The effect of renal function on the pharmacokinetics and pharmacodynamics of enavogliflozin, a potent and selective sodium-glucose cotransporter-2 inhibitor, in type 2 diabetes.

AIMS: To explore the effect of renal function on the pharmacokinetic (PK) and pharmacodynamic (PD) profile and safety of enavogliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, in patients with type 2 diabetes mellitus (T2DM). METHODS: An open-label, two-part clinical trial was conducted in T2DM patients, stratified by renal function: Group 1, normal renal function; Group 2, mild renal impairment (RI); Group 3, moderate RI; and Group 4, severe RI. In Part A, Groups 2 and 4 received enavogliflozin 0.5 mg once. In Part B, Groups 1 and 3 received enavogliflozin 0.5 mg once daily for 7 days. Serial blood and timed urine samples were collected to analyse the PK and PD characteristics of enavogliflozin. Pearson's correlation coefficients were calculated to assess the correlations between PK or PD parameters and creatinine clearance (CrCL). RESULTS: A total of 21 patients completed the study as planned. The area under the curve (AUC) for enavogliflozin was not significantly correlated with CrCL, although the maximum concentration slightly decreased as renal function decreased. By contrast, daily urinary glucose excretion (UGE) was positively correlated with CrCL after both single- (r = 0.7866, p < 0.0001) and multiple-dose administration (r = 0.6606, p = 0.0438). CONCLUSIONS: Systemic exposure to oral enavogliflozin 0.5 mg was similar among the patients with T2DM regardless of their renal function levels. However, the glucosuric effect of enavogliflozin decreased with RI. Considering the UGE observed and approved therapeutic use of other SGLT2 inhibitors, the efficacy of enavogliflozin with regard to glycaemic control could be explored in patients with mild and moderate RI (estimated glomerular filtration rate ≥30 or ≥45 mL/min/1.73 m2) in a subsequent larger study.

Renal histology of Fanconi syndrome associated with adefovir dipivoxil: A case report.

A sporadic occurrence of Fanconi syndrome associated with adefovir dipivoxil (ADV) has been reported, particularly when confirmed by renal biopsy. This study presents the case of a 53-year-old man who had been taking ADV 10 mg daily for 10 years to treat chronic hepatitis B (CHB) and subsequently developed Fanconi syndrome. The clinical manifestations included hypophosphatemic osteomalacia, glucosuria, renal tubular acidosis, low-molecular-weight proteinuria, and renal insufficiency. Renal biopsy revealed significant injury to proximal tubular epithelial cells, including vacuolar degeneration and regeneration of tubular epithelial cells. The ultrastructural pathology indicated severe morphological abnormalities of mitochondria, such as densely packed and enlarged mitochondria, with loss, blunting, and disordered arrangement of cristae. Following discontinuation of ADV and supplementation with oral phosphate, hypophosphatemia, glucosuria, and proteinuria were resolved. These findings support the previous hypothesis that ADV-induced nephrotoxicity may involve mitochondrial injury.

The differential effects of ertugliflozin on glucosuria and natriuresis biomarkers: Prespecified analyses from VERTIS CV.

AIMS: This prespecified exploratory analyses from VERTIS CV (NCT01986881) aimed to assess the effects of the sodium-glucose cotransporter-2 (SGLT2) inhibitor ertugliflozin on glucosuria-related (glycated haemoglobin [HbA1c], uric acid, body weight) and natriuresis-related (blood pressure, haemoglobin, haematocrit, serum albumin) biomarkers according to kidney function risk category. MATERIALS AND METHODS: Patients with type 2 diabetes and atherosclerotic cardiovascular disease were randomized to placebo, ertugliflozin 5 mg, or ertugliflozin 15 mg (1:1:1). Analyses compared placebo (n = 2747) versus ertugliflozin (pooled; n = 5499) on glucosuria- and natriuresis-related biomarkers according to baseline estimated glomerular filtration rate (eGFR) subgroup and Kidney Disease: Improving Global Outcomes in Chronic Kidney Disease (KDIGO CKD) risk category. RESULTS: Patients were classified according to KDIGO CKD low- (49%), moderate- (32%) and high-/very-high-risk categories (19%), and eGFR groups 1 (25%), 2 (53%) and 3 (19%). At Week 18, the high-/very-high-risk category had a smaller placebo-subtracted least squares mean (LSM) change from baseline (95% confidence interval) in HbA1c (-0.34 [-0.43, -0.25]) compared with the low- and moderate-risk categories (-0.54 [-0.60, -0.49] and - 0.47 [-0.54, -0.40], respectively). This pattern was maintained throughout the study (Pinteraction  = 0.0001). Similar patterns based on baseline eGFR G stage were observed. Placebo-subtracted LSM changes from baseline in uric acid were lowest in the high-/very-high-risk category at Weeks 6 and 18, but the pattern was not maintained after Week 156 (Pinteraction  = 0.15). Effects of ertugliflozin on body weight and natriuresis-related biomarkers did not differ across KDIGO CKD categories. CONCLUSIONS: In VERTIS CV, ertugliflozin was associated with physiologically favourable changes in glucosuria- and natriuresis-related biomarkers. Glycaemic efficacy of ertugliflozin was attenuated in patients with higher chronic kidney disease (CKD) risk. Effects on other biomarkers were consistent, regardless of CKD risk stage.

Bittersweet: infective complications of drug-induced glycosuria in patients with diabetes mellitus on SGLT2-inhibitors: two case reports.

BACKGROUND: Sodium-glucose co-transporter 2 (SGLT2) inhibitors are novel hypoglycemic agents which reduce reabsorption of glucose at the renal proximal tubule, resulting in significant glycosuria and increased risk of genital mycotic infections (GMI). These infections are typically not severe as reported in large systematic reviews and meta-analyses of the medications. These reviews have also demonstrated significant cardiovascular benefits through other mechanisms of action, making them attractive options for the management of Type 2 diabetes mellitus (T2DM). We present two cases with underlying abnormalities of the urogenital tract in which the GMI were complicated and necessitated cessation of the SGLT2 inhibitor. CASE PRESENTATIONS: Both cases are patients with T2DM on empagliflozin, an SGLT2 inhibitor. The first case is a 64 year old man with Candida albicans balanitis and candidemia who was found to have an obstructing renal calculus and prostatic abscess requiring operative management. The second case describes a 72 year old man with Candida glabrata candidemia who was found to have prostatomegaly, balanitis xerotica obliterans with significant urethral stricture and bladder diverticulae. His treatment was more complex due to fluconazole resistance and concerns about urinary tract penetration of other antifungals. Both patients recovered following prolonged courses of antifungal therapy and in both cases the SGLT2 inhibitor was ceased. CONCLUSIONS: Despite their cardiovascular benefits, SGLT2 inhibitors can be associated with complicated fungal infections including candidemia and patients with anatomical abnormalities of the urogenital tract may be more susceptible to these infections as demonstrated in these cases. Clinicians should be aware of their mechanism of action and associated risk of infection and prior to prescription, assessment of urogenital anatomical abnormalities should be performed to identify patients who may be at risk of complicated infection.

Trimetazidine Protects from Mercury-Induced Kidney Injury.

INTRODUCTION: The presence of mercury in the environment is a worldwide concern. Inorganic mercury is present in industrial materials, is employed in medical devices, is widely used in batteries, is a component of fluorescent light bulbs, and it has been associated with human poisoning in gold mining areas. The nephrotoxicity induced by inorganic mercury is a relevant health problem mainly in developing countries. The primary mechanism of mercury toxicity is oxidative stress. Trimetazidine (TMZ) is an anti-ischemic drug, which inhibits cellular oxidative stress, eliminates oxygen-free radicals, and improves lipid metabolism. The aim of this study was to evaluate whether the administration of TMZ protects against mercuric chloride (HgCl2) kidney damage. METHODS: Adult male Wistar rats received only HgCl2 (4 mg/kg bw, sc) (Hg group, n = 5) or TMZ (3 mg/kg bw, ip) 30 min before HgCl2 administration (4 mg/kg bw, sc) (TMZHg group, n = 7). Simultaneously, a control group of rats (n = 4) was studied. After 4 days of HgCl2 injection, urinary flow, urea and creatinine (Cr) plasma levels, Cr clearance, urinary glucose, and sodium-dicarboxylate cotransporter 1 (NaDC1) in urine were determined. Lipid peroxidation (MDA) and glutathione (GSH) levels were measured in kidney homogenates. RESULTS: Rats only treated with HgCl2 showed an increase in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, and NaDC1 urinary excretion as compared with the control group and a decrease in Cr clearance. TMZHg group showed a decrease in urea and Cr plasma levels, urinary flow, fractional excretion of water, glucosuria, NaDC1 urinary excretion, and an increase in Cr clearance when compared to the Hg group. Moreover, MDA and GSH levels observed in Hg groups were decreased and increased, respectively, by TMZ pretreatment. CONCLUSION: TMZ exerted a renoprotective action against HgCl2-induced renal injury, which might be mediated by the reduction of oxidative stress. Considering the absence of toxicity of TMZ, its clinical application against oxidative damage due to HgCl2-induced renal injury should be considered. The fact that TMZ is commercially available should simplify and accelerate the translation of the present data "from bench to bedside." In this context, TMZ become an interesting new example of drug repurposing.

Tubular Injury Causing Protracted Glycosuria Following Withdrawal of a Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor: A Possible Role in the Development of Protracted Hypoglycemia and Ketoacidosis.

We herein present the case of a 45-year-old diabetic woman who developed diabetic ketoacidosis following the administration of dapagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor. The patient had been diagnosed with diabetes three years previously and was being treated with multiple daily injections of insulin. Metformin hydrochloride and dapagliflozin were added seven months and 11 months later, respectively. Her clinical course was uneventful until the onset of influenza. She then discontinued insulin and oral medications voluntarily. On arrival at the hospital, she was found to be in a state of ketoacidosis, and promptly received insulin and saline infusion. In retrospect, the initial amount of glucose infused was insufficient, and the hypoglycemia was thought to have been prolonged. This phenomenon may also have affected her long-term urinary glucose excretion. Her urinary L-type fatty acid-binding protein (L-FABP) level was found to be markedly elevated (48.8 µg/g·Cr, reference value < 8.4 µg/g·Cr) as was her urinary ß2-microglobulin level (9,230 µg/L, reference value < 230 µg/L). Patients with SGLT-2 inhibitor-associated diabetic ketoacidosis often exhibit protracted hyperglycosuria, in which acute proximal renal tubular dysfunction is considered to be etiologically implicated.

Renal proximal tubulopathy in an HIV-infected patient treated with tenofovir alafenamide and gentamicin: a case report.

BACKGROUND: The nucleotide reverse transcriptase inhibitor Tenofovir Alafenamide (TAF) is a novel pro-drug of tenofovir (TFV) and possesses a superior renal safety profile compared with tenofovir disoproxil fumerate (TDF). Due to unique pharmacokinetic characteristics, treatment with TAF is not associated with significant renal proximal tubular accumulation of TFV. TAF is associated with a lower risk of acute kidney injury, chronic kidney disease, proteinuria and renal proximal tubular dysfunction than treatment with TDF. No cases of Fanconi syndrome have been reported in clinical trials of TAF. It is unknown whether treatment with TAF can lead to accumulation of TFV in proximal tubular cells and cause nephrotoxicity under certain clinical circumstances. CASE PRESENTATION: Here we report the case of a patient on stable TAF-based antiretroviral therapy with for HIV-1 infection who developed proximal tubulopathy when treated with gentamicin for febrile neutropenia in the context of relapsed Hodgkin lymphoma. Eighteen days after commencing chemotherapy for relapsed Hodgkin lymphoma the patient presented to hospital with fevers, hypotension and neutropenia. The patient was commenced on piperacillin, tazobactam and gentamicin. Within 24 h the patient developed marked hypokalaemia and hypophosphataemia requiring intravenous replacement therapy. There was proteinuria, glycosuria and evidence of marked urinary electrolyte wasting, consistent with acute proximal tubular dysfunction. Eleven days after the gentamicin was stopped the serum biochemistry normalised. The urinary electrolyte wasting and proteinuria had improved, and the glycosuria had resolved. CONCLUSION: This is the first case report to describe acute renal proximal tubulopathy in an HIV-infected patient treated with TAF and gentamicin. As the number of patients prescribed TAF outside the clinical trial setting increases, so too does the potential for previously unreported drug interactions and adverse events. Clinicians need to be aware of potential unreported adverse drug reactions as the use of TAF becomes increasingly common in clinical practice.

[Urinary tract infections in patients with type 2 diabetes mellitus with pharmacological glucosuria].

Selective inhibitors of sodium-glucose cotransporter belong to a new class of drugs for the treatment of type 2 diabetes mellitus. The mechanism of their action is based on insulin-independent reduction of glucose reabsorption in the proximal renal tubules, which leads to stimulation of its excretion in the urine and, accordingly, to a decrease in the concentration of glucose in the blood plasma. Drugs of this group demonstrate effectiveness in the treatment of type 2 diabetes, but their use may be associated with an increased frequency of urinary tract infections. Pharmacological glucosuria, which leads to a decrease in the concentration of glucose in the blood, creates the preconditions for the occurrence of urinary tract infections. Urinary tract and genital infections are the most common adverse events associated with the use of sodium-glucose cotransporter inhibitors. In the presented literature review for 20162019, the relationship between urinary tract infections in patients with type 2 diabetes mellitus and therapy with sodium-glucose cotransporter inhibitors was analyzed.

The clinical and pathological features of adefovir dipivoxil-related renal impairment
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AIMS: To investigate the clinicopathological features and outcomes of adefovir dipivoxil (ADV)-related renal impairment in Chinese patients. MATERIALS AND METHODS: Clinical, pathological, and follow-up data from 15 patients with ADV-related renal impairment were studied. Proximal renal tubular dysfunction (PRTD) was defined by the presence of at least two of the following four abnormalities: hypophosphatemia, hypouricemia, nondiabetic glucosuria, and proteinuria. RESULTS: All patients were treated for 3 - 15 (mean 6.7) years with daily ADV of 10 mg. Renal impairment manifested as PRTD (12, 80%), elevated serum creatinine (12, 80%), and hematuria (2, 13.3%). Mild to moderate tubulointerstitial injury primarily affecting the proximal tubules by light microscopy, and enlarged, dysmorphic mitochondria with loss and disorientation of cristae by electron microscope were identified in all of our cases. Four patients had pathological evidence of IgA nephropathy. The phosphorus, serum uric acid, and creatinine levels were normalized after ADV cessation in 66.7% (8/12) of affected patients, 27.3% (3/11) of affected patients, and 25% (3/12) of affected patients, respectively; proteinuria was eliminated in 7 of 13 affected patients (53.8%); and glucosuria and hematuria both disappeared in all affected patients. These abnormalities had hardly any recovery, and even aggravated with new-onset glucosuria, new-onset hematuria in 3 patients who replaced ADV with tenofovir. CONCLUSION: Nephrotoxicity developed in patients undergoing long-term ADV treatment and was partially reversible after drug cessation. Tubulointerstitial lesions and heteromorphic mitochondria were the predominant pathological changes. Patients with ADV-induced renal impairment should replace ADV with other antiviral agents other than tenofovir.
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Amitraz: A Perpetual Silent Menace Among Children in Developing Countries-A Case Report.

Amitraz is an acaricide and insecticide used to treat ticks, which infest domestic animals in developing countries. Because of its widespread use, it is one of the common poisons unintentionally consumed by infants and children when left unsupervised. A 3-year-old boy was brought with unintentional consumption of Amitraz. On examination, he was found to be progressively drowsy, with an irregular pulse, bradycardia, and hypotension. He was treated with atropine, intravenous fluids, and dopamine infusion; hemodynamic stability was achieved within 36 hours after ingestion. Amitraz is an unusual but deadly poison unintentionally consumed by children. It can be suspected in the setting of rural households in developing countries having pets. There is no antidote available, and treatment is mainly supportive.

Effect of a SGLT2 inhibitor on the systemic and intrarenal renin-angiotensin system in subtotally nephrectomized rats.

We aimed to examine the effects of a sodium glucose co-transporter 2 (SGLT2) inhibitor on systemic and intrarenal renin-angiotensin system (RAS) in subtotally nephrectomized non-diabetic rats, a model of chronic kidney disease (CKD). Oral administration of the selective SGLT2 inhibitor, TA-1887 (10 mg/kg/day), for 10 weeks induced glycosuria. However, plasma renin activity, plasma angiotensinogen levels, kidney angiotensin II contents and renal injury were not significantly affected by TA-1887. These data indicate that chronic treatment with an SGLT2 inhibitor does not activate the systemic and intrarenal RAS in subjects with non-diabetic CKD.

The role of SGLT2 inhibitors in managing type 2 diabetes.

The sodium glucose cotransporter 2 (SGLT2) inhibitors canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin represent a novel class of medications to manage type 2 diabetes through urinary excretion of glucose. These drugs block glucose reabsorption by the kidneys to increase glucosuria. These drugs provide hemoglobin A1C reduction, promote weight loss, and remain hypoglycemic-neutral when not used in combination with insulin or secretagogues. Canagliflozin and empagliflozin have shown cardiovascular benefit. The potential to reduce the risk of cardiovascular death in patients with type 2 diabetes, along with the benefit of weight reduction, makes these new agents useful tools for the primary care provider.

Effects of dapagliflozin on insulin-requirement, glucose excretion and ß-hydroxybutyrate levels are not related to baseline HbA1c in youth with type 1 diabetes.

Youth with type 1 diabetes (T1D) infrequently achieve HbA1c targets. Therefore, this placebo-controlled, randomized, crossover study was set up to assess the safety, effect and pharmacokinetics of a single dose of 10 mg dapagliflozin (DAPA) as add-on to insulin in relationship to HbA1c in youth. A total of 33 youths (14 males, median age 16 years, diabetes duration 8 years) were included and stratified into 3 baseline HbA1c categories (<7.5%, 7.5%-9.0% or >9.0; n = 11 each). During the study period of 24 hours, intravenous insulin administration and glucose-infusion kept blood glucose levels at 160 to 220 mg/dL. DAPA reduced mean insulin dose by 13.6% ( P < .0001 by ANOVA) and increased urinary glucose excretion by 610% (143.4 vs 22.4 g/24 h; P < .0001), both irrespective of baseline HbA1c. Six independent episodes in 6 patients with plasma ß-hydroxybutyrate levels between ≥0.6 and <1.0 mmol/L were observed after liquid meal challenges, 5 episodes in the DAPA group and 1 in the placebo group. This study provides a proof-of-concept, irrespective of preexisting HbA1c levels, for adjunct SGLT2-inhibitor therapy in the paediatric age group by lowering insulin dose and increasing glucose excretion.

SGLT2 Inhibitors: Glucotoxicity and Tumorigenesis Downstream the Renal Proximal Tubule?

At present, diabetes mellitus is the main cause of end-stage renal disease. Effective glycaemic management is the most powerful tool to delay the establishment of diabetic complications, such as diabetic kidney disease. Together with reducing blood glucose levels, new anti-diabetic agents are expected not only to control the progression but also to restore known defects of the diabetic kidney. Sodium-glucose co-transporter 2 (SGLT2) inhibitors are promising anti-diabetic agents that reduce hyperglycaemia by impairing glucose reabsorption in proximal tubule of the kidney and increasing glucosuria. SGLT2 inhibitors have shown to reduce glucotoxicity in isolated proximal tubule cells and also to attenuate expression of markers of overall kidney damage in experimental animal models of diabetes, but the actual renoprotective effect for downstream nephron segments is still unknown and deserves further attention. Here, we briefly discuss possible undesired effects of enhanced glucosuria and albuminuria in nephron segments beyond the proximal tubule after SGLT2 inhibitor treatment, offering new lines of research to further understand the renoprotective action of these anti-diabetic agents. Strategies blocking glucose reabsorption by renal proximal tubule epithelial cells (RPTEC) may be protective for RPTEC, but downstream nephron segments will still be exposed to high glucose and albumin levels through the luminal face. The actual effect of constant enhanced glucosuria over distal nephron segments remains to be established. J. Cell. Physiol. 231: 1635-1637, 2016. © 2015 Wiley Periodicals, Inc.

Yield of Urinalysis Screening in Pediatric Cancer Survivors.

BACKGROUND: The Children's Oncology Group (COG) publishes consensus guidelines with screening recommendations for early identification of treatment-related morbidities among childhood cancer survivors. We sought to estimate the yield of recommended yearly urinalysis screening for genitourinary complications as per Version 3.0 of the COG Long-Term Follow-Up Guidelines and identify possible risk factors for abnormal screening in a survivor population. PROCEDURE: A database of pediatric cancer survivors evaluated between January 2008 and March 2012 at Children's Healthcare of Atlanta was queried for survivors at risk for genitourinary late effects. The frequency of abnormal urinalyses (protein ≥1+ and/or presence of glucose and/or ≥5 red blood cells per high power field) was estimated. Risk factors associated with abnormal screening were identified. RESULTS: Chart review identified 773 survivors (57% male; 67% Caucasian; 60% leukemia/lymphoma survivors; mean age at diagnosis, 5.7 years [range: birth to 17.7 years]; time from diagnosis to initial screening, 7.6 years [range: 2.3 to 21.5 years]) who underwent urinalysis. Abnormal results were found in 78 (5.3%) of 1,484 total urinalyses. Multivariable analysis revealed higher dose ifosfamide (odds ratio [OR] = 6.8, 95% confidence interval [CI] 2.9-16.0) and total body irradiation (TBI, OR = 3.0, 95% CI 1.0-8.4) as significant risk factors for abnormal initial urinalysis screening. CONCLUSIONS: Pediatric cancer survivors exposed to higher dose ifosfamide or TBI may be at higher risk of abnormal findings on urinalysis screening. Targeted screening of these higher risk patients should be considered.

A new dammarane saponin and other triterpenoids from Siolmatra brasiliensis and evaluation of the antidiabetic activity of its extract.

Context Siolmatra brasiliensis (Cogn.) Baill (Cucurbitaceae) is a climbing plant widely used for the treatment of diabetes mellitus symptoms. Objective This work evaluates the antidiabetic activity of an extract of S. brasiliensis in streptozotocin-diabetic rats and promotes the phytochemical investigation to isolate the major compounds of the same extract. Materials and methods Male Wistar rats were divided into normal (N) and diabetic rats (DC) treated with water; diabetic rats treated with 3U insulin (DI) or with 250 (DSb250) or 500 mg/kg (DSb500) of hydroalcoholic extract of the stalks of S. brasiliensis, via oral gavage, for 21 days. Physiological and biochemical parameters classically altered in diabetes were monitored. The triterpenoids were isolated from the ethyl acetate fraction under silica gel column chromatography and Sephadex-LH20 methods and their structures were determined by NMR, HR-ESI-MS and DC analysis. Results When compared with DC, DSb250 rats showed a reduction in the hyperglycemia (DC: 26.46 ± 0.69 versus DSb250: 19.67 ± 1.06 mmol/L) and glycosuria (DC: 43.02 ± 3.19 versus DSb250: 28.46 ± 2.14 mmol/24 h) and increase in hepatic glycogen (DC: 14.44 ± 1.26 versus DSb250: 22.08 ± 4.26 mg/g). Three known cucurbitacins were isolated from a hydroalcoholic extract of S. brasiliensis, i.e., cayaponosides A1, B4, D, and a new dammarane saponin 3-O-ß-d-gentiobiosyl-26-O-ß-d-glucopyranosyl-20-hydroxydammar-24-ene. The structures of these compounds were elucidated by spectral data analysis of the natural products and their acetyl derivatives. Discussion and conclusion The known cucurbitacins and/or the new identified saponin may be related with the antidiabetic activity of S. brasiliensis.

Phenotype standardization for drug-induced kidney disease.

Drug-induced kidney disease is a frequent cause of renal dysfunction; however, there are no standards to identify and characterize the spectrum of these disorders. We convened a panel of international, adult and pediatric, nephrologists and pharmacists to develop standardized phenotypes for drug-induced kidney disease as part of the phenotype standardization project initiated by the International Serious Adverse Events Consortium. We propose four phenotypes of drug-induced kidney disease based on clinical presentation: acute kidney injury, glomerular, tubular, and nephrolithiasis, along with the primary and secondary clinical criteria to support the phenotype definition, and a time course based on the KDIGO/AKIN definitions of acute kidney injury, acute kidney disease, and chronic kidney disease. Establishing causality in drug-induced kidney disease is challenging and requires knowledge of the biological plausibility for the specific drug, mechanism of injury, time course, and assessment of competing risk factors. These phenotypes provide a consistent framework for clinicians, investigators, industry, and regulatory agencies to evaluate drug nephrotoxicity across various settings. We believe that this is the first step to recognizing drug-induced kidney disease and developing strategies to prevent and manage this condition.

A novel and selective sodium-glucose cotransporter-2 inhibitor, tofogliflozin, improves glycaemic control and lowers body weight in patients with type 2 diabetes mellitus.

AIM: To assess the efficacy, safety and tolerability of different doses of tofogliflozin, a novel, highly selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, in patients with type 2 diabetes mellitus (T2DM). METHODS: In a 12-week, multicentre, multinational, randomized, double-blind, parallel-group, placebo-controlled, dose-finding study, patients with inadequate glycaemic control from diet and exercise alone, or from diet and exercise plus a stable dose of metformin, were randomized to one of five doses of tofogliflozin (2.5, 5, 10, 20, or 40 mg) or placebo. The primary efficacy endpoint was absolute change at week 12 from baseline in glycated haemoglobin (HbA1c), minus the change in the placebo group. RESULTS: Statistically significant dose-dependent reductions in HbA1c were shown in all treated groups except the 2.5-mg dose group, with a maximum reduction of 0.56% (placebo-subtracted) at the 40-mg dose, along with increased urinary glucose excretion. Metformin treatment had no substantial influence on tofogliflozin efficacy. Dose-dependent reductions in fasting plasma glucose and body weight were observed, and glucose intolerance was improved, with a trend towards blood pressure reduction. Slight increases were observed for mean ketone bodies with no abnormal change in ketone body ratio. No deaths or treatment-related serious adverse events were reported. The incidence of adverse events was similar in the placebo (37.9%) to that in the tofogliflozin group (35.9-46.3%). Withdrawal because of adverse events was rare (≤2 patients per treatment group), with similar rates of withdrawal in the placebo and tofogliflozin groups. CONCLUSIONS: A once-daily dose of tofogliflozin for 12 weeks was an effective, safe and well-tolerated treatment for T2DM.

Dapagliflozin twice daily or once daily: effect on pharmacokinetics and urinary glucose excretion in healthy subjects.

The primary objective of this single-centre, open-label crossover study (NCT01072578) was to assess the effect of dapagliflozin on the amount of glucose in the blood and urine in healthy volunteers when dapagliflozin was administered once a day (10 mg) versus twice a day (5 mg every 12 h) after 5 days of dosing. At steady state, the AUC(ss)0₋24 (area under the dapagliflozin curve (0-24 hours) at steady state), C(ss,av) (average concentration at steady state) between dapagliflozin 5 mg twice daily and 10 mg once daily were similar AUC(ss)0₋24 [5 mg bid, (458.0 (28.7)) and 10 mg qd, (470.0 (28.5))] and C(ss,av) [5 mg bid 18.8 (28.9)) and 10 mg qd, (19.6(28.5))], but minimum and maximum plasma levels of dapagliflozin differed significantly. Percent inhibition of renal glucose reabsorption (%IRGRA) and total urinary glucose excretion over 24 h were similar for both doses. The relationship between the mean dapagliflozin concentration and %IRGRA and the total urinary glucose excreted was well described by a maximum effect model. The results indicate that dapagliflozin may be used for either once daily or twice daily administration.

Characterization of Batracylin-induced Renal and Bladder Toxicity in Rats.

Batracylin (NSC-320846) is a dual inhibitor of DNA topoisomerases I and II. Batracylin advanced as an anticancer agent to Phase I clinical trials where dose limiting hemorrhagic cystitis (bladder inflammation and bleeding) was observed. To further investigate batracylin's mechanism of toxicity, studies were conducted in Fischer 344 rats. Once daily oral administration of 16 or 32 mg/kg batracylin to rats for 4 days caused overt toxicity. Abnormal clinical observations and adverse effects on clinical pathology, urinalysis, and histology indicated acute renal damage and urothelial damage and bone marrow dysfunction. Scanning electron microscopy revealed sloughing of the superficial and intermediate urothelial layers. DNA damage was evident in kidney and bone marrow as indicated by histone γ-H2AX immunofluorescence. After a single oral administration of 16 or 32 mg/kg, the majority of batracylin was converted to N-acetylbatracylin (NAB) with a half-life of 4 hr to 11 hr. Mesna (Mesnex™), a drug known to reduce the incidence of hemorrhagic cystitis induced by ifosfamide or cyclophosphamide, was administered to rats prior to batracylin, but did not alleviate batracylin-induced bladder and renal toxicity. These findings suggest that batracylin results in DNA damage-based mechanisms of toxicity and not an acrolein-based mechanism of toxicity as occurs after ifosfamide or cyclophosphamide administration.