Time-action profile of the soluble, fatty acid acylated, long-acting insulin analogue NN304

Derivatization with fatty acids in peptide and protein drug discovery

Peptides and proteins are widely used to treat a range of medical conditions; however, they often have to be injected and their effects are short-lived. These shortcomings of the native structure can be addressed by molecular engineering, but this is a complex undertaking. A molecular engineering technology initially applied to insulin - and which has now been successfully applied to several biopharmaceuticals - entails the derivatization of peptides and proteins with fatty acids. Various protraction mechanisms are enabled by the specific characteristics and positions of the attached fatty acid. Furthermore, the technology can ensure a long half-life following oral administration of peptide drugs, can alter the distribution of peptides and may hold potential for tissue targeting. Due to the inherent safety and well-defined chemical nature of the fatty acids, this technology provides a versatile approach to peptide and protein drug discovery.

Novel nitric oxide donor, nitrated phenylbutyrate, induces cell death of human pancreatic cancer cells and suppresses tumor growth of cancer xenografts

Pancreatic cancer has a low response rate to chemotherapy due to the low drug transferability caused by the low blood flow around the tumor. In the present study, focusing on nitric oxide (NO) for its vasodilatory and antitumor effects, a novel NO donor, a nitrated form of phenylbutyrate (NPB) was synthesized and the antitumor effect on human pancreatic cancer cells (AsPC1 and BxPC3) and xenografts was examined. Using Annexin V, NPB was confirmed to induce cell death against AsPC1 and BxPC3 in a time‑ and concentration‑dependent manner. In NPB‑exposed cells, DAF‑FM DA (a probe to detect intracellular NO) derived fluorescence was observed. Release of nitrite and nitrate from NPB in aqueous solution was very gradual until even 72 h after dissolution. Phenylbutyrate (PB) and hydroxy PB in which the nitro group of NPB was replaced with a hydroxyl group did not have the cell death‑inducing effect as observed in NPB. These results suggest that the effect of NPB was dependent on NO release form NPB. Apoptosis inhibitor, Z‑VAD FMK, had no effect on the cell death‑inducing effect of NPB, and NPB did not show significant activation of caspase‑3/7. In addition, NPB significantly decreased cellular ATP levels, suggesting that necrosis is involved in the effect of NPB. NPB also accumulated cells specifically at the S phase of the cell cycle. A single dose of NPB (10 mg/kg) into mice with established BxPC3 xenografts significantly suppressed tumor growth for at least 7 weeks without apparent toxicity. The findings of the present study indicate that NPB has potential as a novel therapeutic agent for NO‑based therapy of pancreatic cancer.

How to Achieve Sufficient Endogenous Insulin Suppression in Euglycemic Clamps Assessing the Pharmacokinetics and Pharmacodynamics of Long-Acting Insulin Preparations Employing Healthy Volunteers

The therapeutic effect of basal insulin analogs will be sustained at a rather low insulin level. When employing healthy volunteers to assess the pharmacokinetics (PK) and pharmacodynamics (PD) of long-acting insulin preparations by euglycemic clamp techniques, endogenous insulin cannot be ignored and sufficient endogenous insulin inhibition is crucial for the PD and/or PK assessment. This study aimed to explore a way to sufficiently inhibit endogenous insulin secretion. Healthy Chinese male and female volunteers were enrolled. After a subcutaneous injection of insulin glargine (IGlar) (LY2963016 or Lantus) (0.5 IU/kg), they underwent a manual euglycemic clamp for up to 24 h where the target blood glucose (BG) was set as 0.28 mmol/L below the individual’s baseline. Blood samples were collected for analysis of PK/PD and C-peptide. The subjects fell into two groups according to the reduction extent of postdose C-peptide from baseline. After matching for the dosage proportion of Lantus, there were 52 subjects in group A (C-peptide reduction<50%) and 26 in group B (C-peptide reduction≥50%), respectively. No significant difference was detected in age, body mass index, the proportion of Latus treatment and female participants. A lower basal BG was observed in group B compared to group A (4.35 ± 0.26 vs. 4.59 ± 0.22 mmol/L, p < 0.05). The clamp studies were all conducted with high quality (where BG was consistently maintained around the target and exhibited a low variety). The binary logistic regression analysis indicated low basal BG as an independent factor for the success of sufficient endogenous insulin suppression. In conclusion, setting a lower sub-baseline target BG (e.g., 10% instead of 5% below baseline) might be an approach to help achieve sufficient endogenous insulin suppression in euglycemic clamps with higher basal BG levels (e.g., beyond 4.60 mmol/L).

The ongoing evolution of basal insulin therapy over 100 years and its promise for the future

The evolution of basal insulin therapy over the past 100 years since the discovery of insulin is a testimony to the biomedical bench-to-bedside process, wherein incremental advances in the basic sciences are progressively translated over time into a series of enhancements in clinical care, each building upon the success of its predecessors. The emergence of recombinant DNA technology and the resultant biosynthesis of human insulin in the 1980s provided the critical capacity to bioengineer designer insulin analogues with pharmacokinetic and pharmacodynamic properties that can better mimic, although not fully replicate, the effects of endogenous insulin secretion. Through these efforts, basal insulin therapy has progressed over this time from first-generation analogues (glargine U-100, detemir) to second-generation analogues (glargine U-300, degludec) to ultra-long-acting formulations that are suitable for administration once weekly (icodec). Each iteration in this progression has represented a step closer towards the goal of replicating the continuous secretion of insulin that normally comprises the basal output of the pancreatic beta-cells between meals, during episodes of fasting and overnight. However, it may be that we may have reached the achievable limit in the context of an "open-loop" approach, such that only with the addition of closed loop control will we be able to achieve physiologic basal insulin replacement. In this review, we will examine the evolution of basal insulin therapy over the past 100 years and its implications for patient care and outcomes in current practice and the future.

Reduction in C-Peptide Levels and Influence on Pharmacokinetics and Pharmacodynamics of Insulin Preparations: How to Conduct a High-Quality Euglycemic Clamp Study

Objective: The aim of the study was to investigate the different extent of inhibition of endogenous insulin secretion by the reduction of C-peptide levels in an euglycemic clamp study and its effects on the evaluation of pharmacokinetics, pharmacodynamics of insulin preparations, and quality of clamp study to determine the best reduction range of C-peptide levels. Methods: Healthy Chinese male volunteers were enrolled and underwent a single-dose euglycemic clamp test. Participants were subcutaneously injected with long-acting insulin glargine (0.4 IU/kg). Blood samples were collected pretest and up to 24 h post-test to assess pharmacokinetics (PK), pharmacodynamics (PD), and C-peptide levels. Results: We divided the 39 volunteers enrolled in the study into three groups according to the reduction of C-peptide levels: group A (ratio of C-peptide reduction <30%, n = 13), group B (ratio of C-peptide reduction between ≥ 30% and <50%, n = 15), and group C (ratio of C-peptide reduction ≥50%, n = 11); there were significant differences in the three groups (p = 0.000). The upper and lower limits of blood glucose oscillation in group C was statistically lower than the other groups, the range of oscillating glucose levels in group C was -17.0 ± 6.6% to -1.1 ± 6.7%. The AUC_0-24 h in groups A, B, and C were 9.7 ± 2.2, 11.0 ± 2.9, and 11.9 ± 2.1 ng/ml × min, respectively, which indicated an increasing trend in the three groups (P _trend = 0.041). For quality assessment, the average glucose (p = 0.000) and MEFTG (p = 0.001) levels in three groups were significantly different. Conclusion: The different extent of inhibition of endogenous insulin will influence the PK/PD of insulin preparations and the quality of the euglycemic clamp. Furthermore, the ratio of C-peptide reduction should be above 50% to free from the interference of endogenous insulin, and the range of blood glucose levels should be consistently maintained at -10% to 0 in the euglycemic clamp.

Revealing the importance of carrier-cargo association in delivery of insulin and lipidated insulin

Delivery of therapeutic peptides upon oral administration is highly desired and investigations report that the cell-penetrating peptide (CPP) penetratin and its analogues shuffle and penetramax show potential as carriers to enhance insulin delivery. Exploring this, the specific aim of the present study was to understand the impact that their complexation with a lipidated or non-lipidated therapeutic cargo would have on the delivery, to evaluate the effect of differences in membrane interactions in vitro and in vivo, as well as to deduce the mode of action leading to enhanced delivery. Fundamental biophysical aspects were studied by a range of orthogonal methods. Transepithelial permeation of therapeutic peptide was evaluated using the Caco-2 cell culture model supplemented with epithelial integrity measurements, real-time assessment of the carrier peptide effects on cell viability and on mode of action. Pharmacokinetic and pharmacodynamic (PK/PD) parameters were evaluated following intestinal administration to rats and tissue effects were investigated by histology. The biophysical studies revealed complexation of insulin with shuffle and penetramax, but not with penetratin. This corresponded to enhanced transepithelial permeation of insulin, but not of lipidated insulin, when in physical mixture with shuffle or penetramax. The addition of shuffle and penetramax was associated with a lowering of Caco-2 cell monolayer integrity and viability, where the lowering of cell viability was immediate, but reversible. Insulin delivery in rats was enhanced by shuffle and penetramax and accompanied by a 10-20-fold decrease in blood glucose with immediate effect on the intestinal mucosa. In conclusion, shuffle and penetramax, but not penetratin, demonstrated to be potential candidates as carriers for transmucosal delivery of insulin upon oral administration, and their effect depended on association with both cargo and cell membrane. Interestingly, the present study provides novel mechanistic insight that peptide carrier-induced cargo permeation points towards enhancement via the paracellular route in the tight epithelium. This is different from the anticipated belief being that it is the cell-penetrating capability that facilitate transepithelial cargo permeation via a transcellular route.

Insulin and insulin analogs as antidiabetic therapy: A perspective from clinical trials

The discovery of insulin in 1921 and the progress achieved in the ensuing century highlight the promise and challenge of biochemically modifying the molecule to achieve optimization of its delivery and therapeutic efficacy. Normal endogenous insulin secretion consists of a highly orchestrated physiologic loop wherein multiple metabolic signals trigger the pancreatic β cells to secrete the precise amount of insulin into the portal system required to maintain euglycemia. Accordingly, in the treatment of diabetes, attempting to replicate this complex physiology with exogenous insulin therapy given subcutaneously presents a clinical challenge. In this context, recombinant DNA-based technology has enabled the development of insulin analogs that have been specifically designed to confer advantageous pharmacodynamic features that can better mimic endogenous insulin secretion. In this review, we discuss the development of the most widely available insulin preparations and provide evidence-based insight into their use in clinical practice.

A subcutaneous insulin pharmacokinetic model for insulin Detemir

BACKGROUND AND OBJECTIVE

Type 2 diabetes (T2D) is rapidly increasing in incidence and has significant social and economic costs. Given the increasing cost of complications, even relatively short delays in the onset of T2D can significantly reduce long-term complications and costs. Equally, recent studies have shown the onset of T2D can be delayed by use of long-acting insulin, despite the risk and concomitant low adherence. Thus, there is a strong potential motivation to develop models of long-acting insulin analogues to enable safe, effective use in model-based dosing systems. In particular, there are no current models of long-acting insulin Detemir and its unique action for model-based control. The objective of this work is to develop a first model of insulin Detemir and its unique action, and validate it against existing data in the literature.

METHODS

This study develops a detailed compartment model for insulin Detemir. Model specific parameters are identified using data from a range of published clinical studies on the pharmacokinetic of insulin Detemir. Model validity and robustness are assessed by identifying the model for each study and using average identified parameters over several dose sizes and study cohorts. Comparisons to peak concentration, time of peak concentration and overall error versus measured plasma concentrations are used to assess model accuracy and validity.

RESULTS

Almost all studies and cohorts fit literature data to within one standard deviation of error, even when using averaged identified model parameters. However, there appears to be a noticeable dose dependent dynamic not included in this first model, nor reported in the literature studies.

CONCLUSIONS

A first model of insulin Detemir including its unique albumin binding kinetics is derived and provisionally validated against clinical pharmacokinetic data. The pharmacokinetic curves are suitable for model-based control and general enough for use. While there are limitations in the studies used for validation that prevent a more complete understanding, the results provide an effective first model and justify the design and implementation of further, more precise human trials.

Molecular and Materials Engineering for Delivery of Peptide Drugs to Treat Type 2 Diabetes

Type 2 diabetes is exploding globally. Despite numerous treatment options, nearly half of type 2 diabetics are unsuccessful at properly managing the disease, primarily due to a lack of patient compliance, driven by adverse side effects as well as complicated and frequent dosing schedules. Improving the delivery of type 2 diabetes drugs has the potential to increase patient compliance and thus, greatly enhance health outcomes and quality of life. This review focuses on molecular and materials engineering strategies that have been implemented to improve the delivery of peptide drugs to treat type 2 diabetes. Peptide drugs benefit from high potency and specificity but suffer from instability and short half-lives that limit their utility as therapeutics and pose a significant delivery challenge. Several approaches have been developed to improve the availability and efficacy of antidiabetic peptides and proteins in vivo. These methods are reviewed herein and include devices, which sustain the release of peptides in long term, and molecular engineering strategies, which prolong circulation time and slow the release of therapeutic peptides. By optimizing the delivery of these peptides and proteins using these approaches, long-term glucose control can be achieved in type 2 diabetes patients.

Clinical perspectives from the BEGIN and EDITION programmes: Trial-level meta-analyses outcomes with either degludec or glargine 300U/mL vs glargine 100U/mL in T2DM

AIMS

To explore comparative glycaemic control and hypoglycaemia incidence with insulin degludec 100U/mL (IDeg) or insulin glargine 300U/mL (Gla-300) versus glargine 100U/mL (Gla-100) in trial-level meta-analyses of phase 3a clinical trials including people with type-2 diabetes.

METHODS

Meta-analyses of HbA_1c, fasting plasma glucose (FPG), average 24h self-measured plasma glucose (SMPG), pre-breakfast SMPG and hypoglycaemia incidence and rate, using data from the BEGIN (IDeg) and EDITION (Gla-300) insulin development programmes, were performed.

RESULTS

In BEGIN, despite greater FPG reduction with IDeg than Gla-100, HbA_1c reduction was greater with Gla-100 (mean difference [95% CI] in HbA_1c change: 0.09 [0.01-0.18] %) whereas in EDITION, there was no difference in FPG and HbA_1c reduction between Gla-300 and Gla-100. Risk of nocturnal confirmed (<3.1mmol/L [<56mg/dL]) or severe hypoglycaemia, but not anytime (24h) events, was lower with IDeg than Gla-100 (relative risk [RR] 0.79 [0.66-0.94]) whereas Gla-300 was associated with reduced risk of nocturnal (RR 0.75 [0.61-0.92]) and anytime (24h) (RR 0.81 [0.69-0.94]) confirmed (<3.0mmol/L [<54mg/dL]) or severe hypoglycaemia versus Gla-100.

CONCLUSIONS

These trial-level meta-analyses suggest that despite greater reductions in FPG, IDeg was associated with less improvement in HbA_1c versus Gla-100, with a hypoglycaemia benefit only evident at night. In contrast, Gla-300 showed similar HbA_1c reduction to Gla-100, accompanied by lower risk of hypoglycaemia both at night and at any time of day. Gla-300 and IDeg appear more similar than dissimilar, but head-to-head trials are required.

Understanding how pharmacokinetic and pharmacodynamic differences of basal analog insulins influence clinical practice

This article reviews pharmacokinetic (PK) and pharmacodynamic (PD) concepts relating to the pharmacology of basal insulin analogs. Understanding the pharmacology of currently available long-acting basal insulins and the techniques used to assess PK and PD parameters (e.g. the euglycemic clamp method) is important when considering the efficacy and safety of these agents, and can help in understanding the rationale for specific dosing strategies when tailoring therapy for a specific patient. Basal insulins such as insulin glargine 100 units (U)/mL and insulin detemir show improved PK/PD characteristics compared with the intermediate-acting NPH insulin, with a longer duration of action, a more consistent glucose-lowering effect and less prominent concentration peaks. However, more recently developed basal insulins (insulin glargine 300 U/mL, and insulin degludec 100 U/mL and 200 U/mL) have PK/PD profiles closer to the physiologic profile of endogenous basal insulin owing to a more evenly distributed, predictable and prolonged time-action profile that exceeds 24 hours and improved within-patient variability in glucose-lowering effect. The clinical implications and relevance of these PK/PD profiles is explored, including the potential effect of PK/PD parameters on glycemic control and hypoglycemia, and the timing of dosing. The improved PK/PD properties of newer longer-acting basal insulins may translate into clinical benefits for patients with type 1 and type 2 diabetes, such as more consistent insulin levels in the blood over 24 hours, lower intra-patient variability, a reduced risk of nocturnal hypoglycemia, and more flexibility in dosing time, all of which are important to consider when choosing a basal insulin regimen.

Pharmacy Update

The prevalence of diabetes mellitus has increased to more than 20 million people in the United States, and current estimates indicate that one third of all Americans born in the year 2000 will develop diabetes mellitus in their lifetime. The need for diabetes therapies offering improved glucose control by mimicking normal physiological properties of glucose metabolism and improving on logistics such as ease of use, self-management, monitoring, and delivery is clear. This article, part 2 of a 3-part series, reviews newer injectable insulin preparations and examines the first-to-market orally inhaled dry powdered insulin (IDPI). The information provided is tailored to diabetes educators and includes mechanism of action, pharmacokinetics, drug interactions, clinical trials, dosage and administration guidelines, side effects, and educational pearls for each insulin discussed. A detailed patient case designed to acquaint the reader with these newer insulin products and provide an understanding of clinical issues to consider when providing diabetes education to patients is included.

Insulin detemir versus glyburide in women with gestational diabetes mellitus

AIM

To evaluate the safety, efficacy and pregnancy outcomes of insulin detemir (IDet) versus glyburide treatment in women with gestational diabetes mellitus (GDM).

METHODS

We conducted a retrospective cohort study of women with GDM who were treated with either glyburide or IDet for GDM in a university-affiliated tertiary hospital.

RESULTS

Ninety-one patients with GDM were enrolled, 62 were administered glyburide and 29 IDet. Maternal age, pregestational body mass index (BMI) and rate of abnormal oral glucose tolerance test (OGTT) blood glucose values were not significantly different between groups. Good glycemic control rates were comparable. Hypoglycemic episodes were reported only in the glyburide group (19.4% versus 0%, p = 0.01). Maternal weight gain during pregnancy was significantly higher among women in the glyburide group (8.8 ± 5.1 kg, p < 0.001) compared to those in the IDet group (2.1 ± 19.9 kg, p = 0.71).

CONCLUSIONS

To the best of our knowledge, this is the first study on IDet treatment in patients with GDM. By our preliminary results, IDet is a viable treatment option in women with GDM. Further large prospective studies are needed to determine the efficacy and safety of IDet in GDM patients.

Review: Pharmacology of insulin

Diabetes is associated with microvascular and macrovascular complications leading to significant morbidity and mortality. Glycaemic control is important to prevent and delay the progression of these complications. An ideal insulin regimen in patients with diabetes would mirror the 24-hour insulin profile of a non-diabetic person and thereby prevent hyperglycaemia without inducing hypoglycaemia. This has, until recently, proved difficult to reproduce by regular subcutaneous insulin injections due to the inherent pharmacokinetic properties of the available insulins. Normoglycaemia was rarely achieved without hypoglycaemia compromising the quality of patients' lives. The advent of the new long- and short-acting insulin analogues are expected to both improve glycaemic control leading to a reduction in diabetes-related complications and reduce the incidence of hypoglycaemia thereby offering patients a better lifestyle.

Controlled release of biologics for the treatment of type 2 diabetes

Type 2 diabetes is a rapidly growing disease that poses a significant burden to the United States healthcare system. Despite the many available treatments for the disease, close to half of diagnosed type 2 diabetes cases are not properly managed, largely due to inadequate patient adherence to prescribed treatment regimens. Methods for improving delivery - and thereby easing administration - of type 2 drugs have the potential to greatly improve patient health. This review focuses on two peptide drugs - insulin and glucagon-like peptide 1 (GLP-1) - for treatment of type 2 diabetes. Peptide drugs offer the benefits of high potency and specificity but pose a significant delivery challenge due to their inherent instability and short half-life. The development of insulin and GLP-1 analogs highlights the broad spectrum of drug delivery strategies that have been used to solve these problems. Numerous structural modifications and formulations have been introduced to optimize absorption, residence time, stability, route of delivery and frequency of administration. Continual improvements in delivery methods for insulin and GLP-1 receptor agonists are paving the way towards better patient compliance and improved disease management, and thereby enhanced patient quality of life.

Weight-sparing effect of insulin detemir: a consequence of central nervous system-mediated reduced energy intake?

Insulin therapy is often associated with adverse weight gain. This is attributable, at least in part, to changes in energy balance and insulin's anabolic effects. Adverse weight gain increases the risk of poor macrovascular outcomes in people with diabetes and should therefore be mitigated if possible. Clinical studies have shown that insulin detemir, a basal insulin analogue, exerts a unique weight-sparing effect compared with other basal insulins. To understand this property, several hypotheses have been proposed. These explore the interplay of efferent and afferent signals between the muscles, brain, liver, renal and adipose tissues in response to insulin detemir and comparator basal insulins. The following models have been proposed: insulin detemir may reduce food intake through direct or indirect effects on the central nervous system (CNS); it may have favourable actions on hepatic glucose metabolism through a selective effect on the liver, or it may influence fluid homeostasis through renal effects. Studies have consistently shown that insulin detemir reduces energy intake, and moreover, it is clear that this shift in energy balance is not a consequence of reduced hypoglycaemia. CNS effects may be mediated by direct action, by indirect stimulation by peripheral mediators and/or via a more physiological counter-regulatory response to insulin through restoration of the hepatic-peripheral insulin gradient. Although the precise mechanism remains unclear, it is likely that the weight-sparing effect of insulin detemir can be explained by a combination of mechanisms. The evidence for each hypothesis is considered in this review.

Decrease in clinical hypoglycemia in young children with type 1 diabetes treated with free-mixed aspart and detemir insulin: an open labeled randomized trial

OBJECTIVE

To compare the effectiveness of a free-mix of aspart (A) and detemir (D) insulins (ADIM) with a commonly used premixed fixed-ratio aspart and neutral protamine Hagedorn (NPH) insulin mixture (ANIM) in young children with type 1 diabetes (T1D) treated with twice-daily injections. The trial thus compares not only D vs. NPH, but also flexible, personalized insulin preparations vs. a fixed premixed preparation.

RESEARCH DESIGN AND METHODS

This single-center, open-label, randomized trial included 82 children with T1D. Patients stayed on ANIM for 1 yr of optimization of disease management, then were randomized to either ANIM (N = 41) or ADIM (N = 41) for another year.

OUTCOMES

Frequency of severe or symptomatic episodes, glycated hemoglobin A1c (HbA1c), and blood glucose (BG) values.

RESULTS

Compared with ANIM, ADIM decreases symptomatic hypoglycemia by approximately 2 fold (p < 0.001) and severe hypoglycemia by 7-10 fold (p = 0.04). ADIM somewhat reduced BG variation. Mean HbA1c was comparable on ADIM (7.9 ± 0.8 %; 63 ± 9 mmol/mol) and ANIM (8.2 ± 0.7 %; 66 ± 8 mmol/mol).

CONCLUSIONS

Using a free-mixing preparation of aspart and detemir insulin decreases hypoglycemia in young children with type 1 diabetes.

Fixed combination of insulin and a glucagon-like peptide-1 analog for the treatment of type 2 diabetes, exemplified by insulin degludec and liraglutide

Insulin therapy in the management of Type 2 diabetes is often postponed and/or not adequately intensified to maintain glycemic control because of the risk of weight gain and hypoglycemia. A fixed combination of the long-acting insulin degludec and liraglutide has recently been accepted by the EMA for the management of Type 2 diabetes. The incentive for this combination is to exploit the advantages of each of the drugs while counterbalancing the side effects. Insulin degludec effectively reduces fasting plasma glucose, but carries the risk of hypoglycemia and body weight gain. Liraglutide, on the other hand, exerts glycemic control with a minimal risk of hypoglycemia and, at the same time, reduces appetite and body weight.

Open flow microperfusion: pharmacokinetics of human insulin and insulin detemir in the interstitial fluid of subcutaneous adipose tissue

AIMS

To compare the time profile of insulin detemir and human insulin concentrations in the interstitial fluid (ISF) of subcutaneous adipose tissue during constant i.v. infusion and to investigate the relationship between the pharmacokinetics of both insulin molecules in plasma and the ISF of subcutaneous adipose tissue.

METHODS

During a 6-h hyperinsulinaemic-euglycaemic clamp (plasma glucose level 8 mmol/l) human insulin (21 and 42 pmol/min/kg) or insulin detemir (209 and 417 pmol/min/kg) were infused i.v. in eight rats per dose level. Open flow microperfusion (OFM) was used to continuously assess interstitial insulin concentrations in subcutaneous adipose tissue.

RESULTS

At the lower infusion rate, insulin detemir appeared significantly later in the ISF than in the plasma (p < 0.05) and also appeared later in the ISF relative to human insulin (p < 0.005).

CONCLUSIONS

By using OFM we were able to monitor albumin-bound insulin detemir directly in the ISF of subcutaneous tissue and confirm its delayed transendothelial passage to a peripheral site of action.

Short-term effects of NPH insulin, insulin detemir, and insulin glargine on the GH-IGF1-IGFBP axis in patients with type 1 diabetes

OBJECTIVE

Insulin regulates the GH-IGF1 axis. Insulin analogs differ from human insulin in receptor affinity and possibly liver accessibility. Therefore, we compared the GH-IGF1 axis response with human NPH insulin, insulin detemir, and insulin glargine in patients with type 1 diabetes (T1D).

METHODS

A total of 17 patients (seven were women) with T1D (age of 42 (24-63) years (mean and range), BMI of 24.7 (19.5-28.3) kg/m(2), HbA1c of 7.2 (6.3-8.0) % (55 (45-64) mmol/mol), T1D duration of 26 (8-45) years) were studied using a randomized, three-period crossover design. Patients received s.c. injections of equal, individual doses of NPH, detemir, and glargine at 1800 h. Plasma glucose, serum total IGF1, bioactive IGF, IGF-binding protein (IGFBPs), and GH were measured hourly for 14 h post-injection.

RESULTS

When compared with the area under the curve (AUC) following NPH and glargine, detemir resulted in the lowest 6-14 h AUC (mean and range) of IGFBP1 (1518 (1280-1800)) vs 1621 (1367-1922) vs 1020 (860-1210) μg/l×h) and GH (17.1 (14.1-20.6) vs 15.4 (12.7-18.6) vs 10.2 (8.5-12.3) μg/l×h), but in the highest AUC of bioactive IGF (3.8 (3.5-4.2) vs 3.7 (3.4-4.0) vs 4.4 (4.1-4.8) μg/l×h) (all P<0.01). These differences were unrelated to plasma glucose. By contrast, profiles of total IGF1, IGFBP2, and IGFBP3 were comparable.

CONCLUSIONS

Independent of plasma glucose, a single dose of detemir caused larger suppression in serum IGFBP1 than NPH and glargine, whereas bioactive IGF was higher, thereby explaining the lower GH levels. Thus, detemir appears to be more liver specific than NPH insulin and glargine.

Basal insulin analogues in the management of diabetes mellitus: What progress have we made?

Insulin remains the most effective and consistent means of controlling blood glucose levels in diabetes. Since 1946, neutral protamine Hagedorn (NPH) has been the predominant basal insulin in clinical use. However, absorption is variable due to the need for resuspension and the time-action profile (peak activity 4-6 h after subcutaneous administration) confers an increased propensity for between-meal and nocturnal hypoglycaemia. In the 1980s, recombinant DNA technology enabled modifications to the insulin molecule resulting in the soluble long-acting insulin analogues, glargine and detemir. Both exhibit a lower risk of hypoglycaemia compared with neutral protamine Hagedorn due to improved time-action profiles and reduced day-to-day glucose variability. Glargine is indicated for administration once daily and detemir once or twice daily. Degludec is the latest prolonged-acting insulin which forms long subcutaneous multi-hexamers that delay absorption. Recent phase III trials in type 1 and type 2 diabetes show that degludec was non-inferior to comparators (predominantly glargine) with a minimal although inconsistent reduction in overall hypoglycaemia and a small absolute difference in nocturnal hypoglycaemia. Newer developmental agents include LY2605541 and glargine U300. LY2605541 comprises insulin lispro combined with polyethylene glycol, thereby increasing its hydrodynamic size and retarding absorption from the subcutaneous tissue. Glargine U300 is a new formulation of glargine resulting in a flatter and more prolonged time-action profile than its predecessor. This article reviews recent advances in basal insulin analogues, including a critical appraisal of the degludec trials.

Glucagon-like peptide-1 analogues: An overview

Abnormalities of the incretin axis have been implicated in the pathogenesis of type 2 diabetes mellitus. Glucagon-like peptide-1 (GLP-1) and gastroinhibitory intestinal peptide constitutes >90% of all the incretin function. Augmentation of GLP-1 results in improvement of beta cell health in a glucose-dependant manner (post-prandial hyperglycemia) and suppression of glucagon (fasting hyperglycemia), amongst other beneficial pleiotropic effects. Native GLP-1 has a very short plasma half-life and novel methods have been developed to augment its half life, such that its anti-hyperglycemic effects can be exploited. They can be broadly classified as exendin-based therapies (exenatide, exenatide once weekly), DPP-4-resistant analogues (lixisenatide, albiglutide), and analogues of human GLP-1 (liraglutide, taspoglutide). Currently, commercially available analogues are exenatide, exenatide once weekly, and liraglutide. This review aims to provide an overview of most GLP-1 analogues.

Insulin detemir: a review of its use in the management of diabetes mellitus

Insulin detemir (Levemir®) is a long-acting insulin analogue indicated for use as basal insulin therapy in patients with type 1 or 2 diabetes mellitus. The protracted action of insulin detemir is explained by increased self-association and reversible binding to albumin, which slows its systemic absorption from the injection site. In glucose-clamp studies, less within-patient variability in glucose-lowering effect was seen with insulin detemir than with neutral protamine Hagedorn (NPH) insulin or insulin glargine in patients with type 1 or 2 diabetes. The beneficial effect of insulin detemir on glycaemic control was shown in numerous randomized, open-label, multicentre trials, including when used as basal-bolus therapy in patients with type 1 or 2 diabetes and as basal therapy in addition to oral antidiabetic drugs in insulin-naive patients with type 2 diabetes. In terms of glycosylated haemoglobin (HbA(1c)).[primary endpoint in most trials], insulin detemir was generally at least as effective as NPH insulin, insulin glargine or insulin lispro protamine suspension in patients with type 1 or 2 diabetes, and at least as effective as biphasic insulin aspart in patients with type 2 diabetes. Less within-patient variability in blood glucose was also generally seen with insulin detemir than with NPH insulin in patients with type 1 or 2 diabetes. Significantly less weight gain was generally seen with insulin detemir than with NPH insulin in patients with type 1 diabetes or with insulin detemir than with NPH insulin, insulin glargine, insulin lispro protamine suspension or biphasic insulin aspart (in one study) in patients with type 2 diabetes (i.e. insulin detemir generally had a weight-sparing effect). The addition of insulin detemir to liraglutide plus metformin improved glycaemic control in insulin-naive patients with type 2 diabetes and inadequate glycaemic control, although a significantly greater reduction in bodyweight was seen in patients receiving liraglutide plus metformin than in those receiving add-on therapy with insulin detemir. Results of two trials in patients aged 2-16 or 6-17 years (and a subgroup analysis in children aged 2-5 years) indicate that a basal-bolus insulin regimen incorporating insulin detemir appears to be a suitable option for use in paediatric patients with type 1 diabetes. Less within-patient variation in self-measured fasting plasma glucose was seen with insulin detemir than with NPH insulin in one of the studies. Insulin detemir was noninferior to NPH insulin in pregnant women with type 1 diabetes in terms of the HbA(1c) value achieved at 36 gestational weeks. In addition, maternal and neonatal outcomes with insulin detemir were similar to those seen with NPH insulin. Subcutaneous insulin detemir was generally well tolerated in the treatment of patients with type 1 or 2 diabetes, including in paediatric patients and pregnant women with type 1 diabetes. The majority of adverse events, including serious adverse events, reported in insulin detemir recipients were not considered to be related to the study drug. Insulin detemir was generally associated with a significantly lower risk of nocturnal hypoglycaemia than NPH insulin in patients with type 1 or 2 diabetes, particularly nocturnal minor hypoglycaemia. In conclusion, insulin detemir is a useful option for use as basal insulin therapy in patients with type 1 or 2 diabetes.

Similarity of Insulin Detemir Pharmacokinetics, Safety, and Tolerability Profiles in Healthy Caucasian and Japanese American Subjects

The objective of this study was to compare the pharmacokinetics of insulin detemir in three ascending doses in healthy Japanese and Caucasian subjects. This was an open-label, single-center, parallel-group design evaluating 30 subjects (15 Japanese and 15 Caucasians). Subjects received a total of three subcutaneous injections (one injection per visit) of insulin detemir (0.19, 0.38, 0.75 U/kg [1 U = 24 nmol]) in ascending order. Following drug administration, subjects received intravenous glucose in 0.5-mg/kg/min increments every 30 minutes, followed by a constant rate of 2.0 mg/kg/min for up to 12 hours. For pharmacokinetic evaluations, serial blood sampling was performed over a period of 30 hours after dosing. Of the subjects, 36 were enrolled, and 30 completed the study. There was a linear dose-response relationship between the three ascending insulin detemir doses and serum insulin detemir AUC values for both the Japanese and Caucasian subjects. The two dose-response regression lines had equivalent slopes but slightly different intercepts (although not statistically significant). This difference may be due to variation in AUC, body weight differences, or chance. Six subjects discontinued the study, 2 as a result of adverse events (blood draw-related ecchymosis and hypoglycemia). The most frequent treatment-emergent adverse events (TEAE) were headache, dizziness, and reactions related to blood draws/infusion sites. All TEAEs were mild to moderate in severity. The results show that an increase in insulin detemir dose will result in a similar increase in insulin detemir concentration in the two ethnic groups. Therefore, therapeutic dosing of insulin detemir is expected to be similar in both ethnic groups, with no special dose adjustment or algorithm based on race. Insulin detemir at 0.19, 0.38, and 0.75 U/kg was generally well tolerated in both Japanese and Caucasian subjects.

Optimizing treatment strategies with insulin glargine in Type 2 diabetes

Advances in insulin therapy have made a positive contribution to improving disease management in both Type 1 and Type 2 diabetes. The development of insulin analogs with time-action characteristics has made it easier to mimic physiological insulin secretion. The parallel improvement in delivery devices has also made insulin therapy more convenient, flexible and acceptable. The inevitable progression of Type 2 diabetes means that the majority of those people will also require insulin therapy at some point in their disease course. Current treatment options are many; when to initiate insulin and which regimen to choose are among the major questions confronting physicians in today's rapidly evolving environment. This article summarizes the current strategies for initiating and optimizing the use of the basal insulin analog, insulin glargine, in Type 2 diabetes, leading to the intermediate stage of insulin therapy with the introduction of meal-related, rapid-acting insulin analogs in a stepwise manner prior to a full replacement basal-bolus regimen.

Patient empowerment and optimal glycemic control

OBJECTIVE

This review updates the clinician on strategies of insulin use and educational approaches to empower their patients to use insulin correctly in self-management treatment plans.

DESIGN AND METHODS

A PubMed literature search was conducted to identify peer-reviewed clinical trials published in English in the last 10 years. Search terms used were 'glycemic control', 'insulin', and 'type 2 diabetes'. An additional search to include the terms 'patient empowerment' and 'self-management' was also conducted. Some articles relevant to this review may not have been identified using these terms. Oral antidiabetes agents in conjunction with insulin are not addressed.

RESULTS

A total of 562 articles were initially identified. Papers that did not provide data pertinent to the efficacy and tolerance of insulin types for treatment of type 2 diabetes mellitus (T2DM) were excluded. Based on methodology, results, and clinical implications, 12 clinical trials were included for discussion in this review.

CONCLUSIONS

Patients with T2DM who are empowered with knowledge about their disease and treatment can take an active role in their diabetes care, and therefore, are more likely to achieve blood glucose and A1C goals, which can slow progression of their disease and the onset of complications. Although concentrating solely on medical information and physiological facts does not guarantee patient empowerment and self-management, educational strategies such as interactive teaching, problem solving and individualized education can have a positive impact. Insulin titration algorithms can empower patients to manage their therapy, and such algorithms are simple to use for patients treated with insulin analogs. As patients with T2DM become empowered by knowledge and gain more control of their disease, their physicians must then serve as their advisors rather than as their directors or prescribers.

Insulins: past, present, and future

This article highlights selected milestones in insulin discovery and its continued development as a pivotal therapy for diabetes. The last 90 years have witnessed tremendous progress in insulin therapy, from the initial crude, yet life-saving, animal insulin extracts to novel human insulin analogues. Although the complete physiologic replacement of insulin is inherently difficult to achieve with open-loop subcutaneously administered insulin, the continued development of improved injectable insulin formulations with superior pharmacokinetics and pharmacodynamics will enhance glucose control, and represents important clinical advances in the treatment of both type 1 and type 2 diabetes.

Special considerations with insulin therapy in older adults with diabetes mellitus

Aging is associated with alterations in insulin secretion and action. However, aging per se does not alter the pharmacokinetics of commercially available insulin and its analogues. Insulin therapy in older adults is complicated by psychosocial and physiological changes of aging. Several new insulin and insulin analogue preparations are now available for clinical use. Used as prandial (e.g. insulin lispro, insulin aspart or insulin glulisine) and basal insulin (e.g. insulin glargine, insulin detemir), these analogues simulate physiological insulin profiles more closely than the older conventional insulins. The availability of multiple insulin products provides new opportunities to achieve control of diabetes mellitus. The choice of initial insulin therapy can be made based on blood glucose profiles. Overall, these profiles can be divided into three general patterns that include: (i) round-the-clock hyperglycaemia; (ii) fasting hyperglycaemia with daytime euglycaemia; and (iii) daytime hyperglycaemia with normal fasting blood glucose levels. The prescription of insulin is a dynamic process, and the insulin regimen should be adjusted based on individual response. The goal of diabetes care in older adults is to enhance quality of life without subjecting individuals to complicated treatment regimens that may interfere with their independence in carrying out daily activities.

Insights in regulated bioanalysis of human insulin and insulin analogs by immunoanalytical methods

Despite the long and illustrious history of insulin and insulin analogs as important biotherapeutics, the regulated bioanalysis (in this article, regulated bioanalysis refers to the formalized process for generating bioanalytical data to support pharmacokinetic and toxicokinetic assessments intended for development of insulin and insulin analogs as biotherapeutics, as opposed to the analytical process used for measuring insulin as a biomarker) of these peptides remains a challenging endeavor for a number of reasons. Paramount is the fact that the therapeutic concentrations are often low in serum/plasma and not too dissimilar from the endogenous level, particularly in patients with insulin resistance, such as Type 2 diabetes mellitus. Accordingly, this perspective was written to provide helpful background information for the design and conduct of immunoassays to support regulated bioanalysis of insulin and insulin analogs. Specifically, it highlights the technical challenges for determination of insulin and insulin analogs by immunoanalytical methods that are intended to support evaluations of pharmacokinetics and toxicokinetics. In a broader sense, this perspective describes the general bioanalytical issues that are common to regulated bioanalysis of peptides and articulates some of the bioanalytical differences between conventional monoclonal antibodies and peptide therapeutics.

Pharmacokinetics and pharmacodynamics of basal insulins

The two basal insulin analogs, insulin glargine and insulin detemir, were developed to ameliorate the well-known limitations of NPH insulin. In contrast to rapid-acting analogs, which differ exclusively in terms of primary structure while sharing similar pharmacokinetics (PK) and pharmacodynamics (PD), the two long-acting insulin analogs are different chemical and structural entities, exhibiting distinct modes of protracting the insulin effect. So far, PK and PD studies of long-acting analogs have often shown conflicting results, pointing out different conclusions, thereby leading to animated controversies. The methods used in the evaluation of basal insulins might have been partially responsible as, although the euglycemic clamp technique has been broadly acknowledged to be the "gold standard" reference to assess the glucose-lowering effect of an insulin preparation, its execution and interpretation might have been substantially different across studies, in various methodological and analytical aspects, ultimately providing an explanation for some of these controversies. This review will present and describe the basic methods used in the evaluation of basal insulins and will critically summarize the points that might have been responsible for the different outcomes. The findings of glucose clamp studies demonstrate that the two long-acting insulin analogs are different, to some extent, in both their PK and PD profiles. These differences should be taken into consideration when the individual analogs are introduced to provide basal insulin supplementation to optimize blood glucose control in patients with type 1 and type 2 diabetes as well.

Insulin therapy

Insulin therapy is a vital hormone replacement therapy in type 1 diabetes mellitus. In type 2 diabetes, insulin is indicated if glycaemic goals are not reached by oral anti diabetics, as well as for metabolic detoriation, co-morbidities, surgery, pregnancy or contradictions against oral anti diabetics. Insulin preparations are characterized by the onset of the insulin action, the peak profile and duration of action. Available are short acting, long-acting and premixed preparations of human insulin, and insulin analogues. The gold standard of insulin therapy in type 1 diabetes is functional insulin therapy with a basal-bolus insulin regimen and control and adaption of the therapy by the patient. Various insulin regimens are available for treating patients with type 2 diabetes, including basal insulin supported oral therapy, supplementary mealtime injection of short acting insulin or insulin analogues, conventional insulin therapy or a basal bolus procedure. The various insulin preparations and regimens make it possible to adapt the therapy according to the patient's individual need.

Similarity of pharmacodynamic effects of a single injection of insulin glargine, insulin detemir and NPH insulin on glucose metabolism assessed by 24-h euglycaemic clamp studies in healthy humans

AIMS

Two long-acting insulin analogues, insulin glargine and insulin detemir, have been developed as alternatives to neutral protamine Hagedorn (NPH) insulin, which has been the preferred basal insulin preparation for decades. The aim was to directly compare the pharmacodynamic properties of the long-acting insulin analogues and NPH insulin after a single subcutaneous injection.

METHODS

The study was conducted as a double-blind, controlled, three-arm, crossover study including 10 healthy lean male volunteers. On three different occasions, each subject was challenged with 0.4 U kg(-1) of either insulin glargine, insulin detemir or NPH insulin. Plasma glucose was maintained at 0.3 mmol l(-1) below fasting level by glucose clamping for 24 h. C-peptide, insulin, free fatty acids (FFAs) and counter regulatory hormones were measured throughout the clamp period, whereas endogenous glucose release (EGR) was assessed by isotope dilution technique (3-(3)H-glucose).

RESULTS

The mean glucose infusion rate (GIR)-time profiles revealed no significant differences between the three preparations in the primary endpoints: Maximal GIR of approximately 3.4 mg kg(-1) min(-1) (P = 0.68), time to maximal GIR of approximately 10 h (TR(max)) (P = 0.35) and area under the GIR curve (GIR(AUC)) (P = 0.81). Compared with the other insulin preparations, EGR (see above)was lower for insulin detemir at the beginning of the clamp period (330-360 min) (P = 0.007) while GIR was lower (P = 0.005) and FFA concentrations were higher (P = 0.005) during the last 4 h of the clamp.

CONCLUSIONS

In this experimental design, only minor pharmacodynamic differences were demonstrated between insulin detemir, insulin glargine and NPH insulin.

Assessment of the mixing efficiency of neutral protamine Hagedorn cartridges

Reliable application of neutral protamine Hagedorn (NPH) insulin requires previous resuspension of the suspension by tipping over the cartridge 20 times. This procedure is considered annoying by patients. The goal of this investigation was to assess the efficiency of the mixing procedure when performed less frequently than recommended. Neutral protamine Hagedorn insulin cartridges from five different manufacturers (sanofi-aventis, Lilly, Berlin-Chemie, B. Braun, and Novo Nordisk) were emptied with doses of 28 IU in the morning and the evening over 5 days. While the first dose was obtained after a regular resuspension procedure (20x tipping over), the consecutive doses were obtained after 3, 6, 10, or 20 mixing procedures (12 cartridges per experimental series, two doses/day). Insulin concentrations of doses 1, 2, 6, and 10 were determined by high-pressure liquid chromatography. Between dosing, cartridges were stored at room temperature in a horizontal position. Comparable insulin concentrations were seen in the first correctly prepared doses. Pronounced and substantial deviations from the selected dose were observed with most of the cartridges, in particular when resuspending only 3 and 6 times. Mean absolute percentage deviations when tipping 3 times and maximally observed overdoses were: Insuman basal: 1.1 +/- 1.0%/4 IU, Humulin N: 2.6 +/- 3.4%/19 IU, Berlinsulin H basal: 4.4 +/- 6.0%/26 IU, Insulin B. Braun basal: 10.4 +/- 8.9%/38 IU, and Protaphane: 4.7 +/- 4.1%/19 IU (all p < 0.05 vs Insuman basal). Only one cartridge with three metal mixing bullets (sanofi-aventis) was resuspended efficiently with only a few mixing procedures. All other cartridges with fewer bullets were shown to deliver potentially harmful doses if used for treatment when the mixing procedure was less frequent than demanded in the instructions for use.

Treatment with insulin glargine (Lantus) increases the proliferative potency of the serum of patients with type-1 diabetes: a pilot study on MCF-7 breast cancer cells

CONTEXT AND OBJECTIVE

Insulin glargine (Lantus) stimulates growth of MCF-7 cells stronger than human insulin. We investigated if serum from diabetic patients treated with glargine versus human insulin may display a similar effect.

METHODS

Pairs of serum samples from 31 C-peptide negative type-1 diabetic patients were investigated. In cross-over fashion, 23 patients were treated with glargine plus rapid-acting insulin analogues, and similar doses of human NPH and rapid-acting insulin. For comparison, eight patients were treated with insulin detemir (Levemir) and human NPH. MCF-7 cells were incubated with 10% serum and proliferation was assessed after 72 hours.

RESULTS

Serum containing insulin glargine was 1.11(95% CI 1.05-1.18) fold more mitogenic than human insulin-containing serum (p < 0.005); mitogenicity of serum containing detemir was 0.99(95% CI 0.98-1.02) fold that of human insulin-containing serum.

CONCLUSION

The serum of diabetic patients was slightly stronger mitogenic when using glargine as compared to human insulin or detemir for treatment.

[Optimal timing of insulin detemir injection in patients with type 1 diabetes and poor metabolic control]

AIM

To compare different administration times of insulin detemir (IDet) in patients with type 1 diabetes and poor metabolic control.

MATERIAL AND METHODS

This 24-week open study included 39 people with type 1 diabetes mellitus (DM) randomized to one injection of IDet before lunch (mean 14.24 + or - 00.36 (+ or - SD) h) or at bedtime (23.19 + or - 0.42 h). Whenever target glycemia levels were not reached, the regimen was switched to insulin therapy with two injections (IDet-12h). Insulin aspart was used before main meals.

RESULTS

At week 24, only 12.2% of patients remained in the IDet bedtime group and 30.3% in the IDet before lunch group. The remaining 57.5% joined the IDet-12h group. There were no differences between the IDet before lunch and IDet bedtime groups. A subanalysis including the three groups demonstrated better metabolic control in the IDet before lunch group (glycosylated hemoglobin (HbA1c) 7.1 + or - 0.2 vs. 7.6 + or - 0.4 and 8.1 + or - 0.2% in IDet before-lunch, IDet bedtime and IDet-12h, respectively; p<0.05). An HbA1c value below 7% was achieved in 30.3% of the patients: 15.2% in the IDet before-lunch group, 3.3% in the IDet bedtime group and 12.2% in IDet-12h group. Quality of life did not differ among treatment groups.

CONCLUSIONS

One injection of IDet administered before lunch could improve metabolic control. However, most patients required two injections of IDet.

Optimizing insulin therapy in patients with type 1 and type 2 diabetes mellitus: optimal dosing and timing in the outpatient setting

Management of type 1 and type 2 diabetes is continually evolving, and among these evolving therapies is administration of insulin in its various forms. The insulin regimen needs to be tailored to each individual, not only to maximize compliance and glycemic control but also to minimize hypoglycemia and weight gain.

The role of basal insulin and glucagon-like peptide-1 agonists in the therapeutic management of type 2 diabetes--a comprehensive review

The treatment of type 2 diabetes mellitus (T2DM) has been revolutionized by the introduction of novel therapeutic regimens following the clinical approval of the long-acting basal insulin glargine 10 years ago, followed by insulin detemir and, more recently, agents that target the glucagon-like peptide (GLP)-1 system with dipeptidyl peptidase 4 (DPP-4)-resistant products, such as liraglutide and exenatide, and DPP-4 inhibitors, such as sitagliptin, saxagliptin, alogliptin, and vildagliptin. The position and clinical efficacy of the GLP-1 mimetics are less well understood, however, and how they should be best used in the context of the established clinical efficacy of long-acting insulin analogs is yet to be defined. The aim of this review is to provide a summary of the efficacy, safety, and weight changes associated with long-acting insulin analogs (insulin glargine and insulin detemir) and two GLP-1 mimetics (exenatide and liraglutide). MEDLINE, EMBASE, and BIOSIS databases were searched with a timeframe of January 1, 2003-January 12, 2009 using the following terms: "Insulin glargine," with the co-indexing terms "LANTUS" and "HOE901"; "Insulin detemir," with the co-indexing term "Levemir"; "Exenatide"; and "Liraglutide." This literature review demonstrates that GLP-1 and basal insulin therapies are effective treatment options for insulin-naïve patients with suboptimal glycemic control with oral hypoglycemic agents. There are potential advantages of basal insulin and GLP-1 therapies in particular populations of patients. Further comparative data are needed to fully investigate the relative positioning of these therapies within the T2DM treatment paradigm.

Differential effects of insulin detemir and neutral protamine Hagedorn (NPH) insulin on hepatic glucose production and peripheral glucose uptake during hypoglycaemia in type 1 diabetes

AIMS/HYPOTHESIS

We compared the symptoms of hypoglycaemia induced by insulin detemir (NN304) (B29Lys(epsilon-tetradecanoyl),desB30 human insulin) and equally effective doses of neutral protamine Hagedorn (NPH) insulin in relation to possible differential effects on hepatic glucose production and peripheral glucose uptake.

METHODS

After overnight intravenous infusion of soluble human insulin 18 participants with type 1 diabetes received subcutaneous injections of NPH insulin or insulin detemir (0.5 U/kg body weight) on separate occasions in random order. During the ensuing gradual development of hypoglycaemia cognitive function and levels of counter-regulatory hormones were measured and rates of endogenous glucose production and peripheral glucose uptake continuously evaluated using a primed constant infusion of [6,6-(2)H(2)]glucose. The study was terminated when plasma glucose concentration had fallen to 2.4 mmol/l or had reached a minimum at a higher concentration.

RESULTS

During the development of hypoglycaemia no difference between the two insulin preparations was observed in symptoms or hormonal responses. Significant differences were seen in rates of glucose flux. At and below plasma glucose concentrations of 3.5 mmol/l suppression of endogenous glucose production was greater with insulin detemir than with NPH insulin, whereas stimulation of peripheral glucose uptake was greater with NPH insulin than with insulin detemir.

CONCLUSIONS/INTERPRETATION

In participants with type 1 diabetes subcutaneously injected insulin detemir exhibits relative hepatoselectivity compared with NPH insulin, but symptoms of hypoglycaemia and hormonal counter-regulation are similar.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00760448.

Beyond the era of NPH insulin--long-acting insulin analogs: chemistry, comparative pharmacology, and clinical application

The new rDNA and DNA-derived "basal" insulin analogs, glargine and detemir, represent significant advancement in the treatment of diabetes compared with conventional NPH insulin. This review describes blood glucose homeostasis by insulin in people without diabetes and outlines the physiological application of exogenous insulin in patients with type 1 and type 2 diabetes. The requirements for optimal basal insulin treatment are discussed and the methods used in the evaluation of basal insulins are presented. An essential criterion in the development of an "ideal" basal insulin preparation is that the molecular modifications made to the human insulin molecule do not compromise safety. It is also necessary to obtain a clear understanding of the pharmacokinetic and pharmacodynamic characteristics of the two currently available basal insulin analogs. When comparing glargine and detemir, the different molar concentration ratios of the two insulin formulations should be considered along with the nonspecificity of assay systems used to determine insulin concentrations. However, euglycemic clamp studies in crossover study design provide a good basis for comparing the pharmacodynamic responses. When the latter is analyzed by results of intervention clinical trials, it is concluded that both glargine and detemir are superior to NPH in type 1 and type 2 diabetes. However, there is sufficient evidence to demonstrate that these two long-acting insulin analogs are different in both their pharmacokinetic and pharmacodynamic profiles. These differences should be taken into consideration when the individual analogs are introduced to provide basal insulin supplementation to optimize blood glucose control in patients with type 1 and type 2 diabetes as well. PubMed-Medline was searched for articles relating to pharmacokinetics and pharmacodynamics of glargine and detemir. Articles retrieved were reviewed and selected for inclusion if (1) the euglycemic clamp method was used with a duration >or=24 h, (2) a single subcutaneous dose of glargine/detemir was used, and (3) area under the curve for insulin concentrations or glucose infusion rates were calculated.

Improved glycemic control and lower frequency of severe hypoglycemia with insulin detemir; long-term experience in 105 children and adolescents with type 1 diabetes

OBJECTIVE

To assess the effect of the insulin analog detemir on glycemic control and severe hypoglycemia in children and adolescents with type 1 diabetes.

RESEARCH DESIGN AND METHODS

A retrospective chart analysis was performed in 105 patients with type 1 diabetes after switching to insulin detemir between 2004 and 2007. In children below 12 yr of age (n = 53), evening neutral protomin hagedorn (NPH) insulin was replaced by insulin detemir if therapeutic goals were not reached and blood glucose levels were unpredictable or hardly controllable. In adolescents above 12 yr of age (n = 52), insulin detemir was started when changing to intensified insulin therapy.

RESULTS

In children below 12 yr of age, hemoglobin A1c (HbA1c) at start was 8.3 +/- 0.8% and after 12 months of treatment with insulin detemir significantly lowered (7.6 +/- 0.6%, p < 0.001). In the age-group above 12 yr of age at the start of the study, the improvement of HbA1c after 12 months of treatment was less pronounced (8.0 +/- 1.2 vs. 7.6 +/- 1.0%) but still significant (p < 0.01). The risk for severe hypoglycemia was significantly decreased compared with patients attending the outpatient clinic between 1995 and 2003 (4.8/100 patient years vs. 7.6/100 patient years, p = 0.003). From the beginning to the end of the follow-up period, body mass index dropped significantly in children below 12 yr of age but no effect was observed in adolescents.

CONCLUSIONS

Use of insulin detemir allows a safe nocturnal glycemic control in children and adolescents with type 1 diabetes and is associated with significantly improved HbA1c levels and fewer severe hypoglycemic events. This makes insulin detemir a most valuable new tool for the treatment of children and adolescents with type 1 diabetes.