Pharmacotherapeutic group: Drugs used in diabetes, insulins and analogues for injection, long-acting.
ATC Code: A10AE04.
Pharmacology: Pharmacodynamics: Mechanism of action: Insulin glargine differs from human insulin in that the amino acid asparagine at position A21 is replaced by glycine and two arginines are added to the C-terminus of the B-chain. Insulin glargine is a human insulin analogue designed to have a low solubility at neutral pH. It is completely soluble at the acidic pH of the Basalin injection solution (pH 4). After injection into the subcutaneous tissue, the acidic solution is neutralised leading to formation of micro-precipitates from which small amounts of insulin glargine are continuously released, providing a smooth, peakless, predictable concentration/time profile with a prolonged duration of action.
Insulin glargine is metabolised into 2 active metabolites M1 and M2.
Insulin receptor binding: In vitro studies indicate that the affinity of insulin glargine and its metabolites M1 and M2 for the human insulin receptor is similar to the one of human insulin.
IGF-1 receptor binding: The affinity of insulin glargine for the human IGF-1 receptor is approximately 5 to 8-fold greater than that of human insulin (but approximately 70 to 80-fold lower than the one of IGF-1), whereas M1 and M2 bind the IGF-1 receptor with slightly lower affinity compared to human insulin.
The total therapeutic insulin concentration (insulin glargine and its metabolites) found in type 1 diabetic patients was markedly lower than what would be required for a halfmaximal occupation of the IGF-1 receptor and the subsequent activation of the mitogenic-proliferative pathway initiated by the IGF-1 receptor. Physiological concentrations of endogenous IGF-1 may activate the mitogenic-proliferative pathway; however, the therapeutic concentrations found in insulin therapy, including in Basalin therapy, are considerably lower than the pharmacological concentrations required to activate the IGF-1 pathway.
The primary activity of insulin, including insulin glargine, is regulation of glucose metabolism. Insulin and its analogues lower blood glucose levels by stimulating peripheral glucose uptake, especially by skeletal muscle and fat, and by inhibiting hepatic glucose production. Insulin inhibits lipolysis in the adipocyte, inhibits proteolysis and enhances protein synthesis.
Study GL-GLA-CT1002, a glucose clamp trial was conducted to evaluate biosimilarity with regard to pharmacokinetic (PK) and pharmacodynamic (PD) endpoints of Gan & Lee Insulin Glargine Injection (Insulin Glargine 100 U/mL) with US and EU Lantus comparator products in patients with type 1 diabetes mellitus (T1DM). This comparative study showed that Basalin is bioequivalent to Lantus.
Comparative Pharmacodynamics of Gan & Lee Insulin Glargine Injection (Insulin Glargine 100 U/mL) with US and EU Lantus comparator products: The following table displays the main (primary) analysis for treatment comparisons of the primary PD endpoints. (See Table 1.)
Click on icon to see table/diagram/image
The primary PD endpoints AUC
GIR.0-24h and GIR
max were analyzed using untransformed data for the main (primary) analysis. The results of the statistical analysis demonstrate that for AUC
GIR.0-24h and GIR
max the similarity limits (90% CI of the LS-mean treatment ratio of untransformed data within the limits of 80.00-120.00%) were met for GL glargine vs. US Lantus and the similarity limits (95% CI of the LS-mean treatment ratio of untransformed data within the limits of 80.00-120.00%) were met for GL glargine vs. EU Lantus. PD similarity of GL glargine and US Lantus and of GL glargine and EU Lantus was demonstrated.
For treatment comparison of GL glargine and US Lantus with primary PD endpoints: In the sensitivity analysis, the 90% CI of GIR
max was within the 80.00 to 125.00% limits, while the lower limit of the 90% CI of AUC
GIR.0-24h was below 80.00% (90% CI of AUC
GIR.0-24h: 78.96-98.92%).
For treatment comparison of GL glargine and EU Lantus with primary PD endpoints: The sensitivity analysis confirmed the results of the main analysis and the 95% CI of both AUC
GIR.0-24h and GIR
max were within the 80.00 to 125.00% limits.
Results of most secondary PD AUC endpoints fell within the 80.00 to 120.00% limits and further supported PD similarity of Gan & Lee Insulin Glargine to US Lantus and to EU Lantus.
The following data for clinical efficacy in the patients administered with Insulin glargine is summarized from the publicly available information of Lantus: In clinical pharmacology studies, intravenous insulin glargine and human insulin have been shown to be equipotent when given at the same doses. As with all insulins, the time course of action of insulin glargine may be affected by physical activity and other variables.
In euglycaemic clamp studies in healthy subjects or in patients with type 1 diabetes, the onset of action of subcutaneous insulin glargine was slower than with human NPH insulin, its effect profile was smooth and peakless, and the duration of its effect was prolonged.
The following graph shows the results from a study in patients: See figure.
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The longer duration of action of subcutaneous insulin glargine is directly related to its slower rate of absorption and supports once daily administration. The time course of action of insulin and insulin analogues such as insulin glargine may vary considerably in different individuals or within the same individual.
In a clinical study, symptoms of hypoglycaemia or counter-regulatory hormone responses were similar after intravenous insulin glargine and human insulin both in healthy volunteers and patients with type 1 diabetes.
In an another 5 year NPH-controlled study (NPH given bid) in 1024 type 2 diabetic patients in which progression of retinopathy by 3 or more steps on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale was investigated by fundus photography. No significant difference was seen in the progression of diabetic retinopathy when insulin glargine was compared to NPH insulin.
Paediatric population: In a randomised, controlled clinical study, paediatric patients (age range 6 to 15 years) with type 1 diabetes (n=349) were treated for 28 weeks with a basal-bolus insulin regimen where regular human insulin was used before each meal. Insulin glargine was administered once daily at bedtime and NPH human insulin was administered once or twice daily. Similar effects on glycohemoglobin and the incidence of symptomatic hypoglycemia were observed in both treatment groups, however fasting plasma glucose decreased more from baseline in the insulin glargine group than in the NPH group. There was less severe hypoglycaemia in the insulin glargine group as well. One hundred forty three of the patients treated with insulin glargine in this study continued treatment with insulin glargine in an uncontrolled extension study with mean duration of follow-up of 2 years. No new safety signals were seen during this extended treatment with insulin glargine.
A crossover study comparing insulin glargine plus lispro insulin to NPH plus regular human insulin (each treatment administered for 16 weeks in random order) in 26 adolescent type 1 diabetic patients aged 12 to 18 years was also performed. As in the paediatric study previously described , fasting plasma glucose reduction from baseline was greater in the insulin glargine group than in the NPH group. HbA1c changes from baseline were similar between treatment groups; however blood glucose values recorded overnight were significantly higher in the insulin glargine/lispro group than the NPH/regular group, with a mean nadir of 5.4 mM versus 4.1 mM. Correspondingly, the incidences of nocturnal hypoglycaemia were 32% in the insulin glargine/lispro group versus 52% in the NPH/regular group.
A 24-week parallel group study was conducted in 125 children with type 1 diabetes mellitus aged 2 to 6 years, comparing insulin glargine given once daily in the morning to NPH insulin given once or twice daily as basal insulin. Both groups received bolus insulin before meals. The primary aim of demonstrating non-inferiority of insulin glargine to NPH in all hypoglycaemia was not met and there was a trend to an increase of hypoglycemic events with insulin glargine [insulin glargine: NPH rate ratio (95% CI) =1.18 (0.97-1.44)]. Glycohaemoglobin and glucose variabilities were comparable in both treatment groups. No new safety signals were observed in this study.
Pharmacokinetics: Comparative Pharmacokinetic of Gan & Lee Insulin Glargine Injection (Insulin Glargine 100 U/mL) with US and EU Lantus comparator products: The following table displays the main (primary) analysis for treatment comparisons of the primary PK endpoints. (See Table 2.)
Click on icon to see table/diagram/image
The primary PK endpoints AUC
ins.0-24h and C
ins.max of insulin glargine M1 demonstrate that the similarity limits (90% CI of the geometric LS-mean treatment ratio within the limits of 80.00-125.00%) were met for GL glargine vs. US Lantus and for GL glargine vs. EU Lantus. PK similarity of GL glargine and US Lantus and of GL glargine and EU Lantus was demonstrated.
In the sensitivity analysis, profiles with maximum insulin glargine M1 concentrations >3 times the average C
ins.max concentration of all profiles were excluded. The results were in line with the results of the main (primary) analysis and the similarity limits were met.
Results of the secondary PK AUC endpoints (AUC
ins.0-12h, AUC
ins.12-24h, and AUC
ins.0-∞) fell within the 80.00 to 125.00% limits and further supported PK similarity.
The following data for the pharmacokinetics in various subjects administered with Insulin glargine is summarized from publicly available information of Lantus: In healthy subjects and diabetic patients, insulin serum concentrations indicated a slower and much more prolonged absorption and showed a lack of a peak after subcutaneous injection of insulin glargine in comparison to human NPH insulin. Concentrations were thus consistent with the time profile of the pharmacodynamic activity of insulin glargine. The previously presented graph shows the activity profiles over time of insulin glargine and NPH insulin.
Insulin glargine injected once daily will reach steady state levels in 2-4 days after the first dose.
When given intravenously the elimination half-life of insulin glargine and human insulin were comparable.
After subcutaneous injection of Basalin in diabetic patients, insulin glargine is rapidly metabolized at the carboxyl terminus of the Beta chain with formation of two active metabolites M1 (21A-Gly-insulin) and M2 (21A-Gly-des-30B-Thr-insulin). In plasma, the principal circulating compound is the metabolite M1. The exposure to M1 increases with the administered dose of Basalin. The pharmacokinetic and pharmacodynamic findings indicate that the effect of the subcutaneous injection with Basalin is principally based on exposure to M1. Insulin glargine and the metabolite M2 were not detectable in the vast majority of subjects and, when they were detectable their concentration was independent of the administered dose of Basalin.
In clinical studies, subgroup analyses based on age and gender did not indicate any difference in safety and efficacy in insulin glargine-treated patients compared to the entire study population.
Paediatric population: Pharmacokinetics in children aged 2 to less than 6 years with type 1 diabetes mellitus was assessed in one clinical study. Plasma "trough" levels of insulin glargine and its main M1 and M2 metabolites were measured in children treated with insulin glargine, revealing plasma concentration patterns similar to adults, and providing no evidence for accumulation of insulin glargine or its metabolites with chronic dosing.
Toxicology: Preclinical safety data: Non-clinical data reveal no special hazard for humans based on conventional studies of safety pharmacology, repeated dose toxicity, genotoxicity, carcinogenic potential, toxicity to reproduction.