Effect of dapagliflozin in patients with type 2 diabetes who have inadequate glycaemic control with glimepiride: a randomized, 24-week, double-blind, placebo-controlled trial

Patient considerations in the management of type 2 diabetes - critical appraisal of dapagliflozin

Type 2 diabetes affects more than 350 million people worldwide, and its prevalence is increasing. Many patients with diabetes do not achieve and/or maintain glycemic targets, despite therapy implementation and escalation. Multiple therapeutic classes of agents are available for the treatment of type 2 diabetes, and the armamentarium has expanded significantly in the past decade. Selective sodium glucose co-transporter 2 inhibitors, including dapagliflozin, represent the latest development in pharmacologic treatment options for type 2 diabetes. This class has a unique mechanism of action, working by increasing glucose excretion in the urine. The insulin-independent mechanism results in decreased serum glucose, without hypoglycemia or weight gain. Dapagliflozin is a once-daily oral therapy. Expanding therapy options for a complex patient population is critical, and dapagliflozin has a distinct niche that can be a viable option for select patients with diabetes.

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.

Dapagliflozin as monotherapy in drug-naive Asian patients with type 2 diabetes mellitus: a randomized, blinded, prospective phase III study

OBJECTIVE

Dapagliflozin is a highly selective, orally active inhibitor of renal sodium-glucose cotransporter 2 that reduces hyperglycemia by increasing urinary glucose excretion. The goal of this study was to evaluate dapagliflozin as monotherapy in drug-naive Asian patients with type 2 diabetes whose disease was inadequately controlled with diet and exercise.

METHODS

In this Phase III, multicenter, parallel-group, double-blind study, drug-naive patients with glycosylated hemoglobin (HbA1c) levels ≥7.0% to ≤10.5% (≥53-≤91 mmol/mol) were randomized (by using an interactive voice response system) to receive placebo (n = 132), dapagliflozin 5 mg (n = 128), or dapagliflozin 10 mg (n = 133). The primary end point was mean change from baseline in HbA1c level at week 24 (last-observation-carried-forward). Secondary end points included changes in fasting plasma glucose, 2-hour postprandial glucose, body weight, and other glycemic parameters.

RESULTS

Baseline characteristics were balanced across groups. Most patients (89%) were Chinese, median disease duration was 0.2 year, and mean HbA1c level was 8.26%. Most patients (87%) completed the study. At week 24, mean reductions in HbA1c were -0.29% for placebo versus -1.04% and -1.11% for dapagliflozin 5 and 10 mg, respectively (P < 0.0001 for both doses). Changes in fasting plasma glucose were 2.5, -25.1, and -31.6 mg/dL (0.14, -1.39, and -1.75 mmol/L) for placebo, dapagliflozin 5 mg, and dapagliflozin 10 mg. Changes in 2-hour postprandial glucose were 1.1, -46.8, and -54.9 mg/dL (0.06, -2.60, and -3.05 mmol/L). Reductions in body weight were -0.27, -1.64, and -2.25 kg. Proportions of patients achieving HbA1c levels <7.0% (53 mmol/mol) were 21.3%, 42.6%, and 49.8%. Adverse events (AEs) occurred in 63.6%, 61.7%, and 60.9% of patients, and serious AEs occurred in 1.5%, 3.9%, and 3.0% of patients. No deaths occurred. Hypoglycemia was uncommon (1.5%, 0.8%, and 0.8%); no hypoglycemic event led to discontinuation. Genital infections occurred in 0.8%, 3.1%, and 4.5% of patients and urinary tract infections in 3.0%, 3.9%, and 5.3% of patients. No AEs of renal infection or pyelonephritis were reported. No changes in renal function or AEs of renal failure occurred.

CONCLUSIONS

Compared with placebo, dapagliflozin 5 and 10 mg demonstrated clinically and statistically significant improvements in HbA1c levels after 24 weeks of treatment. Dose-dependent, statistically significant reductions in fasting plasma glucose, postprandial glucose, and weight were also observed for both doses compared with placebo. AEs and serious AEs were balanced across groups, with low rates of hypoglycemia and no increase in renal events. Genital infections and urinary tract infections were more common with dapagliflozin. Dapagliflozin as monotherapy in these drug-naive Asian patients was well tolerated, significantly improving glycemic control with the additional benefit of weight loss.

Sodium glucose co-transport 2 inhibitors in the treatment of type 2 diabetes mellitus: a meta-analysis of randomized double-blind controlled trials

BACKGROUND

The discovery of sodium-glucose co-transporter 2 (SGLT2) inhibitors, with a novel mechanism independent of insulin secretion or sensitization, bring about a new therapeutic approach to the management of type 2 diabetes mellitus. The aim of this meta-analysis was to evaluate the safety and efficacy of SGLT2 inhibitors at different doses in randomized double blind clinical trials.

METHODS

This meta-analysis was conducted by including randomized double-blind controlled trials of SGLT2 inhibitors in patients with type 2 diabetes irrespective of their antidiabetic drug exposure history but with an inadequate glycemic control. All the effect sizes were computed using the random effects model. Standardized mean differences (SMDs) and odds ratios (OR) were computed for continuous and dichotomous variables, respectively. Additional analyses like sensitivity analysis, subgroup analysis and meta-regression were also performed.

RESULTS

The pooled analyses demonstrated a significant reduction in mean changes in Hemoglobin A1c (HbA1c) (SMD = -0.78%, 95% CI, -0.87 to -0.69), fasting plasma glucose (FPG) (SMD = -0.70 mg/dl, 95% CI, -0.79 to -0.61), body weight (overall SMD = -0.59 kg, 95% CI, -0.65 to -0.52) and blood pressure from baseline with SGLT2 inhibitors based therapy. Consistently a significant number of patients treated with SGLT2 inhibitors achieved HbA1c < 7% (OR = 2.09, 95% CI, 1.77 to 2.46). SGLT2 inhibitors based therapy was associated with adverse events like genital and urinary tract infections.

CONCLUSION

All studied doses of SGLT2 inhibitors, either as monotherapy or in combination with other antidiabetic agents, consistently improved glycemic control in patients with type 2 diabetes. However, a small percentage of patients suffer from genital and urinary tract infections.

Sodium Glucose Co-transporter Type 2 (SGLT2) Inhibitors: Targeting the Kidney to Improve Glycemic Control in Diabetes Mellitus

Although hyperglycemia is a key therapeutic focus in the management of patients with type 2 diabetes mellitus (T2DM), many patients experience sub-optimal glycemic control. Current glucose-lowering agents involve the targeting of various body organs. Sodium glucose co-transporter type 2 (SGLT2) inhibitors target the kidney, reduce renal glucose reabsorption, and increase urinary glucose elimination, thus lowering glucose blood levels. This review examines some of the key efficacy and safety data from clinical trials of the main SGLT2 inhibitors approved or currently in development, and provides a rationale for the use of SGLT2 inhibitors in the treatment of T2DM.

Efficacy and safety of canagliflozin in patients with type 2 diabetes mellitus inadequately controlled with metformin and sulphonylurea: a randomised trial

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor developed for the treatment of type 2 diabetes mellitus (T2DM). This randomised, double-blind, placebo-controlled, Phase 3 study evaluated the efficacy and safety of canagliflozin as an add-on to metformin plus sulphonylurea in patients with T2DM.

METHODS

Patients (N = 469) received canagliflozin 100 or 300 mg or placebo once daily during a 26-week core period and a 26-week extension. Prespecified primary end-point was change in HbA1c at 26 weeks. Secondary end-points included change in HbA1c at week 52 as well as proportion of patients achieving HbA1c < 7.0%, change in fasting plasma glucose (FPG) and systolic blood pressure, and per cent change in body weight, high-density lipoprotein cholesterol, and triglycerides (weeks 26 and 52).

RESULTS

HbA1c was significantly reduced with canagliflozin 100 and 300 mg vs. placebo at week 26 (-0.85%, -1.06%, and -0.13%; p < 0.001); these reductions were maintained at week 52 (-0.74%, -0.96%, and 0.01%). Both canagliflozin doses reduced FPG and body weight vs. placebo at week 26 (p < 0.001) and week 52. Overall adverse event (AE) rates were similar across groups over 52 weeks, with higher rates of genital mycotic infections and osmotic diuresis-related AEs seen with canagliflozin vs. placebo; these led to few discontinuations. Increased incidence of documented, but not severe, hypoglycaemia episodes was seen with canagliflozin vs. placebo.

CONCLUSIONS

Canagliflozin improved glycaemic control, reduced body weight, and was generally well tolerated in T2DM patients on metformin plus sulphonylurea over 52 weeks.

SGLT-2 inhibitors and their potential in the treatment of diabetes

Diabetes remains a burgeoning global problem, necessitating ongoing efforts on the part of pharmaceutical and device manufacturers, patients, and society to curb the frightening trends in morbidity and mortality attributable to the malady. Since 1835 when phlorizin was discovered, sodium glucose co-transporter 2 (SGLT-2) inhibitors have rested tantalizingly on the horizon, promising a more physiological approach to glucose control. These agents lower glucose by enhancing its excretion by blocking reabsorption in the renal tubules, thus eliminating glucose from the body along with the molecules' attendant effects on caloric balance, plasma osmolality, and lipids. Consequently, SGLT-2 inhibitors improve glucose control to an extent comparable to other hypoglycemic agents while simultaneously reducing body weight, blood pressure, and cholesterol - an admirable portfolio. One agent, canagliflozin, has recently been approved by the US Food and Drug Administration (FDA) and two other agents have progressed through Phase III trials, including dapagliflozin and empagliflozin. Collectively, when used as monotherapy, these agents have demonstrated reductions in hemoglobin A1c (HbA1c), body weight, and blood pressure of -0.34% to -1.03%, -2.0 to -3.4 kg, and -1.7 to -6.4 mmHg/-0.3 to -2.6 mmHg (systolic blood pressure/diastolic blood pressure), respectively. SGLT-2 inhibitors have been well tolerated, with hypoglycemia (0.9% to 4.3%) occurring infrequently in clinical trials. Safety signals related to breast and bladder cancer have arisen with dapagliflozin, though these are unsubstantiated and likely ascribed to the presence of preexisting cancer. As these agents emerge, clinicians should embrace the addition to the formulary for treating type 2 diabetes, but must also weight the risk-benefit of this new class in deciding which patient types are most likely to benefit from their novel mechanism of action.

SGLT inhibitors in management of diabetes

The two main sodium-glucose cotransporters (SGLTs), SGLT1 and SGLT2, provide new therapeutic targets to reduce hyperglycaemia in patients with diabetes. SGLT1 enables the small intestine to absorb glucose and contributes to the reabsorption of glucose filtered by the kidney. SGLT2 is responsible for reabsorption of most of the glucose filtered by the kidney. Inhibitors with varying specificities for these transporters (eg, dapagliflozin, canagliflozin, and empagliflozin) can slow the rate of intestinal glucose absorption and increase the renal elimination of glucose into the urine. Results of randomised clinical trials have shown the blood glucose-lowering efficacy of SGLT inhibitors in type 2 diabetes when administered as monotherapy or in addition to other glucose-lowering therapies including insulin. Increased renal glucose elimination also assists weight loss and could help to reduce blood pressure. Effective SGLT2 inhibition needs adequate glomerular filtration and might increase risk of urinary tract and genital infection, and excessive inhibition of SGLT1 can cause gastro-intestinal symptoms. However, the insulin-independent mechanism of action of SGLT inhibitors seems to offer durable glucose-lowering efficacy with low risk of clinically significant hypoglycaemia at any stage in the natural history of type 2 diabetes. SGLT inhibition might also be considered in conjunction with insulin therapy in type 1 diabetes.

Long-term study of patients with type 2 diabetes and moderate renal impairment shows that dapagliflozin reduces weight and blood pressure but does not improve glycemic control

In patients with diabetes, glycemic improvement by sodium-glucose cotransporter-2 inhibition depends on the kidney's ability to filter glucose. Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, reduces hyperglycemia in patients with diabetes and normal or mildly impaired renal function. In this randomized, double-blind, placebo-controlled study we assessed daily treatment with dapagliflozin in 252 patients with inadequately controlled type 2 diabetes and moderate renal impairment. The primary endpoint, the mean change in HbA1c, was not statistically different from placebo after 24 weeks (-0.41% and -0.44% for 5- and 10-mg doses, respectively, and -0.32% for placebo). The mean weight change from baseline was -1.54 and -1.89 kg for the 5- and 10-mg doses, respectively, and +0.21 kg for placebo. The mean systolic and diastolic blood pressure decreased in the dapagliflozin groups compared to placebo. Through 104 weeks, 13 patients receiving dapagliflozin and no patients receiving placebo experienced bone fracture. At 1 week, the mean serum creatinine increased with dapagliflozin 5 mg (+0.13 mg/dl) and 10 mg (+0.18 mg/dl) and did not change further after 104 weeks. Mean serum electrolytes did not change in any group, and there were fewer episodes of hyperkalemia with dapagliflozin than placebo. Thus, in patients with moderate renal impairment, dapagliflozin did not improve glycemic control, but reduced weight and blood pressure.

Dapagliflozin (Forxiga) for type 2 diabetes?

In the UK, diabetes mellitus affects around 3 million people, of whom over 90% have type 2 diabetes. Aims of treatment include minimising long-term complications (e.g. cardiovascular disease, blindness, chronic kidney disease, premature mortality) and avoiding unwanted effects of treatment (e.g. severe hypoglycaemia, weight gain). Management of diabetes includes patient support and education; addressing symptoms; lifestyle modification; targeting associated risk factors for cardiovascular disease; and surveillance for, and management of, complications including treatment-related hypoglycaemia. Dapagliflozin (Forxiga) belongs to a new class of oral glucose-lowering drugs that inhibit renal glucose reabsorption and promote glycosuria. It is licensed in the UK in adults with type 2 diabetes as monotherapy when diet and exercise alone do not provide adequate glycaemic control and who are unable to tolerate metformin; or, as add-on therapy, with other glucose-lowering agents including insulin, when these, with diet and exercise, do not provide adequate glycaemic control. The company's advertising materials claim that dapagliflozin provides a "novel method of controlling excess glucose" with "secondary benefit of weight loss". Here, we review the evidence for the use of dapagliflozin in the management of type 2 diabetes mellitus.

Canagliflozin compared with sitagliptin for patients with type 2 diabetes who do not have adequate glycemic control with metformin plus sulfonylurea: a 52-week randomized trial

OBJECTIVE

To evaluate the efficacy and safety of canagliflozin, a sodium glucose cotransporter 2 inhibitor, compared with sitagliptin in subjects with type 2 diabetes inadequately controlled with metformin plus sulfonylurea.

RESEARCH DESIGN AND METHODS

In this 52-week, randomized, double-blind, active-controlled, phase 3 study, subjects using stable metformin plus sulfonylurea (N = 755) received canagliflozin 300 mg or sitagliptin 100 mg daily. Primary end point was change from baseline in A1C at 52 weeks. Secondary end points included change in fasting plasma glucose (FPG) and systolic blood pressure (BP), and percent change in body weight, triglycerides, and HDL cholesterol. Safety was assessed based on adverse event (AE) reports.

RESULTS

At 52 weeks, canagliflozin 300 mg demonstrated noninferiority and, in a subsequent assessment, showed superiority to sitagliptin 100 mg in reducing A1C (-1.03% [-11.3 mmol/mol] and -0.66% [-7.2 mmol/mol], respectively; least squares mean difference between groups, -0.37% [95% CI, -0.50 to -0.25] or -4.0 mmol/mol [-5.5 to -2.7]). Greater reductions in FPG, body weight, and systolic BP were observed with canagliflozin versus sitagliptin (P < 0.001). Overall AE rates were similar with canagliflozin (76.7%) and sitagliptin (77.5%); incidence of serious AEs and AE-related discontinuations was low for both groups. Higher incidences of genital mycotic infections and osmotic diuresis-related AEs were observed with canagliflozin, which led to one discontinuation. Hypoglycemia rates were similar in both groups.

CONCLUSIONS

Findings suggest that canagliflozin may be a new therapeutic tool providing better improvement in glycemic control and body weight reduction than sitagliptin, but with increased genital infections in subjects with type 2 diabetes using metformin plus sulfonylurea.

Urinary tract infections in patients with diabetes treated with dapagliflozin

AIMS

Urinary tract infection is common in patients with type 2 diabetes. Possible causative factors include glucosuria, which is a result of treatment with sodium glucose cotransporter 2 (SGLT2) inhibitors. Dapagliflozin is an investigative SGLT2 inhibitor with demonstrated glycemic benefits in patients with diabetes. Data from dapagliflozin multi-trial safety data were analyzed to clarify the association between glucosuria and urinary tract infection.

METHODS

Safety data from 12 randomized, placebo-controlled trials were pooled to evaluate the relationship between glucosuria and urinary tract infection in patients with inadequately controlled diabetes (HbA1c >6.5%-12%). Patients were treated with dapagliflozin (2.5, 5, or 10mg) or placebo once daily, either as monotherapy or add-on to metformin, insulin, sulfonylurea, or thiazolidinedione for 12-24weeks. The incidence of clinical diagnoses and events suggestive of urinary tract infection were quantified.

RESULTS

This analysis included 3152 patients who received once-daily dapagliflozin (2.5mg [n=814], 5mg [n=1145], or 10mg [n=1193]) as monotherapy or add-on treatment, and 1393 placebo-treated patients. For dapagliflozin 2.5mg, 5mg, 10mg, and placebo, diagnosed infections were reported in 3.6%, 5.7%, 4.3%, and 3.7%, respectively. Urinary glucose levels, but not the incidence of urinary tract infection, increased progressively with dapagliflozin dosage. Most identified infections were those considered typical for patients with diabetes. Discontinuations due to urinary tract infection were rare: 8 (0.3%) dapagliflozin-treated patients and 1 (0.1%) placebo-treated patient. Most diagnosed infections were mild to moderate and responded to standard antimicrobial treatment.

CONCLUSIONS

Treatment of type 2 diabetes with once-daily dapagliflozin 5 or 10mg is accompanied by a slightly increased risk of urinary tract infection. Infections were generally mild to moderate and clinically manageable. This analysis did not demonstrate a definitive dose relationship between glucosuria and urinary tract infection.

Vulvovaginitis and balanitis in patients with diabetes treated with dapagliflozin

BACKGROUND

Vulvovaginitis, balanitis, and related genital infections are common in patients with type 2 diabetes. Glucosuria, which is an outcome of treatment with sodium glucose cotransporter 2 (SGLT2) inhibitors, is among the possible causes. Dapagliflozin, an SGLT2 inhibitor with demonstrated glycemic benefits in patients with diabetes, has been studied across a broad spectrum of patients. Analysis of multi-trial safety data may better define the relationship between glucosuria and genital infection.

METHODS

Safety data were pooled from 12 randomized, placebo-controlled Phase 2b/3 trials to analyze the association of glucosuria with genital infection in patients with suboptimally controlled diabetes (HbA1c >6.5%-12%). Patients were randomized to receive dapagliflozin (2.5mg, 5mg, or 10mg) or placebo once daily, either as monotherapy or add-on to metformin, insulin, sulfonylurea, or thiazolidinedione for 12-24weeks. The incidence of clinical diagnoses and of events suggestive of genital infection was evaluated.

RESULTS

The pooled safety data included 4545 patients: 3152 who received once-daily dapagliflozin (2.5mg [n=814], 5mg [n=1145], or 10mg [n=1193]) as monotherapy or add-on treatment, and 1393 placebo-treated patients. For dapagliflozin 2.5mg, 5mg, 10mg, and placebo, diagnosed infections were reported in 4.1%, 5.7%, 4.8%, and 0.9%, respectively. Most infections were mild or moderate and responded to standard antimicrobial treatment. Discontinuation due to these events was rare. No clear dose-response relationship between dapagliflozin and genital infection was demonstrated.

CONCLUSIONS

Treatment with dapagliflozin 2.5mg, 5mg, or 10mg once daily is accompanied by an increased risk of vulvovaginitis or balanitis, related to the induction of glucosuria. Events were generally mild to moderate, clinically manageable, and rarely led to discontinuation of treatment.

Effects of dapagliflozin on cardiovascular risk factors

People with diabetes are more likely to develop a cardiovascular (CV) disease compared with those without diabetes. Although effective glycemic control has been the focus of the management of type 2 diabetes mellitus (T2DM), it is also important to control other CV risk factors to improve outcomes in these patients. Dapagliflozin, a sodium-glucose co-transporter 2 inhibitor, lowers glucose levels in patients with T2DM by increasing urinary glucose excretion. Dapagliflozin therapy has been shown to impact a number of CV risk factors. Dapagliflozin improved glycemia with a low intrinsic propensity to cause hypoglycemia. Caloric loss associated with dapagliflozin-induced glucosuria also led to body weight reduction. Small changes from baseline in mean lipid parameters and reductions in serum uric acid levels were observed in patients taking dapagliflozin. Blood pressure reductions were also noted, consistent with modest drug-induced diuresis and weight loss. Furthermore, a lower rate of cardiac events was seen in patients taking dapagliflozin compared with those taking comparators in a meta-analysis of clinical trials on dapagliflozin. Overall, dapagliflozin has shown beneficial effects on CV risk factors in patients with T2DM. Further studies are underway to evaluate the effect of dapagliflozin on CV outcomes.

Review of insulin-dependent and insulin-independent agents for treating patients with type 2 diabetes mellitus and potential role for sodium-glucose co-transporter 2 inhibitors

Diabetes, especially type 2 diabetes mellitus (T2DM), continues to be a global health care problem. Although the beneficial effects of glycemic control are well established, in the United States, > 40% of adults with diabetes fail to achieve target glycated hemoglobin levels. Antidiabetic drug classes vary with respect to their mechanisms of action, glucose-lowering potential, and safety and tolerability profiles. Antidiabetic drug classes include some agents that depend on the presence or action of insulin for their therapeutic effect. As the disease state of T2DM progresses, patient pancreatic β-cell function declines, and therapies that stimulate insulin secretion or improve insulin sensitivity become less effective for this population. Therefore, the development of additional antidiabetic agents with novel mechanisms of action that can be used alone or in combination with currently approved medications may help patients achieve glycemic control. Agents that have comparable glucose-lowering capabilities but different mechanisms of action may fill treatment gaps or meet the needs of patient subpopulations. For example, inhibitors of sodium-glucose co-transporter 2 (SGLT2) represent an emerging class of glucose-lowering agents. The SGLT2 inhibitors reduce glucose reabsorption by the kidney, leading to increased urinary glucose excretion and caloric loss. In clinical trials, these agents have been shown to improve glycemic control and to reduce body weight in patients with T2DM. Additionally, SGLT2 inhibitors pose a low risk for hypoglycemia and are generally well tolerated; however, their use has been associated with an increase in the frequency of genital infections and, in some studies, urinary tract infections. Sodium-glucose co-transporter 2 inhibitors may provide an alternative or an addition to existing therapies for the treatment of patients with T2DM.

New and Future Medications for the Treatment of Type 2 Diabetes Mellitus

With almost 30 million individuals predicted to be diagnosed by the year 2025, type 2 diabetes mellitus (T2DM) has become one of the most prevalent diseases in the United States. Because of the progressive dysfunction of the pancreatic β-cells and increasing insulin resistance over time, the need for treatments with different mechanisms or addition of medications to a regimen is becoming commonplace. Because of this, developing new medications to treat T2DM has been the focus of a lot of recent research and drug development. Molecular substrates such as glucagon-like peptide-1 (GLP-1), dipeptidyl peptidase-4 (DPP-4), and the sodium glucose transporter-2 (SGLT2) have all become new therapeutic targets. GLP-1 agonists and DPP-4 inhibitors are 2 of the newest classes of Food and Drug Administration–approved medications for diabetes. By increasing GLP-1 to supraphysiologic levels (GLP-1 agonists) and delaying endogenous GLP-1 degradation (DPP-4 inhibitors), these drugs increase insulin secretion and decrease glucagon production. SGLT2 inhibitors, the newest antihyperglycemic class, promote glycosuria by inhibiting sodium and glucose reabsorption in the proximal tubule of the renal nephron. Other novel agents for the treatment of diabetes include the use of the dopamine agonist bromocriptine, the cholesterol medication colesevelam, and a new form of inhaled insulin.

Efficacy and safety of canagliflozin treatment in older subjects with type 2 diabetes mellitus: a randomized trial

INTRODUCTION

Canagliflozin is a sodium glucose co-transporter 2 inhibitor developed for the treatment of patients with type 2 diabetes mellitus (T2DM). Our randomized, double-blind, placebo-controlled, phase 3 study (www.clinicaltrials.gov: NCT01106651) evaluated the efficacy and safety of canagliflozin therapy in older subjects (aged 55-80 years) with T2DM inadequately controlled on their current regimen of blood glucose-lowering agents (any approved oral or injectable treatment).

METHODS

Subjects (N = 716) aged 55 to 80 years (mean, 63.6 years) with glycated hemoglobin (HbA1c) levels ≥ 7.0% to ≤ 10.0% were randomized. Seven hundred fourteen received canagliflozin 100 mg or 300 mg or placebo (1:1:1) daily. The prespecified primary endpoint was change from baseline in HbA1c level at week 26. Prespecified secondary endpoints included proportion of subjects achieving HbA1c levels < 7.0%, change from baseline in fasting plasma glucose (FPG) level and systolic blood pressure (BP), and percent change from baseline in body weight, triglyceride levels, and high-density lipoprotein cholesterol (HDL-C) level. Adverse events (AEs) were reported throughout the study.

RESULTS

At week 26, treatment with canagliflozin 100 mg and 300 mg significantly reduced HbA1c levels compared with placebo (-0.60%, -0.73%, -0.03%, respectively; P < 0.001); more subjects achieved HbA1c levels < 7.0% with both canagliflozin doses compared with placebo (P < 0.001). Both canagliflozin doses significantly reduced body weight, FPG level, and systolic BP, and increased HDL-C level compared with placebo (P < 0.001); low-density lipoprotein cholesterol level was increased with both canagliflozin doses compared with placebo. The overall AE incidence was slightly higher with canagliflozin 300 mg than with canagliflozin 100 mg or placebo (78.0%, 72.2%, 73.4%, respectively). Serious AE and AE-related discontinuation rates were low across groups. Both canagliflozin doses were associated with higher rates than placebo of genital mycotic infections, urinary tract infections, and osmotic diuresis-related AEs (ie, pollakiuria, polyuria). Documented hypoglycemia rates were modestly higher with both canagliflozin doses compared with placebo.

CONCLUSION

Canagliflozin improved glycemic control, reduced body weight and systolic BP, and was generally well tolerated in older subjects with T2DM who were on background therapy with a variety of blood glucose-lowering agents.

Sodium-glucose cotransporter inhibition: therapeutic potential for the treatment of type 2 diabetes mellitus

Results from randomized controlled trials have demonstrated that the risk of microvascular complications can be reduced by intensive glycaemic control in patients with type 2 diabetes mellitus (T2DM). However, only about half of patients with diagnosed diabetes achieve recommended glycaemic goals. New therapies with complementary mechanisms of action that are independent of insulin secretion or action may provide additional therapeutic options to enable patients to achieve glycaemic control. The kidney plays an important role in glucose homeostasis, primarily by the reabsorption of filtered glucose. The sodium-glucose cotransporter 2 (SGLT2), located in the proximal convoluted tubule, is responsible for the majority of glucose reabsorption by the kidney. SGLT2 inhibitors offer a novel approach to treat T2DM and reduce hyperglycaemia by increasing urinary excretion of glucose. Dapagliflozin, an SGLT2 inhibitor recently approved in Europe for the treatment of T2DM, improves glycaemic control in patients with T2DM when used as monotherapy or when added to other diabetes medications, such as metformin, sulfonylureas, pioglitazone, and insulin. As a class, SGLT2 inhibitors are well tolerated and have a low propensity to cause hypoglycaemia. An increase in signs, symptoms, and other events suggestive of genital and, in some studies, urinary tract infections has been reported with SGLT2 inhibitors. Results from ongoing and future clinical trials will help define the role for this new class of investigational compounds, with its unique mechanism of action, as a treatment option for reducing hyperglycaemia in patients with T2DM.

Dapagliflozin for the treatment of type 2 diabetes

INTRODUCTION

Despite the availability of many antihypreglycemic agents, many patients with type 2 diabetes (T2DM) fail to achieve the glycemic treatment goal, primarily due to progressive beta-cell dysfunction, and increased risk of hypoglycemia.

AREAS COVERED

The aim of the present article is to review the efficacy and safety of dapagliflozin , a novel antihyperglycemic drug that lowers the plasma glucose concentration by the inhibition of renal sodium-glucose cotransport, in lowering the plasma glucose concentration and the HbA1c in T2DM patents. This review summarizes the published data about the mechanism of action and clinical efficacy of dapagliflozin in lowering the HbA1c in patients with T2DM. It also discusses additional non-glycemic benefits of dapagliflozin and the safety profile of the drug.

EXPERT OPINION

Dapagliflozin is effective in lowering the plasma glucose concentration in patients with T2DM with a good safety profile. Because of its unique mechanism of action, dapagliflozin can be utilized in combination with all other antihyperglycemic agents and at all stages of the disease.

The clinical efficacy and safety of sodium glucose cotransporter-2 inhibitors in adults with type 2 diabetes mellitus

The use of currently available antihyperglycemic agents can be limited by contraindications; cost; renal and hepatic dosage adjustments; dosing schedules; and adverse effects such as gastrointestinal upset, weight gain, and hypoglycemia. These limitations have led the pharmaceutical industry to identify and pursue alternative therapies. Sodium glucose cotransporter-2 (SGLT-2) inhibitors belong to a new class of diabetes drugs and have a novel mechanism of action. These agents are unique in that they increase glucose excretion, independent of insulin secretion, by inhibiting the renal reabsorption of glucose, inducing glycosuria. To summarize the current evidence for SGLT-2 inhibitor therapy, we reviewed abstracts and published data from human trials evaluating the efficacy and safety of dapagliflozin, canagliflozin, and empagliflozin through February 2013. Data from these trials suggest that SGLT-2 inhibitors are able to lower hemoglobin A1c and fasting blood glucose when used as either monotherapy or combination therapy. Cardiometabolic benefits included a reduction in systolic blood pressure, reduction in triglycerides, and weight loss of up to 3 kg. Common and serious adverse effects including infections, cancer, and pollakiuria were identified and reviewed. Although these agents have generally demonstrated efficacy, the adverse effects associated with dapagliflozin have caused a delay in its regulatory approval. Continued research in this area will determine the risk:benefit ratio of SGLT-2 inhibitor therapy.

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.

Efficacy and safety of canagliflozin in subjects with type 2 diabetes and chronic kidney disease

AIMS

Canagliflozin is a sodium glucose co-transporter 2 inhibitor in development for treatment of type 2 diabetes mellitus (T2DM). This study evaluated the efficacy and safety of canagliflozin in subjects with T2DM and stage 3 chronic kidney disease [CKD; estimated glomerular filtration rate (eGFR) ≥30 and <50 ml/min/1.73 m(2)].

METHODS

In this randomized, double-blind, placebo-controlled, phase 3 trial, subjects (N = 269) received canagliflozin 100 or 300 mg or placebo daily. The primary efficacy endpoint was change from baseline in HbA1c at week 26. Prespecified secondary endpoints were change in fasting plasma glucose (FPG) and proportion of subjects reaching HbA1c <7.0%. Safety was assessed based on adverse event (AE) reports; renal safety parameters (e.g. eGFR, blood urea nitrogen and albumin/creatinine ratio) were also evaluated.

RESULTS

Both canagliflozin 100 and 300 mg reduced HbA1c from baseline compared with placebo at week 26 (-0.33, -0.44 and -0.03%; p < 0.05). Numerical reductions in FPG and higher proportions of subjects reaching HbA1c < 7.0% were observed with canagliflozin 100 and 300 mg versus placebo (27.3, 32.6 and 17.2%). Overall AE rates were similar for canagliflozin 100 and 300 mg and placebo (78.9, 74.2 and 74.4%). Slightly higher rates of urinary tract infections and AEs related to osmotic diuresis and reduced intravascular volume were observed with canagliflozin 300 mg compared with other groups. Transient changes in renal function parameters that trended towards baseline over 26 weeks were observed with canagliflozin.

CONCLUSION

Canagliflozin improved glycaemic control and was generally well tolerated in subjects with T2DM and Stage 3 CKD.

The potential of sodium glucose cotransporter 2 (SGLT2) inhibitors to reduce cardiovascular risk in patients with type 2 diabetes (T2DM)

Type 2 diabetes mellitus (T2DM) significantly increases morbidity and mortality from cardiovascular disease (CVD). Treatments for patients with T2DM have the potential to reduce cardiovascular (CV) risk. This review focuses on the potential of a new class of antidiabetic agents, the sodium glucose cotransporter 2 (SGLT2) inhibitors, to reduce CV risk in patients with T2DM through reductions in hyperglycemia, blood pressure (BP), and body weight. The results of clinical trials of SGLT2 inhibitors are summarized and discussed.

Efficacy and safety of dapagliflozin as a monotherapy for type 2 diabetes mellitus in Japanese patients with inadequate glycaemic control: a phase II multicentre, randomized, double-blind, placebo-controlled trial

AIM

Dapagliflozin is a selective sodium-glucose co-transporter 2 (SGLT2) inhibitor under development as a treatment for type 2 diabetes mellitus (T2DM). This study assessed the efficacy and safety of dapagliflozin monotherapy in Japanese T2DM patients with inadequate glycaemic control.

METHODS

Patients (n = 279) were randomized to receive dapagliflozin (1, 2.5, 5 or 10 mg/day) or placebo once daily for 12 weeks. The primary endpoint was change from baseline in haemoglobin A1c (HbA1c) at week 12. Secondary endpoints included change from baseline in fasting plasma glucose (FPG) and proportion of patients achieving HbA1c <7.0% at week 12.

RESULTS

Significant reductions in HbA1c were seen with all dapagliflozin doses (-0.11 to -0.44%) versus placebo (+0.37%). Reductions were also observed in FPG with dapagliflozin (-0.87 to -1.77 mmol/l [-15.61 to -31.94 mg/dl]) versus placebo (+0.62 mmol/l [+11.17 mg/dl]). No significant difference in the proportion of patients achieving HbA1c levels <7.0% was noted with dapagliflozin versus placebo. Adverse events (AEs) were more frequent with dapagliflozin (40.7-53.8%) versus placebo (38.9%) and were mostly mild/moderate in intensity. Three hypoglycaemic events were reported (1 each with placebo, dapagliflozin 2.5 mg and 10 mg). The frequency of signs and symptoms suggestive of urinary tract or genital infections was 0-3.8 and 0-1.8% respectively with dapagliflozin and 1.9 and 0% with placebo. No AEs of pyelonephritis were observed.

CONCLUSIONS

Compared with placebo, dapagliflozin significantly reduced hyperglycaemia over 12 weeks with a low risk of hypoglycaemia in Japanese T2DM patients with inadequate glycaemic control.

Dapagliflozin: a review of its use in type 2 diabetes mellitus

Dapagliflozin (Forxiga®) is the first in a novel class of glucose-lowering agents known as sodium-glucose co-transporter-2 (SGLT2) inhibitors and is used in the treatment of patients with type 2 diabetes. By inhibiting the transporter protein SGLT2 in the kidneys, dapagliflozin reduces renal glucose reabsorption, leading to urinary glucose excretion and a reduction in blood glucose levels. Unlike oral antidiabetic drugs from several other classes, the efficacy of dapagliflozin is independent of insulin secretion and action. Therefore, when used in combination with other antidiabetic drugs, dapagliflozin provides complementary therapy via its unique mechanism of action. A consistent finding across phase III, randomized, double-blind trials in patients with inadequately controlled type 2 diabetes was that dapagliflozin 5 or 10 mg/day for 24 weeks as monotherapy in previously untreated patients, or as add-on combination therapy with metformin, glimepiride, pioglitazone or insulin-based therapy, significantly reduced both glycosylated haemoglobin values (primary endpoint) and fasting plasma glucose levels compared with placebo. Various randomized trials have also shown improvements in postprandial blood glucose with dapagliflozin monotherapy and combination therapy compared with placebo. In addition, dapagliflozin was noninferior to glipizide, in terms of glycaemic control after 52 weeks, when used as add-on therapy in patients with type 2 diabetes that was inadequately controlled with metformin. In most clinical trials, dapagliflozin was associated with reductions in body weight that were statistically superior to placebo or active comparators. Longer-term extension studies indicate that the efficacy of dapagliflozin is maintained for up to ≈2 years. Dapagliflozin was generally well tolerated in clinical trials of 24 or 52 weeks duration and in extension studies of up to ≈2 years. Events suggestive of genital infections and urinary tract infections occurred more frequently among dapagliflozin than placebo recipients. These adverse events are of special interest because they appear to be related to the mechanism of action of dapagliflozin. Dapagliflozin has a low propensity to cause hypoglycaemia, especially when used alone or in combination with metformin, although the incidence of hypoglycaemic events reported with dapagliflozin in clinical trials varied depending on the background therapy. Longer-term tolerability/safety data with dapagliflozin are awaited with interest. In conclusion, dapagliflozin, with its unique and complementary mechanism of action, appears to be an important addition to the therapeutic options for the management of type 2 diabetes, particularly when used as add-on therapy.

Ipragliflozin and other sodium-glucose cotransporter-2 (SGLT2) inhibitors in the treatment of type 2 diabetes: preclinical and clinical data

Sodium-glucose cotransporter-2 (SGLT2) is expressed in the proximal tubules of the kidneys and plays a key role in renal glucose reabsorption. A novel class of antidiabetic medications, SGLT2-selective inhibitors attempt to improve glycemic control in diabetics by preventing glucose from being reabsorbed through SGLT2 and re-entering circulation. Ipragliflozin is an SGLT2 inhibitor in Phase 3 clinical development for the treatment of type 2 diabetes mellitus (T2DM). In this review, we summarize recent animal and human studies on ipragliflozin and other SGLT2 inhibitors including dapagliflozin, canagliflozin, empagliflozin, tofogliflozin, and luseogliflozin. These agents all show potent and selective SGLT2 inhibition in vitro and reduce blood glucose levels and HbA1c in both diabetic animal models and patients with T2DM. SGLT2 inhibitors offer several advantages over other classes of hypoglycemic agents. Due to their insulin-independent mode of action, SGLT2 inhibitors provide steady glucose control without major risk for hypoglycemia and may also reverse β-cell dysfunction and insulin resistance. Other favorable effects of SGLT2 inhibitors include a reduction in both body weight and blood pressure. SGLT2 inhibitors are safe and well tolerated and can easily be combined with other classes of antidiabetic medications to achieve tighter glycemic control. The long-term safety and efficacy of these agents are under evaluation.

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.

Dapagliflozin add-on to metformin in type 2 diabetes inadequately controlled with metformin: a randomized, double-blind, placebo-controlled 102-week trial

BACKGROUND

Management of type 2 diabetes with metformin often does not provide adequate glycemic control, thereby necessitating add-on treatment. In a 24-week clinical trial, dapagliflozin, an investigational sodium glucose cotransporter 2 inhibitor, improved glycemic control in patients inadequately controlled with metformin. The present study is an extension that was undertaken to evaluate dapagliflozin as long-term therapy in this population.

METHODS

This was a long-term extension (total 102 weeks) of a 24-week phase 3, multicenter, randomized, placebo-controlled, double-blind, parallel-group trial. Patients were randomly assigned (1:1:1:1) to blinded daily treatment (placebo, or dapagliflozin 2.5 to 5, or 10 mg) plus open-label metformin (≥1,500 mg). The previously published primary endpoint was change from baseline in glycated hemoglobin (HbA1c) at 24 weeks. This paper reports the follow-up to week 102, with analysis of covariance model performed at 24 weeks with last observation carried forward; a repeated measures analysis was utilized to evaluate changes from baseline in HbA1c, fasting plasma glucose (FPG), and weight.

RESULTS

A total of 546 patients were randomized to 1 of the 4 treatments. The completion rate for the 78-week double-blind extension period was lower for the placebo group (63.5%) than for the dapagliflozin groups (68.3% to 79.8%). At week 102, mean changes from baseline HbA1c (8.06%) were +0.02% for placebo compared with -0.48% (P = 0.0008), -0.58% (P <0.0001), and -0.78% (P <0.0001) for dapagliflozin 2.5 to 5, and 10 mg, respectively. In addition, all dapagliflozin groups had sustained reductions from baseline in FPG (-1.07 to -1.47 mmol/l) and body weight (-1.10 to -1.74 kg) at 102 weeks, whereas increases were noted in placebo-treated patients for both of these outcomes. Events of hypoglycemia were rare and were not severe. Evidence suggestive of genital infection was reported in 11.7% to 14.6% of dapagliflozin patients and 5.1% of placebo patients, with one related discontinuation (dapagliflozin 5 mg). Evidence suggestive of urinary tract infection was reported in 8.0% to 13.3% of dapagliflozin patients and 8.0% of placebo patients, with one related discontinuation (dapagliflozin 2.5 mg).

CONCLUSIONS

Dapagliflozin added to metformin for 102 weeks enabled sustained reductions in HbA1c, FPG, and weight without increased risk of hypoglycemia in patients with type 2 diabetes who were inadequately controlled on metformin alone.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00528879.

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 review of the efficacy and safety of oral antidiabetic drugs

INTRODUCTION

Additional oral antidiabetic agents to metformin, sulfonylureas (SU) and thiazolidinediones (TZD) are approved for the treatment of type 2 diabetes.

AREAS COVERED

The efficacy and safety of metformin, SUs, TZDs, dipeptidyl peptidase-IV (DPP-4) inhibitors, meglitinide analogs, α-glucosidase inhibitors (AGIs), bile-acid sequestrants (BAS) and bromocriptine will be reviewed.

EXPERT OPINION

Several new oral agents have been approved for type 2 diabetes management in recent years. It is important to understand the efficacy and safety of these medications in addition to the older agents to best maximize oral drug therapy for diabetes. Of the recently introduced oral hypoglycemic/antihyperglycemic agents, the DPP-4 inhibitors are moderately efficacious compared with mainstay treatment with metformin with a low side-effect profile and have good efficacy in combination with other oral agents and insulin. They are a recommended alternative when metformin use is limited by gastrointestinal (GI) side effects or when SU treatment results in significant hypoglycemia or weight gain. Meglitinide analogs are limited by their frequent dosing, expense and hypoglycemia (repaglinide > nateglinide), while AGIs are also limited by their dosing schedule and GI side-effect profile. BAS and bromocriptine have the lowest efficacy with regard to HbA(1c) reduction, also are plagued by GI adverse reactions, but have a low risk of hypoglycemia.

Dapagliflozin: a review on efficacy, clinical effectiveness and safety

INTRODUCTION

The prevalence of type 2 diabetes mellitus has reached epidemic proportions. Progressive deterioration in glycaemic control and the current limitations of existing therapies such as weight gain and hypoglycaemia led us to welcome the first of a new class of drugs. Sodium-glucose co-transporter 2 (SGLT2) inhibitors represent a novel mode of therapy independent of insulin secretion or action. By blocking glucose reabsorption in the kidney they lead to an increase in urinary glucose excretion with reduction in plasma glucose levels.

AREAS COVERED

In this article, we will review inhibition of SGLT2 as a novel strategy for the treatment of type 2 diabetes mellitus with dapagliflozin . PubMed and MEDLINE were searched for literature published up to July 2012, for efficacy, clinical effectiveness and safety reports of dapagliflozin.

EXPERT OPINION

Improvement in glycaemic control with a low risk of hypoglycaemia, concomitant weight loss and the potential of lowering of blood pressure make SGLT2 inhibition an attractive approach using dapagliflozin therapy. Many SGLT2 inhibitors are undergoing Phase III clinical trials and more are in Phase I and II clinical trials.

Dapagliflozin has no effect on markers of bone formation and resorption or bone mineral density in patients with inadequately controlled type 2 diabetes mellitus on metformin

AIMS

Dapagliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, reduces hyperglycaemia in patients with type 2 diabetes (T2DM) by increasing urinary glucose excretion. Owing to its mechanism of action, dapagliflozin could potentially affect the renal tubular transportation of bone minerals. Therefore, markers of bone formation and resorption and bone mineral density (BMD) were evaluated in patients with T2DM after 50 weeks of dapagliflozin treatment.

METHODS

This international, multi-centre, randomized, parallel-group, double-blind, placebo-controlled study (ClinicalTrials.gov NCT00855166) enrolled patients with T2DM (women 55-75 years and men 30-75 years; HbA1c 6.5-8.5%; BMI ≥ 25 kg/m(2) ; body weight ≤ 120 kg) whose T2DM was inadequately controlled on metformin. One hundred and eighty-two patients were randomly assigned 1:1 to receive dapagliflozin 10 mg/day or placebo added to open-label metformin for a 24-week double-blind treatment period followed by a 78-week site- and patient-blinded extension period. At week 50, serum markers of bone formation (procollagen type 1 N-terminal propeptide; P1NP) and resorption (C-terminal cross-linking telopeptides of type I collagen; CTX), bone mineral density (BMD) as assessed by standardized Dual-Energy X-ray Absorptiometry (DXA) measurements and adverse events of fracture were evaluated as safety objectives.

RESULTS

One hundred and sixty-five patients (90.7%) completed the first 50 weeks. Compared with placebo, no significant changes from baseline in P1NP, CTX or BMD were identified over 50 weeks of dapagliflozin treatment, with no significant treatment-by-gender interactions. No fractures were reported.

CONCLUSIONS

Dapagliflozin had no effect on markers of bone formation and resorption or BMD after 50 weeks of treatment in both male and post-menopausal female patients whose T2DM was inadequately controlled on metformin.

Systematic review of SGLT2 receptor inhibitors in dual or triple therapy in type 2 diabetes

BACKGROUND

Despite the number of medications for type 2 diabetes, many people with the condition do not achieve good glycaemic control. Some existing glucose-lowering agents have adverse effects such as weight gain or hypoglycaemia. Type 2 diabetes tends to be a progressive disease, and most patients require treatment with combinations of glucose-lowering agents. The sodium glucose co-transporter 2 (SGLT2) receptor inhibitors are a new class of glucose-lowering agents.

OBJECTIVE

To assess the clinical effectiveness and safety of the SGLT2 receptor inhibitors in dual or triple therapy in type 2 diabetes.

DATA SOURCES

MEDLINE, Embase, Cochrane Library (all sections); Science Citation Index; trial registries; conference abstracts; drug regulatory authorities; bibliographies of retrieved papers.

INCLUSION CRITERIA

Randomised controlled trials of SGLT2 receptor inhibitors compared with placebo or active comparator in type 2 diabetes in dual or combination therapy.

METHODS

Systematic review. Quality assessment used the Cochrane risk of bias score.

RESULTS

Seven trials, published in full, assessed dapagliflozin and one assessed canagliflozin. Trial quality appeared good. Dapagliflozin 10 mg reduced HbA1c by -0.54% (weighted mean differences (WMD), 95% CI -0.67 to -0.40) compared to placebo, but there was no difference compared to glipizide. Canagliflozin reduced HbA1c slightly more than sitagliptin (up to -0.21% vs sitagliptin). Both dapagliflozin and canagliflozin led to weight loss (dapagliflozin WMD -1.81 kg (95% CI -2.04 to -1.57), canagliflozin up to -2.3 kg compared to placebo).

LIMITATIONS

Long-term trial extensions suggested that effects were maintained over time. Data on canagliflozin are currently available from only one paper. Costs of the drugs are not known so cost-effectiveness cannot be assessed. More data on safety are needed, with the Food and Drug Administration having concerns about breast and bladder cancers.

CONCLUSIONS

Dapagliflozin appears effective in reducing HbA1c and weight in type 2 diabetes, although more safety data are needed.

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.

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

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are a novel class of glucuretic, antihyperglycemic drugs that target the process of renal glucose reabsorption and induce glucuresis independently of insulin secretion or action. In patients with type 2 diabetes mellitus, SGLT2 inhibitors have been found to consistently reduce measures of hyperglycemia, including hemoglobin A1c, fasting plasma glucose, and postprandial glucose, throughout the continuum of disease. By inducing the renal excretion of glucose and its associated calories, SGLT2 inhibitors reduce weight and have the potential to be disease modifying by addressing the caloric excess that is believed to be one of the root causes of type 2 diabetes mellitus. Additional benefits, including the possibility for combination with insulin-dependent antihyperglycemic drugs, a low potential for hypoglycemia, and the ability to reduce blood pressure, were anticipated from the novel mechanism of action and have been demonstrated in clinical studies. Mechanism-related risks include an increased incidence of urinary tract and genital infections and the possibility of over-diuresis in volume-sensitive patients. Taken together, the results of Phase III clinical studies generally point to a positive benefit-risk ratio across the continuum of diabetes patients. To date, data on dapagliflozin, a selective SGLT2 inhibitor in development, demonstrate that the kidney is an efficacious and safe target for therapy, and that SGLT2 inhibition may have benefits for patients with type 2 diabetes mellitus beyond glycemic control.

Effects of dapagliflozin, an SGLT2 inhibitor, on HbA(1c), body weight, and hypoglycemia risk in patients with type 2 diabetes inadequately controlled on pioglitazone monotherapy

OBJECTIVE

To examine the safety and efficacy of dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, added on to pioglitazone in type 2 diabetes inadequately controlled on pioglitazone.

RESEARCH DESIGN AND METHODS

Treatment-naive patients or those receiving metformin, sulfonylurea, or thiazolidinedione entered a 10-week pioglitazone dose-optimization period with only pioglitazone. They were then randomized, along with patients previously receiving pioglitazone ≥30 mg, to 48 weeks of double-blind dapagliflozin 5 (n = 141) or 10 mg (n = 140) or placebo (n = 139) every day plus open-label pioglitazone. The primary objective compared HbA(1c) change from baseline with dapagliflozin plus pioglitazone versus placebo plus pioglitazone at week 24. Primary analysis was based on ANCOVA model using last observation carried forward; all remaining analyses used repeated-measures analysis.

RESULTS

At week 24, the mean reduction from baseline in HbA(1c) was -0.42% for placebo versus -0.82 and -0.97% for dapagliflozin 5 and 10 mg groups, respectively (P = 0.0007 and P < 0.0001 versus placebo). Patients receiving pioglitazone alone had greater weight gain (3 kg) than those receiving dapagliflozin plus pioglitazone (0.7-1.4 kg) at week 48. Through 48 weeks: hypoglycemia was rare; more events suggestive of genital infection were reported with dapagliflozin (8.6-9.2%) than placebo (2.9%); events suggestive of urinary tract infection showed no clear drug effect (5.0-8.5% for dapagliflozin and 7.9% for placebo); dapagliflozin plus pioglitazone groups had less edema (2.1-4.3%) compared with placebo plus pioglitazone (6.5%); and congestive heart failure and fractures were rare.

CONCLUSIONS

In patients with type 2 diabetes inadequately controlled on pioglitazone, the addition of dapagliflozin further reduced HbA(1c) levels and mitigated the pioglitazone-related weight gain without increasing hypoglycemia risk.

Dapagliflozin: an evidence-based review of its potential in the treatment of type-2 diabetes

Dapagliflozin is a sodium-glucose co-transporter-2 inhibitor that lowers plasma glucose by decreasing its renal reabsorption. The resulting excretion of glucose in the urine (glucosuria) has transformed what was once solely regarded as an adverse facet of diabetes into a potential novel therapeutic strategy. Glucosuria leads to weight loss, due to a reduction in calories, which is thought to rehabilitate insulin sensitivity, at least partially. By acting independently of insulin action or secretion, dapagliflozin appears to avert or minimize two key barriers to optimal glycemic control: hypoglycemia and weight gain. From the clinical studies conducted thus far in patients with type 2 diabetes, dapagliflozin significantly decreases HbA_1c (by ~0.5%–1%, from a baseline of 8%–9%), as well as body weight (~2–3 kg), without increased risk of hypoglycemia. Dapagliflozin thus represents a paradigm shift in the treatment of diabetes. While long-term data on safety and efficacy are forthcoming, the results published to date suggest that this agent has the potential to be another option in the treatment of diabetes treatments. This article examines the evidence currently available on the efficacy and safety of dapagliflozin.

Dapagliflozin for the treatment of type 2 diabetes

OBJECTIVE

To review the literature and describe the pharmacologic, pharmacokinetic, and pharmacodynamic properties; clinical safety; and efficacy of dapagliflozin, a new drug currently under review by the Food and Drug Administration (FDA) for the treatment of type 2 diabetes.

DATA SOURCES

A MEDLINE (1995-November 2011) and ClinicalTrials.gov search was conducted using the terms dapagliflozin, sodium-glucose cotransporter 2 inhibitor, and SGLT2 inhibitor. Reference citations from publications identified were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

All English-language studies, including abstracts, evaluating dapagliflozin use in humans were included in this review.

DATA SYNTHESIS

Dapagliflozin is the first-in-class oral sodium-glucose cotransporter 2 (SGLT2) inhibitor that represents a new potential therapeutic option for the treatment of type 2 diabetes mellitus. Its mechanism of action is insulin- and insulin-sensitivity independent. Preliminary data suggest that dapagliflozin decreases hemoglobin A(1c), fasting plasma glucose, and postprandial plasma glucose, while also promoting weight loss. In Phase 1, 2, and 3 clinical trials, dapagliflozin has exhibited a safety and tolerability profile similar to that of placebo.

CONCLUSIONS

Dapagliflozin is a novel oral antihyperglycemic agent that has demonstrated promise as monotherapy and as synergistic combination therapy with currently available agents in Phase 3 clinical trials. On January 19, 2012, the FDA issued a complete response letter to AstraZeneca and Bristol-Myers Squibb regarding the new drug application for dapagliflozin. The FDA is requesting additional clinical data-from ongoing studies and potentially new clinical trials-to better describe the risk-benefit profile of the drug. Both manufacturers remain committed to the development of dapagliflozin, and there are currently 8 Phase 3 trials ongoing. Dapagliflozin has the potential to be the next new oral agent in the diabetes drug armamentarium.

Effects of dapagliflozin on body weight, total fat mass, and regional adipose tissue distribution in patients with type 2 diabetes mellitus with inadequate glycemic control on metformin

CONTEXT

Dapagliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, reduces hyperglycemia in patients with type 2 diabetes mellitus (T2DM) by increasing urinary glucose excretion, and weight loss is a consistent associated finding.

OBJECTIVES

Our objectives were to confirm weight loss with dapagliflozin and establish through body composition measurements whether weight loss is accounted for by changes in fat or fluid components.

DESIGN AND SETTING

This was a 24-wk, international, multicenter, randomized, parallel-group, double-blind, placebo-controlled study with ongoing 78-wk site- and patient-blinded extension period at 40 sites in five countries.

PATIENTS

Included were 182 patients with T2DM (mean values: women 63.3 and men 58.6 yr of age; hemoglobin A1c 7.17%, body mass index 31.9 kg/m2, and body weight 91.5 kg) inadequately controlled on metformin.

INTERVENTION

Dapagliflozin 10 mg/d or placebo was added to open-label metformin for 24 wk.

MAIN OUTCOME MEASURES

Primary endpoint was total body weight (TBW) change from baseline at wk 24. Key secondary endpoints were waist circumference and dual-energy x-ray absorptiometry total-body fat mass (FM) changes from baseline at wk 24, and patient proportion achieving body weight reduction of at least 5% at wk 24. In a subset of patients, magnetic resonance assessment of visceral adipose tissue (VAT) and sc adipose tissue (SAT) volume and hepatic lipid content were also evaluated.

RESULTS

At wk 24, placebo-corrected changes with dapagliflozin were as follows: TBW, -2.08 kg [95% confidence interval (CI)=-2.84 to -1.31; P<0.0001]; waist circumference, -1.52 cm (95% CI=-2.74 to -0.31; P=0.0143); FM, -1.48 kg (95% CI=-2.22 to -0.74; P=0.0001); proportion of patients achieving weight reduction of at least 5%, +26.2% (95% CI=15.5 to 36.7; P<0.0001); VAT, -258.4 cm3 (95% CI=-448.1 to -68.6; nominal P=0.0084); SAT, -184.9 cm3 (95% CI=-359.7 to -10.1; nominal P=0.0385). In the dapagliflozin vs. placebo groups, respectively, serious adverse events were reported in 6.6 vs. 1.1%; events suggestive of vulvovaginitis, balanitis, and related genital infection in 3.3 vs. 0%; and lower urinary tract infections in 6.6 vs. 2.2%.

CONCLUSIONS

Dapagliflozin reduces TBW, predominantly by reducing FM, VAT and SAT in T2DM inadequately controlled with metformin.

Renal hyperfiltration related to diabetes mellitus and obesity in human disease

High intraglomerular pressure is associated with renal hyperfiltration, leading to the initiation and progression of kidney disease in experimental models of diabetes mellitus (DM). In humans, hyperfiltration is observed in patients with type 1 and type 2 DM, and is also seen in patients with pre-diabetic conditions, such as the metabolic syndrome. From a mechanistic perspective, both vascular and tubular factors likely contribute to the pathogenesis of hyperfiltration. Until now, human studies have primarily focused on the use of medications that inhibit the renin angiotensin system to reduce efferent vasoconstriction and thereby improve hyperfiltration. More recent advances in the development of investigational adenosine antagonists and inhibitors of sodium glucose co-transport may help to elucidate tubular factors that contribute to afferent vasodilatation. In this review, we summarize available data from experimental and human studies of type 1 and type 2 DM and obesity to provide an overview of factors that contribute to the hyperfiltration state. We have focused on the renin angiotensin system, cyclooxygenase-2 system, nitric oxide, protein kinase C and endothelin as vascular determinants of hyperfiltration. We also discuss relevant tubular factors, since experimental models have suggested that inhibition of sodium-glucose cotransport may be renoprotective.

Clinical potential of sodium-glucose cotransporter 2 inhibitors in the management of type 2 diabetes

BACKGROUND

The kidney plays an important role in glucose metabolism, and has been considered a target for therapeutic intervention. The sodium-glucose cotransporter type 2 (SGLT2) mediates most of the glucose reabsorption from the proximal renal tubule. Inhibition of SGLT2 leads to glucosuria and provides a unique mechanism to lower elevated blood glucose levels in diabetes. The purpose of this review is to explore the physiology of SGLT2 and discuss several SGLT2 inhibitors which have clinical data in patients with type 2 diabetes.

METHODS

We performed a PubMed search using the terms "SGLT2" and "SGLT2 inhibitor" through April 10, 2012. Published articles, press releases, and abstracts presented at national and international meetings were considered.

RESULTS

SGLT2 inhibitors correct a novel pathophysiological defect, have an insulin-independent action, are efficacious with glycosylated hemoglobin reduction ranging from 0.5% to 1.5%, promote weight loss, have a low incidence of hypoglycemia, complement the action of other antidiabetic agents, and can be used at any stage of diabetes. They are generally well tolerated. However, due to side effects, such as repeated urinary tract and genital infections, increased hematocrit, and decreased blood pressure, appropriate patient selection for drug initiation and close monitoring after initiation will be important. Results of ongoing clinical studies of the effect of SGLT2 inhibitors on diabetic complications and cardiovascular safety are crucial to determine the risk-benefit ratio. A recent decision by the Committee for Medicinal Products for Human Use of the European Medicines Agency has recommended approval of dapagliflozin for the treatment of type 2 diabetes as an adjunct to diet and exercise, in combination with other glucose-lowering medicinal products, including insulin, and as a monotherapy for metformin-intolerant patients. Clinical research also remains to be carried out on the long-term effects of glucosuria and other potential effects of SGLT2 inhibitors, especially in view of the observed increase in the incidence of bladder and breast cancer. SGLT2 inhibitors represent a promising approach for the treatment of diabetes, and could potentially be an addition to existing therapies.

SGLT-2 inhibitors in development for type 2 diabetes treatment

The prevalence of type 2 diabetes is increasing worldwide. The majority of currently available glucose-lowering agents work via insulin-dependent mechanisms and have significant limitations. Hence, there is a need for newer treatments utilizing novel therapeutic targets. Drugs which inhibit the sodium glucose cotransporter in the renal tubules (SGLT-2 inhibitors), represent a novel class of drugs under development. By inhibiting SGLT-2, they promote increased renal glucose excretion and thereby calorie loss with improved glycemic control and weight loss. Dapagliflozin is most advanced in development of this new drug class and currently undergoing phase 3 trials. In addition to its glucose lowering effect, dapagliflozin appears to have favorable impacts on weight and blood pressure, with low risk of hypoglycemia. However, as with all new treatments, long-term safety is an issue. Clinical trials showed increased risk of genital and possibly urinary infections with dapgliflozin. Furthermore, concerns have arisen regarding a possible increased incidence of breast and bladder cancer in patients on dapagliflozin. However, it needs further investigation to confirm or refute whether these concerns are concrete.