Hepatotoxic combination effects of three azole fungicides in a broad dose range.

Single active substances of pesticides are thoroughly examined for their toxicity before approval. In this context, the liver is frequently found to be the main target organ. Since consumers are generally exposed to multiple residues of different active substances via the diet, it is important to analyse combinations of active substances for potential mixture effects. For the (tri-)azoles, a group of agricultural fungicides and antifungal drugs, combination effects on the liver are likely because of a similar mode of action. Hepatotoxic effects of mixtures of two triazoles (cyproconazole and epoxiconazole) and an imidazole (prochloraz) were investigated in a 28-day feeding study in rats at three dose levels ranging from a typical toxicological reference value to a clear effect dose. Test parameters included organ weights, clinical chemistry, histopathology and morphometry. In addition, molecular parameters were investigated by means of pathway-focused gene expression arrays, quantitative real-time PCR and enzyme activity assays. Effects were compared to those caused by the individual substances as observed at the same dose levels in a previous study. Mixture effects were substantiated by increases in relative and absolute liver weights, histopathological findings and alterations in clinical chemistry parameters at the top dose level. On the molecular level also at lower dose levels, additive effects could be observed for the induction of several cytochrome P 450 enzymes (Cyp1a1, Cyp2b1, Cyp3a2), transporters (Abcb1a, Abcc3) and of genes encoding for enzymes involved in fatty acid or phospholipid metabolism (Ppargc1a, Sc4 mol). In most cases, treatment with mixtures caused a more pronounced effect as compared to the individual substances. However, the assumption of dose additivity was in general sufficiently conservative to cover mixture effects observed under the conditions of the present study.

Introduction of biosimilar insulins in Europe.

Regulatory approval of the first biosimilar insulin in Europe, LY2963016 insulin glargine (Abasaglar® ), in 2014 expanded the treatment options available to people with diabetes. As biosimilar insulin products come to market, it is important to recognize that insulin products are biologicals manufactured through complex biotechnology processes, and thus biosimilar insulins cannot be considered identical to their reference products. Strict regulatory guidelines adopted by authorities in Europe, the USA and some other countries help to ensure that efficacy and safety profiles of biosimilar insulins are not meaningfully different from those of the reference products, preventing entry of biological compounds not meeting quality standards and potentially affecting people's glycaemic outcomes. This review explains the concept of biosimilar medicines and outlines regulatory requirements for registration of biosimilar insulins in Europe, which is illustrated by the successful development of LY2963016 insulin glargine and MK-1293 insulin glargine (Lusduna® ). Preclinical and clinical comparative studies of the biosimilar insulin glargine programmes include in vitro bioassays for insulin and insulin-like growth factor 1 receptor binding, assessment of in vitro biological activity, evaluation of pharmacokinetic/pharmacodynamic profiles in phase I studies and assessment of long-term safety and efficacy in phase III studies. The emergence of biosimilar insulins may help broaden access to modern insulins, increase individualized treatment options and reduce costs of insulin therapy.

Pharmacokinetics and pharmacodynamics of various glucagon dosages at different blood glucose levels.

AIMS: To evaluate the pharmacokinetics and pharmacodynamics of different doses of glucagon administered subcutaneously (s.c.) at different blood glucose levels. METHODS: This study was an open-label, randomized, three-period, cross-over experiment in 6 patients with type 1 diabetes. During each of the three periods, different blood glucose levels were established in four consecutive steps (8, 6, 4 and 2.8 mmol/l) and glucagon was given at each blood glucose level in doses from 0.11 to 0.44 mg and 0.33, 0.66 and 1 mg at the lowest glucose concentration. RESULTS: Maximum glucagon concentration and area under the curve increased with increasing glucagon dose. Maximum glucagon concentration was reached after 10-20 min. Glucagon raised blood glucose in a dose-dependent manner at different baseline blood glucose levels. The median glucose excursion ranged from 2.6 to 6.2 mmol/l. Time to maximum glucose concentration was dose-dependent for the glucagon doses at 2.8 mmol/l, with median values from 40 to 80 min. CONCLUSIONS: Glucagon administered s.c. produces a stable pharmacokinetic and pharmacodynamic response at lower doses than the usual rescue dose and across a range of hypo- to hyperglycaemic blood glucose levels. This supports the use of small glucagon doses in the artificial pancreas to correct and prevent hypoglycaemia.

Aleglitazar, a dual peroxisome proliferator-activated receptor-α/γ agonist, improves insulin sensitivity, glucose control and lipid levels in people with type 2 diabetes: findings from a randomized, double-blind trial.

The present single-centre, randomized, double-blind, placebo-controlled phase II study investigated the effect of the balanced dual peroxisome proliferator-activated receptor-α/γ agonist aleglitazar on whole-body and liver insulin sensitivity, ß-cell function and other components of cardiometabolic syndrome after 16 weeks of treatment in patients with type 2 diabetes inadequately controlled with metformin monotherapy who received once-daily 150 µg aleglitazar or matching placebo as add-on therapy to metformin. Baseline and 16-week assessments included a two-step hyperinsulinaemic-euglycaemic clamp, followed by a hyperglycaemic clamp, as well as evaluation of glycated haemoglobin (HbA1c), lipids and safety variables. The primary endpoint was change in whole-body insulin sensitivity (M-value) from baseline compared with placebo, derived from the second clamp step. M-value improved significantly from baseline with aleglitazar (n = 16) compared with placebo (n = 24; p = 0.05 for difference between arms). We found statistically significant treatment differences with aleglitazar versus placebo in fasting hepatic insulin resistance index (p = 0.01), and in total glucose disposal (p = 0.03) at the second insulin infusion step. Aleglitazar treatment resulted in significant improvements in HbA1c and lipids and was well tolerated.

Effects of dextromethorphan as add-on to sitagliptin on blood glucose and serum insulin concentrations in individuals with type 2 diabetes mellitus: a randomized, placebo-controlled, double-blinded, multiple crossover, single-dose clinical trial.

In this clinical trial, we investigated the blood glucose (BG)-lowering effects of 30, 60 and 90 mg dextromethorphan (DXM) as well as 100 mg sitagliptin alone versus combinations of DXM and sitagliptin during an oral glucose tolerance test (OGTT) in 20 men with T2DM. The combination of 60 mg DXM plus 100 mg sitagliptin was observed to have the strongest effect in the OGTT. It lowered maximum BG concentrations and increased the baseline-adjusted area under the curve for serum insulin concentrations in the first 30 min of the OGTT (mean ± standard deviation 240 ± 47 mg/dl and 8.1 ± 6.1 mU/l/h, respectively) to a significantly larger extent than did 100 mg sitagliptin alone (254 ± 50 mg/dl and 5.8 ± 2.5 mU/l/h, respectively; p < 0.05) and placebo (272 ± 49 mg/dl and 3.9 ± 3.0 mU/l/h, respectively; p < 0.001). All study drugs were well tolerated, alone and in combination, without serious adverse events or hypoglycaemia. Long-term clinical trials are now warranted to investigate the potential of the combination of 30 or 60 mg DXM and dipeptidyl peptidase-4 inhibitors in the treatment of individuals with T2DM, in particular as preclinical studies have identified the ß-cell protective properties of DXM.

Similar risk of exercise-related hypoglycaemia for insulin degludec to that for insulin glargine in patients with type 1 diabetes: a randomized cross-over trial.

We compared changes in blood glucose (BG) and risk of hypoglycaemia during and after exercise in 40 patients with type 1 diabetes (T1D) treated with insulin degludec (IDeg) or insulin glargine (IGlar) in a randomized, open-label, two-period, crossover trial. After individual titration and a steady-state period, patients performed 30 min of moderate-intensity cycle ergometer exercise (65% peak rate of oxygen uptake). BG, counter-regulatory hormones and hypoglycaemic episodes were measured frequently during and for 24 h after exercise. BG changes during exercise were similar with IDeg and IGlar [estimated treatment difference (ETD) for maximum BG decrease: 0.14 mmol/l; 95% confidence interval (CI) -0.15, 0.42; p = 0.34], as was mean BG (ETD -0.16 mmol/l; 95% CI -0.36, 0.05; p = 0.13). No hypoglycaemic episodes occurred during exercise. Post-exercise mean BG, counter-regulatory hormone response and number of hypoglycaemic episodes in 24 h after starting exercise were similar with IDeg (18 events in 13 patients) and IGlar (23 events in 15 patients). This clinical trial showed that, in patients with T1D treated with a basal-bolus regimen, the risk of hypoglycaemia induced by moderate-intensity exercise was low with IDeg and similar to that with IGlar.

Safety, pharmacokinetics and pharmacodynamics of BI 135585, a selective 11ß-hydroxysteroid dehydrogenase-1 (HSD1) inhibitor in humans: liver and adipose tissue 11ß-HSD1 inhibition after acute and multiple administrations over 2 weeks.

AIMS: To assess the safety and pharmacokinetic and pharmacodynamic characteristics of BI 135585, a selective 11ß-hydroxysteroid dehydrogenase-1 (11ß-HSD1) inhibitor, after single- and repeated-dose administration. METHODS: The single-dose study included open-label administration of 200 mg BI 135585 in healthy volunteers, while in the multiple-dose study, we carried out randomized, double-blind administration of 5-200 mg BI 135585 or placebo once daily over 14 days in patients with type 2 diabetes (T2DM). Assessments included 11ß-HSD1 inhibition in the liver (urinary tetrahydrocortisol (THF)/tetrahydrocotisone (THE) ratio) and in subcutaneous adipose tissue (AT) ex vivo and determination of hypothalamus-pituitary-adrenal (HPA) axis hormone levels. RESULTS: No major safety issues occurred with BI 135585 administration. The HPA axis was mildly activated with slightly increased, but still normal adrenocorticotropic hormone levels, increased total urinary corticoid excretion but unchanged plasma cortisol levels. After multiple doses of 5-200 mg BI 135585, exposure (area under the curve) increased dose-proportionally and half-life was 55-65 h. The urinary THF/THE ratio decreased, indicating liver 11ß-HSD1 inhibition. Median 11ß-HSD1 enzyme inhibition in the AT reached 90% after a single dose of BI 135585, but was low (31% or lower) after 14 days of continuous treatment. CONCLUSIONS: BI 135585 was safe and well tolerated over 14 days and can be dosed once daily. Future studies are required to clarify the therapeutic potential of BI 135585 in view of its effects on 11ß-HSD1 inhibition in AT after single and multiple doses. Enzyme inhibition in the AT was not adequately predicted by the urinary THF/THE ratio.

Faster-acting insulin aspart: earlier onset of appearance and greater early pharmacokinetic and pharmacodynamic effects than insulin aspart.

AIMS: To evaluate the pharmacokinetics and pharmacodynamics of faster-acting insulin aspart and insulin aspart in a randomized, single-centre, double-blind study. METHODS: Fifty-two patients with type 1 diabetes (mean age 40.3 years) received faster-acting insulin aspart, insulin aspart, or another faster aspart formulation (not selected for further development), each as a single 0.2 U/kg subcutaneous dose, under glucose-clamp conditions, in a three-way crossover design (3-12 days washout between dosing). RESULTS: Faster-acting insulin aspart had a faster onset of exposure compared with insulin aspart, shown by a 57% earlier onset of appearance [4.9 vs 11.2 min; ratio 0.43, 95% confidence interval (CI) 0.36; 0.51], a 35% earlier time to reach 50% maximum concentration (20.7 vs 31.6 min; ratio 0.65, 95% CI 0.59; 0.72) and a greater early exposure within 90 min after dosing. The greatest difference occurred during the first 15 min, when area under the serum insulin aspart curve was 4.5-fold greater with faster-acting insulin aspart than with insulin aspart. Both treatments had a similar time to maximum concentration, total exposure and maximum concentration. Faster-acting insulin aspart had a significantly greater glucose-lowering effect within 90 min after dosing [largest difference: area under the curve for the glucose infusion rate (AUC(GIR), 0-30 min) ratio 1.48, 95% CI 1.13; 2.02] and 17% earlier time to reach 50% maximum glucose infusion rate (38.3 vs 46.1 min; ratio 0.83, 95% CI 0.73; 0.94). The primary endpoint (AUC(GIR, 0-2 h)) was 10% greater for faster-acting insulin aspart, but did not reach statistical significance (ratio 1.10, 95% CI 1.00; 1.22). Both treatments had similar total and maximum glucose-lowering effects, indicating similar overall potency. CONCLUSIONS: Faster-acting insulin aspart was found to have earlier onset and higher early exposure than insulin aspart, and a greater early glucose-lowering effect, with similar potency.

Insulin degludec/insulin aspart produces a dose-proportional glucose-lowering effect in subjects with type 1 diabetes mellitus.

AIMS: To evaluate the pharmacodynamic dose-response relationship of insulin degludec/insulin aspart (IDegAsp), a novel, soluble co-formulation of the ultra-long-acting basal insulin, insulin degludec (IDeg), with the rapid-acting prandial insulin (IAsp), across different doses in patients with type 1 diabetes (T1DM). METHODS: This was a randomized, single-centre, double-blind, four-period, incomplete block, crossover trial. A cohort of 33 people with T1DM received single doses (0.4, 0.6 or 0.8 U/kg) of IDegAsp or the comparator, biphasic insulin aspart 30, in a randomized sequence of four treatment periods, each separated by a washout of 13-21 days. Pharmacodynamic response was assessed using a 26-h euglycaemic glucose clamp, with blood glucose stabilized at a target of 5.5 mmol/l (100 mg/dl). RESULTS: A rapid onset of action and a distinct peak attributable to IAsp was observed in the glucose infusion rate (GIR) profile, followed by a separate, flat and stable basal glucose-lowering effect attributable to the IDeg component. The mean area under the GIR curve over 24 h (AUC(GIR,0-24 h)), and the mean maximum GIR (GIR(max)) increased with increasing dose level of IDegAsp. A dose-response relationship for IDegAsp was demonstrated for AUC(GIR,0-24 h) and GIR(max), indicating dose proportionality. A dose-concentration relationship was also observed for both the basal and bolus components of IDegAsp. CONCLUSIONS: IDegAsp has a clear dose-response relationship, indicating the clinical potential for straightforward titration according to individual patient needs.

Single-dose new insulin glargine 300 U/ml provides prolonged, stable glycaemic control in Japanese and European people with type 1 diabetes.

AIMS: Two single-dose studies were conducted in Japan and Europe to compare the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of new insulin glargine 300 U/ml (Gla-300) and insulin glargine 100 U/ml (Gla-100) in people with type 1 diabetes mellitus. METHODS: In two double-blind, randomized, crossover studies, 18 Japanese participants (aged 20-65 years) and 24 European participants (aged 18-65 years) with glycated haemoglobin levels ≤9.0% (≤75 mmol/mol) received single subcutaneous doses of Gla-300, 0.4, 0.6 and 0.9 U/kg (0.9 U/kg in the European study only), and Gla-100, 0.4 U/kg. A 36-h euglycaemic clamp procedure was performed after each dosing. RESULTS: The serum insulin glargine concentration (INS) and glucose infusion rate (GIR) developed more gradually into more constant and prolonged profiles with Gla-300 than with Gla-100. In support of this, the times to 50% of glargine exposure and insulin activity were longer for all Gla-300 doses than for Gla-100 during the 36-h clamp period, indicating a more evenly distributed exposure and metabolic effect beyond 24 h. Exposure to insulin glargine and glucose utilization were lower with the 0.4 and 0.6 U/ml Gla-300 doses in both studies compared with the 0.4 U/ml Gla-100 dose. Glucose-lowering activity was detected for up to 36 h with all doses of Gla-300. CONCLUSIONS: Single-dose injections of Gla-300 present more constant and prolonged PK and PD profiles compared with Gla-100, maintaining blood glucose control for up to 36 h in euglycaemic clamp settings in Japanese and European participants with type 1 diabetes.

Hepatotoxic effects of (tri)azole fungicides in a broad dose range.

The toxicological relevance of effects observed at molecular stage, which occur at dose levels well below classical no-observed adverse effect levels is currently subject to controversial scientific debate. While the importance of molecular effects for the identification of a mode of action or an adverse outcome pathway is undisputed, their impact for other regulatory purposes remains uncertain. Here, we report the results of a 28-day rat-feeding study including three widely used hepatotoxic (tri)azole fungicides (cyproconazole, epoxiconazole and prochloraz) administered individually at five dose levels, ranging from slightly above the reference values to a clear toxic effect dose. Parameters analysed included pathology, histopathology, clinical chemistry and particularly effects on the molecular level. Since azole fungicides are considered to cause liver toxicity by a mechanism involving the constitutive androstane receptor (CAR), a known CAR activator (phenobarbital, PB) was administered to investigate potential similarities between triazoles and PB-mediated liver toxicity by pathway-focused gene expression analysis. Our results show an increase in liver weights and additionally histopathological changes (hepatocellular hypertrophy) for all substances at the top dose levels. The effects on liver weight were most pronounced for cyproconazole by which also the animals receiving the next lower dose were affected. In addition, vacuolisation of hepatocytes was observed at the top dose level. No such findings were obtained with any substance at lower doses to which consumers and operators might be exposed to. In contrast, the expression of sensitive marker genes (like some cytochrome-P-450 isoforms) was significantly affected also at the lower dose levels. While some of these changes, like the induction of genes related to fatty acid and phospholipid metabolism (e.g. Fasn, Fat/Cd36, Ppargc1a) or xenobiotic metabolism (Cyp1a1, Cyp2b1, Cyp3a2), could be associated with high dose effects like hepatocellular vacuolisation or hypertrophy, a histopathological correlate was lacking for others.

Application of omics data in regulatory toxicology: report of an international BfR expert workshop.

Advances in omics techniques and molecular toxicology are necessary to provide new perspectives for regulatory toxicology. By the application of modern molecular techniques, more mechanistic information should be gained to support standard toxicity studies and to contribute to a reduction and refinement of animal experiments required for certain regulatory purposes. The relevance and applicability of data obtained by omics methods to regulatory purposes such as grouping of chemicals, mode of action analysis or classification and labelling needs further improvement, defined validation and cautious expert judgment. Based on the results of an international expert workshop organized 2014 by the Federal Institute for Risk Assessment in Berlin, this paper is aimed to provide a critical overview of the regulatory relevance and reliability of omics methods, basic requirements on data quality and validation, as well as regulatory criteria to decide which effects observed by omics methods should be considered adverse or non-adverse. As a way forward, it was concluded that the inclusion of omics data can facilitate a more flexible approach for regulatory risk assessment and may help to reduce or refine animal testing.

Steady-state pharmacokinetics and glucodynamics of the novel, long-acting basal insulin LY2605541 dosed once-daily in patients with type 2 diabetes mellitus.

AIMS: To assess the pharmacokinetics (PK) and glucodynamics (GD) of LY2605541 in patients with type 2 diabetes mellitus. METHODS: This parallel-group, open-label, dose-escalation study examined the PK and GD of basal insulin LY2605541 after single and multiple-dose administration. Fixed doses of LY2605541 (0.33-1.00 U/kg) were given once-daily (QD) for 14 days to insulin-treated patients with type 2 diabetes. A 24-h euglycaemic glucose clamp was conducted on days 1 and 14. RESULTS: PK steady state was achieved within 7-10 days and the peak-to-trough fluctuation was <2, translating to a nearly 'peakless' glucose infusion rate at steady state and with a duration of action of at least 24 h. Across dose levels t1/2 ranged from 44.7 to 75.5 h (~2-3 days). As steady state was achieved, there were dose-dependent reductions in the prandial insulin dose and in fasting blood glucose, which decreased to 60-100 mg/dl across dose levels. Within-patient variability was <14 and <26% for the area under the concentration versus time curve (AUC) of the 8-point blood glucose profile and fasting blood glucose, respectively. The nocturnal glucose control between 03:00 and 09:00 hours was relatively unchanged. Mild hypoglycaemia was the most common adverse event. CONCLUSIONS: In this Phase I study of fixed LY2605541 doses without titration, LY2605541 was well-tolerated and demonstrated a flat PK and GD profile accompanied by glucose normalization, prandial insulin dose reduction and no severe hypoglycaemia.

Impact of injection speed and volume on perceived pain during subcutaneous injections into the abdomen and thigh: a single-centre, randomized controlled trial.

AIM: The aim of this study was to assess pain associated with subcutaneous injection into the abdomen and thigh of different combinations of injection speeds and volumes. METHODS: The study was a single-centre, one-visit, double-blinded, randomized controlled trial in 82 adults with type 1 or type 2 diabetes receiving daily injections of insulin or glucagon-like peptide-1 (GLP-1) agonists. Participants received 17 subcutaneous injections (12 in abdomen, 5 in thigh) of saline at different injection speeds (150, 300 and 450 µl/s), with different volumes (400, 800, 1200 and 1600 µl), and two needle insertions without any injection. Pain was evaluated on a 100-mm visual analogue scale (VAS) (0 mm no pain, 100 mm worst pain) and on a yes/no scale for pain acceptability. RESULTS: Injection speed had no impact on injection pain (p = 0.833). Injection of larger volumes caused significantly more pain [VAS least square mean differences 1600 vs. 400 µl, 7 · 2 mm (95% confidence interval - CI; 4.6-9.7; p < 0.0001); 1600 vs. 800 µl, 7.2 mm (4.4-10.0; p < 0.0001); 1200 vs. 400 µl, 3.5 mm (0.4-6.6; p = 0.025) and 1200 vs. 800 µl, 3.6 mm (0.4-6.7; p = 0.027)]. Significantly more pain occurred in the thigh versus the abdomen [9.0 mm (6.7-11.3; p < 0.0001)]. CONCLUSIONS: Injection speed had no effect on injection pain, whereas higher injection volumes caused more pain. The results of this study may be of value for guiding patients to use the appropriate injection site and technique to reduce their injection pain. Furthermore, these findings may have important implications for the development of new injection devices and drug formulations for clinical practice.

The dipeptidyl peptidase-4 inhibitor linagliptin lowers postprandial glucose and improves measures of ß-cell function in type 2 diabetes.

Progressive deterioration of pancreatic ß-cell function in patients with type 2 diabetes mellitus (T2DM) contributes to worsening of hyperglycaemia. To investigate the effects of the dipeptidyl peptidase-4 inhibitor linagliptin on ß-cell function parameters, a pooled analysis of six randomized, 24-week, placebo-controlled, phase 3 trials of 5 mg of linagliptin daily was performed in 2701 patients with T2DM (linagliptin, n = 1905; placebo, n = 796). At week 24, observed improvements in HbA1c, fasting plasma glucose, and 2-h postprandial glucose were significantly greater for linagliptin than placebo (all p < 0.0001). Homeostasis model assessment (HOMA)-%ß, as a surrogate marker of fasting ß-cell function, was significantly improved with linagliptin, and did not change with placebo (placebo-adjusted mean ± s.e. change for linagliptin: 16.5 ± 4.6 (mU/l)/(mmol/l); p = 0.0003). Further study is required to determine if the significant improvement in HOMA-%ß with linagliptin will translate into long-term improvements in ß-cell function.

Effect of the sodium glucose co-transporter 2 inhibitor canagliflozin on plasma volume in patients with type 2 diabetes mellitus.

AIM: To evaluate the effects of canagliflozin on plasma volume, urinary glucose excretion (UGE), fasting plasma glucose (FPG), glycated haemoglobin (HbA1c) and additional measures of fluid/electrolyte balance in patients with type 2 diabetes on background therapy with metformin and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. METHODS: Patients (N = 36) were randomized (1:1) to receive canagliflozin 300 mg or placebo for 12 weeks. Pharmacodynamic parameters were assessed at baseline and at weeks 1 and 12. RESULTS: Increased 24-h UGE was seen in the canagliflozin group compared with a reduction in the placebo group at both week 1 (91.8 vs. -2.4 g) and week 12 (82.6 vs. -0.4 g). Canagliflozin also reduced both FPG and HbA1c. Reductions in body weight and blood pressure were observed at weeks 1 and 12. Canagliflozin decreased plasma volume compared with an increase with placebo at week 1 (-5.4 vs. 4.3%; p = 0.02), but this was largely attenuated at week 12 (4.6 vs. 5.8%; p = 0.76). A modest numerical increase in urine volume was observed with canagliflozin at week 1 that was attenuated at week 12; other measures of volume status (i.e. blood urea nitrogen, serum creatinine and haematocrit) remained modestly increased with canagliflozin at week 12. CONCLUSION: Canagliflozin provided sustained effects on UGE and FPG over 12 weeks and a transient reduction in plasma volume that was largely attenuated by week 12.

Safety, efficacy and weight effect of two 11ß-HSD1 inhibitors in metformin-treated patients with type 2 diabetes.

AIMS: We assessed safety and efficacy of two selective 11ß-HSD1 inhibitors (RO5093151/RO-151 and RO5027383/RO-838) in this randomized, controlled study in metformin-treated patients with type 2 diabetes. METHODS: Patients either received placebo (N = 21), RO-151 BID 5 mg (N = 24) or 200 mg (N = 20) or RO-838 QD 50 mg (N = 21) or 200 mg (N = 24) for 28 days. Metabolic assessments comprising of nine-point plasma glucose profiles, oral glucose tolerance tests and determination of metabolic biomarkers including insulin, C-peptide, glucagon, HbA1c and lipids were done at baseline and end of treatment. RESULTS: Despite the short treatment duration, both RO-151 and RO-838 showed trends for improved HbA1c and consistent reductions in body weight (-0.86 to -1.67 kg) exceeding those observed with placebo (-0.28 kg, p = 0.019 for 200 mg RO-151 vs. placebo). Insulin sensitivity parameters (e.g. HOMA-IR and Matsuda-Index) improved non-significantly with 200 mg RO-151. Lipid parameters did not consistently improve with either compound, but RO-838 led to non-significant increases in triglycerides and VLDL-cholesterol versus placebo. Both compounds were well tolerated and showed inhibitory effects on 11ß-HSD1 activity based on urinary corticosteroid excretion. As reported for other 11ß-HSD1-inhibitors increased concentrations of ACTH and adrenal androgen precursors were found with RO-151, but not with RO-838. CONCLUSIONS: Slight metabolic improvements were seen, in particular with RO-151 high dose, however, the observed changes often did not reach statistical significance and were not clearly dose dependent. Studies of longer duration are needed to further investigate potential benefits and risks of these compounds.

Phosphorylation of human La protein at Ser 366 by casein kinase II contributes to hepatitis B virus replication and expression in vitro.

Human La protein (hLa) is a multifunctional RNA-binding protein involved in the regulation of hepatitis B virus (HBV) expression. Casein kinase II (CK2), a protein kinase, is known to activate hLa by phosphorylating Ser(366). Tetrabromobenzimidazole (TBBz) has been shown to be a specific inhibitor of CK2 activity, which suggests that TBBz may be useful for reducing HBV gene expression. The aim of our study was to determine whether inhibition of CK2 by TBBz and decreased phosphorylation of hLa Ser(366) (pLa) would reduce HBV gene expression. pLa and total La expression levels were evaluated by immunohistochemistry in human liver tissues with or without HBV infection. HepG2.2.15 cells (an HBV-expressing cell line) were treated with TBBz, and cell viability and pLa levels were evaluated. Knockdown of hLa and CK2 levels by specific siRNA and mutant hLa Ala(366) were utilized to establish the roles of pLa and CK2 in HBV gene expression. HBV DNA replication and HBsAg and HBeAg levels were analysed in HepG2.2.15 cell supernatants by standard methods. pLa was significantly overexpressed in HBV-infected human liver samples. TBBz decreased the phosphorylation of hLa, which coincided with decreased HBV expression. Mutant hLa Ala(366) had reduced viral expression compared with hLa Ser(366) treatment in hLa siRNA knockdown cells. Knockdown of CK2 also decreased the HBV parameters. hLa plays a key role in the regulation of HBV gene expression in a CK2-dependent mechanism via phosphorylation of hLa at Ser(366).

Variability of glucose-lowering effect as a limiting factor in optimizing basal insulin therapy: a review.

Lowering blood glucose with insulin therapy towards beneficial target levels while also avoiding hypoglycaemia is a challenging task. An important confounding factor, which might be under-appreciated in this scenario, is that of variable glucose readings causing difficulties with dose adjustment. Furthermore, this glucose variability is, to some extent, a reflection of variability in the glucose-lowering action of the insulin therapy itself. Not only is glucose variability a major confounding factor in disease management but it is possibly also of direct prognostic consequence and is increasingly recognized as an informative measurement in diabetes management. The scope for insulin-induced glucose variability is particularly great with basal insulins because of their prolonged absorption from high-dose depots. Pharmacodynamic (PD) variability manifests as both fluctuations in the level of glucose-lowering effect over time, and as inconsistencies in the response from one injection to another. Well-controlled pharmacokinetic (PK)/PD studies using repeated isoglycaemic clamp methodology clearly how that many injected basal insulin products have high variable absorption with correspondingly variable action. Incomplete resuspension and precipitation appear to be important issues with regard to unpredictability in this action, while an inadequate duration of action relative to the dosing interval results in a fluctuating action profile. There are some ultra-long-acting basal insulins with novel protraction mechanisms currently in clinical development for which clamp studies show markedly improved PK/PD profiles.

A comparison of insulin detemir and neutral protamine Hagedorn (isophane) insulin in the treatment of diabetes: a systematic review.

The aim of this review is to summarize the clinical efficacy, tolerability and safety data of insulin detemir, and compare its use with that of neutral protamine Hagedorn (NPH) insulin in randomized controlled trials in people with type 1 or type 2 diabetes. A literature search was conducted with PubMed using predefined search terms. Studies were included if they met the following criteria: randomized, controlled trial, comparison of insulin detemir with NPH insulin, non-hospitalized adults aged ≥18 years with either type 1 or type 2 diabetes, and study duration of ≥12 weeks. The following types of studies were excluded: non-randomized controlled trials, studies of mixed cohorts of patients with type 1 or type 2 diabetes that did not report results separately, pharmacokinetic/pharmacodynamic studies, reviews, pooled or meta-analyses or health-economic analyses. Fourteen publications met the inclusion criteria. Nine studies in people with type 1 diabetes and three studies in people with type 2 diabetes, using insulin detemir in a basal-bolus regimen were included. Two studies were in people with type 2 diabetes using insulin detemir with oral antidiabetes medicines. In 14 studies of people with type 1 or type 2 diabetes, insulin detemir treatment provided similar or better glycaemic control, lower within-subject variability, similar or lower frequency of hypoglycaemia and less weight gain when compared with NPH insulin.