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

Hypoglycaemia frequency and physiological response after double or triple doses of once-weekly insulin icodec vs once-daily insulin glargine U100 in type 2 diabetes: a randomised crossover trial

AIMS/HYPOTHESIS

This study compared the frequency of hypoglycaemia, time to hypoglycaemia and recovery from hypoglycaemia after double or triple doses of once-weekly insulin icodec vs once-daily insulin glargine U100. Furthermore, the symptomatic and counterregulatory responses to hypoglycaemia were compared between icodec and glargine U100 treatment.

METHODS

In a randomised, single-centre (Department of Internal Medicine, Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria), open-label, two-period crossover trial, individuals with type 2 diabetes (age 18-72 years, BMI 18.5-37.9 kg/m2, HbA1c ≤75 mmol/mol [≤9.0%]) treated with basal insulin with or without oral glucose-lowering drugs received once-weekly icodec (for 6 weeks) and once-daily glargine U100 (for 11 days). Total weekly doses were equimolar based on individual titration of daily glargine U100 during the run-in period (target fasting plasma glucose [PG]: 4.4-7.2 mmol/l). Randomisation was carried out by assigning a randomisation number to each participant in ascending order, which encoded to one of two treatment sequences via a randomisation list prepared prior to the start of the trial. At steady state, double and triple doses of icodec and glargine U100 were administered followed by hypoglycaemia induction: first, euglycaemia was maintained at 5.5 mmol/l by variable i.v. infusion of glucose; glucose infusion was then terminated, allowing PG to decrease to no less than 2.5 mmol/l (target PGnadir). The PGnadir was maintained for 15 min. Euglycaemia was restored by constant i.v. glucose (5.5 mg kg-1 min-1). Hypoglycaemic symptoms score (HSS), counterregulatory hormones, vital signs and cognitive function were assessed at predefined PG levels towards the PGnadir.

RESULTS

Hypoglycaemia induction was initiated in 43 and 42 participants after double dose of icodec and glargine U100, respectively, and in 38 and 40 participants after triple doses, respectively. Clinically significant hypoglycaemia, defined as PGnadir <3.0 mmol/l, occurred in comparable proportions of individuals treated with icodec vs glargine U100 after double (17 [39.5%] vs 15 [35.7%]; p=0.63) and triple (20 [52.6%] vs 28 [70.0%]; p=0.14) doses. No statistically significant treatment differences were observed in the time to decline from PG values of 5.5 mmol/l to 3.0 mmol/l (2.9-4.5 h after double dose and 2.2-2.4 h after triple dose of the insulin products). The proportion of participants with PGnadir ≤2.5 mmol/l was comparable between treatments after double dose (2 [4.7%] for icodec vs 3 [7.1%] for glargine U100; p=0.63) but higher for glargine U100 after triple dose (1 [2.6%] vs 10 [25.0%]; p=0.03). Recovery from hypoglycaemia by constant i.v. glucose infusion took <30 min for all treatments. Analyses of the physiological response to hypoglycaemia only included data from participants with PGnadir <3.0 mmol/l and/or the presence of hypoglycaemic symptoms; in total 20 (46.5%) and 19 (45.2%) individuals were included after a double dose of icodec and glargine U100, respectively, and 20 (52.6%) and 29 (72.5%) individuals were included after a triple dose of icodec and glargine U100, respectively. All counterregulatory hormones (glucagon, adrenaline [epinephrine], noradrenaline [norepinephrine], cortisol and growth hormone) increased during hypoglycaemia induction with both insulin products at both doses. Following triple doses, the hormone response was greater with icodec vs glargine U100 for adrenaline at PG3.0 mmol/l (treatment ratio 2.54 [95% CI 1.69, 3.82]; p<0.001), and cortisol at PG3.0 mmol/l (treatment ratio 1.64 [95% CI 1.13, 2.38]; p=0.01) and PGnadir (treatment ratio 1.80 [95% CI 1.09, 2.97]; p=0.02). There were no statistically significant treatment differences in the HSS, vital signs and cognitive function.

CONCLUSIONS/INTERPRETATION

Double or triple doses of once-weekly icodec lead to a similar risk of hypoglycaemia compared with double or triple doses of once-daily glargine U100. During hypoglycaemia, comparable symptomatic and moderately greater endocrine responses are elicited by icodec vs glargine U100.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03945656.

FUNDING

This study was funded by Novo Nordisk A/S.

Choice of basal insulin therapy is associated with weight and height development in type 1 diabetes: A multicenter analysis from the German/Austrian DPV registry in 10 338 children and adolescents

BACKGROUND

Available basal insulin regimes differ in pharmacokinetic profiles, which may be related to subsequent changes in anthropometry in patients with type 1 diabetes. This analysis elucidates the standardized height and body mass index development (height and BMI standard deviation score [height-SDS and BMI-SDS]) in pediatric type 1 diabetes patients depending on the choice of basal insulin.

METHODS

Longitudinal data of 10 338 German/Austrian patients from the Diabetes Prospective Follow-up (DPV, Diabetes Patienten Verlaufsdokumentation) database were analyzed. Patients aged 5.0 to 16.9 years were treated exclusively with neutral protamine Hagedorn (NPH), insulin detemir (IDet), insulin glargine (IGla), or continuous subcutaneous insulin infusion (CSII) for at least 3 years. Population-based German reference data were used to calculate height-SDS and BMI-SDS. Multiple linear regression was conducted.

RESULTS

BMI-SDS increased significantly in all regimes (NPH P = .0365; IDet P = .0003; IGla P < .0001; and CSII P < .0001). Direct comparison of the therapies revealed a favorable association only for NPH vs IGla. A rise in BMI-SDS was observed for all insulins in females, but only for IGla in males. BMI-SDS increment was not observed before 8 years of age. Initially and at the end of the observation period, mean height was above the 50th percentile of the reference population. Across the cohort, height-SDS declined during the observation period, except for CSII. Apart from the 5.0- to 7.9-year-old subgroup, long-acting insulin analogues were associated with a significant loss of height-SDS.

CONCLUSIONS

Choice of basal insulin regimen might influence height development. CSII appeared to have a favorable effect on growth trajectories. All therapies were associated with an increase of BMI-SDS, most evident in females.

Characterization of viral insulins reveals white adipose tissue-specific effects in mice

Objective

Members of the insulin/insulin-like growth factor (IGF) superfamily are well conserved across the evolutionary tree. We recently showed that four viruses in the Iridoviridae family possess genes that encode proteins highly homologous to human insulin/IGF-1. Using chemically synthesized single-chain (sc), i.e., IGF-1-like, forms of the viral insulin/IGF-1-like peptides (VILPs), we previously showed that they can stimulate human receptors. Because these peptides possess potential cleavage sites to form double chain (dc), i.e., more insulin-like, VILPs, in this study, we have characterized dc forms of VILPs for Grouper iridovirus (GIV), Singapore grouper iridovirus (SGIV) and Lymphocystis disease virus-1 (LCDV-1) for the first time.

Methods

The dcVILPs were chemically synthesized. Using murine fibroblast cell lines overexpressing insulin receptor (IR-A or IR-B) or IGF1R, we first determined the binding affinity of dcVILPs to the receptors and characterized post-receptor signaling. Further, we used C57BL/6J mice to study the effect of dcVILPs on lowering blood glucose. We designed a 3-h dcVILP in vivo infusion experiment to determine the glucose uptake in different tissues.

Results

GIV and SGIV dcVILPs bind to both isoforms of human insulin receptor (IR-A and IR-B) and to the IGF1R, and for the latter, show higher affinity than human insulin. These dcVILPs stimulate IR and IGF1R phosphorylation and post-receptor signaling in vitro and in vivo. Both GIV and SGIV dcVILPs stimulate glucose uptake in mice. In vivo infusion experiments revealed that while insulin (0.015 nmol/kg/min) and GIV dcVILP (0.75 nmol/kg/min) stimulated a comparable glucose uptake in heart and skeletal muscle and brown adipose tissue, GIV dcVILP stimulated 2-fold higher glucose uptake in white adipose tissue (WAT) compared to insulin. This was associated with increased Akt phosphorylation and glucose transporter type 4 (GLUT4) gene expression compared to insulin in WAT.

Conclusions

Our results show that GIV and SGIV dcVILPs are active members of the insulin superfamily with unique characteristics. Elucidating the mechanism of tissue specificity for GIV dcVILP will help us to better understand insulin action, design new analogs that specifically target the tissues and provide new insights into their potential role in disease.

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Viral insulin/IGF1-like peptides (VILPs) are microbial members of the insulin superfamily.

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VILPs bind to human IR and IGF1R and stimulate post-receptor signaling.

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Grouper iridovirus (GIV) VILP has white adipose tissue (WAT)-specific characteristics.

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GIV VILP stimulates increased glucose uptake in WAT via increased GLUT4 expression.

Lessons for modern insulin development

There have been many advances in insulin with a realistic possibility of mimicking nature to improve insulin replacement, with a view to achieving improved metabolic control. Lessons can be learnt from the evolution of insulin, insulin development, and new advances in technology. This may lead to fewer side effects of therapy resulting in a lower risk of hypoglycaemia and less weight gain, which could in turn could reduce long-term complications for people with diabetes.

Central effects of insulin detemir on feeding, body weight, and metabolism in rats

Insulin detemir (DET) is a basal insulin analog that, in contrast to other long-acting forms of insulin, has significant weight-gain-sparing effects in diabetic patients. We hypothesized that this effect of DET may be due to its enhanced catabolic action in the central nervous system. We investigated the long-term effects of single third ventricular (3V) microinjections of equimolar doses of DET and regular insulin in normal male rats on feeding, body weight, energy expenditure (EE), and respiratory quotient (RQ). Also, in acute testing, we assessed the ability of lower doses of DET to alter feeding, EE, and RQ when microinjected directly into the paraventricular nucleus (PVN). The anabolic peptide ghrelin served as a positive control in acute testing. 3V administration of both DET (0.5-2.0 mU) and regular insulin (2.0-8.0 mU) significantly reduced feeding and body weight over 48 and 120 h, respectively, with DET yielding greater inhibitory effects. DET also stimulated greater elevations of EE and reductions of RQ over 72 and 48 h postinjection, respectively. In acute (4 h) testing, microinjections of DET (0.5 mU) into the PVN reduced feeding, increased EE, and reduced RQ, while ghrelin (100 pmol) had the opposite effects. When administered sequentially into the PVN, DET (0.25 and 0.5 mU) reversed ghrelin-induced feeding, EE, and RQ effects. These data support the notion that the weight-sparing effect of DET is at least in part based on its central catabolic action and that enhanced EE and reduced RQ may participate in this effect.

Basal insulin peglispro: Overview of a novel long-acting insulin with reduced peripheral effect resulting in a hepato-preferential action

Basal insulin peglispro (BIL) is a novel basal insulin with a flat, prolonged activity profile. BIL has been demonstrated in a dog model, in healthy men and in patients with type 1 diabetes (T1D) to have significant hepato-preferential action resulting from reduced peripheral activity. In the IMAGINE-Phase 3 clinical trial program, more than 6000 patients were included, of whom ~3900 received BIL. Of the 7 pivotal IMAGINE trials, 3 studies were double-blinded and 3 were in T1D patients. BIL consistently demonstrated a greater HbA1c reduction, less glycaemic variability and a clinically relevant reduction in the rates of nocturnal hypoglycaemia across comparator [glargine and isophane insulin (NPH)] studies. Trials using basal/bolus regimens had higher rates of total hypoglycaemia with BIL due to higher rates of daytime hypoglycaemia. Severe hypoglycaemia rates were similar to comparator among both patients with T1D or type 2 diabetes (T2D). T1D patients lost weight compared with glargine (GL). Patients with T2D tended to gain less weight with BIL than with glargine. Compared to glargine, BIL was associated with higher liver fat, triglycerides and alanine aminotransferase (ALT) levels, including a higher frequency of elevation of ALT ≥3 times the upper limit of normal, but without severe, acute drug-induced liver injury. Injection site reactions, primarily lipohypertrophy, were more frequent with BIL. In conclusion, BIL demonstrated better glycaemic control with reduced glucose variability and nocturnal hypoglycaemia but higher triglycerides, ALT and liver fat relative to conventional comparator insulin. The hepato-preferential action of BIL with reduced peripheral activity may account for these findings.

Proinsulin-Transferrin Fusion Protein Exhibits a Prolonged and Selective Effect on the Control of Hepatic Glucose Production in an Experimental Model of Type 1 Diabetes

An ideal basal insulin (INS) replacement therapy requires the distribution or action of exogenous INS to more closely mimic physiological INS in terms of its preferential hepatic action. In this paper, we introduce a novel strategy to exert liver-specific INS action by hepatic activation of INS's precursor, proinsulin (ProINS). We demonstrated the conversion of human ProINS-transferrin (Tf) fusion protein, ProINS-Tf, into an active and immuno-reactive form of INS-Tf in the liver via the slow Tf receptor mediated recycling pathway. ProINS-Tf displayed prolonged basal blood glucose lowering effects for up to 40 h in streptozotocin-induced type 1 diabetic mice following a single subcutaneous injection. The effect of ProINS-Tf on blood glucose levels was observed predominantly under fasting conditions, with little effect under free-feeding conditions. In addition, both the pyruvate tolerance assay in normal mice and the Akt-phosphorylation assay in H-4-II-E hepatoma cells indicated that the hepatic-activated ProINS-Tf possessed a much longer effect on the control of hepatic glucose production than INS. These results indicated that ProINS-Tf may serve as an effective and safe hepatoselective INS analog to reduce the frequency of INS injections as well as avert severe hypoglycemia episodes and other side effects frequently encountered with long-acting INS therapeutics due to their peripheral action.

Pursuit of a perfect insulin

Insulin remains indispensable in the treatment of diabetes, but its use is hampered by its narrow therapeutic index. Although advances in peptide chemistry and recombinant DNA-based macromolecule synthesis have enabled the synthesis of structurally optimized insulin analogues, the growing epidemics of obesity and diabetes have emphasized the need for diabetes therapies that are more efficacious, safe and convenient. Accordingly, a broad set of drug candidates, targeting hyperglycaemia plus other disease abnormalities, is now progressing through the clinic. The development of an insulin therapy that is responsive to glucose concentration remains an ultimate goal, with initial prototypes now reaching the proof-of-concept stage. Simultaneously, the first alternatives to injectable delivery have progressed to registration.

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.

Effect of subcutaneous insulin detemir on glucose flux and lipolysis during hyperglycaemia in people with type 1 diabetes

AIMS

To investigate, using a novel non-steady-state protocol, the differential effects of subcutaneous (s.c.) detemir and NPH insulin on glucose flux and lipid metabolism after insulin withdrawal.

METHODS

After a period of insulin withdrawal resulting in whole-blood glucose concentration of 7 mmol/l, 11 participants (five men, mean age 41.0 years, mean body mass index 25 kg/m(2)) with type 1 diabetes (mean glycated haemoglobin concentration 57 mmol/mol, mean diabetes duration 14 years) received 0.5 units per kg body weight s.c. insulin detemir or NPH insulin in random order. Stable isotopes of glucose and glycerol were infused intravenously throughout the study protocol.

RESULTS

Glucose concentration decreased after insulin treatment as a result of suppression of endogenous glucose production, which occurred to a similar extent with both detemir and NPH insulin. The rate of glucose disappearance (Rd) was not increased significantly with either type of insulin. When the effect of detemir and NPH insulin on glucose flux at glucose concentrations between 9 and 6 mmol/l was examined, glucose rate of appearance (Ra) was similar with the two insulins; however, glucose Rd was greater with NPH insulin than with detemir at glucose concentrations of 8.0, 8.5, 7.0 and 6.0 mmol/l (p < 0.05) The percentage change in glycerol Ra, a measure of lipolysis, was greater in the NPH group than in the detemir group (p = 0.04).

CONCLUSIONS

The results of the study are consistent with the hypothesis that detemir has a lesser effect on the periphery, as evidenced by a lesser effect on peripheral glucose uptake at specific glucose concentrations.

Weight-neutral effect of once-daily insulin detemir in Chinese type 2 diabetes patients: subgroup analysis of the SOLVE study

BACKGROUND

The present subanalysis of the Study of Once Daily Levemir (SOLVE) study was to evaluate the safety and efficacy of once-daily insulin detemir as add-on to oral antidiabetic drugs (OADs) in Chinese type 2 diabetes patients according to body mass index in a real-life setting.

METHODS

In all, 3272 eligible patients who were treated with diet, exercise, and one or more OAD were prescribed once-daily insulin detemir by their physician according to routine clinical practice and were followed-up for 24 weeks. The incidence of serious adverse reactions (SADRs), including major hypoglycemia, was the primary endpoint. Subanalyses were performed on patients in the following BMI groups: normal weight (BMI < 25 kg/m2); overweight (25 ≤ BMI < 30 kg/m2); and obese (BMI ≥ 30 kg/m2).

RESULTS

No SADRs were reported during the study. Significant improvements in glycemic levels were observed in all subgroups. For normal weight, overweight, and obese patients, the mean change in HbA1c (%/[mmol/mol]) was -1.26/-14, -1.09/-12, and -1.06/-12, respectively. The mean change in fasting plasma glucose in normal weight, overweight, and obese patients was -2.77, -2.57, and -2.71 mmol/L, respectively. Slight weight gain (0.25 kg), slight weight loss (-0.36 kg), and weight loss (-1.32 kg) were observed in the normal weight, overweight, and obese patients, respectively (P < 0.001). Linear regression analysis revealed a negative relationship between weight change and baseline BMI (slope = -0.16; P < 0.001).

CONCLUSIONS

Once-daily insulin detemir as add-on to OADs in Chinese patients with type 2 diabetes showed effective glycemic control and a low risk of hypoglycemia. Weight-neutral effects were observed in different BMI subgroups.

Changes in glucose and fat metabolism in response to the administration of a hepato-preferential insulin analog

Endogenous insulin secretion exposes the liver to three times higher insulin concentrations than the rest of the body. Because subcutaneous insulin delivery eliminates this gradient and is associated with metabolic abnormalities, functionally restoring the physiologic gradient may provide therapeutic benefits. The effects of recombinant human insulin (HI) delivered intraportally or peripherally were compared with an acylated insulin model compound (insulin-327) in dogs. During somatostatin and basal portal vein glucagon infusion, insulin was infused portally (PoHI; 1.8 pmol/kg/min; n = 7) or peripherally (PeHI; 1.8 pmol/kg/min; n = 8) and insulin-327 (Pe327; 7.2 pmol/kg/min; n = 5) was infused peripherally. Euglycemia was maintained by glucose infusion. While the effects on liver glucose metabolism were greatest in the PoHI and Pe327 groups, nonhepatic glucose uptake increased most in the PeHI group. Suppression of lipolysis was greater during PeHI than PoHI and was delayed in Pe327 infusion. Thus small increments in portal vein insulin have major consequences on the liver, with little effect on nonhepatic glucose metabolism, whereas insulin delivered peripherally cannot act on the liver without also affecting nonhepatic tissues. Pe327 functionally restored the physiologic portal-arterial gradient and thereby produced hepato-preferential effects.

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 peglispro demonstrates preferential hepatic versus peripheral action relative to insulin glargine in healthy subjects

OBJECTIVE

We evaluated the endogenous glucose production (EGP) and glucose disposal rate (GDR) over a range of doses of basal insulin peglispro (BIL) and insulin glargine in healthy subjects.

RESEARCH DESIGN AND METHODS

This was a single-center, randomized, open-label, four-period, incomplete-block, crossover study conducted in eight healthy male subjects. Subjects had 8-h euglycemic clamps performed with primed, continuous infusions of BIL (5.1 to 74.1 mU/min) in three dosing periods and insulin glargine (20 or 30 mU/m(2)/min) in a fourth period, targeted to achieve 50-100% suppression of EGP. D-[3-(3)H] glucose was infused to assess rates of glucose appearance and disappearance.

RESULTS

Mean BIL and insulin glargine concentrations (targeted to reflect the differences in intrinsic affinities of the two basal insulins) ranged from 824 to 11,400 and 212 to 290 pmol/L, respectively, and increased accordingly with increases in dose. Suppression of EGP and stimulation of GDR were observed with increasing concentrations of both insulins. At insulin concentrations where EGP was significantly suppressed, insulin glargine resulted in increased GDR. In contrast, at comparable suppression of EGP, BIL had minimal effect on GDR at lower doses and had substantially less effect on GDR than insulin glargine at higher doses.

CONCLUSIONS

The novel basal insulin analog BIL has relative hepatopreferential action and decreased peripheral action, compared with insulin glargine, in healthy subjects.

Insulin degludec is not associated with a delayed or diminished response to hypoglycaemia compared with insulin glargine in type 1 diabetes: a double-blind randomised crossover study

AIMS/HYPOTHESIS

Insulin degludec (Des(B30)LysB29(γ-Glu Nε-hexadecandioyl) human insulin; IDeg) is a new basal insulin with an ultra-long flat action profile. The acute physiological responses to hypoglycaemia with IDeg and insulin glargine (A21Gly,B31Arg,B32Arg human insulin; IGlar) were compared.

METHODS

Twenty-eight adult type 1 diabetic patients with normal hypoglycaemia awareness (age = 41 ± 12 years, HbA1c = 7.8 ± 0.6% [62.8 ± 7 mmol/mol]) were randomised to once-daily IDeg or IGlar for 5 days in a two-period crossover design. Participants and research staff were blinded to group assignment. Patients were assigned the lowest available randomisation number from a set of blinded randomisation codes provided by the trial sponsor. Hypoglycaemia was induced by administering three times the usual daily insulin dose at midnight on day 5. Plasma glucose (PG) was stabilised by glucose clamp (5.5 mmol/l) for 7-9 h post dosing. Next morning, PG was allowed to decrease stepwise from 5.5 to 3.5 mmol/l (maintained for 30 min) to 2.5 mmol/l (for 15 min). PG was then increased to 3.9 mmol/l (for 120 min), before being returned to baseline. Hypoglycaemic symptom score (HSS), hypoglycaemic awareness, cognitive function, counter-regulatory hormones and vital signs were assessed during each glucose plateau. The primary analysis was to compare IDeg vs IGlar with respect to HSS at nadir PG concentration (2.5 mmol/l).

RESULTS

The full analysis set for treatment comparisons comprised data from all 28 exposed patients. Rates of PG decline and PG at nadir were similar for IDeg and IGlar. No treatment differences in HSS (estimated difference: 0.17 [95% CI -1.71, 2.05]; p > 0.05), cognitive function or awareness were observed at any time. Growth hormone and cortisol responses during hypoglycaemia were greater with IDeg than IGlar (AUC treatment ratio [IDeg/IGlar]: 2.44 [1.30, 4.60], p < 0.01; and 1.23 [1.01, 1.50]; p < 0.05), and adrenaline (epinephrine) responses trended higher (1.40 [0.96, 2.04], p = 0.07). The rates of recovery from hypoglycaemia were similar.

CONCLUSIONS/INTERPRETATION

IDeg and IGlar elicit comparable symptomatic and cognitive responses to induced hypoglycaemia. IDeg may elicit a moderately greater endocrine response, but times to PG recovery were similar for the two insulins.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01002768.

FUNDING

Novo Nordisk.

Hepatoselectivity and the evolution of insulin

In spite of major developments in insulin production, purification, pharmaceutical formulation and methods of delivery, problems remain both in the day to day management of insulin-treated diabetes and with regard to its long-term complications. The risks of hypoglycaemia and weight gain are major concerns particularly for the patient, and the persistence of microvascular and premature macrovascular complications as the main causes of morbidity and mortality in both type 1 and type 2 diabetes is a constant reminder that our therapeutic and management strategies are inadequate. One clear and striking difference between currently available insulin treatments and normal physiology is the relative difference in exposure to insulin of the liver versus peripheral tissues. Hepatoselective insulin analogues have the potential to restore the normal hepatic to peripheral gradient in insulin action. Here, we discuss the possible therapeutic potential that such analogues may have over currently available insulin preparations. These benefits could include a lower risk of hypoglycaemia, less weight gain and a potential reduction in microvascular and macrovascular complications. We explore the evolution of insulin with hepatoselectivity in mind and possible strategies to create hepatoselective insulins.

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.

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.

Comparison of insulins detemir and glargine: effects on glucose disposal, hepatic glucose release and the central nervous system

AIMS

The effects of insulins detemir (Det) and glargine (Glar) on endogenous glucose production (EGP) and net hepatic glucose output (NHGO) were compared.

METHODS

Arteriovenous difference and tracer ([3-(3) H]glucose) techniques were employed during a two-step hyperinsulinemic euglycaemic clamp in conscious dogs (6 groups, n = 5-6/group). After equilibration and basal sampling (0-120 min), somatostatin was infused and basal glucagon was replaced intraportally. Det or Glar was infused via portal vein (Po), peripheral vein (IV), or bilateral carotid and vertebral arteries (H) at 0.1 and 0.3 mU/kg/min (low Insulin; Glar vs. Det, respectively, 120-420 min) and 4× the low insulin rate (high insulin; 420-540 min).

RESULTS

NHGO and EGP were suppressed and glucose R(d) and infusion rate were stimulated similarly by Det and Glar at both Low and high insulin with each infusion route. Non-esterified fatty acid (NEFA) concentrations during low insulin were 202 ± 37 versus 323 ± 75 µM in DetPo and GlarPo (p < 0.05) and 125 ± 39 versus 263 ± 48 µM in DetIV and GlarIV, respectively (p < 0.05). In DetH versus GlarH, pAkt/Akt (1.7 ± 0.2 vs. 1.0 ± 0.2) and pSTAT3/STAT3 (1.4 ± 0.2 vs. 1.0 ± 0.1) were significantly increased in the liver but not in the hypothalamus.

CONCLUSIONS

Det and Glar have similar net effects on acute regulation of hepatic glucose metabolism in vivo regardless of delivery route. Portal and IV detemir delivery reduces circulating NEFA to a greater extent than glargine, and head detemir infusion enhances molecular signalling in the liver. These findings indicate a need for further examination of Det's central and hepatic effects.

Insulin detemir reduces weight gain as a result of reduced food intake in patients with type 1 diabetes

OBJECTIVE

Insulin detemir lacks the usual propensity for insulin to cause weight gain. We investigated whether this effect was a result of reduced energy intake and/or increased energy expenditure.

RESEARCH DESIGN AND METHODS

A 32-week, randomized crossover design trial was undertaken in 23 patients with type 1 diabetes. Patients on a basal-bolus regimen (with insulin aspart as the bolus insulin) were randomly assigned to insulin detemir or NPH insulin as a basal insulin for 16 weeks, followed by the other basal insulin for 16 weeks. At the end of each 16-week period, total energy expenditure, resting energy expenditure, diet-induced thermogenesis, activity energy expenditure, energy intake, weight change, glycemic control, hypoglycemic episodes, and hormones that affect satiety and fuel partitioning were measured.

RESULTS

After 16 weeks, weight change was -0.69±1.85 kg with insulin detemir and +1.7±2.46 kg with NPH insulin (P<0.001). Total energy intake was significantly less with insulin detemir (2,016±501 kcal/day) than with NPH insulin (2,181±559 kcal/day) (P=0.026). There was no significant difference in any measure of energy expenditure, HbA1c percentage, or number of hypoglycemic episodes. Leptin was lower and resistin was higher with insulin detemir compared with NPH insulin (P=0.039, P=0.047). After the meal, ghrelin and pancreatic polypeptide levels (P=0.002, P=0.001) were higher with insulin detemir.

CONCLUSIONS

The reduced weight gain with insulin detemir compared with NPH insulin is attributed to reduced energy intake rather than increased energy expenditure. This may be mediated by a direct or indirect effect of insulin detemir on the hormones that control satiety.

Differences in bioactivity between human insulin and insulin analogues approved for therapeutic use- compilation of reports from the past 20 years

In order to provide comprehensive information on the differences in bioactivity between human insulin and insulin analogues, published in vitro comparisons of human insulin and the rapid acting analogues insulin lispro (Humalog®), insulin aspart ( NovoRapid®), insulin glulisine (Apidra®), and the slow acting analogues insulin glargine (Lantus®), and insulin detemir (Levemir®) were gathered from the past 20 years (except for receptor binding studies). A total of 50 reports were retrieved, with great heterogeneity among study methodology. However, various differences in bioactivity compared to human insulin were obvious (e.g. differences in effects on metabolism, mitogenesis, apoptosis, intracellular signalling, thrombocyte function, protein degradation). Whether or not these differences have clinical bearings (and among which patient populations) remains to be determined.

Critical appraisal of the safety and efficacy of insulin detemir in glycemic control and cardiovascular risk management in diabetics

Insulin detemir is an analog of human insulin designed to provide a long duration of basal insulin action. This is achieved by protracted absorption from the injection depot, which results in part from increased self-association of insulin detemir molecules and in part from reversible albumin binding. Subsequent albumin binding in the circulation is thought to buffer changes in the effects at target tissues that could otherwise arise from variability in absorption rate. In consequence, insulin detemir has shown a less variable pharmacodynamic profile than alternative basal insulins; this manifests as more consistent temporal glucose reduction profiles in repeat-clamp studies. In clinical trials, insulin detemir has been characterized by consistent risk reductions in hypoglycemia, as well as reduced weight gain in comparison with other basal insulins. Given some recent associations that have been made in prospective and epidemiologic studies between glucose variability and/or hypoglycemia and increased cardiovascular risk, and the long-known association between excess weight and cardiovascular risk, it is possible that the clinical profile of insulin detemir may carry prognostic value with regard to cardiovascular safety, although this is yet to be substantiated. There have also been some concerns raised recently over the use of insulin analogs and cancer risk, but available clinical data and the receptor interaction profile of insulin detemir suggest no excess in risk in comparison with human insulin therapy. Optimal approaches for the clinical use of insulin detemir have been emerging through an increasing clinical study base, and the analog is becoming established as a potentially valuable therapy option.

Effect of glucagon-like peptide-1 on alpha- and beta-cell function in C-peptide-negative type 1 diabetic patients

CONTEXT

The mechanism by which glucagon-like peptide-1 (GLP-1) suppresses glucagon secretion is uncertain, and it is not determined whether endogenous insulin is a necessary factor for this effect.

OBJECTIVE

To characterize the alpha- and beta-cell responses to GLP-1 in type 1 diabetic patients without residual beta-cell function.

METHODS

Nine type 1 diabetic patients, classified as C-peptide negative by a glucagon test, were clamped at plasma glucose of 20 mmol/liter for 90 min with arginine infusion at time 45 min and concomitant infusion of GLP-1 (1.2 pmol/kg x min) or saline.

RESULTS

Infusion with GLP-1 increased C-peptide concentration just above the detection limit of 33 pmol/liter in one patient, but C-peptide remained immeasurable in all other patients. In the eight remaining patients, total area under the curve of glucagon was significantly decreased with GLP-1 compared with saline: 485 +/- 72 vs. 760 +/- 97 pmol/liter x min (P < 0.001). In addition, GLP-1 decreased the arginine-stimulated glucagon release (incremental AUC of 103 +/- 21 and 137 +/- 16 pmol/liter x min, with GLP-1 and saline, respectively, P < 0.05).

CONCLUSIONS

In type 1 diabetic patients without endogenous insulin secretion, GLP-1 decreases the glucagon secretion as well as the arginine-induced glucagon response during hyperglycemia. GLP-1 induced endogenous insulin secretion in one of nine type 1 diabetic patients previously classified as being without endogenous insulin secretion.