New clinical trial designs for establishing drug efficacy and safety in a precision medicine era.

Despite advances in pharmacotherapy, diabetic kidney disease (DKD) remains associated with a high burden of micro- and macrovascular complications often leading to premature mortality. New therapies are highly desirable to mitigate the burden of this disease. However, there are a number of barriers that hamper drug development in DKD. These include, amongst others, the lengthy and complex clinical trials required to prove drug efficacy and safety, inefficiencies in clinical trial conduct, and the high costs associated with these development programs. In this review a number of aspects are discussed, aiming to identify opportunities to transform and innovate drug development for DKD. Many clinical trials in DKD, as well as in other areas, face difficulties in timely and efficient enrolment of participants. To address this issue a network of sites should be created that are continuously recruiting individuals with DKD and collecting crucial information that can be used to understand prognosis and prognostic factors, and more importantly to serve as a pool of participants for recruitment to randomized trials. Second, the current clinical endpoints are late events in the progression of DKD. Endpoints based on lesser declines in estimated glomerular filtration rate (eGFR) or changes in albuminuria can shorten follow-up and/or lead to smaller and cheaper trials. Enrichment by enrolling clinical trial populations based on biomarker profiles is another approach that may facilitate clinical trial efficiency and conduct. Biomarkers can be used to individualize treatment by targeting populations more likely to respond leading to smaller and more efficient trials. Finally, using new trial design such as basket, umbrella or more broadly platform trials to assess a number of therapies simultaneously offers the potential to transform the drug development process in DKD. There are a number of opportunities to transform development approaches for new therapies for DKD. Platform trials along with appropriate biomarker-based enrichment strategies offer the possibility to foster drug development in a precision medicine era.

Effects of canagliflozin versus glimepiride on adipokines and inflammatory biomarkers in type 2 diabetes.

OBJECTIVE: Type 2 diabetes and obesity are pro-inflammatory states associated with increased risk of cardiovascular disease. Canagliflozin, an SGLT2 inhibitor, demonstrated superiority in lowering HbA1c versus glimepiride with less hypoglycemia and greater weight reduction via loss of fat mass in a 52-week trial of type 2 diabetes patients. This post hoc, exploratory analysis assessed the effects of canagliflozin versus glimepiride on select adipokines, inflammatory biomarkers, and chemokines. METHODS: Changes from baseline to Week 52 in serum leptin, adiponectin, IL-6, TNFα, CRP, PAI-1, VCAM-1, and MCP-1 were measured in a randomly selected subset of type 2 diabetes patients on metformin receiving canagliflozin 300 mg (n = 100) or glimepiride (n = 100) in the overall study. Correlations between change in biomarkers and change in select metabolic and anthropometric variables were assessed. RESULTS: At Week 52, canagliflozin decreased median serum leptin by 25% (95% CI: -34%, -15%) and increased median serum adiponectin by 17% (95% CI: 11%, 23%) compared with glimepiride. There was a 22% reduction in median serum IL-6 (95% CI: -34%, -10%) and a 7% increase in median serum TNFα (95% CI: 1%, 12%) with canagliflozin versus glimepiride. No between-group differences were observed with the other biomarkers. The decrease in serum leptin with canagliflozin was correlated with change in weight (r ≥ 0.3) only; the increase in adiponectin and decrease in IL-6 with canagliflozin occurred independently of changes in HbA1c, weight, or lipids. CONCLUSIONS: These results indicate that canagliflozin may improve adipose tissue function and induce changes in serum leptin, adiponectin, and IL-6 that favorably impact insulin sensitivity and cardiovascular disease risk.

Dapagliflozin lowers blood pressure in hypertensive and non-hypertensive patients with type 2 diabetes.

The effect of dapagliflozin on blood pressure was evaluated in non-hypertensive (<140 mm Hg) and hypertensive (⩾140 mm Hg) patients with type 2 diabetes mellitus. Data were pooled from 13 placebo-controlled studies. Patients received dapagliflozin 10 mg/day (n = 2360) or placebo (n = 2295) for up to 24 weeks. Dapagliflozin was associated with placebo-subtracted changes from baseline in systolic and diastolic blood pressures of -3.6 and -1.2 mm Hg, respectively, in hypertensive patients and -2.6 and -1.2 mm Hg, respectively, in non-hypertensive patients. At 24 weeks, a similar proportion of patients experienced measured orthostatic reactions with dapagliflozin versus placebo in hypertensive (6.1% and 6.6%, respectively) and non-hypertensive (4.0% and 4.2%) patients. No clinically relevant difference was observed between dapagliflozin and placebo in heart rate. In conclusion, dapagliflozin 10 mg induces a modest reduction in blood pressure compared with placebo in patients with diabetes with a low risk of orthostatic reactions, regardless of baseline blood pressure.

Exploring the potential of the SGLT2 inhibitor dapagliflozin in type 1 diabetes: a randomized, double-blind, placebo-controlled pilot study.

OBJECTIVE: Insulin adjustments to maintain glycemic control in individuals with type 1 diabetes often lead to wide glucose fluctuations, hypoglycemia, and increased body weight. Dapagliflozin, an insulin-independent sodium-glucose cotransporter 2 (SGLT2) inhibitor, increases glucosuria and reduces hyperglycemia in individuals with type 2 diabetes. The primary objective of this study was to assess short-term safety of dapagliflozin in combination with insulin; secondary objectives included pharmacokinetic, pharmacodynamic, and efficacy parameters. RESEARCH DESIGN AND METHODS: A 2-week, dose-ranging, randomized, double-blind, placebo-controlled proof-of-concept study randomly assigned 70 adults with type 1 diabetes (HbA1c 7-10%), who were receiving treatment with stable doses of insulin, to one of four dapagliflozin doses (1, 2.5, 5, or 10 mg) or placebo. The insulin dose was not proactively reduced at randomization but could be adjusted for safety reasons. RESULTS: Sixty-two patients (88.6%) completed the study. Any hypoglycemia was common across all treatments (60.0-92.3%); one major event of hypoglycemia occurred with dapagliflozin 10 mg. No diabetic ketoacidosis occurred. Pharmacokinetic parameters were similar to those observed in patients with type 2 diabetes. Glucosuria increased by 88 g/24 h (95% CI 55 to 121) with dapagliflozin 10 mg and decreased by -21.5 g/24 h (95% CI -53.9 to 11.0) with placebo. Changes from baseline with dapagliflozin 10 mg by day 7 were as follows: -2.29 mmol/L (95% CI -3.71 to -0.87 [-41.3 mg/dL; 95% CI -66.9 to -15.7]) for 24-h daily average blood glucose; -3.77 mmol/L (95% CI -6.09 to -1.45 [-63.1 mg/dL; 95% CI -111.5 to -14.8]) for mean amplitude of glycemic excursion; and -16.2% (95% CI -29.4 to -0.5) for mean percent change in total daily insulin dose. Corresponding changes with placebo were as follows: -1.13 mmol/L (95% CI -3.63 to 1.37), -0.45 mmol/L (95% CI -4.98 to 4.08), and 1.7% (95% CI -22.8 to 33.9), respectively. However, for every efficacy parameter, the 95% CIs for all dapagliflozin doses overlapped those for placebo. CONCLUSIONS: This exploratory study of dapagliflozin in adults with type 1 diabetes demonstrated acceptable short-term tolerability and expected pharmacokinetic profiles and increases in urinary glucose excretion. Within the dapagliflozin groups, dose-related reductions in 24-h glucose, glycemic variability, and insulin dose were suggested, which provide hope that SGLT2 inhibition may prove in larger randomized controlled trials to be efficacious in reducing hyperglycemia in type 1 diabetes.

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

BACKGROUND: Dapagliflozin reduces hyperglycaemia in patients with type 2 diabetes mellitus (T2DM) by increasing urinary glucose excretion. OBJECTIVES: This study determined the overall safety profile of dapagliflozin in T2DM. METHODS: Safety of dapagliflozin in pooled analyses of phase IIb/III studies was evaluated. Patients received comparator or dapagliflozin as monotherapy, add-on to antidiabetic therapy, or as initial combination with metformin. Proportions of patients with adverse events (AEs) and prespecified parameters related to previous clinical observations and dapagliflozin's action were assessed. The principal analysis used data from 12 placebo-controlled studies. Rare events were assessed across phase IIb/III studies, including special populations, comparator-controlled trials and ongoing long-term extensions. RESULTS: In placebo-controlled studies, hypoglycaemia was more common with dapagliflozin (11.8 %) than placebo (7.0 %), with imbalance driven by add-on of dapagliflozin to sulfonylurea or insulin. Urinary tract infections (4.8 vs 3.7 %), vulvovaginitis/balanitis and related infections (5.1 vs 0.9 %), and non-serious volume-related events (0.8 vs 0.4 %) occurred more often with dapagliflozin than placebo. No substantial AEs were seen on electrolytes or renal function. Pyelonephritis was rare and balanced among treatments; there were no imbalances in fractures or liver test elevations. Overall incidence of malignancies was balanced between groups. The incidence rate ratios of malignancy in certain organ systems were slightly lower for dapagliflozin (renal tract, female reproductive) and in others were slightly lower for control (breast, prostate, bladder). Most AEs associated with dapagliflozin were mild/moderate and related to the mechanism of action. CONCLUSION: Dapagliflozin has a favourable and predictable tolerability profile, with reported events related to its mechanism of action.

Genital and urinary tract infections in diabetes: impact of pharmacologically-induced glucosuria.

Predisposition to genital infections and urinary tract infections (UTIs) in type 2 diabetes mellitus (T2DM) results from several factors such as glucosuria, adherence of bacteria to the uroepithelium and immune dysfunction. The tendency to develop these infections could be even higher in patients with T2DM treated with the emerging class of sodium-glucose cotransporter-2 (SGLT2) inhibitors. Studies have shown that pharmacologically-induced glucosuria with SGLT2 inhibitors raises the risk of developing genital infections and, to a relatively lesser extent, UTIs. However, a definitive dose relationship of the incidence of these infections with the SGLT2 doses is not evident in the existing data. Therefore, the precise role of glucosuria as a causative factor for these infections is yet to be fully elucidated.

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.

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.

Changes in insulin sensitivity and insulin secretion with the sodium glucose cotransporter 2 inhibitor dapagliflozin.

AIM: This randomized, double-blind, placebo-controlled parallel-group study assessed the effects of sodium glucose cotransporter 2 inhibition by dapagliflozin on insulin sensitivity and secretion in subjects with type 2 diabetes mellitus (T2DM), who had inadequate glycemic control with metformin (with or without an insulin secretagogue). SUBJECTS AND METHODS: Forty-four subjects were randomized to receive dapagliflozin 5 mg or matching placebo once daily for 12 weeks. Subjects continued stable doses of background antidiabetes medication throughout the study. Insulin sensitivity was assessed by measuring the glucose disappearance rate (GDR) during the last 40 min of a 5-h hyperinsulinemic, euglycemic clamp. Insulin secretion was determined as the acute insulin response to glucose (AIRg) during the first 10 min of a frequently sampled intravenous glucose tolerance test. Where noted, data were adjusted for baseline values and background antidiabetes medication. RESULTS: An adjusted mean increase from baseline in GDR (last observation carried forward), at Week 12, was observed with dapagliflozin (7.98%) versus a decrease with placebo (-9.99%). The 19.97% (95% confidence interval 5.75-36.10) difference in GDR versus placebo was statistically significant (P=0.0059). A change from baseline in adjusted mean AIRg of 15.39 mU/L min was observed with dapagliflozin at Week 12, versus -12.73 mU/L min with placebo (P=0.0598). Over 12 weeks, numerical reductions from baseline in glycosylated hemoglobin (HbA1c), fasting plasma glucose, and body weight were observed with dapagliflozin (-0.38%, -0.39 mmol/L, and -1.58%, respectively) versus slight numerical increases with placebo (0.03%, 0.26 mmol/L, and 0.62%, respectively). CONCLUSIONS: In patients with T2DM and inadequate glycemic control, dapagliflozin treatment improved insulin sensitivity in the setting of reductions in HbA1c and weight.

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.

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.

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.

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.

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.

Targeting renal glucose reabsorption for the treatment of type 2 diabetes mellitus using the SGLT2 inhibitor dapagliflozin.

Sodium-glucose co-transporter 2 (SGLT2) plays a key role in glucose homeostasis as the key transporter responsible for most renal glucose reabsorption in the proximal tubules of the kidney. Dapagliflozin is a potent, selective, and reversible inhibitor of SGLT2 that lowers blood glucose levels in an insulin-independent fashion. This novel agent has been studied extensively in patients with type 2 diabetes mellitus (T2DM). In these clinical trials, dapagliflozin significantly decreased glycated hemoglobin and fasting plasma glucose levels when administered alone or as add-on treatment in patients who were already receiving metformin, a sulfonylurea (glimepiride), pioglitazone, or insulin. Moreover, dapagliflozin decreased body weight when taken as monotherapy or in combination with metformin, a sulfonylurea, or insulin, and mitigated weight gain in patients receiving pioglitazone. Consistent with preclinical toxicology studies, dapagliflozin has a manageable adverse event profile that is largely predictable from its mechanism of action. While there are no clinically significant negative effects on renal function or electrolytes, dapagliflozin treatment is associated with increased frequencies of urinary tract infections and vulvovaginitis/balanitis. With a mechanism of action that is distinct from and complementary to that of existing antihyperglycemic therapies, dapagliflozin is an effective antihyperglycemic agent that is well tolerated and may enhance weight loss. As such, dapagliflozin promises to become an important adjunctive therapy for comprehensive treatment of T2DM.

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.

Safety and efficacy of saxagliptin in combination with submaximal sulphonylurea versus up-titrated sulphonylurea over 76 weeks.

To assess the long-term efficacy and safety of saxagliptin in patients with type 2 diabetes mellitus inadequately controlled on sulphonylurea monotherapy, 768 patients were randomised to saxagliptin 2.5 or 5 mg in combination with glyburide 7.5 mg versus placebo added to up-titrated glyburide over 76 weeks (24 weeks plus 52-week extension) in this phase 3, double-blind, placebo-controlled trial; 557 patients completed the study, 142 without being rescued. At 76 weeks, adjusted mean changes from baseline HbA(1C) (repeated measures model) (95% confidence interval) for saxagliptin 2.5 mg, saxagliptin 5 mg, and up-titrated glyburide were 0.11% (-0.05, 0.27), 0.03% (-0.14, 0.19), and 0.69% (0.47, 0.92), respectively (post hoc and nominal p < 0.0001 for saxagliptin 2.5 and 5 mg vs. up-titrated glyburide). Adverse event frequency was similar in all treatment groups; reported hypoglycaemia event rates were 24.2%, 22.9%, and 20.6% with saxagliptin 2.5 mg, saxagliptin 5 mg, and up-titrated glyburide, respectively. Saxagliptin plus glyburide provided sustained incremental efficacy compared with up-titrated glyburide over 76 weeks, and was generally well tolerated.

Glucose dynamics and mechanistic implications of SGLT2 inhibitors in animals and humans.

Glucose is freely filtered in the glomeruli before being almost entirely reabsorbed into circulation from the proximal renal tubules. The sodium-glucose cotransporter 2 (SGLT2), present in the S1 segment of the proximal tubule, is responsible for the majority of glucose reabsorption. SGLT2 inhibitors reduce glucose reabsorption and increase urinary glucose excretion. In animal models and humans with type 2 diabetes, this effect is associated with reduced fasting and postprandial blood glucose levels, and reduced hemoglobin A1c. Animal studies suggest that reduction of hyperglycemia with SGLT2 inhibitors may also improve insulin sensitivity and preserve ß-cell function. Urinary excretion of excess calories with SGLT2 inhibitors is also associated with reduction in body weight. Modest reductions in blood pressure have been noted with SGLT2 inhibitors, consistent with a mild diuretic action. Some C-glucoside SGLT2 inhibitors, such as dapagliflozin, have pharmacokinetic properties that make them amenable to once-daily dosing.

Synergy between scientific advancement and technological innovation, illustrated by a mechanism-based model characterizing sodium-glucose cotransporter-2 inhibition.

Advances in experimental medicine and technological innovation during the past century have brought tremendous progress in modern medicine and generated an ever-increasing amount of data from bench and bedside. The desire to extend scientific knowledge motivates effective data integration. Technological innovation makes this possible, which in turn accelerates the advancement in science. This mutually beneficial interaction is illustrated by the development of an expanded mechanism-based model for understanding a novel mechanism, sodium-glucose cotransporter-2 SGLT2 inhibition for potential treatment of type 2 diabetes mellitus.