An overview of insulin glargine

Controlled release of modified insulin glargine from novel biodegradable injectable gels

The objective of this study was to investigate the duration of biological effects of modified insulin glargine released from a novel biodegradable injectable gel in type II diabetic Zucker diabetic fatty (ZDF) rats. Modified insulin glargine was purified from the marketed formulation by process of dialysis followed by freeze-drying, and the purity was confirmed by the single peak, corresponding to insulin glargine in the HPLC chromatogram. To determine and to compare the biological activity of purified insulin glargine with marketed formulation, it was suspended in isotonic saline solutions and administered subcutaneously to ZDF rats at a dose of 10 IU/kg of insulin and the blood glucose levels were measured. The blood glucose levels of ZDF rats after a subcutaneous injection of a suspension of purified insulin glargine decreased below 200 mg/dL within 2 h and remained at this level up to 6 h, then steadily raised above 400 mg/dL in 12 h. Insulin glargine particles were loaded into a novel biodegradable injectable gel formulation prepared from a blend of polylactic-co-glycolic acid (PLGA) and biocompatible plasticizers. Approximately 0.1 mL of insulin glargine-loaded gel prepared with PLGA was administered subcutaneously to the ZDF rats, and blood glucose levels were measured. The PLGA gel formulations prepared with insulin glargine particles had duration of action of 10 days following a single subcutaneous injection. The addition of zinc sulfate to the formulations prepared with purified insulin glargine particles further slowed down the drop in blood glucose concentrations.

In vitro metabolic and mitogenic signaling of insulin glargine and its metabolites

Background

Insulin glargine (Lantus®) is a long-acting basal insulin analog that demonstrates effective day-long glycemic control and a lower incidence of hypoglycemia than NPH insulin. After subcutaneous injection insulin glargine is partly converted into the two main metabolites M1 ([Gly^A21]insulin) and M2 ([Gly^A21,des-Thr^B30]insulin). The aim of this study was to characterize the glargine metabolites in vitro with regard to their insulin receptor (IR) and IGF-1 receptor (IGF1R) binding and signaling properties as well as their metabolic and mitogenic activities.

Methods

The affinity of human insulin, insulin glargine and its metabolites to the IR isoforms A and B or IGF1R was analyzed in a competitive binding assay using SPA technology. Receptor autophosphorylation activities were studied via In-Cell Western in CHO and MEF cells overexpressing human IR-A and IR-B or IGF1R, respectively. The metabolic response of the insulins was studied as stimulation of lipid synthesis using primary rat adipocytes. Thymidine incorporation in Saos-2 cells was used to characterize the mitogenic activity.

Conclusions

The binding of insulin glargine and its metabolites M1 and M2 to the IR were similar and correlated well with their corresponding autophosphorylation and metabolic activities in vitro. No differences were found towards the two IR isoforms A or B. Insulin glargine showed a higher affinity for IGF1R than insulin, resulting in a lower EC₅₀ value for autophosphorylation of the receptor and a more potent stimulation of thymidine incorporation in Saos-2 cells. In contrast, the metabolites M1 and M2 were significantly less active in binding to and activation of the IGF1R and their mitogenicity in Saos-2 cells was equal to human insulin. These findings strongly support the idea that insulin glargine metabolites contribute with the same potency as insulin glargine to blood glucose control but lead to significantly reduced growth-promoting activity.

The cost-effectiveness of insulin glargine vs. neutral protamine Hagedorn insulin in type 2 diabetes: a focus on health economics

Diabetes mellitus is a major public health problem, in particular because of long-term complications affecting essential organs, such as the eyes and kidneys, which can lead to a reduction in life expectancy and high healthcare costs. The number of individuals with diabetes mellitus is projected to rise worldwide from 171 million people in 2000 to 366 million people in 2030. With the number of patients with diabetes continually growing, the burden of pressure on worldwide health systems is huge. Accordingly, regulatory and marketing approvals of new medicines are beginning to incorporate economic evaluation techniques to determine their cost-effectiveness. Overall, the studies included in this review show that the initiation of insulin glargine is cost-effective and is expected to lead to substantial improvements in both life years (LYs) and quality-adjusted LYs compared with neutral protamine Hagedorn insulin.

The effect of insulin glargine and nutritional model on metabolic control, quality of life and behavior in children and adolescents with type 1 diabetes mellitus

To determine the impact of glargine insulin therapy with different nutritional models on key parameters of diabetes including quality of life, behavior in children and adolescents with type 1 diabetes. Age, duration of diabetes, HbA1c, anthropometric data and episodes of severe hypoglycemia were taken from patients' charts. Diabetes quality of life scale and childhood behavior checklist questionnaires were given to each child at the start and at the end of 6 months. Mean age when starting on glargine insulin was 15.5 +/- 3. 8 years. Duration of diabetes was 7.1 +/- 4.3 years. About 14 of the patients chose to be in the carbohydrate counting group, whereas 24 of them continued with exchange meal plan as nutritional model. There was a reduction in HbA1c levels from 7.86 to 7.1% in the carbohydrate group and 8.8 to 8.0% in the exchange meal plan group. Total daily insulin dose did not change in both of the groups. BMI did not change in both of the groups. Diabetes-related worries decreased in carbohydrate group. No change was found in the behavior scores in both of the groups at the end of the study period. The use of glargine therapy among adolescents with type 1 diabetes was associated with improved overall glycemic control.

A randomized, controlled trial comparing twice-a-day insulin glargine mixed with rapid-acting insulin analogs versus standard neutral protamine Hagedorn (NPH) therapy in newly diagnosed type 1 diabetes

OBJECTIVE

Insulin glargine is difficult to use for children due to the number of injections required because it is claimed to be immiscible with rapid-acting insulin analogs. For this study, we hypothesized that treating new-onset type 1 diabetes with twice-daily insulin glargine plus a rapid-acting insulin analog mixed in the same syringe would result in better glycosylated hemoglobin than twice-daily neutral protamine Hagedorn with a rapid-acting insulin analog (standard treatment).

METHODS

Forty-two patients with new-onset type 1 diabetes were started on standard treatment. Three months after diagnosis, if patients were found compliant and had a glycosylated hemoglobin level of < or = 9%, then they were randomly assigned either to receive insulin glargine twice daily mixed with a rapid-acting insulin analog or to continue on standard treatment for 3 more months. Additional lunchtime rapid-acting insulin analog injections were given for the insulin glargine group as necessary.

RESULTS

Nineteen patients in the insulin glargine group and 17 in the neutral protamine Hagedorn group completed the study. The glycosylated hemoglobin level at baseline was 6.8% +/- 1% vs 6.9% +/- 1% and at poststudy was 6.7% +/- 1.3% vs 7.6% +/- 1% in the insulin glargine versus neutral protamine Hagedorn group, respectively. Two patients in the insulin glargine group required lunch rapid-acting insulin analog in the last month of the study. Although both groups were encouraged to contact the principal investigator with all queries, more in the insulin glargine arm opted to do so.

CONCLUSIONS

Glycemic control with insulin glargine mixed with a rapid-acting insulin analog given twice daily seems significantly more effective than the standard therapy in newly diagnosed type 1 diabetes. Furthermore, it decreases pain and burden of injections for children with diabetes by allowing patients to mix glargine with rapid-acting insulin analog.

Insulin use in elderly diabetic patients

The prevalence of type 2 diabetes is increasing among older adults as is their diabetes-related mortality rate. Studies suggest that tighter glucose control reduces complications in elderly patients. However, too low a glycosylated hemoglobin (HbA_1c) value is associated with increased hypoglycemia. Moreover, the appropriateness of most clinical trial data and standards of care related to diabetes management in elderly patients is questionable given their heterogeneity. Having guidelines to safely achieve glycemic control in elderly patients is crucial. One of the biggest challenges in achieving tighter control is predicting when peak insulin action will occur. The clinician’s options have increased with new insulin analogs that physiologically match the insulin peaks of the normal glycemic state, enabling patients to achieve the tighter diabetes control in a potentially safer way. We discuss the function of insulin in managing diabetes and how the new insulin analogs modify that state. We offer some practical considerations for individualizing treatment for elderly patients with diabetes, including how to incorporate these agents into current regimens using several methods to help match carbohydrate intake with insulin requirements. Summarizing guidelines that focus on elderly patients hopefully will help reduce crises and complications in this growing segment of the population.

Glargine blood biotransformation: in vitro appraisal with human insulin immunoassay

AIM

Glargine, a long-acting insulin analogue, is metabolized in the bloodstream and in subcutaneous tissue. Glargine metabolism and its implications for diabetes therapy remain poorly understood. The aim of our study was to assess in vitro the glargine blood biotransformation and its inter-individual variability.

METHODS

Formation of M1 glargine metabolite in vitro was studied with Elecsys Insulin immunoassay in pools of sera and sera from patients spiked with glargine. Elecsys Insulin assay is specific of human insulin, does not recognize glargine and its M2 metabolite but does recognize its M1 metabolite.

RESULTS

Glargine incubation with serum resulted in M1 metabolite formation which was detected and characterized as an enzymatic process: metabolite kinetics were dependant on temperature, substrate concentration and serum proportion. Carboxypeptidase inhibitors and chelating agents partially inhibited the activity of the enzyme(s). Glargine biotransformation was decreased when blood was collected on EDTA tubes. After 30 min incubation of glargine (100 mU/l) in 69 sera at 37 degrees C, percentage of glargine converted into M1 ranged from 46% to 98% (mean 72%; S.D. 11%).

CONCLUSION

Glargine blood biotransformation is an enzymatic process probably involving serum carboxypeptidase(s). Metabolite formation is rapid and non negligible. Inter-individual variability of glargine biotransformation is noteworthy and should be confronted to M1 metabolite bioactivity which has not been fully documented yet.

[Rational use of insulin analogues in the treatment of type 1 diabetic children and adolescents: personal experience]

In the last decade, four fast- and long-acting insulin analogues have been created. Due to the pharmacokinetic characteristics of insulin analogues, they provide an insulin profile closer to normal physiology than can be achieved with human insulins. However, they do not necessarily improve glycated haemoglobin, but they allow better quality of life. In the two daily insulin injection regime, fast-acting analogues are very useful to rapidly correct hyperglycaemia, to allow sleeping in and eating something sweet. In the basal-bolus regime (> or =4 insulin injections), long-acting analogues reduce nocturnal hypoglycaemias and improve fasting blood glucose. In the two insulin regime (2 or > or =4 injections), rapid-acting human insulin must not be systematically replaced by a fast-acting analogue. On the other hand, insulin dose alteration must be triple: retrospective, according to numerous previous experiments, in order to enjoy more freedom for meals, sports, etc.; prospective according to programmed changes in meals and sports; with only a "touch" of compensatory adaptation according to actual glycaemia.

Enhancing exposure of protein therapeutics

Therapeutic proteins have made a major impact on medicine, with significant expansion in the past two decades. The medicinal attributes of these agents, particularly their efficacy and often their safety profile, make protein therapeutics attractive, despite the general necessity of invasive (parenteral) delivery. This perceived hurdle has been a primary component in limiting expansion of this class of drug therapies. Strategies that reduce the frequency of administration directly provide greater convenience to the patient, and potentially greater efficacy, that can yield a significant treatment advantage.:

Therapy with insulin glargine (Lantus) in toddlers, children and adolescents with type 1 diabetes

OBJECTIVE

To determine the efficacy and safety of insulin glargine (IG) in children and adolescents with type 1 diabetes. In a prospective, 6-month study, 80 patients, aged 2-19 years, received IG once daily plus insulin regular or rapid analogue before meals. The data of body mass index, frequency of severe hypoglycaemia, daily mean blood glucose, fasting blood glucose, haemoglobin A1c and total daily insulin dosage before and after institution of glargine therapy were collected.

RESULTS

After 6 months, the average HbA1c level in the entire cohort dropped from 7.63+/-0.81 to 7.14+/-0.70% (p<0.001). Fasting blood glucose decreased from 161+/-37 to 150+/-35 mg/dl (p<0.05) in the total group. Severe hypoglycaemic episodes were reduced from 0.18 events per patient in the 6 months before IG therapy to 0.11 events per patient in the 6 months after IG therapy. The total daily insulin dose was reduced in the entire group from 0.90+/-0.32 to 0.83+/-0.29 u/kg/day (p<0.05). Body mass index (BMI) remained unchanged. In the 14 preschooler children, the HbA1c dropped from 7.54+/-0.60 to 6.96+/-0.57% (p<0.05).

CONCLUSIONS

Insulin glargine is an efficacious treatment to improve metabolic control in children and adolescents with type 1 diabetes. It also improved the metabolic control in preschool-age children, without increasing the number of hypoglycaemic events.

An observational study comparing continuous subcutaneous insulin infusion (CSII) and insulin glargine in children with type 1 diabetes

OBJECTIVE

The advantages of continuous subcutaneous insulin infusion (CSII) or insulin glargine have been demonstrated both in adult and paediatric diabetic patients; however, as no data comparing these two approaches during childhood are available, we have examined the efficacy of these two intensive approaches.

RESEARCH DESIGN AND METHODS

We retrospectively evaluated data from 36 diabetic children, who had changed their previous insulin regimen [with isophane insulin (NPH) at bedtime] because of HbA1c levels >8.0%. Twenty patients underwent CSII, while the other 16 (significantly younger for age) started insulin glargine at bedtime.

RESULTS

At 6 and 12 months, CSII-treated patients showed a significant reduction in HbA1c values from 8.5 +/- 1.8 to 7.4 +/- 1.1% and to 7.6 +/- 1.2%, respectively. The insulin requirement significantly decreased from 0.93 +/- 0.2 IU/kg to 0.73 +/- 0.2 IU/kg of body weight and to 0.74 +/- 0.15 IU/kg of body weight, respectively, while no significant differences were observed for BMI SDS, fructosamine and severe hypoglycaemic events. The patients treated with glargine showed a small decline in HbA1c values from 8.9 +/- 1.7 to 8.3 +/- 0.9% (not significant) in the first 6 months of treatment and to 8.2 +/- 0.9% after 12 months.

CONCLUSION

The basal insulin supplementation can be supplied effectively in children with type 1 diabetes by either CSII or insulin glargine. As previously reported for adults, it is confirmed that CSII is the best current intensive approach aimed to the improvement of glycaemic control.