Multiple-dose pharmacokinetics and pharmacodynamics of sergliflozin etabonate, a novel inhibitor of glucose reabsorption, in healthy overweight and obese subjects: a randomized double-blind study

Recent Advances in the Development of Type 2 Sodium-Glucose Cotransporter Inhibitors for the Treatment of Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is one of the most serious and prevalent diseases worldwide. In the last decade, type 2 sodium-glucose cotransporter inhibitors (iSGLT2) were approved as alternative drugs for the pharmacological treatment of T2DM. The anti-hyperglycemic mechanism of action of these drugs involves glycosuria. In addition, SGLT2 inhibitors cause beneficial effects such as weight loss, a decrease in blood pressure, and others.

OBJECTIVE

This review aimed to describe the origin of SGLT2 inhibitors and analyze their recent development in preclinical and clinical trials.

RESULTS

In 2013, the FDA approved SGLT2 inhibitors as a new alternative for the treatment of T2DM. These drugs have shown good tolerance with few adverse effects in clinical trials. Additionally, new potential anti-T2DM agents based on iSGLT2 (O-, C-, and N-glucosides) have exhibited a favorable profile in preclinical evaluations, making them candidates for advanced clinical trials.

CONCLUSION

The clinical results of SGLT2 inhibitors show the importance of this drug class as new anti-T2DM agents with a potential dual effect. Additionally, the preclinical results of SGLT2 inhibitors favor the design and development of more selective new agents. However, several adverse effects could be a potential risk for patients.

Sodium-Glucose Co-Transporter-2 Inhibitors in Non-Diabetic Adults With Overweight or Obesity: A Systematic Review and Meta-Analysis

BACKGROUND

Sodium-glucose-cotransporter-2 (SGLT2) inhibitors have proven to be effective in improving glycemic control and lowering body weight in patients with type 2 diabetes mellitus. However, the efficacy and safety on weight loss in adults with overweight or obesity but not diabetes remain unclear. In this article, we aimed to identify the efficacy and safety of SGLT2 inhibitors in adults with overweight or obesity but not diabetes in randomized controlled studies (RCTs).

METHODS

We searched for RCTs concerning SGLT2 inhibitors in adults with overweight or obesity but not diabetes in Medline (Ovid SP), Embase (Ovid SP), Cochrane Central Register of Controlled Trials (Ovid SP), and ClinicalTrials.gov up to February 2021. The primary outcomes were changes in body weight and body mass index (BMI). Trial sequential analysis (TSA) was used to test the reliability of the primary outcomes. We analyzed the data using Review Manager 5.3 and pooled data to calculate the mean differences (MDs) or the relative risk (RR). We assessed the evidence quality of evidence of outcomes according to GRADE.

RESULTS

Six randomized controlled trials involving 872 individuals were included in the meta-analysis. Compared to the placebo group, the SGLT2 inhibitors group had statistically significant reductions in absolute changes in body weight (MD: -1.42 kg, 95% CI: -1.70 to -1.14; P<0.00001) and BMI (MD: -0.47 kg/m2, 95% CI: -0.63 to -0.31; P<0.00001) in SGLT2 inhibitors group, as indicated by TSA. However, no significant benefits were observed in the SGLT2 inhibitors group in terms of waist circumference (MD: -1.34 cm, 95%CI: -2.75 to 0.07; Z=1.86, P=0.06) compared with the placebo group. The GRADE profiles indicated very low-quality evidence for body weight change and low-quality evidence for BMI change. SGLT2 inhibitors were generally safe and well tolerated.

CONCLUSION

SGLT2 inhibitors could be used in selected adults with overweight and obesity but not diabetes if they are at low risk of genital infection and urinary infection. Further studies are warranted to confirm the efficacy and safety of SGLT2 inhibitors in adults with overweight or obesity but not diabetes for long-term weight management.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/#loginpage], identifier [PROSPERO, CRD42021252931].

Effects of Dapagliflozin on Endothelial Function, Renal Injury Markers, and Glycemic Control in Drug-Naïve Patients with Type 2 Diabetes Mellitus

BACKGROUND

The study aimed to evaluate the effects of dapagliflozin and metformin on vascular endothelial function and renal injury markers.

METHODS

This prospective, randomized, open-label, crossover study included drug-naïve patients with type 2 diabetes mellitus, who were randomized to receive 8 weeks of initial treatment using metformin or dapagliflozin and crossed over for another 8 weeks of treatment after a 1-week washout period. Systemic endothelial function was evaluated via the reactive hyperemic index (RHI).

RESULTS

The 22 participants included 10 males (45.5%) and had a median age of 58 years. The RHI values were not significantly changed during both 8-week treatment periods and there was no significant difference between the treatments. Relative to the metformin group, 8 weeks of dapagliflozin treatment produced significantly higher median N-acetyl-beta-D-glucosaminidase levels (10.0 ng/mL [interquartile range (IQR), 6.8 to 12.1 ng/mL] vs. 5.6 ng/mL [IQR, 3.8 to 8.0 ng/mL], P=0.013). Only the dapagliflozin group exhibited improved homeostatic model assessment of insulin resistance and body weight, while serum ketone and β-hydroxybutyrate levels increased.

CONCLUSION

Dapagliflozin treatment did not affect systemic endothelial function or renal injury markers except N-acetyl-beta-D-glucosaminidase.

Recent progress of sodium-glucose transporter 2 inhibitors as potential antidiabetic agents

SGLT2 inhibitors were promising and novel antidiabetic drugs which suppressed glucose reabsorption and increased urinary glucose exertion. This review paper are aimed to summarize the recent progress of SGLT2 inhibitors during the last 5 years. This paper first summarizes the information of SGLT2 inhibitors, including mechanism, evolution and then focuses on the recent efforts on structure-activity relationships and structural optimization of SGLT2 inhibitors. Finally, the corresponding clinical therapeutic efficacy and adverse drug reaction in patients with Type 2 diabetes are discussed in detail.

Comparative pharmacokinetics of three SGLT-2 inhibitors sergliflozin, remogliflozin and ertugliflozin: an overview

1. Several sodium-glucose cotransporter-2 (SGLT-2) inhibitors are in clinical use for the management of type 2 diabetes. The objectives of the current review were: (a) to provide a comparative pharmacokinetics including absorption, distribution, metabolism and excretory (ADME) profiles of three SGLT-2 inhibitors namely: sergliflozin, remogliflozin and ertugliflozin; (b) to provide some perspectives on possible developmental issues. 2. Based on the half-life (t_1/2) values observed in humans, the rank order of the three SGLT-2 inhibitors was ertugliflozin (16 h) > remogliflozin (2-4 h) > sergliflozin (1-1.5 h). Therefore, while once a day dosing of ertugliflozin is possible, the other two drugs need to be dosed more frequently. Perhaps, the short t_1/2 of sergliflozin may have contributed for its discontinuation. 3. Although there was paucity of published data on the metabolism, transporter related and excretory aspects for sergliflozin, the other two drugs provided a differentiating profile. However, the compiled data suggested that there may be a minimal or no risk of pharmacokinetic drug interaction issues associated with any of the reviewed drugs. 4. Because of the crowded development pipeline and approved SGLT-2 inhibitors, the safety and efficacy of sergliflozin, remogliflozin and ertugliflozin appear to be a key from differentiation perspective.

Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitors from Natural Products: Discovery of Next-Generation Antihyperglycemic Agents

Diabetes mellitus is a chronic condition associated with the metabolic impairment of insulin actions, leading to the development of life-threatening complications. Although many kinds of oral antihyperglycemic agents with different therapeutic mechanisms have been marketed, their undesirable adverse effects, such as hypoglycemia, weight gain, and hepato-renal toxicity, have increased demand for the discovery of novel, safer antidiabetic drugs. Since the important roles of the sodium-glucose cotransporter 2 (SGLT2) for glucose homeostasis in the kidney were recently elucidated, pharmacological inhibition of SGLT2 has been considered a promising therapeutic target for the treatment of type 2 diabetes. Since the discovery of the first natural SGLT2 inhibitor, phlorizin, several synthetic glucoside analogs have been developed and introduced into the market. Furthermore, many efforts to find new active constituents with SGLT2 inhibition from natural products are still ongoing. This review introduces the history of research on the development of early-generation SGLT2 inhibitors, and recent progress on the discovery of novel candidates for SGLT2 inhibitor from several natural products that are widely used in traditional herbal medicine.

Clinical implication of SGLT2 inhibitors in type 2 diabetes

Treatment of type 2 diabetes mellitus (T2DM) continues to present challenges, with many patients failing to achieve glycemic targets. Despite the availability of many oral and injectable anti-diabetic agents, therapeutic efficacy is often offset by undesirable side effects such as hypoglycemia, weight gain and cardiovascular complications. Therefore, the search for new therapeutic agents with an improved benefit-risk profile continues. Recent research has focused on the kidney as a potential therapeutic target, especially because maximal renal glucose reabsorption is increased in T2DM. Under normal physiological conditions, nearly all filtered glucose is reabsorbed in the proximal tubule of the nephron via the sodium/glucose co-transporter 2 (SGLT2). SGLT2-inhibitors are a new class of oral anti-diabetes, which reduce hyperglycemia by increasing urinary glucose excretion independently of insulin secretion or action. Canagliflozin and dapagliflozin in US market, and ipragliflozin and luseogliflozin in Japan market are now available for glycemic control in type 2 diabetics. There are several phase III clinical ongoing trials involving this new class of medications. This review examines some of the key efficacy and safety data from clinical trials of the SGLT2 inhibitors approved, and their future perspectives in the treatment of T2DM.

SGLT-2 Inhibitors: A New Mechanism for Glycemic Control

Glucosuria, the presence of glucose in the urine, has long been regarded as a consequence of uncontrolled diabetes. However, glucose excretion can be induced by blocking the activity of the renal sodium-glucose cotransporter 2 (SGLT-2). This mechanism corrects hyperglycemia independently of insulin. This article provides an overview of the paradigm shift that triggered the development of the SGLT-2 inhibitor class of agents and summarizes the available evidence from clinical studies to date.

Exploring glycosuria as a mechanism for weight and fat mass reduction. A pilot study with remogliflozin etabonate and sergliflozin etabonate in healthy obese subjects

Inhibitors of sodium-dependent glucose co-transporter 2 (SGLT2) increase glucose excretion in the urine and improve blood glucose in Type 2 diabetes mellitus. Glycosuria provides an energy and osmotic drain that could alter body composition. We therefore conducted a pilot study comparing the effects on body composition of two SGLT2 inhibitors, remogliflozin etabonate (RE) 250 mg TID (n = 9) and sergliflozin etabonate (SE) (1000 mg TID) (n = 9), with placebo (n = 12) in obese non-diabetic subjects. Both drugs were well tolerated during 8 weeks of dosing, and the most common adverse event was headache. No urinary tract infections were observed, but there was one case of vaginal candidiasis in the RE group. As expected, RE and SE increased urine glucose excretion, with no change in the placebo group. All the subjects lost weight over 8 weeks, irrespective of treatment assignment. There was a reduction in TBW measured by D₂O dilution in the RE group that was significantly greater than placebo (1.4 kg, p = 0.029). This was corroborated by calculation of fat-free mass using a quantitative magnetic resonance technique. All but one subject had a measurable decrease in fat mass. There was significant between-subject variability of weight and fat loss, and no statistically significant differences were observed between groups. Despite a lack of a difference in weight and fat mass loss, the leptin/adiponectin ratio, a measure of insulin resistance, was significantly decreased in the RE group when compared to placebo and SE, suggesting that this SGTL-2 inhibitor may improve metabolic health independent of a change in fat mass.

Inhibition of the sodium glucose co-transporter-2: its beneficial action and potential combination therapy for type 2 diabetes mellitus

Sodium glucose co-transporter-2 (SGLT2) inhibitors are an emerging class of glucose-lowering drugs in the management of type 2 diabetes mellitus (T2DM). In this context, SGLT2 is a low-affinity, high-capacity transporter that is expressed predominantly in the proximal renal tubules. The rationale for using SGLT2 inhibition as a drug for T2DM is derived from early evidence obtained from individuals with familial renal glycosuria, due to a SGLT2 mutation, which exhibits decreased renal tubular reabsorption of glucose in the absence of hyperglycaemia or any other signs of dysfunction. Thus, reduction of glucose reabsorption by SGLT2 inhibition represents a novel T2DM treatment approach. In light of the emerging role of SGLT2 inhibition in controlling glucose homeostasis, the current review provides a critical appraisal of the rationale, overviews of structural differences between SGLT2 inhibitors and summarizes recent preclinical and clinical studies. The physiological actions of SGLT2 inhibition in relation to insulin sensitivity, islet morphology, inflammation, body weight and blood pressure are reviewed. Finally, the safety and tolerability of SGLT2 inhibitors are also discussed in relation to their potential to provide insulin independence and enhance β-cell function, as well as their potential for synergistic/additive effects if used in combination with other antidiabetic drugs.

Safety, pharmacokinetics and pharmacodynamics of remogliflozin etabonate, a novel SGLT2 inhibitor, and metformin when co-administered in subjects with type 2 diabetes mellitus

Background

The sodium-dependent glucose co-transporter-2 (SGLT2) is expressed in absorptive epithelia of the renal tubules. Remogliflozin etabonate (RE) is the prodrug of remogliflozin, the active entity that inhibits SGLT2. An inhibitor of this pathway would enhance urinary glucose excretion (UGE), and potentially improve plasma glucose concentrations in diabetic patients. RE is intended for use for the treatment of type 2 diabetes mellitus (T2DM) as monotherapy and in combination with existing therapies. Metformin, a dimethylbiguanide, is an effective oral antihyperglycemic agent widely used for the treatment of T2DM.

Methods

This was a randomized, open-label, repeat-dose, two-sequence, cross-over study in 13 subjects with T2DM. Subjects were randomized to one of two treatment sequences in which they received either metformin alone, RE alone, or both over three, 3-day treatment periods separated by two non-treatment intervals of variable duration. On the evening before each treatment period, subjects were admitted and confined to the clinical site for the duration of the 3-day treatment period. Pharmacokinetic, pharmacodynamic (urine glucose and fasting plasma glucose), and safety (adverse events, vital signs, ECG, clinical laboratory parameters including lactic acid) assessments were performed at check-in and throughout the treatment periods. Pharmacokinetic sampling occurred on Day 3 of each treatment period.

Results

This study demonstrated the lack of effect of RE on steady state metformin pharmacokinetics. Metformin did not affect the AUC of RE, remogliflozin, or its active metabolite, GSK279782, although C_max values were slightly lower for remogliflozin and its metabolite after co-administration with metformin compared with administration of RE alone. Metformin did not alter the pharmacodynamic effects (UGE) of RE. Concomitant administration of metformin and RE was well tolerated with minimal hypoglycemia, no serious adverse events, and no increase in lactic acid.

Conclusions

Coadministration of metformin and RE was well tolerated in this study. The results support continued development of RE as a treatment for T2DM.

Trial registration

ClinicalTrials.gov, NCT00376038

Synthesis and biological evaluation of C-glucosides with azulene rings as selective SGLT2 inhibitors for the treatment of type 2 diabetes mellitus: discovery of YM543

Here, a series of C-glucosides with azulene rings in the aglycon moiety was synthesized and the inhibitory activities toward hSGLT1 and hSGLT2 were evaluated. Starting from the azulene derivative 7 which had relatively good SGLT2 inhibitory activity, compound 8a which has a 3-[(azulen-2-yl)methyl]phenyl group was identified as a lead compound for further optimization. Introduction of a phenolic hydroxyl group onto the central benzene ring afforded a potent and selective SGLT2 inhibitor 8e, which reduced blood glucose levels in a dose-dependent manner in rodent diabetic models. A mono choline salt of 8e (YM543) was selected as a clinical candidate for use in treating type 2 diabetes mellitus.

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.

In vitro-in vivo correlation of the inhibition potency of sodium-glucose cotransporter inhibitors in rat: a pharmacokinetic and pharmacodynamic modeling approach

To evaluate the relationship between the in vitro and in vivo potency of sodium-glucose cotransporter (SGLT) inhibitors, a pharmacokinetic and pharmacodynamic (PK-PD) study was performed using normal rats. A highly selective SGLT2 inhibitor, tofogliflozin, and four other inhibitors with different in vitro inhibition potency to SGLT2 and selectivity toward SGLT2, versus SGLT1 were used as test compounds, and the time courses for urinary glucose excretion (UGE) and the plasma glucose and compound concentrations were monitored after administration of the compounds. A PK-PD analysis of the UGE caused by SGLT inhibition was performed on the basis of a nonlinear parallel tube model that took into consideration the consecutive reabsorption by different glucose transport properties of SGLT2 and SGLT1. The model adequately captured the time course of cumulative UGE caused by SGLT inhibition; then, the in vivo inhibition constants (Ki) of inhibitors for both SGLT1 and SGLT2 were estimated. The in vivo selectivity toward SGLT2 showed a good correlation with the in vitro data (r = 0.985; P < 0.05), with in vivo Ki values for SGLT2 in the range of 0.3-3.4-fold the in vitro data. This suggests that in vitro inhibition potency to both SGLT2 and SGLT1 is reflected in vivo. Furthermore, the complementary role of SGLT1 to SGLT2 and how selectivity toward SGLT2 affects the inhibitory potency for renal glucose reabsorption were discussed using the PK-PD model.

On the importance of synthetic organic chemistry in drug discovery: reflections on the discovery of antidiabetic agent ertugliflozin

The discovery of antidiabetic agent ertugliflozin is described. In this article, emphasis is placed on the critical role that organic synthesis played in influencing our medicinal chemistry strategy.

Pharmacotherapy for childhood obesity: present and future prospects

Pediatric obesity is a serious medical condition associated with significant comorbidities during childhood and adulthood. Lifestyle modifications are essential for treating children with obesity, yet many have insufficient response to improve health with behavioral approaches alone. This review summarizes the relatively sparse data on pharmacotherapy for pediatric obesity and presents information on obesity medications in development. Most previously studied medications demonstrated, at best, modest effects on body weight and obesity-related conditions. It is to be hoped that the future will bring new drugs targeting specific obesity phenotypes that will allow clinicians to use etiology-specific, and therefore more effective, anti-obesity therapies.

A new class of drug for the management of type 2 diabetes: sodium glucose co-transporter inhibitors: 'glucuretics'

BACKGROUND

Type 2 diabetes is a common, chronic disease with a prevalence that is increasing at epidemic proportions. Management involves advice on lifestyle changes, oral anti-hyperglycaemic agents and/or insulin. The kidneys play a major role in the regulation of glucose, re-absorbing 99% of the plasma glucose filtered through the renal glomeruli tubules. The glucose transporter, SGLT2, which is found primarily in the S1 segment of the proximal renal tubule accounts for 90% of glucose re-absorption. Competitive inhibition of SGLT2 induces glucosuria in a dose dependent manner and appears to have beneficial effects on glucose regulation in individuals with type 2 diabetes. O-glucoside phlorozin is the model substance for SGLT2 inhibitors: various O-, C-, N- and S-glucosides with varying affinity and specificity have been synthesised.

AIMS

The aim of this review is to describe the background, the mechanism of action and the possible role for sodium glucose co-transporter inhibitors in the treatment of diabetes.

MATERIALS AND METHODS

Databases, including MEDLINE, COCHRANE, EMBASE and EBM reviews were searched for literature relating to sodium glucose transport inhibitors and improvements in glycaemic control in patients with diabetes.

RESULTS

The data suggest that sodium glucose transport inhibitors significantly improve glycaemic control by increasing glucosuria. Some studies described significant reductions in weight and improvement in blood pressure. The most common side effect was infection involving the urinary and genital tracts.

CONCLUSIONS

Sodium glucose co-transport inhibitors appear to be an effective line of treatment, well tolerated and could be a further drug class in the armamentarium available for the management of type 2 diabetes.

SGLT2 inhibitors: a promising new therapeutic option for treatment of type 2 diabetes mellitus

BACKGROUND

Hyperglycemia is an important pathogenic component in the development of microvascular and macrovascular complications in type 2 diabetes mellitus. Inhibition of renal tubular glucose reabsorption that leads to glycosuria has been proposed as a new mechanism to attain normoglycemia and thus prevent and diminish these complications. Sodium glucose cotransporter 2 (SGLT2) has a key role in reabsorption of glucose in kidney. Competitive inhibitors of SGLT2 have been discovered and a few of them have also been advanced in clinical trials for the treatment of diabetes.

OBJECTIVE

To discuss the therapeutic potential of SGLT2 inhibitors currently in clinical development.

KEY FINDINGS

A number of preclinical and clinical studies of SGLT2 inhibitors have demonstrated a good safety profile and beneficial effects in lowering plasma glucose levels, diminishing glucotoxicity, improving glycemic control and reducing weight in diabetes. Of all the SGLT2 inhibitors, dapagliflozin is a relatively advanced compound with regards to clinical development.

SUMMARY

SGLT2 inhibitors are emerging as a promising therapeutic option for the treatment of diabetes. Their unique mechanism of action offers them the potential to be used in combination with other oral anti-diabetic drugs as well as with insulin.

New possibility in the oral glucose lowering treatment of type 2 diabetes mellitus: sodium-glucose co-transporter-2 inhibitors

Sodium-glucose co-transporters (SGLTs) have a key role in the re-absorption of glucose in the kidneys. Therefore, inhibition of SGLTs may provide a novel therapeutic strategy for diabetes mellitus. SGLT2 inhibitors enhance renal glucose excretion by inhibiting renal glucose re-absorption and reduce plasma glucose level, as well as they decrease the body weight. Their action is insulin independent and they improve insulin resistance in diabetes mellitus. Numerous SGLT2 inhibitors have been developed and evaluated in clinical trials. Phase III trials are needed to assess the safety of SGLT2 inhibitors. Results suggest that the beneficial effects of SGLT2 inhibition might be achieved without the development of significant side effects. Orv. Hetil., 2012, 153, 695–701.

SGLT2 inhibition in diabetes mellitus: rationale and clinical prospects

This Review covers the rationale, physiological consequences and clinical application of pharmacological sodium-glucose cotransporter 2 (SGLT2) inhibition. In patients with type 2 diabetes mellitus, in whom renal glucose reabsorption might be upregulated, orally active, selective SGLT2 inhibitors improve glycaemic control to a therapeutically useful extent. Chronic administration of several SGLT2 inhibitors dose-dependently lowers HbA(1c) levels by 0.5-1.5% without causing hypoglycaemia. The unique mechanism of action of SGLT2 inhibitors-which does not hinge upon β-cell function or tissue insulin sensitivity-means that they can exert their antihyperglycaemic effects in combination with any other oral antidiabetic drug as well as insulin. Available phase III studies confirm a good tolerability profile. Weight loss owing to urinary calorie leakage may be less than expected, but the negative energy balance offers a valuable clinical benefit. Offloading of sodium can assist blood pressure control. The progressive loss of efficacy in patients with reduced glomerular function will have to be balanced against the possibility of renal protection. The safety issues of genitourinary infections and cancer risk requires careful, proactive monitoring and analysis of robust exposure data, particularly in elderly, frail patients and in patients with impaired kidney function and/or high cardiovascular/cancer risk, who represent an increasing fraction of the population with diabetes mellitus.

Structural selectivity of human SGLT inhibitors

Human Na(+)-D-glucose cotransporter (hSGLT) inhibitors constitute the newest class of diabetes drugs, blocking up to 50% of renal glucose reabsorption in vivo. These drugs have potential for widespread use in the diabetes epidemic, but how they work at a molecular level is poorly understood. Here, we use electrophysiological methods to assess how they block Na(+)-D-glucose cotransporter SGLT1 and SGLT2 expressed in human embryonic kidney 293T (HEK-293T) cells and compared them to the classic SGLT inhibitor phlorizin. Dapagliflozin [(1S)-1,5,5-anhydro-1-C-{4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl}-D-glucitol], two structural analogs, and the aglycones of phlorizin and dapagliflozin were investigated in detail. Dapagliflozin and fluoro-dapagliflozin [(1S)-1,5-anhydro-1-C-{4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl}-4-F-4-deoxy-D-glucitol] blocked glucose transport and glucose-coupled currents with ≈100-fold specificity for hSGLT2 (K(i) = 6 nM) over hSGLT1 (K(i) = 400 nM). As galactose is a poor substrate for SGLT2, it was surprising that galacto-dapagliflozin [(1S)-1,5-anhydro-1-C-{4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl}-D-galactitol] was a selective inhibitor of hSGLT2, but was less potent than dapagliflozin for both transporters (hSGLT2 K(i) = 25 nM, hSGLT1 K(i) = 25,000 nM). Phlorizin and galacto-dapagliflozin rapidly dissociated from SGLT2 [half-time off rate (t(1/2,Off)) ≈ 20-30 s], while dapagliflozin and fluoro-dapagliflozin dissociated from hSGLT2 at a rate 10-fold slower (t(1/2,Off) ≥ 180 s). Phlorizin was unable to exchange with dapagliflozin bound to hSGLT2. In contrast, dapagliflozin, fluoro-dapagliflozin, and galacto-dapagliflozin dissociated quickly from hSGLT1 (t(1/2,Off) = 1-2 s), and phlorizin readily exchanged with dapagliflozin bound to hSGLT1. The aglycones of phlorizin and dapagliflozin were poor inhibitors of both hSGLT2 and hSGLT1 with K(i) values > 100 μM. These results show that inhibitor binding to SGLTs is composed of two synergistic forces: sugar binding to the glucose site, which is not rigid, and so different sugars will change the orientation of the aglycone in the access vestibule; and the binding of the aglycone affects the binding affinity of the entire inhibitor. Therefore, the pharmacophore must include variations in both the structure of the sugar and the aglycone.

Development and potential role of type-2 sodium-glucose transporter inhibitors for management of type 2 diabetes

There is a recognized need for new treatment options for type 2 diabetes mellitus (T2DM). Recovery of glucose from the glomerular filtrate represents an important mechanism in maintaining glucose homeostasis and represents a novel target for the management of T2DM. Recovery of glucose from the glomerular filtrate is executed principally by the type 2 sodium-glucose cotransporter (SGLT2). Inhibition of SGLT2 promotes glucose excretion and normalizes glycemia in animal models. First reports of specifically designed SGLT2 inhibitors began to appear in the second half of the 1990s. Several candidate SGLT2 inhibitors are currently under development, with four in the later stages of clinical testing. The safety profile of SGLT2 inhibitors is expected to be good, as their target is a highly specific membrane transporter expressed almost exclusively within the renal tubules. One safety concern is that of glycosuria, which could predispose patients to increased urinary tract infections. So far the reported safety profile of SGLT2 inhibitors in clinical studies appears to confirm that the class is well tolerated. Where SGLT2 inhibitors will fit in the current cascade of treatments for T2DM has yet to be established. The expected favorable safety profile and insulin-independent mechanism of action appear to support their use in combination with other antidiabetic drugs. Promotion of glucose excretion introduces the opportunity to clear calories (80-90 g [300-400 calories] of glucose per day) in patients that are generally overweight, and is expected to work synergistically with weight reduction programs. Experience will most likely lead to better understanding of which patients are likely to respond best to SGLT2 inhibitors, and under what circumstances.

Pharmacodynamic model of sodium-glucose transporter 2 (SGLT2) inhibition: implications for quantitative translational pharmacology

Sodium-glucose co-transporter-2 (SGLT2) inhibitors are an emerging class of agents for use in the treatment of type 2 diabetes mellitus (T2DM). Inhibition of SGLT2 leads to improved glycemic control through increased urinary glucose excretion (UGE). In this study, a biologically based pharmacokinetic/pharmacodynamic (PK/PD) model of SGLT2 inhibitor-mediated UGE was developed. The derived model was used to characterize the acute PK/PD relationship of the SGLT2 inhibitor, dapagliflozin, in rats. The quantitative translational pharmacology of dapagliflozin was examined through both prospective simulation and direct modeling of mean literature data obtained for dapagliflozin in healthy subjects. Prospective simulations provided time courses of UGE that were of consistent shape to clinical observations, but were modestly biased toward under prediction. Direct modeling provided an improved characterization of the data and precise parameter estimates which were reasonably consistent with those predicted from preclinical data. Overall, these results indicate that the acute clinical pharmacology of SGLT2 inhibitors in healthy subjects can be reasonably well predicted from preclinical data through rational accounting of species differences in pharmacokinetics, physiology, and SGLT2 pharmacology. Because these data can be generated at the earliest stages of drug discovery, the proposed model is useful in the design and development of novel SGLT2 inhibitors. In addition, this model is expected to serve as a useful foundation for future efforts to understand and predict the effects of SGLT2 inhibition under chronic administration and in other patient populations.

SGLT2 inhibitors: a new emerging therapeutic class in the treatment of type 2 diabetes mellitus

The incidence of type 2 diabetes mellitus is increasing worldwide. The existing therapeutic classes of antidiabetic drugs are not adequately effective in maintaining long-term glycemic control in most patients, even when used in combination. One emerging novel therapeutic class of antidiabetic drugs is sodium glucose cotransporter 2 (SGLT2) inhibitors. SGLT2 accounts for 90% of the glucose reabsorption in the kidney. The SGLT2 inhibitors increase urinary excretion of glucose and lower plasma glucose levels in an insulin-independent manner. Dapagliflozin, the most prominent molecule in this class, is currently in a phase III clinical trial. Other members of this class (eg, sergliflozin, remogliflozin) are also in different phases of clinical trials. This class of novel agents can effectively control blood sugar level without producing weight gain or hypoglycemia. Results of ongoing phase III clinical trials are crucial to determine whether the risk-benefit ratio will allow approval of this new class of drugs for the management of type 2 diabetes mellitus.

Sodium-glucose transport: role in diabetes mellitus and potential clinical implications

PURPOSE OF REVIEW

Current options for glycemic control are less than optimal in terms of efficacy and to reduce complications in the diabetic population. Selective inhibition of SGLT2 in the proximal tubule increases urinary glucose excretion thereby reducing plasma glucose levels, which may present a novel therapeutic approach.

RECENT FINDINGS

SGLT2 inhibitors enhance glucose excretion and improve glycemic control in patients with type 2 diabetes in the absence of clinically relevant hypoglycemia or sustained changes in volume status or glomerular filtration rate. This is associated with lowering of body weight and may reduce systolic blood pressure. The increased glucosuria appears to increase the risk of genital infections but may not increase the risk of urinary tract infections.

SUMMARY

The ability of SGLT2 inhibitors to reduce plasma glucose without inducing increased insulin secretion, clinically relevant hypoglycemia, or weight gain constitutes a major advance. The ability to increase glucose excretion provides a powerful means to treat caloric excess conditions. Important questions remain to be resolved and more clinical research is needed on the long-term effects of SGLT2 inhibition. Potential extrarenal effects need to be explored in order to determine the safety of these compounds. It also remains to be determined whether these drugs lower the toxicity of glucose directly on renal cells, independent of hyperglycemia, which may slow or prevent the progressive nature of diabetic nephropathy.

SGLT2 inhibition--a novel strategy for diabetes treatment

Inhibiting sodium-glucose co-transporters (SGLTs), which have a key role in the reabsorption of glucose in the kidney, has been proposed as a novel therapeutic strategy for diabetes. Genetic mutations in the kidney-specific SGLT2 isoform that result in benign renal glycosuria, as well as preclinical and clinical studies with SGLT2 inhibitors in type 2 diabetes, support the potential of this approach. These investigations indicate that elevating renal glucose excretion by suppressing SGLT2 can reduce plasma glucose levels, as well as decrease weight. Although data from ongoing Phase III trials of these agents are needed to more fully assess safety, results suggest that the beneficial effects of SGLT2 inhibition might be achieved without exerting significant side effects--an advantage over many current diabetes medications. This article discusses the role of SGLT2 in glucose homeostasis and the evidence available so far on the therapeutic potential of blocking these transporters in the treatment of diabetes.