.26 and 11.45 years, respectively. The total costs were US$27,954.84, US$23,254.46 and US$25,608.49, respectively. DAPA was dominant over DAPA + SAXA. The DAPA + SAXA group presented an estimated QALY gain of 0.02 and a total cost increase of US$4700.39 over the SAXA group, with an incremental cost of US$217,530.10 per QALY. Compared with the SAXA group, the DAPA group had a QALY gain of 0.19 years and a total cost increase of US$2354.04, for an incremental cost of US$12,191.97 per QALY. The pharmacoeconomic results were robust to univariate, scenario and probabilistic sensitivity analyses.

CONCLUSIONS

Compared with DAPA + SAXA or SAXA, DAPA appears to be a cost-effective therapy as add-on to MET for Chinese patients whose T2DM is insufficiently controlled by MET.

Glucose transporters in pancreatic islets

The fine-tuning of glucose uptake mechanisms is rendered by various glucose transporters with distinct transport characteristics. In the pancreatic islet, facilitative diffusion glucose transporters (GLUTs), and sodium-glucose cotransporters (SGLTs) contribute to glucose uptake and represent important components in the glucose-stimulated hormone release from endocrine cells, therefore playing a crucial role in blood glucose homeostasis. This review summarizes the current knowledge about cell type-specific expression profiles as well as proven and putative functions of distinct GLUT and SGLT family members in the human and rodent pancreatic islet and further discusses their possible involvement in onset and progression of diabetes mellitus. In context of GLUTs, we focus on GLUT2, characterizing the main glucose transporter in insulin-secreting β-cells in rodents. In addition, we discuss recent data proposing that other GLUT family members, namely GLUT1 and GLUT3, render this task in humans. Finally, we summarize latest information about SGLT1 and SGLT2 as representatives of the SGLT family that have been reported to be expressed predominantly in the α-cell population with a suggested functional role in the regulation of glucagon release.

Probing the characteristics and biofunctional effects of disease-affected cells and drug response via machine learning applications

Drug-induced transformations in disease characteristics at the cellular and molecular level offers the opportunity to predict and evaluate the efficacy of pharmaceutical ingredients whilst enabling the optimal design of new and improved drugs with enhanced pharmacokinetics and pharmacodynamics. Machine learning is a promising in-silico tool used to simulate cells with specific disease properties and to determine their response toward drug uptake. Differences in the properties of normal and infected cells, including biophysical, biochemical and physiological characteristics, plays a key role in developing fundamental cellular probing platforms for machine learning applications. Cellular features can be extracted periodically from both the drug treated, infected, and normal cells via image segmentations in order to probe dynamic differences in cell behavior. Cellular segmentation can be evaluated to reflect the levels of drug effect on a distinct cell or group of cells via probability scoring. This article provides an account for the use of machine learning methods to probe differences in the biophysical, biochemical and physiological characteristics of infected cells in response to pharmacokinetics uptake of drug ingredients for application in cancer, diabetes and neurodegenerative disease therapies.

Differential pharmacology and clinical utility of dapagliflozin in type 2 diabetes

Dapagliflozin belongs in the family of sodium-glucose cotransporter 2 (SGLT2) inhibitors and acts by reducing glucose reabsorption in the proximal tubule. The aim of this review is to present the differential pharmacology and clinical utility of dapagliflozin. Dapagliflozin is orally administered, has a long half-life of 12.9 hours and (similar to empagliflozin) is a much weaker SGLT1 inhibitor compared with canagliflozin. Dapagliflozin significantly decreases glycated hemoglobin and fasting glucose levels in patients with type 2 diabetes mellitus (T2DM). The drug improves body weight, blood pressure, uric acid, triglycerides and high-density lipoprotein cholesterol. In the DECLARE-TIMI 58 trial, a large trial of 17,160 T2DM patients with established cardiovascular disease (CVD) or without established CVD but with multiple risk factors, dapagliflozin compared with placebo resulted in a significantly lower rate of the composite outcome of CVD death or hospitalization for heart failure (HHF); this effect was mainly due to a lower rate of HHF in the dapagliflozin group (HR: 0.73; 95%CI: 0.61–0.88), whereas no difference was observed in the rate of CVD death (HR: 0.98; 95%CI: 0.82–1.17). Moreover, dapagliflozin was noninferior to placebo with respect to major adverse CVD events. Dapagliflozin exerts beneficial effects on albuminuria. Additionally, in the DECLARE-TIMI 58 trial it significantly reduced the composite renal endpoint (40% decrease in glomerular filtration rate, end stage renal disease, or renal death) in both patients with established CVD and patients with multiple risk factors (overall HR: 0.53; 95%CI: 0.43–0.66). However dapagliflozin, like the other SGLT2 inhibitors, is associated with an increased risk of genital and urinary tract infections (usually mild mycotic infections) and acute kidney injury in cases of reduced extracellular volume. Dapagliflozin is a useful antidiabetic treatment which also exerts beneficial effects in the management of heart failure and diabetic kidney disease.

Sodium Glucose Co-transporter-2 Inhibitor: Benefits beyond Glycemic Control

Type 2 diabetes mellitus (T2DM) is a family of metabolic disorders characterized by hyperglycemia as a consequence of abnormalities in insulin secretion and insulin sensitivity. It affects hundreds of millions of people worldwide and leads to increased morbidity, compromised quality of life, higher mortality sodium glucose co-transporter 2 (SGLT2) inhibitors, a new class of oral antidiabetic drugs, have garnered considerable attention in the recent past and are considered potential first-line candidates for the management of T2DM. This review outlines the evidence-based therapeutic efficacy, safety, limitations, and advantages of SGLT2 inhibitors in the management of T2DM. SGLT2 inhibitors work by preventing the kidneys from reabsorbing glucose back into the blood, leading to increase in excretion of glucose through urine, thereby lowering hyperglycemia. Treatment with SGLT2 inhibitors improves A1C levels, reduces blood pressure and body weight, and is overall well tolerated by patients with T2DM. However, additional data on long-term cardiovascular safety are still needed. Characteristic adverse events include mild genital - urinary tract infection more commonly seen in women than in men, but serious infection is uncommon. Their use should be exercised with extra caution in patients suffering from renal impairment. Further, advancing to dual/triple combinational therapies with SGLT2 inhibitors and existing oral antidiabetic options may prove to be a breakthrough in the management of T2DM.

Dapagliflozin attenuates early markers of diabetic nephropathy in fructose-streptozotocin-induced diabetes in rats

Early detection and clinical interference are major challenges for the prevention of diabetic nephropathy (DN) progression. This study investigated the effects of dapagliflozin, a sodium glucose co-transporter 2 inhibitor, on some early markers for DN in fructose-streptozotocin (Fr-STZ)-induced diabetes in rats. Fr-STZ rats were treated with either dapagliflozin (1 mg/kg p.o. daily), metformin (350 mg/kg p.o. daily), or their combination for 6 weeks. Fr-STZ rats displayed marked early tubular renal damage and glomerular podocyte injury as evidenced by renal KIM-1, NGAL, cystatin C, and vanin-1 mRNA, as well as urinary NAG elevation and nephrin mRNA suppression, associated with the development of marked renal interstitial fibrosis and glomerulosclerosis despite the presence of normoalbuminuria. Propagation of oxidative, inflammatory, fibrotic, and apoptotic reactions was obvious in the setting of renal glucose overload. Dapagliflozin significantly attenuated the renal tubular injury makers namely KIM-1, NGAL, vanin-1 and urinary NAG. In addition, it restored glomerular nephrin expression and reversed renal histopathological changes. Oxidative, inflammatory, and fibrotic processes were also alleviated. This study suggests that dapagliflozin exerts a renoprotective effect against early features of DN in rats presumably by inhibition of diabetes-induced renal tubular and glomerular injury thereby modulating oxidative, inflammatory, and fibrotic as well as apoptotic mechanisms elicited during hyperglycemia.

Canagliflozin protects against non-alcoholic steatohepatitis in type-2 diabetic rats through zinc alpha-2 glycoprotein up-regulation

Elevated blood glucose and insulin resistance are triggering factors for non-alcoholic steatohepatitis (NASH). We investigated the effects of the Sodium Glucose co-Transporter 2 (SGLT2) inhibitor canagliflozin on NASH development in rats with type 2 diabetes mellitus as well as the possible underlying mechanisms and for the first time the effect of canagliflozin on the hepatic zinc-α2-glycoprotein (ZAG) levels. Rats were treated with nicotinamide and streptozotocin to reduce the insulin secretory capacity then fed high fat diet for 8 weeks. The diabetic high fat diet rats were divided into three groups; untreated group, canagliflozin 10 mg/kg treated group and canagliflozin 20 mg/kg treated group during this period. The elevated blood glucose and glycated haemoglobin (HbA1c) levels in the diabetic high fat diet rats were significantly reduced by canagliflozin. Moreover, the diabetic high fat diet induced NASH development as evidenced by liver weight gain, hepatic lipid accumulation and low hepatic ZAG expression as well as increased serum alanine aminotransferase; all these changes were reversed in rats treated with canagliflozin. Additionally, canagliflozin succeeded to upregulate the hepatic ZAG levels in both normal and diabetic high fat fed rats, lower the serum and hepatic inflammatory cytokines levels as well as lower the serum caspase-3 levels and enhanced hepatic Bcl-2 expression. Also, canagliflozin attenuated hepatic oxidative stress and elevated the antioxidant enzymes activity as well as the total antioxidant capacity. All these effects of canagliflozin were dose dependant.

CONCLUSION

SGLT2 inhibitor-canagliflozin- has beneficial effects in treatment of NASH associated with diabetes mellitus.

Current practices and future outlook on the integration of biomarkers in the drug development process

Over the last decade, there has been broad incorporation of translational biomarkers into the early drug development process to predict safety concerns, measure target engagement and monitor disease progression. One goal of translational biomarkers is to create a cycle whereby preclinical readouts influence candidate selection and subsequent clinical data are fed back into research to facilitate better decision making. Successes have been limited and not as broad in scope as desired. Collaborations between industry and regulators have increased the number of qualified biomarkers; but the process is lengthy and expensive. A high level overview of translational biomarkers as well as a discussion of some of the successes and failures encountered in development is discussed here.

SGLT-2 inhibitors: Their pleiotropic properties

Type 2 diabetes mellitus has become a global pandemic. Nowadays, it is estimated that approximately 415 million people all over the world have diabetes. The sodium glucose co-transporters 2 inhibitors are a new class of glucose-lowering agents, which act through a novel mechanism by producing a decline in glucose re-absorption in the kidney, thereby increasing glycosuria and decreasing serum glucose levels. Data suggest that apart from lowering HbA1c, they produce a small but significant weight loss and a small decrease in blood pressure. Also, they possess nephro-protective potential. These drugs are demonstrated to restore intra-glomerular pressure by increasing angiotensin (1-7), which exerts vasodilatory and anti-inflammatory effects. Their profile on cardiovascular events is still under investigation. In this review, the pleiotropic potential of this novel class of glucose-lowering levels will be discussed. Further research is warranted to determine their safety in the long term.

Durability of response to dapagliflozin: a review of long-term efficacy and safety

BACKGROUND

Due to the chronic nature of type 2 diabetes (T2D), it is essential for an anti-diabetic drug to have durable efficacy and a good long-term safety profile. Dapagliflozin is a member of a unique class of anti-diabetic drugs that inhibit the sodium-glucose cotransporter 2 (SGLT-2) in the renal tubules and have an insulin-independent mechanism of action. In short-term studies (≤ 24 weeks), dapagliflozin reduced glycated hemoglobin (A1c), weight, and systolic blood pressure, and had a good safety profile.

METHODS

This review summarizes the findings of long-term studies that evaluated the efficacy and safety of dapagliflozin.

RESULTS

These findings indicate that dapagliflozin is effective as monotherapy and in combination with other anti-hyperglycemic agents, including insulin and oral anti-diabetic therapies, in improving glycemic control and reducing blood pressure and weight for up to 4 years. The findings were fairly consistent across various patient populations with T2D, including those with cardiovascular disease (CVD) and mild renal impairment. Extended use of dapagliflozin was not associated with an increase in safety signals over time. Frequently observed adverse events (AEs) were consistent with the drug's mechanism of action and were generally mild in intensity. No substantial impact of dapagliflozin on renal function was observed, and findings show that the drug is safe in T2D patients with CVD or mild renal impairment, as well as elderly patients.

CONCLUSIONS

The findings across the studies support the use of dapagliflozin for the long-term treatment of T2D across a broad spectrum of patients.

Responses of renal hemodynamics and tubular functions to acute sodium-glucose cotransporter 2 inhibitor administration in non-diabetic anesthetized rats

The aim of this study is to examine the effects of acute administration of luseogliflozin, the sodium–glucose cotransporter 2 (SGLT2) inhibitor, on renal hemodynamics and tubular functions in anesthetized non-diabetic Sprague Dawley (SD) rats and 5/6 nephrectomized (Nx) SD rats. Renal blood flow (RBF), mean arterial pressure (MAP), and heart rate (HR) were continuously measured and urine was collected directly from the left ureter. Intraperitoneal injection of luseogliflozin (0.9 mg kg⁻¹) did not change MAP, HR, RBF, or creatinine clearance (CrCl) in SD rats (n = 7). Luseogliflozin significantly increased urine volume, which was associated with significantly increased urinary glucose excretion rates (P < 0.001). Similarly, luseogliflozin significantly increased urinary sodium excretion (from 0.07 ± 0.01 µmol min⁻¹ at baseline to 0.76 ± 0.08 µmol min⁻¹ at 120 min; P < 0.001). Furthermore, luseogliflozin resulted in significantly increased urinary pH (P < 0.001) and decreased urinary osmolality and urea concentration (P < 0.001) in SD rats. Similarly, in Nx SD rats (n = 5–6), luseogliflozin significantly increased urine volume and urinary glucose excretion (P < 0.001) without altering MAP, HR, RBF, or CrCl. Luseogliflozin did not elicit any significant effects on the other urinary parameters in Nx SD rats. These data indicate that SGLT2 inhibitor elicits direct tubular effects in non-diabetic rats with normal renal functions.

Use of GLP-1 receptor agonists for type 2 diabetes treatment intensification after basal insulin failure

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are part of the armamentarium for the treatment of type 2 diabetes (T2D), although recent guidelines have mainly recommended their use on top of oral treatments when a single or combination of two or three oral hypoglycaemic agents has failed to lower HbA_1c levels below the individualized target range. In such situations, the decision to use GLP-1RAs is mostly driven by their high level of efficacy, their effect on body weight balance and their safety considerations, such as low hypoglycaemic risk. According to the current guidelines, GLP-1RAs may also be used in T2D patients in addition to basal insulin, following specialist-care advice, in patients who are more severely obese or who may not have the capacity to handle the complexities of a multiple daily injection (MDI) insulin regimen. The present review looks at the scientific evaluations performed in this context as well as the clinical trials assessing the use of GLP-1RAs in combination with intensive insulin therapy as further step-up therapy.

Cost-effectiveness analysis of dapagliflozin versus glimepiride as monotherapy in a Chinese population with type 2 diabetes mellitus

OBJECTIVE

To evaluate the long-term cost-effectiveness of dapagliflozin (a novel sodium-glucose co-transporter-2 inhibitor) versus glimepiride (a widely used sulfonylurea), when applied as monotherapy in patients with type 2 diabetes mellitus (T2DM) in China.

METHODS

Literature screening, meta-analysis and indirect comparison were used to compare efficacy and safety between dapagliflozin and glimepiride. Direct medication costs and medical expenditure on treating diabetes related comorbidities were calculated based on published and local sources and reported in 2015 Chinese Renminbi (RMB). A discount rate of 3% was applied to both costs and health effects. The Cardiff model, an economic model designed to evaluate the cost-effectiveness of comparator therapies in diabetes, was used to generate outputs including macrovascular and microvascular complications, diabetes-specific mortality, costs and quality-adjusted life years (QALYs) over a time horizon of 40 years from the health provider perspective. Univariate and probabilistic sensitivity analyses were performed to assess uncertainty in the model results.

RESULTS

Compared with glimepiride, patients on dapagliflozin gained 1.01 QALYs, at a cost saving of RMB 49,065 in our simulated cohort. This resulted in a cost saving of RMB 48,585 per QALY gained with dapagliflozin. The cost-effectiveness results were robust to various sensitivity analyses including probabilistic sensitivity analysis (PSA).

CONCLUSIONS

Compared with glimepiride, dapagliflozin as monotherapy for T2DM is a more cost-effective treatment for T2DM patients on monotherapy in China. The weight control has been identified as the major contributor for the higher cost-effectiveness of dapagliflozin.

Quality measure attainment with dapagliflozin plus metformin extended-release as initial combination therapy in patients with type 2 diabetes: a post hoc pooled analysis of two clinical studies

Background

The use of quality measures attempts to improve safety and health outcomes and to reduce costs. In two Phase III trials in treatment-naive patients with type 2 diabetes, dapagliflozin 5 or 10 mg/d as initial combination therapy with metformin extended-release (XR) significantly reduced glycated hemoglobin (A_1C) from baseline to 24 weeks and allowed higher proportions of patients to achieve A_1C <7% vs dapagliflozin or metformin monotherapy.

Objective

A pooled analysis of data from these two studies assessed the effect of dapagliflozin 5 or 10 mg/d plus metformin XR (combination therapy) compared with placebo plus metformin XR (metformin monotherapy) on diabetes quality measures. Quality measures include laboratory measures of A_1C and low-density lipoprotein cholesterol (LDL-C) as well as vital status measures of blood pressure (BP) and body mass index (BMI). The proportion of patients achieving A_1C, BP, and LDL-C individual and composite measures was assessed, as was the proportion with baseline BMI ≥25 kg/m² who lost ≥4.5 kg. Subgroup analyses by baseline BMI were also performed.

Results

A total of 194 and 211 patients were treated with dapagliflozin 5- or 10-mg/d combination therapy, respectively, and 409 with metformin monotherapy. Significantly higher proportions of patients achieved A_1C ≤6.5%, <7%, or <8% with combination therapy vs metformin monotherapy (P<0.02). Significantly higher proportions of patients achieved BP <140/90 mmHg (P<0.02 for each dapagliflozin dose) and BP <130/80 mmHg (P<0.02 with dapagliflozin 5 mg/d only) with combination therapy vs metformin monotherapy. Similar proportions (29%–33%) of patients had LDL-C <100 mg/dL across treatment groups. A higher proportion of patients with baseline BMI ≥25 kg/m² lost ≥4.5 kg with combination therapy. Combination therapy had a more robust effect on patients with higher baseline BMI.

Conclusion

Initial combination therapy with dapagliflozin 5 or 10 mg/d and metformin improved quality measures relevant to clinical outcomes and diabetes care.

Switching from sulphonylurea to a sodium-glucose cotransporter2 inhibitor in the fasting month of Ramadan is associated with a reduction in hypoglycaemia

The aim of the present study was to assess the hypoglycaemia risk and safety of dapagliflozin compared with sulphonylurea during the fasting month of Ramadan. In this 12-week, randomized, open-label, two-arm parallel group study, 110 patients with type 2 diabetes who were receiving sulphonylurea and metformin were randomized either to receive 10 mg (n = 58) of dapagliflozin daily or to continue receiving sulphonylurea (n = 52). The primary outcome was to compare the effects of dapagliflozin and sulphonylurea on the proportions of patients with at least one episode of hypoglycaemia during Ramadan, as well as to assess the safety of dapagliflozin when used to treat patients observing Ramadan. A lower proportion of patients had reported or documented hypoglycaemia in the dapagliflozin group than in the sulphonylurea group: 4 (6.9%) versus 15 (28.8%); p = 0.002. The relative risk of any reported or documented hypoglycaemia in the 4th week of Ramadan was significantly lower in the dapagliflozin group: RR=0.24, 95%CI: 0.09, 0.68; p=0.002. No significance differences were observed between the two groups regarding postural hypotension (13.8 vs 3.8%; p = 0.210) or urinary tract infections (10.3 vs 3.8%; p = 0.277). In conclusion, fewer patients exhibited hypoglycaemia in the dapagliflozin group than in the sulphonylurea group.

Sodium-glucose cotransporter-2 inhibitor combination therapy to optimize glycemic control and tolerability in patients with type 2 diabetes: focus on dapagliflozin-metformin

In type 2 diabetes (T2D), early combination therapy using agents that target a number of the underlying pathophysiologic defects contributing to hyperglycemia may improve patient outcomes. For many patients, the combination of metformin with a sodium-glucose cotransporter-2 (SGLT-2) inhibitor may be a good option because these agents have complementary mechanisms of action, neutral-to-positive effects on body weight, and a low risk of hypoglycemia. This review focuses on the combination of metformin with dapagliflozin, a member of the SGLT-2 inhibitor class of antidiabetes agents. In clinical trials, the combination of dapagliflozin with metformin produced significant and sustained reductions in glycated hemoglobin and body weight in a broad range of adult patients with T2D, including those initiating pharmacotherapy and those with more advanced disease. These reductions were accompanied by modest decreases in blood pressure. Dapagliflozin as add-on therapy to metformin was well tolerated and associated with low rates of hypoglycemia. Genital infections and, in some studies, urinary tract infections were more frequent with dapagliflozin than with placebo. Early combination therapy with dapagliflozin and metformin may be a safe and appropriate treatment option that enables patients with T2D to achieve individualized glycemic goals as either initial combination therapy in treatment-naïve patients or as dapagliflozin add-on in patients inadequately controlled with metformin therapy.

Changes in HbA1c, body weight, and systolic blood pressure in type 2 diabetes patients initiating dapagliflozin therapy: a primary care database study

AIMS

To investigate changes in glycated hemoglobin (HbA1c), body weight (BW), and systolic blood pressure (SBP) in type 2 diabetes (T2D) primary care patients initiating dapagliflozin treatment.

METHODS

T2D patients who started dapagliflozin in 985 general and 32 diabetologist practices (Disease Analyzer, Germany: December 2012-October 2014) were analyzed (3- and 6-month follow-up). Multivariate linear regression analyses were used to identify clinical characteristics and comorbidity associated with changes in HbA1c, BW, and SBP.

RESULTS

The study included 1,169 T2D patients (age: 62.5 years; men: 59.3%; diabetologist care: 23%) with newly initiated dapagliflozin therapy. At the 3-month stage, dapagliflozin significantly reduced HbA1c (-0.8%±1.4%) compared to the baseline (8.5%±1.5%) (P<0.001). Changes were maintained after 6 months (-0.8%±1.5%) (P<0.001). Patients with high baseline HbA1c values (>9%) showed greater reductions in HbA1c than the overall sample (3 months -1.8%, 6 months -1.8%; both P<0.05). BW and SBP also showed statistically significant reductions with dapagliflozin over 3 and 6 months (-2.2 kg, P<0.001; -2.2 mmHg, P=0.003 and -2.5 kg, P<0.001; -2.3 mmHg, P=0.011, respectively). After 3 months, 53% of patients achieved a reduction in both HbA1c and BW; the same holds true for 45% of patients at the 6-month mark. Similar results were observed both in general and diabetologist practices. In multivariate analyses, baseline HbA1c (parameter estimate: -0.6479) and diabetologist care (-0.2553) were independent predictors of HbA1c change (6 months) (all P<0.05).

CONCLUSION

T2D patients treated with dapagliflozin therapy achieved statistically significant reductions in HbA1c, BW, and SBP in a real-world primary and diabetologist care setting. The changes were comparable to the results of the dapagliflozin clinical trial program.

Empagliflozin in the treatment of type 2 diabetes: evidence to date

In the last decade, researchers have gained a greater understanding of the pathophysiologic mechanisms of type 2 diabetes as a chronic and progressive disease. One of the more recent treatment targets is the kidney. The kidneys become maladaptive in diabetes by increasing the reabsorption of glucose above the normal physiologic renal threshold. This discovery has led to the development of the sodium/glucose cotransporter 2 inhibitors (SGLT2). These agents readjust the renal threshold for glucose reabsorption to a lower level and decrease glucose reabsorption, while increasing urinary glucose when the glucose is above the renal threshold and subsequently lowering plasma glucose. The mechanism of action of the SGLT2 inhibitors is insulin independent, which makes them a novel treatment of diabetes. At the time of preparation of this manuscript, there were three SGLT2 inhibitors available in the US. This manuscript focuses on empagliflozin, the newest SGLT2 inhibitor, the trials in its development, and the clinical data available to date. Further, the authors propose future applications of empagliflozin, including in the treatment of type 1 diabetes, and its potential role in renoprotection.

Dapagliflozin-induced weight loss affects 24-week glycated haemoglobin and blood pressure levels

The aim of this study was to investigate the associations between dapagliflozin-mediated reductions in body weight and reductions in glycated haemoglobin (HbA1c) and blood pressure. Data were pooled from seven studies evaluating dapagliflozin 10 mg as monotherapy or combination therapy over 24 weeks. Using linear regression to estimate the contribution of weight loss to HbA1c and blood pressure reductions, the β-value estimate for HbA1c (%)/kg was 0.028 (p < 0.0001). Weight loss of 2 kg with dapagliflozin contributed to 6% of the total HbA1c reduction. For systolic (SBP) and diastolic blood pressure (DBP), the β-value (mmHg/kg) estimates were 0.606 (p < 0.0001) and 0.253 (p < 0.0001), respectively. Weight loss of 2 kg contributed to 28% of the overall SBP reduction, and 24% of the overall DBP reduction. In conclusion, dapagliflozin-mediated weight loss may contribute to overall reductions in HbA1c and blood pressure.

Beyond Glycosuria: Exploring the intrarenal effects of SGLT₋₂ inhibition in diabetes

For millennia, the syndrome that has become known as diabetes was considered to be primarily a disease of the urinary system and, by association, of dysfunction in the kidneys (recognized as the source of urine). In the last decade, there has been renewed interest in the role of the kidneys in the development and maintenance of high glucose levels. This has led to the development of novel agents to inhibit sodiumglucose cotransporter 2 (SGLT-2) as a means to control glucose levels and augment calorie-wasting leading to weight loss. However, beyond actions on glycaemic control, inhibition of proximal glucose absorption via SGLT-2 has significant direct effects to attenuate hyperfiltration and reduce renal hypertrophy. Increased distal sodium delivery may also act to suppress the intrarenal renin-angiotensin-aldosterone system, although systemic activity may be modestly increased due to osmotic diuresis. Reducing proximal glucose reabsorption may also protect the tubular cells from exposure to excess glucose and glucose-induced reactive oxygen species. On the other hand, distal glucose delivery following inhibition of SGLT-2 may increase glycogen deposition, the significance of which is unclear. However, subjects with familial glycosuria appear to have a benign renal prognosis. Some studies have demonstrated significant reductions in albumin excretion in various experimental models and as post-hoc observations in clinical trials. Whether these reflect renoprotection or are simply the result of intraglomerular haemodynamic changes remains unclear. Although promising, such actions remain to be established by comprehensive clinical trials with a renal focus, many of which are currently in progress.

Safety profile of dapagliflozin for type 2 diabetes: pooled analysis of clinical studies for overall safety and rare events

BACKGROUND

Dapagliflozin reduces hyperglycaemia in patients with type 2 diabetes mellitus (T2DM) by increasing urinary glucose excretion.

OBJECTIVES

This study determined the overall safety profile of dapagliflozin in T2DM.

METHODS

Safety of dapagliflozin in pooled analyses of phase IIb/III studies was evaluated. Patients received comparator or dapagliflozin as monotherapy, add-on to antidiabetic therapy, or as initial combination with metformin. Proportions of patients with adverse events (AEs) and prespecified parameters related to previous clinical observations and dapagliflozin's action were assessed. The principal analysis used data from 12 placebo-controlled studies. Rare events were assessed across phase IIb/III studies, including special populations, comparator-controlled trials and ongoing long-term extensions.

RESULTS

In placebo-controlled studies, hypoglycaemia was more common with dapagliflozin (11.8 %) than placebo (7.0 %), with imbalance driven by add-on of dapagliflozin to sulfonylurea or insulin. Urinary tract infections (4.8 vs 3.7 %), vulvovaginitis/balanitis and related infections (5.1 vs 0.9 %), and non-serious volume-related events (0.8 vs 0.4 %) occurred more often with dapagliflozin than placebo. No substantial AEs were seen on electrolytes or renal function. Pyelonephritis was rare and balanced among treatments; there were no imbalances in fractures or liver test elevations. Overall incidence of malignancies was balanced between groups. The incidence rate ratios of malignancy in certain organ systems were slightly lower for dapagliflozin (renal tract, female reproductive) and in others were slightly lower for control (breast, prostate, bladder). Most AEs associated with dapagliflozin were mild/moderate and related to the mechanism of action.

CONCLUSION

Dapagliflozin has a favourable and predictable tolerability profile, with reported events related to its mechanism of action.

Dapagliflozin in patients with type 2 diabetes mellitus

Dapagliflozin is a selective and reversible inhibitor of sodium-glucose linked transporter type 2 (SGLT2), which mediates approximately 90% of active renal glucose reabsorption in the early proximal tubule of the kidney. Dapagliflozin significantly reduces glucose reabsorption and decreases serum glucose concentration in an insulin-independent manner. The decrease of glucose reabsorption by dapagliflozin has also been associated with a reduction in body weight. Furthermore, the drug modestly reduces blood pressure levels through weight loss and its action as osmotic diuretic. Dapagliflozin has been approved as monotherapy in patients with type 2 diabetes mellitus (T2DM) who cannot tolerate metformin or in combination with other antidiabetic drugs, with the exception of pioglitazone due to the theoretical increased risk of bladder cancer. The drug should not be prescribed in patients with moderate or severe renal impairment or in patients at risk for developing volume depletion. Dapagliflozin is associated with increased incidence of genital and lower urinary tract infections, but these infections are usually mild to moderate and respond to standard antimicrobial treatment. Based on current evidence, dapagliflozin is a useful drug for patients with T2DM with a favorable safety profile. However, further research regarding the effects of dapagliflozin on cardiovascular outcomes is needed.

Pharmacokinetics, pharmacodynamics and clinical efficacy of dapagliflozin for the treatment of type 2 diabetes

INTRODUCTION

Dapagliflozin (DAPA) (Farxiga or Forxiga) is a sodium glucose cotransporter 2 (SGLT2) inhibitor approved for type 2 diabetes mellitus(T2DM) treatment.

AREAS COVERED

The review focuses on the pharmacokinetics (PK), pharmacodynamics(PD) and clinical studies published on DAPA. The authors searched PubMed database for English language studies describing DAPA characteristics and use in T2DM subjects published through June 2014.

EXPERT OPINION

DAPA exhibits favorable PK and PD properties and is effective in reducing glycemic levels. In addition, DAPA shows beneficial/neutral effects on other risk factors contributing to T2DM metabolic control. Increased risk of genital and urinary infections and episodes of volume depletion represent the major concerns for its use. FDA requires additional data to assess imbalances in bladder cancer and drug cardiovascular safety. The mechanism of action and the very low risk of drug-drug interaction make it an ideal drug for rapidly reducing glucotoxicity and restoring clinical response to other antidiabetic drugs.

Effect of canagliflozin on serum electrolytes in patients with type 2 diabetes in relation to estimated glomerular filtration rate (eGFR)

OBJECTIVE

Effects of canagliflozin, a sodium glucose co-transporter 2 inhibitor, on serum electrolytes were evaluated using pooled data from studies of patients with type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS

Analyses were performed using two datasets, each including four placebo-controlled studies: Population 1 (N = 2215), patients with baseline estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m(2) (mean = 89.6 mL/min/1.73 m(2)) and Population 2 (N = 721), patients with baseline eGFR ≥45 and <60 mL/min/1.73 m(2) (mean = 53.3 mL/min/1.73 m(2)).

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT01081834; NCT01106625; NCT01106677; NCT01106690; NCT01032629; NCT01064414; NCT01106651.

MAIN OUTCOME MEASURES

Mean percent changes from baseline in serum electrolytes (potassium, sodium, magnesium, bicarbonate, phosphate, calcium) and outlier analyses were assessed in patients receiving canagliflozin 100 and 300 mg or placebo. Potassium changes were further evaluated based on baseline therapy with anti-hypertensive agents that interfere with potassium excretion (renin-angiotensin aldosterone system-acting agents and/or potassium-sparing diuretics).

RESULTS

Mean percent changes from baseline in potassium with canagliflozin 100 and 300 mg and placebo were 0.6%, 1.0%, and 0.5%, respectively (Week 26; Population 1); and 1.7%, 2.8%, and 0.7%, respectively (Week 18/26; Population 2). The proportion of patients who had potassium elevations meeting pre-defined outlier criteria (>5.4 mmol/L [5.4 mEq/L] and >15% increase from baseline) with canagliflozin 100 and 300 mg and placebo was 4.5%, 6.8%, and 4.7% (Population 1); and 5.2%, 9.1%, and 5.5% (Population 2). In both populations, potassium elevations were usually <6.5 mmol/L for patients treated with canagliflozin or placebo; elevations ≥6.5 mmol/L were rare but more frequent in patients taking anti-hypertensive agents that affect potassium excretion in both the canagliflozin and placebo groups. Small mean percent changes in sodium, bicarbonate, and calcium were seen across groups in both populations; small mean percent increases in magnesium and phosphate were seen with canagliflozin vs placebo, but without an increase in patients meeting outlier criteria. Adverse events related to changes in electrolytes were low across groups.

CONCLUSIONS

In patients with T2DM, canagliflozin was generally associated with small mean percent changes in serum electrolytes. Infrequent episodes of potassium elevation occurred with canagliflozin 300 mg, but occurred more often in patients with reduced eGFR.

Long-term treatment with the sodium glucose cotransporter 2 inhibitor, dapagliflozin, ameliorates glucose homeostasis and diabetic nephropathy in db/db mice

Inhibition of sodium glucose cotransporter 2 (SGLT2) has been reported as a new therapeutic strategy for treating diabetes. However, the effect of SGLT2 inhibitors on the kidney is unknown. In addition, whether SGLT2 inhibitors have an anti-inflammatory or antioxidative stress effect is still unclear. In this study, to resolve these issues, we evaluated the effects of the SGLT2 inhibitor, dapagliflozin, using a mouse model of type 2 diabetes and cultured proximal tubular epithelial (mProx24) cells. Male db/db mice were administered 0.1 or 1.0 mg/kg of dapagliflozin for 12 weeks. Body weight, blood pressure, blood glucose, hemoglobin A1c, albuminuria and creatinine clearance were measured. Mesangial matrix accumulation and interstitial fibrosis in the kidney and pancreatic β-cell mass were evaluated by histological analysis. Furthermore, gene expression of inflammatory mediators, such as osteopontin, monocyte chemoattractant protein-1 and transforming growth factor-β, was evaluated by quantitative reverse transcriptase-PCR. In addition, oxidative stress was evaluated by dihydroethidium and NADPH oxidase 4 staining. Administration of 0.1 or 1.0 mg/kg of dapagliflozin ameliorated hyperglycemia, β-cell damage and albuminuria in db/db mice. Serum creatinine, creatinine clearance and blood pressure were not affected by administration of dapagliflozin, but glomerular mesangial expansion and interstitial fibrosis were suppressed in a dose-dependent manner. Dapagliflozin treatment markedly decreased macrophage infiltration and the gene expression of inflammation and oxidative stress in the kidney of db/db mice. Moreover, dapagliflozin suppressed the high-glucose-induced gene expression of inflammatory cytokines and oxidative stress in cultured mProx24 cells. These data suggest that dapagliflozin ameliorates diabetic nephropathy by improving hyperglycemia along with inhibiting inflammation and oxidative stress.

Renal effects of dapagliflozin in patients with type 2 diabetes

Diabetes mellitus was originally conceived as a renal disorder. In the last decade, however, there has been renewed interest in role of the kidney in the development and maintenance of high glucose levels. This has led to the development of novel agents to inhibit sodium glucose transporter-2 (SGLT2) as a means to better control glucose levels and at the same time augment calorie wasting and lower insulin, blood pressure and uric acid levels. Such actions, indirectly, may also have benefits for the prevention of diabetic complications including renal disease. However, there are also data to support the potential for direct renoprotective actions arising from inhibition of SGLT2, including actions to attenuate diabetes-associated hyperfiltration and tubular hypertrophy, as well as reduce the tubular toxicity of glucose. Some studies have demonstrated significant reductions in albumin excretion in various experimental models, independent of its effects on blood pressure or glucose control. Although promising, such actions remain to be established by comprehensive clinical trials with a renal focus, many of which are currently in progress. This article reviews the clinical and experimental data pertaining to the renal effects of SGLT2 inhibition with a particular focus on dapaglifozin.

Dapagliflozin compared with other oral anti-diabetes treatments when added to metformin monotherapy: a systematic review and network meta-analysis

AIMS

Indirect evidence from randomized controlled trials (RCTs) was used to estimate the effect of dapagliflozin, a new agent with a novel mechanism of action (SGLT-2 inhibition), relative to other anti-diabetes therapies after 1 year of treatment.

METHODS

A systematic literature review and Bayesian network meta-analysis (NMA) of RCTs involving anti-diabetes treatments added to metformin were conducted. RCTs enrolling subjects with type 2 diabetes inadequately controlled on metformin monotherapy were included. Comparators included dipeptidyl peptidase-4 (DPP-4) inhibitors, thiazolidinediones (TZDs), sulphonylureas, glucagon-like peptide-1 (GLP-1) analogues and dapagliflozin. Outcomes of interest were mean change from baseline HbA1c, weight and systolic blood pressure, and incidence of hypoglycaemia.

RESULTS

From 4270 abstracts, six RCTs were included in the primary analysis; no RCTs involving GLP-1 analogues met primary inclusion criteria. All RCTs were actively controlled with sulphonylureas. The mean change in HbA1c from baseline was similar across comparators. The treatment effect (95% credible interval) of dapagliflozin on HbA1c was -0.08% (-0.25, 0.10) relative to DPP-4 inhibitors, -0.02% (-0.24, 0.21) relative to TZDs and 0.00% (-0.16, 0.16) relative to sulphonylureas. Non-sulphonylureas showed significantly lower risk of hypoglycaemia relative to sulphonylureas. Dapagliflozin had a significant effect on weight change: the relative difference was -2.74 kg (-5.35, -0.10) compared with DPP-4 inhibitors, and -4.67 kg (-7.03, -2.35) compared with sulphonylureas. Systolic blood pressure was not meta-analysed due to infrequent reporting.

CONCLUSION

Compared with DPP-4 inhibitors, TZDs and sulphonylureas, dapagliflozin offers similar HbA1c control after 1 year, with similar or reduced risk of hypoglycaemia and the additional benefit of weight loss, when added to metformin.

Health-related quality of life (EQ-5D) among type 2 diabetes mellitus patients treated with dapagliflozin over 2 years

AIMS

This study evaluated health status and health-related quality of life (HRQOL) among patients with type 2 diabetes mellitus (T2DM) treated with dapagliflozin, a highly selective sodium-glucose co-transporter 2 (SGLT2) inhibitor that lowers blood glucose by increasing glucose excretion, in a double-blind, randomised clinical trial.

METHODS

Subjects with T2DM who had inadequate glycaemic control on metformin alone were enrolled in a 24-week, double-blind, randomised, placebo-controlled study with a 78-week extension period to evaluate the effect of dapagliflozin in combination with metformin. Subjects treated with dapagliflozin 10 mg + metformin (n = 89) were compared with subjects treated with placebo + metformin (n = 91) at baseline and at weeks 24, 50 and 102. EQ-5D change from baseline was derived from a repeated-measures mixed model, adjusting for baseline EQ-5D, treatment group, time point and use of rescue medication.

RESULTS

Mean (SD) EQ-5D index was 0.85 (0.16) and 0.82 (0.15) at baseline and 0.85 (0.19) and 0.84 (0.19) at week 102 for dapagliflozin and placebo, respectively. The model indicated no change over 102 weeks in EQ-5D index scores in either treatment group. Mean (SD) EQ-5D visual analogue scale (VAS) was 72.5 (19.5) and 73.7 (15.6) at baseline and 79.8 (13.3) and 78.2 (12.1) at week 102 for dapagliflozin and placebo, respectively. The model indicated similar small improvements in EQ-5D VAS scores in both groups over 102 weeks.

CONCLUSION

Patients maintained high HRQOL scores from baseline through week 102 in both treatment groups. Dapagliflozin, a novel SGLT2 inhibitor, did not adversely affect HRQOL over 2 years of treatment.

Combined antidiabetic benefits of exenatide and dapagliflozin in diabetic mice

The combined glucose-lowering effect of exenatide and dapagliflozin has not yet been studied. We investigated this combination (single-dose or 4-week dosing) in diabetic ob/ob mice. Vehicle-corrected basal glucose showed greater reduction 1 h following exenatide + dapagliflozin than with exenatide or dapagliflozin alone, and stayed significantly lower for all groups versus vehicle over 3 h. During an oral glucose tolerance test, glucose excursion (30 min post-dose) was significantly lower for exenatide + dapagliflozin versus exenatide or dapagliflozin, or vehicle. Exenatide + dapagliflozin and exenatide, but not dapagliflozin alone, reduced glucose excretion over 24 h versus vehicle. After dosing for 4 weeks, exenatide, dapagliflozin and exenatide + dapagliflozin similarly decreased haemoglobin A1c (HbA1c). Body weight was reduced only with exenatide or exenatide + dapagliflozin. The glomerular filtration rate was similar with exenatide, dapagliflozin and vehicle, and increased with exenatide + dapagliflozin. Optimized combinatorial dosing of these antidiabetic agents may provide additive glucose lowering in type 2 diabetes mellitus.

Diabetic kidney disease and the cardiorenal syndrome: old disease, new perspectives

In this article, the literature is reviewed regarding the role of blood pressure variability and nocturnal nondipping of blood pressure as well as the presence of diabetic kidney disease (DKD), in the absence of albuminuria, as risk predictors for progressive DKD. The importance of glycemic and blood pressure control in patients with diabetes and chronic kidney disease, and the use of oral hypoglycemic agents and antihypertensive agents in this patient cohort, are also discussed.

Nonclinical Toxicology Assessments Support the Chronic Safety of Dapagliflozin, a First-in-Class Sodium-Glucose Cotransporter 2 Inhibitor

Dapagliflozin, a first-in-class, selective inhibitor of sodium-glucose cotransporter 2 (SGLT2), promotes urinary glucose excretion to reduce hyperglycemia for the treatment of type 2 diabetes. A series of nonclinical studies were undertaken to evaluate dapagliflozin in species where it was shown to have pharmacologic activity comparable with that in humans at doses that resulted in supratherapeutic exposures. In vitro screening (>300 targets; 10 μmol/L) indicated no significant off-target activities for dapagliflozin or its primary human metabolite. Once daily, orally administered dapagliflozin was evaluated in Sprague-Dawley rats (≤6 months) and in beagle dogs (≤1 year) at exposures >5000-fold those observed at the maximum recommended human clinical dose (MRHD; 10 mg). Anticipated, pharmacologically mediated effects of glucosuria, osmotic diuresis, and mild electrolyte loss were observed, but there were no adverse effects at clinically relevant exposures, including in the kidneys or urogenital tract. The SGLT2−/− mice, which show chronic glucosuria, and dapagliflozin-treated, wild-type mice exhibited similar safety profiles. In rats but not dogs, dapagliflozin at >2000-fold MRHD exposures resulted in tissue mineralization and trabecular bone accretion. Investigative studies suggested that the effect was not relevant to human safety, since it was partially related to off-target inhibition of SGLT1, which was observed only at high doses of dapagliflozin and resulted in intestinal glucose malabsorption and increased intestinal calcium absorption. The rigorous assessment of supra- and off-target dapagliflozin pharmacology in nonclinical species allowed for a thorough evaluation of potential toxicity, providing us with confidence in its safety in patients with diabetes.

Treating the obese diabetic

Type 2 diabetes and obesity are intimately linked; reduction of bodyweight improves glycemic control, mortality and morbidity. Treating obesity in the diabetic is hampered as some diabetic treatments lead to weight gain. Bariatric surgery is currently the most effective antiobesity treatment and causes long-term remission of diabetes in many patients. However, surgery has a high cost and is associated with a significant risk of complications, and in practical terms only limited numbers can undergo this therapy. The choice of pharmacological agents suitable for treatment of diabetes and obesity is currently limited. The glucagon-like peptide-1 receptor agonists improve glycemia and induce a modest weight loss, but there are doubts over their long-term safety. New drugs such as lorcaserin and phentermine/topiramate are being approved for obesity and have modest, salutary effects on glycemia, but again long-term safety is unclear. This article will also examine some future avenues for development, including gut hormone analogues that promise to combine powerful weight reduction with beneficial effects on glucose metabolism.

Complementing insulin therapy to achieve glycemic control

INTRODUCTION

Most patients with type 2 diabetes mellitus (T2DM) will need incrementally more complex therapeutic regimens to control hyperglycemia as the disease progresses. Insulin is very effective in reducing hyperglycemia and may improve β-cell function in patients with T2DM. However, insulin therapy is associated with weight gain and increased risk of hypoglycemia. Adding other antidiabetes medications to insulin can improve glycemic control and potentially lower the required insulin dose, resulting in less weight gain and lower risk for hypoglycemia. This article summarizes the advantages and disadvantages of different classes of commonly used antidiabetes agents, with emphasis on newer classes, for use as add-on therapy to insulin in patients with T2DM inadequately controlled on insulin therapy.

METHODS

A PubMed search from July 1, 2003 to April 15, 2013 for peer-reviewed clinical and review articles relevant to insulin combination or add-on therapy in T2DM was conducted. Search terms included "insulin combination therapy," "add-on therapy diabetes," "dipeptidyl peptidase-4 (DPP-4) inhibitors," "glucagon-like peptide-1 (GLP-1) receptor agonist," "sodium-glucose cotransporter 2 (SGLT2) inhibitors", "insulin metformin," "insulin sulfonylurea," and "insulin thiazolidinedione." Bibliographies from retrieved articles were also searched for relevant articles. Study design, clinical relevance, and effect on insulin combination therapy were analyzed.

RESULTS

Therapies used as add-on to insulin include agents associated with weight gain (thiazolidinediones and sulfonylureas) and/or hypoglycemia (sulfonylureas), which, therefore, may exacerbate risks already present with insulin. GLP-1 receptor agonists, DPP-4 inhibitors, and SGLT2 inhibitors improve glycemic control when added to insulin and have a low propensity for hypoglycemia and cause no change (DPP-4 inhibitors) or a reduction (GLP-1 receptor agonists, SGLT2 inhibitors) in body weight.

CONCLUSION

GLP-1 receptor agonists, DPP-4 inhibitors, and SGLT2 inhibitors improve glycemic control when combined with insulin. They also have low propensity for weight gain and hypoglycemia and so may be preferred treatment options for insulin combination when compared with traditional therapies.

Differentiating sodium-glucose co-transporter-2 inhibitors in development for the treatment of type 2 diabetes mellitus

INTRODUCTION

Sodium-glucose co-transporter-2 (SGLT2) inhibitors are a novel class of agents for the treatment of type 2 diabetes mellitus (T2DM). By inhibiting SGLT2, they prevent renal glucose reabsorption, resulting in glucosuria.

AREAS COVERED

The rationale for development of SGLT2 inhibitors is reviewed, with particular focus on the nine SGLT2 inhibitors currently in development. The authors compare the potency and SGLT2 selectivity of the agents, as well as the results from both animal and clinical studies, considering the potential implications they may have for clinical use.

EXPERT OPINION

Current evidence suggests that SGLT2 inhibitors have similar efficacy in terms of glycemic control and also demonstrate benefits beyond glycemic reductions, including reductions in body weight and modest reductions in blood pressure. Additionally, they appear to preserve beta-cell function and improve insulin sensitivity. Their mechanism of action allows for combination of SGLT2 inhibitors with other antidiabetic drugs and use across the treatment continuum for T2DM. Potential differences in safety and efficacy based on observed differences in potency and selectivity among the SGLT2 inhibitors, particularly versus SGLT1, remain to be seen. Further long-term data, including post-marketing surveillance, are required to fully determine the safety profile of SGLT2 inhibitors in large patient groups.