How to Assess the Quality of Glucose Clamps? Evaluation of Clamps Performed With ClampArt, a Novel Automated Clamp Device

Pharmacokinetic and pharmacodynamic properties of once-weekly insulin icodec in individuals with type 1 diabetes

AIMS

To investigate the pharmacokinetic/pharmacodynamic properties of once-weekly insulin icodec in individuals with type 1 diabetes (T1D).

MATERIALS AND METHODS

In this randomized, open-label, two-period crossover trial, 66 individuals with T1D (age 18-64 years; glycated haemoglobin ≤75 mmol/mol [≤ 9%]) were to receive once-weekly icodec (8 weeks) and once-daily insulin glargine U100 (2 weeks) at individualized fixed equimolar total weekly doses established during up to 10 weeks' run-in with glargine U100 titrated to pre-breakfast plasma glucose (PG) of 4.4-7.2 mmol/L (80-130 mg/dL). Insulin aspart was used as bolus insulin. Blood sampling for icodec pharmacokinetics was performed from the first icodec dose until 35 days after the last dose. The glucose infusion rate at steady state was assessed in glucose clamps (target 6.7 mmol/L [120 mg/dL]) at 16-52 h and 138-168 h after the last icodec dose and 0-24 h after the last glargine U100 dose. Icodec pharmacodynamics during 1 week were predicted by pharmacokinetic-pharmacodynamic modelling. Hypoglycaemia was recorded during the treatment periods based on self-measured PG.

RESULTS

Icodec reached pharmacokinetic steady state on average within 2-3 weeks. At steady state, model-predicted daily proportions of glucose infusion rate during the 1-week dosing interval were 14.3%, 19.6%, 18.3%, 15.7%, 13.1%, 10.6% and 8.4%, respectively. Rates and duration of Level 2 hypoglycaemic episodes (PG <3.0 mmol/L [54 mg/dL]) were 32.8 versus 23.9 episodes per participant-year of exposure and 33 ± 25 versus 30 ± 18 min (mean ± SD) for icodec versus glargine U100.

CONCLUSIONS

The pharmacokinetic/pharmacodynamic properties of icodec suggest its potential to provide basal coverage in a basal-bolus insulin regimen in people with T1D.

Pharmacokinetic and pharmacodynamic properties of once-weekly insulin icodec in individuals with type 2 diabetes

AIMS

To characterize the pharmacokinetic and pharmacodynamic properties of once-weekly insulin icodec in type 2 diabetes (T2D).

MATERIALS AND METHODS

In an open-label trial, 46 individuals with T2D (18-75 years; body mass index 18.0-38.0 kg/m2 ; glycated haemoglobin ≤75 mmol/mol [≤9%]; basal insulin-treated) received subcutaneous once-weekly icodec for ≥8 weeks at individualized doses, aiming at a pre-breakfast plasma glucose concentration of 4.4 to 7.0 mmol/L (80-126 mg/dL) on the last three mornings of each weekly dosing interval. Frequent blood sampling to assess total serum icodec concentration (ie, albumin-bound and unbound) occurred from first icodec dose until 35 days after last dose. Icodec trough concentrations following initiation of once-weekly dosing were predicted by pharmacokinetic modelling. During the final 3 weeks of icodec treatment, while at steady state, the icodec glucose-lowering effect was assessed in three glucose clamps (target 7.5 mmol/L [135 mg/dL]): 0 to 36, 40 to 64 and 144 to 168 h post-dose, thus covering the initial, middle and last part of the 1-week dosing interval. Glucose-lowering effect during a complete dosing interval was predicted by pharmacokinetic-pharmacodynamic modelling.

RESULTS

Model-predicted icodec steady state was attained after 3 to 4 weeks. At steady state, model-predicted daily proportions of glucose-lowering effect on days 1 to 7 of the 1-week dosing interval were 14.1%, 16.1%, 15.8%, 15.0%, 14.0%, 13.0% and 12.0%, respectively. Icodec duration of action was at least 1 week in all participants. Once-weekly icodec was overall safe and well tolerated in the current trial.

CONCLUSIONS

The pharmacokinetic and pharmacodynamic characteristics of icodec in individuals with T2D support its potential as a once-weekly basal insulin.

Clinical evaluation of a decision support system for glucose infusion in hypoglycaemic clamp experiments

AIM

To provide a preliminary evaluation of the accuracy and safety of Gluclas decision support system suggestions in a hypoglycaemic clamp study.

METHODS

This analysis was performed using data from 32 participants (four groups with different glucose-insulin regulation: post Roux-en-Y gastric bypass with and without postprandial hypoglycaemia syndrome, postsleeve gastrectomy and non-operated controls) undergoing Gluclas-assisted hypoglycaemic clamps (target: 2.5 mmol/L for 20 minutes at 150 minutes after oral glucose ingestion). Gluclas provided glucose infusion rate suggestions upon manual entry of blood glucose values (every 5 minutes), which were either followed or overruled by investigators after critical review. Accuracy and safety were evaluated by mean absolute error (MAE), mean absolute percentage error (MAPE), average glucose level, coefficient of variation (CV) and minimal glucose level during the 20-minute hypoglycaemic period.

RESULTS

Investigators accepted 84% of suggestions, with a mean deviation of 30.33 mg/min. During the hypoglycaemic period, the MAE was 0.16 (0.12-0.24) (median [interquartile range]) mmol/L and the MAPE was 6.12% (4.80%-9.29%). CV was 4.90% (3.58%-7.27%), with 5% considered the threshold for sufficient quality. The minimal glucose level was 2.40 (2.30-2.50) mmol/L.

CONCLUSIONS

Gluclas achieved sufficiently high accuracy with minimal safety risks in a population with differences in glucose-insulin dynamics, underscoring its applicability to various patient groups.

Pharmacokinetic and pharmacodynamic bioequivalence of Gan & Lee insulin analogues aspart (rapilin®), lispro (prandilin®) and glargine (basalin®) with EU- und US-sourced reference insulins

AIM

For the successful approval and clinical prescription of insulin biosimilars, it is essential to show pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence to the respective reference products sourced from the European Union and the United States.

METHODS

Three phase 1, randomized, double-blind, three-period crossover trials compared single doses of the proposed biosimilar insulin analogues aspart (GL-Asp, n = 36), lispro (GL-Lis, n = 38) and glargine (GL-Gla, n = 113), all manufactured by Gan & Lee pharmaceuticals, to the respective EU- and US-reference products in healthy male participants (GL-Asp and GL-Lis) or people with type 1 diabetes (GL-Gla). Study participants received 0.2 U/kg (aspart and lispro) or 0.5 U/kg (glargine) of each treatment under automated euglycaemic clamp conditions. The clamp duration was 12 h (aspart and lispro) or 30 h (glargine). Primary PK endpoints were the total area under the PK curves (AUCins.total ) and maximum insulin concentrations (Cins.max ). Primary PD endpoints were the total area under the glucose infusion rate curve (AUCGIR.total ) and maximum glucose infusion rate (GIRmax ).

RESULTS

Bioequivalence to both EU- and US-reference products were shown for all three GL insulins. Least squares mean ratios for the primary PK/PD endpoints were close to 100%, and both 90% and 95% confidence intervals were within 80%-125% in all three studies. There were no noticeable differences in the safety profiles between test and reference insulins, and no serious adverse events were reported for the GL insulins.

CONCLUSION

GL-Asp, GL-Lis and GL-Gla are bioequivalent to their EU- and US-reference products.

Leveraging Clinical Pharmacology Data to Assess Biosimilarity and Interchangeability of Insulin Products

There is over a hundred years of clinical experience with insulin for the treatment of diabetes. The US Food and Drug Administration (FDA) approved the first insulin biosimilar interchangeable product in 2021 for improving glycemic control in adults and pediatric patients with type 1 diabetes mellitus and in adults with type 2 diabetes mellitus. Several recombinant insulin products are available in the United States, including the recently approved biosimilar insulins. The approval of the biosimilar insulin products was based on comparative analytical characterizations and comparative pharmacokinetic (PK) and pharmacodynamic (PD) data. The primary objective of this review is to discuss the scientific considerations in the demonstration of biosimilarity of a proposed insulin biosimilar to a reference product and the role of clinical pharmacology studies in the determination of biosimilarity and interchangeability. Euglycemic clamp studies are considered a "gold standard" for insulin PK and PD characterization and have been widely used to determine the time-action profiles of rapid-acting, intermediate-acting, and long-acting insulin products. Clinical pharmacology aspects of study design, including selection of appropriate dose, study population, PK, and PD end points, are presented. Finally, the role of clinical pharmacology studies in the interchangeability assessment of insulin and the regulatory pathways used for insulin and the experience with follow-on insulins and the two recently approved biosimilar insulin products is discussed.

Pharmacokinetic and pharmacodynamic equivalence of Biocon's biosimilar insulin N with US-licensed Humulin® N formulation in healthy subjects: Results from the RHINE-2 (Recombinant Human INsulin Equivalence-2) study

AIM

To establish the pharmacokinetic (PK) and pharmacodynamic (PD) equivalence of proposed biosimilar Insulin N (Biocon's Insulin-N; Biocon Biologics Ltd., Bangalore, India) and US-licensed Humulin® N (Humulin-N; Eli Lilly and Company, Indianapolis, IN, USA) in healthy subjects.

MATERIALS AND METHODS

This was a phase-1, single-centre, double-blind, randomized, three-period, six-sequence, partially replicated, crossover, 24-h euglycaemic clamp study. Overall, 90 healthy subjects were randomized, of whom 85 completed the study. The subjects received either two single doses of Biocon's Insulin-N and a single dose of Humulin-N or two single doses of Humulin-N and a single dose of Biocon's Insulin-N subcutaneously at a dose of 0.4 IU/kg. The primary PK endpoints were the area under the insulin concentration-time curve from 0 to 24 h (AUC_ins.0-24h ) and the maximum insulin concentration (C_ins.max ). The primary PD endpoints were the area under the glucose infusion rate (GIR) curve from 0 to 24 h (AUC_GIR.0-24h ) and the maximum GIR (GIR_max ).

RESULTS

Biocon's Insulin-N was found to be equivalent to Humulin-N for the primary PK (geometric 90% confidence interval for the least squares mean ratio: AUC_ins.0-24h , 100.98%-115.66% and C_ins.max , 95.91%-110.16%) and PD endpoints (intra-subject variability ≥0.294; 95% upper confidence interval [(μT - μR)²  - θσ² WR] <0; point estimates of geometric least squares mean ratio: AUC_GIR.0-24h , 104.61% and GIR_max , 100.81%). The safety profile of Biocon's Insulin-N was similar to that of Humulin-N, and no serious adverse events were reported.

CONCLUSION

PK and PD equivalence was shown between Biocon's Insulin-N and Humulin-N in healthy subjects, and both treatments were well tolerated and considered safe.

Pharmacokinetic and Pharmacodynamic Characteristics of Insulin Icodec After Subcutaneous Administration in the Thigh, Abdomen or Upper Arm in Individuals with Type 2 Diabetes Mellitus

BACKGROUND AND OBJECTIVE

Individuals with diabetes mellitus may prefer different body regions for subcutaneous insulin administration. This trial investigated whether choice of injection region affects exposure and glucose-lowering effect of once-weekly basal insulin icodec.

METHODS

In a randomised, open-label, crossover trial, 25 individuals with type 2 diabetes received single subcutaneous icodec injections (5.6 U/kg) in the thigh, abdomen or upper arm (9-13 weeks' washout). Pharmacokinetic blood sampling occurred frequently until 35 days post-dose. Partial glucose-lowering effect was assessed 36-60 h post-dose in a glucose clamp (target 7.5 mmol/L). Steady-state pharmacokinetics following multiple once-weekly dosing were simulated using a two-compartment pharmacokinetic model.

RESULTS

Total icodec exposure (area under the curve from zero to infinity after single dose; AUC_0-∞,SD) was similar between injection in the thigh, abdomen and upper arm (estimated AUC_0-∞,SD ratios [95% confidence interval]: abdomen/thigh 1.02 [0.96-1.09], p = 0.473; upper arm/thigh 1.04 [0.98-1.10], p = 0.162; abdomen/upper arm 0.98 [0.93-1.05], p = 0.610). Maximum icodec concentration (C_max) after single dose was higher for abdomen (by 17%, p = 0.002) and upper arm (by 24%, p < 0.001) versus thigh. When simulated to steady state, smaller differences in C_max were seen for abdomen (by 11%, p = 0.004) and upper arm (by 16%, p < 0.001) versus thigh. Geometric mean [coefficient of variation] glucose-lowering effect 36-60 h post-dose was comparable between the thigh (1961 mg/kg [51%]), abdomen (2130 mg/kg [52%]) and upper arm (2391 mg/kg [40%]).

CONCLUSION

Icodec can be administered subcutaneously in the thigh, abdomen or upper arm with no clinically relevant difference in exposure and with a similar glucose-lowering effect.

CLINICALTRIALS

GOV IDENTIFIER

NCT04582448.

Gluclas: A software for computer-aided modulation of glucose infusion in glucose clamp experiments

BACKGROUND AND OBJECTIVE

The glucose clamp (GC) is an experimental technique for assessing several aspects of glucose metabolism. In these experiments, investigators face the non-trivial challenge of accurately adjusting the rate of intravenous glucose infusion to drive subjects' blood glucose (BG) concentration towards a desired plateau level. In this work we present Gluclas, an open-source software to support researchers in the modulation of glucose infusion rate (GIR) during GC experiments.

METHODS

Gluclas uses a proportional-integrative-derivative controller to provide GIR suggestions based on BG measurements. The controller embeds an anti-wind-up scheme to account for actuator physical limits and suitable corrections of control action to accommodate for possible sampling jitter due to manual measurement and actuation. The software also provides a graphic user interface to increase its usability. A preliminary validation of the controller is performed for different clamp scenarios (hyperglycemic, euglycemic, hypoglycemic) on a simulator of glucose metabolism in healthy subjects, which also includes models of measurement error and sampling delay for increased realism. In silico trials are performed on 50 virtual subjects. We also report the results of the first in-vivo application of the software in three subjects undergoing a hypoglycemic clamp.

RESULTS

In silico, during the plateau period, the coefficient of variation (CV) is in median below 5% for every protocol, with 5% being considered the threshold for sufficient quality. In terms of median [5th percentile, 95th percentile], average BG level during the plateau period is 12.18 [11.58 - 12.53] mmol/l in the hyperglycemic clamp (target: 12.4 mmol/), 4.92 [4.51 - 5.14] mmol/l in the euglycemic clamp (target: 5.5 mmol/) and 2.38 [2.33 - 2.64] in the hypoglycemic clamp (target: 2.5 mmol/). Results in vivo are consistent with those obtained in silico during the plateau period: average BG levels are between 2.56 and 2.68 mmol/l (target: 2.5 mmol/l); CV is below 5% for all three experiments.

CONCLUSIONS

Gluclas offered satisfactory control for tested GC protocols. Although its safety and efficacy need to be further validated in vivo, this preliminary validation suggest that Gluclas offers a reliable and non-expensive solution for reducing investigator bias and improving the quality of GC experiments.

The glucagon receptor antagonist LY2409021 does not affect gastrointestinal-mediated glucose disposal or the incretin effect in individuals with and without type 2 diabetes

OBJECTIVE

Gastrointestinal-mediated glucose disposal (GIGD) during oral glucose tolerance test (OGTT) reflects the percentage of glucose disposal caused by mechanisms elicited by the oral route of glucose administration. GIGD is reduced in patients with type 2 diabetes (T2D) due to a reduced incretin effect and possibly also due to inappropriate suppression of glucagon after oral glucose. We investigated the effect of glucagon receptor antagonism on GIGD, the incretin effect and glucose excursions in patients with T2D and controls without diabetes.

DESIGN

A double-blind, randomised, placebo-controlled crossover study was conducted.

METHODS

Ten patients with T2D and 10 gender-, age- and BMI-matched controls underwent two 50 g OGTTs and 2 isoglycaemic i.v. glucose infusions, succeeding (~10 h) single-dose administration of 100 mg of the glucagon receptor antagonist LY2409021 or placebo, respectively.

RESULTS

Compared to placebo, LY2409021 reduced fasting plasma glucose in patients with T2D and controls. Plasma glucose excursions after oral glucose assessed by baseline-subtracted area under the curve were increased by LY2409021 compared to placebo in both groups, but no effect of LY2409021 on GIGD or the incretin effect was observed. LY2409021 increased fasting glucagon concentrations three-fold compared to placebo concentrations.

CONCLUSIONS

Glucagon receptor antagonism with LY2409021 had no effect on the impaired GIGD or the impaired incretin effect in patients with T2D and did also not affect these parameters in the controls. Surprisingly, we observed reduced oral glucose tolerance with LY2409021 which may be specific for this glucagon receptor antagonist.

Pharmacokinetic and pharmacodynamic equivalence of Biocon's biosimilar Insulin 70/30 with US-licensed HUMULIN® 70/30 formulation in healthy subjects: Results from the RHINE-3 (Recombinant Human INsulin Equivalence-3) study

AIM

To establish the pharmacokinetic (PK) and pharmacodynamic (PD) equivalence of proposed biosimilar insulin 70/30 (Biocon's Insulin-70/30) and HUMULIN® 70/30 (HUMULIN-70/30; Eli Lilly and Company, IN).

MATERIALS AND METHODS

In this phase 1, automated euglycaemic glucose clamp study, 78 healthy subjects were randomized (1:1) to receive a single dose of 0.4 IU/kg of Biocon's Insulin-70/30 and HUMULIN-70/30. Plasma insulin concentrations and glucose infusion rates (GIRs) were assessed over 24 hours. Primary PK endpoints were area under the insulin concentration-time curve from 0 to 24 hours - AUC_ins.0-24h - and maximum insulin concentration - C_ins.max . Primary PD endpoints were area under the GIR time curve from 0 to 24 hours - AUC_GIR.0-24h - and maximum GIR - GIR_max .

RESULTS

Equivalence was shown between Biocon's Insulin-70/30 and HUMULIN-70/30 for the primary PK/PD endpoints. The 90% confidence intervals of the treatment ratios were entirely within the acceptance range of 80.00%-125.00%. The secondary PK/PD profiles were also comparable. There were no clinically relevant differences in the safety profiles of the two treatments and no serious adverse events were reported.

CONCLUSION

PK/PD equivalence was demonstrated between Biocon's Insulin-70/30 and HUMULIN-70/30 in healthy subjects. Treatment with Biocon's Insulin-70/30 and HUMULIN-70/30 was well tolerated.

Pharmacokinetic and pharmacodynamic similarity evaluation between an insulin glargine biosimilar product and Lantus® in healthy subjects: Pharmacokinetic parameters of both parent insulin glargine and M1 were used as endpoints

Insulin glargine is a long-acting insulin analog, which plays an important role in the treatment of diabetes mellitus. Biosimilar products of insulin glargine can provide patients with additional safe, high-quality, and potentially cost-effective options for treating diabetes. This article presents a randomized, double-blind, single-dose, two-treatment, four-period, replicate crossover, euglycemic clamp study which was designed to evaluate the PK and PD similarity between the recombinant insulin glargine developed by Wanbang (test) and Lantus® (reference) in healthy volunteers. Subjects received subcutaneous administration of the insulin glargine formulation (0.4 U/kg) on two occasions for the test and reference drug, respectively, and a 20% dextrose solution was infused at variable rate to clamp the blood glucose concentrations at 0.3 mmol/L below the subjects’ fasting glucose for 24 h. Taking advantage of the improved sensitivity of the bioanalytical method applied and the solution of the matrix stability problem, the parent insulin glargine was determined in the vast majority of plasma samples using a fully validated UHPLC-MS/MS method. The PK characteristics of the parent insulin glargine were revealed for the first time: after subcutaneous injection, concentrations of the parent insulin glargine increased to a relative high level within 3 h, and then, a relatively flat concentration–time profile lasting for at least 12 h post-dose was observed. For the first time, the pharmacokinetic parameters of the parent insulin glargine were used as endpoints for similarity evaluation, which complied with the regulatory guidance better and made the similarity conclusion more powerful. The ratios of geometric means of all PK and PD endpoints were close to 100.00%. For the PK endpoints (AUC0–24h, Cmax, AUC0–12h, and AUC12–24h of the parent insulin glargine and its metabolite M1), the 90% confidence intervals of geometric mean ratios of test to reference were entirely contained within 80.00%–125.00%. For the PD endpoints [AUCGIR(0–24h), GIRmax, AUCGIR(0–12h), and AUCGIR(12–24h)], the 95% confidence intervals of geometric mean ratios of test to reference were entirely contained within 80.00%–125.00%. Based on the above mentioned results, it can be concluded that the PK and PD characteristics of the biosimilar drug developed by Wanbang are similar to those of Lantus.

A randomized pharmacokinetic and pharmacodynamic trial of two regular human insulins demonstrates bioequivalence in type 1 diabetes and availability of biosimilar insulin may improve access to this medication

AIMS

To compare the pharmacokinetic (PK) and pharmacodynamic (PD) effects and safety of therapeutic dosages of a regular insulin (experimental drug) produced by Bioton S.A. (Warsaw, Poland) versus Humulin® R, a regular insulin (reference drug) produced by Eli Lilly (Indianapolis, Indiana).

MATERIALS AND METHODS

In a single-centre, randomized, double-blinded phase 1 crossover study, we used the manual euglycaemic clamp technique to compare PK and PD profiles between single subcutaneous doses (0.3 units/kg) of the two regular insulins in participants with type 1 diabetes (T1DM) with a washout period of 14 (± 7) days between tests.

RESULTS

We evaluated 56 participants. The mean participant age and body mass index were 32.9 years and 22.9 kg/m² , respectively. The ratios (experimental/reference) of the geometric means of maximum plasma insulin concentration and for plasma insulin area under the curve (AUC) were 0.909 (90% confidence interval [CI] 0.822-1.01) and 0.993 (90% CI 0.944-1.04), respectively. The ratios of the geometric means of maximum glucose infusion rate (GIR) and for GIR AUC were 0.999 (95% CI 0.912-1.09) and 1.04 (95% CI 0.962-1.12), respectively.

CONCLUSIONS

The experimental product regular human insulin and comparator Humulin® R are bioequivalent in patients with T1DM. Wider entry to the pharmaceutical market of affordable, biosimilar regular insulins may substantially improve access to insulin for many socioeconomically disadvantaged patients with diabetes.

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&lt;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 &lt; 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).

Pharmacokinetic and pharmacodynamic equivalence of Biocon's biosimilar Insulin-R with the US-licensed Humulin® R formulation in healthy subjects: Results from the RHINE-1 (Recombinant Human INsulin Equivalence-1) study

AIM

To establish equivalence in the pharmacokinetic (PK) and pharmacodynamic (PD) endpoints between proposed biosimilar Insulin-R (Biocon's Insulin-R) and Humulin® R using the euglycaemic clamp technique in healthy subjects.

MATERIALS AND METHODS

In this phase-1 automated euglycaemic glucose clamp study, 42 healthy subjects were randomized (1:1) to receive a single dose of 0.3 IU/kg of Biocon's Insulin-R and Humulin-R. Plasma insulin concentrations and glucose infusion rates (GIRs) were assessed over 12 hours. Primary PK endpoints were area under the insulin concentration-time curve from 0 to 12 hours (AUC_ins.0-12h ) and maximum insulin concentration (C_ins.max ). Primary PD endpoints were area under the GIR time curve from 0 to 12 hours (AUC_GIR.0-12h ) and maximum GIR (GIR_max ).

RESULTS

Equivalence was demonstrated between Biocon's Insulin-R and Humulin-R for the primary PK and PD endpoints. The 90% confidence intervals were within 80.00% to 125.00% limits. The PK and PD profiles were comparable. There were no significant differences in the safety profiles of the two treatments, and no serious adverse events were reported.

CONCLUSION

PK and PD equivalence was demonstrated between Biocon's Insulin-R and Humulin-R in healthy subjects. Treatment with Biocon's Insulin-R and Humulin-R was well tolerated.

New Clamp-PID Algorithm for Automated Glucose Clamps Improves Clamp Quality

BACKGROUND

In automated glucose clamp experiments, blood glucose (BG) concentrations are kept close to a predefined target level using variable glucose infusion rates (GIRs) determined by implemented algorithms. Clamp quality (ie, the ability to keep BG close to target) highly depends on the quality of these algorithms. We developed a new Clamp algorithm based on the proportional-integral-derivative (PID) approach and compared clamp quality between this and the established Biostator (BS) algorithm.

METHODS

In numerical simulations, the PID-based algorithm was optimized in silico. The optimized Clamp-PID algorithm was tested in in vitro experiments and finally validated in vivo in a small (n = 5) clinical study.

RESULTS

In silico, in vitro, and in vivo experiments showed better clamp quality for the new Clamp-PID algorithm compared with the BS algorithm: precision and absolute control deviation (ACD) decreased from 3.7% to 1.1% and from 2.9 mg/dL to 0.6 mg/dL, respectively, in the numerical simulation. The in vitro validation demonstrated reductions in precision (from 3.3% ± 0.1% (mean ± SD) to 1.4% ± 0.4%) and in ACD (from 2.3 mg/dL ± 0.4 mg/dL to 0.8 mg/dL ± 0.2 mg/dL), respectively. In the clinical study, precision and ACD improved from 6.5% ± 1.3% to 4.0% ± 1.1% and from 3.6 mg/dL ± 0.9 mg/dL to 2.2 mg/dl ± 0.6 mg/dl, respectively. The quality parameter utility did not change.

CONCLUSIONS

The new Clamp-PID algorithm improves the clamp quality parameters precision and ACD versus the BS algorithm.

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.

Pharmacokinetic and pharmacodynamic bioequivalence of biosimilar MYL-1601D with US and European insulin aspart in healthy volunteers: A randomized, double-blind, crossover, euglycaemic glucose clamp study

AIM

To evaluate the pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence (BE) of MYL-1601D biosimilar with originator, NovoLog (Ref-InsAsp-US), and NovoRapid (Ref-InsAsp-EU).

MATERIALS AND METHODS

This was a double-blind, randomized, crossover study that enrolled 71 healthy subjects to receive a single subcutaneous dose (0.2 U/kg) of each formulation under automated euglycaemic clamp conditions (ClampArt, level 81 mg/dL, duration 12 hours postdose). Primary PK endpoints were area under the plasma insulin aspart concentration-time curve from 0 to 12 hours (AUC0-12h ) and maximum plasma insulin aspart concentration (Cmax ). Primary PD endpoints were area under the glucose infusion rate (GIR) time curve from 0 to 12 hours (AUCGIR0-12h ) and maximum GIR (GIRmax ). Insulin aspart in plasma was quantified using immunoaffinity purification followed by ultraperformance liquid chromatography and tandem mass spectrometric detection. The pairwise comparisons of geometric least square mean (LS-mean) ratio for a 90% confidence interval (CI) of primary PK, and 90% CIs (MYL-1601D vs. Ref-InsAsp-US) and 95% CIs (MYL-1601D vs. Ref-InsAsp-EU) of primary PD variables, were to be within 80% to 125% to show BE.

RESULTS

MYL-1601D showed PK BE to both Ref-InsAsp-US (AUC0-12h geometric LS-mean ratio 102.17, 90% CI [100.26; 104.11]; Cmax 106.13 [100.71; 111.85]) and Ref-InsAsp-EU (AUC0-12h 101.84 [100.04; 103.67]; Cmax 105.74 [101.09; 110.60]). Likewise, MYL-1601D showed PD BE to Ref-InsAsp-US (AUCGIR_0-last 99.93; 90% CI [95.74; 104.30]; GIR_max 100.12 [94.46; 106.12]) and Ref-InsAsp-EU (AUCGIR_0-last 96.42; 95% CI [91.17; 101.98]; GIR_max 95.10 [89.37; 101.19]). All three insulin aspart products were well tolerated.

CONCLUSION

MYL-1601D showed BE to Ref-InsAsp-US and Ref-InsAsp-EU with a comparable safety profile.

Pharmacokinetic and pharmacodynamic similarity between SAR341402 insulin aspart and Japan-approved NovoRapid in healthy Japanese subjects

This study compared the pharmacokinetic and glucodynamic profiles of biosimilar SAR341402 insulin aspart to Japan-approved insulin aspart (NovoRapid) in healthy Japanese males. In this single-center, randomized, double-blind, single-dose, two-period, crossover study, subjects received 0.3 U/kg of SAR341402 or NovoRapid before undergoing a 10 h euglycemic clamp procedure. Plasma insulin aspart concentrations and blood glucose levels were measured, and glucose infusion rates (GIRs) were assessed. Primary endpoints were maximum plasma insulin aspart concentration (INS-C_max), area under the plasma insulin concentration–time curve to the last quantifiable concentration (INS-AUC_last), area under the GIR–time curve during the clamp (GIR-AUC_0–10 h), and maximum GIR (GIR_max). Forty subjects were randomized with 39 completing both treatment periods. Pharmacokinetic exposure showed a mean ratio between products of 1.00 (90% confidence interval [CI] 0.94–1.05) for INS-C_max and 1.02 (90% CI 1.00–1.04) for INS-AUC_last. Glucodynamic activity showed a mean ratio between products of 1.00 (95% CI 0.93–1.06) for GIR-AUC_0–10 h and 1.01 (95% CI 0.95–1.08) for GIR_max. The 90% CIs for pairwise treatment ratios were within the predefined equivalence range of 0.80–1.25. Both treatments were well tolerated. We concluded that similar pharmacokinetic exposure and glucodynamic potency were shown for SAR341402 and NovoRapid in healthy Japanese males.

Similar pharmacokinetics and pharmacodynamics of a new biosimilar and reference insulin aspart in healthy Chinese males

Insulin aspart (IAsp) is one of the main therapies used to control blood glucose after a meal. This study aimed to compare the pharmacokinetics (PK) and pharmacodynamics (PD) of 2 rapid-acting IAsp products: a new IAsp biosimilar (RD10046) and NovoRapid. In a single-center, randomized, single-dose, 2-period, crossover, euglycemic clamp study (registry number: CTR20180517, registration date: 2018-05-30), healthy Chinese males were randomized to receive 0.2 U/kg of the IAsp biosimilar RD10046 and NovoRapid under fasted conditions on two separate occasions. PK and PD were assessed for up to 10 h. Of the 30 randomized subjects, all 30 completed both treatment periods. The PK (area under the curve [AUC] of total IAsp; maximum observed IAsp concentration [C_max]) and PD (maximum glucose infusion rate [GIR_max]; total glucose infusion during the clamp [AUC_GIR,0–10h]) were similar between the new IAsp biosimilar RD10046 and NovoRapid. In all cases, the 90% CIs for the ratios of the geometric means were completely contained in the prespecified acceptance limits of 0.80–1.25. No hypoglycemic events, allergic reactions, or local injection adverse reactions occurred in this trial. We concluded that the studied IAsp biosimilar (RD10046) was bioequivalent to NovoRapid.

Hyperinsulinaemic-hypoglycaemic glucose clamps in human research: a systematic review of the literature

AIMS/HYPOTHESIS

The hyperinsulinaemic-hypoglycaemic glucose clamp technique has been developed and applied to assess effects of and responses to hypoglycaemia under standardised conditions. However, the degree to which the methodology of clamp studies is standardised is unclear. This systematic review examines how hyperinsulinaemic-hypoglycaemic clamps have been performed and elucidates potential important differences.

METHODS

A literature search in PubMed and EMBASE was conducted. Articles in English published between 1980 and 2018, involving adults with or without diabetes, were included.

RESULTS

A total of 383 articles were included. There was considerable variation in essential methodology of the hypoglycaemic clamp procedures, including the insulin dose used (49-fold difference between the lowest and the highest rate), the number of hypoglycaemic steps (range 1-6), the hypoglycaemic nadirs (range 2.0-4.3 mmol/l) and the duration (ranging from 5 to 660 min). Twenty-seven per cent of the articles reported whole blood glucose levels, most venous levels. In 70.8% of the studies, a dorsal hand vein was used for blood sampling, with some form of hand warming to arterialise venous blood in 78.8% of these. Key information was missing in 61.9% of the articles.

CONCLUSIONS/INTERPRETATION

Although the hyperinsulinaemic-hypoglycaemic clamp procedure is considered the gold standard to study experimental hypoglycaemia, a uniform standard with key elements on how to perform these experiments is lacking. Methodological differences should be considered when comparing results between hypoglycaemic clamp studies.

PROSPERO REGISTRATION

This systematic review is registered in PROSPERO (CRD42019120083).

Precision and accuracy of hyperglycemic clamps in a multicenter study

Application of glucose clamp methodologies in multicenter studies brings challenges for standardization. The Restoring Insulin Secretion (RISE) Consortium implemented a hyperglycemic clamp protocol across seven centers using a combination of technical and management approaches to achieve standardization. Two-stage hyperglycemic clamps with glucose targets of 200 mg/dL and >450 mg/dL were performed utilizing a centralized spreadsheet-based algorithm that guided dextrose infusion rates using bedside plasma glucose measurements. Clamp operators received initial and repeated training with ongoing feedback based on surveillance of clamp performance. The precision and accuracy of the achieved stage-specific glucose targets were evaluated, including differences by study center. We also evaluated robustness of the method to baseline physiologic differences and on-study treatment effects. The RISE approach produced high overall precision (3%-9% variance in achieved plasma glucose from target at various times across the procedure) and accuracy (SD < 10% overall). Statistically significant but numerically small differences in achieved target glucose concentrations were observed across study centers, within the magnitude of the observed technical variability. Variation of the achieved target glucose over time in placebo-treated individuals was low (<3% variation), and the method was robust to differences in baseline physiology (youth vs. adult, IGT vs. diabetes status) and differences in physiology induced by study treatments. The RISE approach to standardization of the hyperglycemic clamp methodology across multiple study centers produced technically excellent standardization of achieved glucose concentrations. This approach provides a reliable method for implementing glucose clamp methodology across multiple study centers.NEW & NOTEWORTHY The Restoring Insulin Secretion (RISE) study centers undertook hyperglycemic clamps using a simplified methodology and a decision guidance algorithm implemented in an easy-to-use spreadsheet. This approach, combined with active management including ongoing central data surveillance and routine feedback to study centers, produced technically excellent standardization of achieved glucose concentrations on repeat studies within and across study centers.

Pharmacokinetics and Pharmacodynamics of Three Different Formulations of Insulin Aspart: A Randomized, Double-Blind, Crossover Study in Men With Type 1 Diabetes

OBJECTIVE

To investigate the pharmacokinetic and pharmacodynamic properties and safety of a novel formulation of insulin aspart (AT247) versus two currently marketed insulin aspart formulations (NovoRapid [IAsp] and Fiasp [faster IAsp]).

RESEARCH DESIGN AND METHODS

This single-center, randomized, double-blind, three-period, crossover study was conducted in 19 men with type 1 diabetes, receiving single dosing of trial products (0.3 units/kg) in a random order on three visits. Pharmacokinetics and pharmacodynamics were assessed during a euglycemic clamp lasting up to 8 h.

RESULTS

Onset of insulin appearance was earlier for AT247 compared with IAsp (-12 min [95% CI -14; -8], P = 0.0004) and faster IAsp (-2 min [-5; -2], P = 0.0003). Onset of action was accelerated compared with IAsp (-23 min [-37; -15], P = 0.0004) and faster IAsp (-9 min [-11; -3], P = 0.0006). Within the first 60 min, a higher exposure was observed for AT247 compared with IAsp by the area under the curve (AUC) glucose infusion rate (GIR) from 0 to 60 min (AUC_Asp0-60min: treatment ratio vs. IAsp 2.3 [1.9; 2.9] vs. faster IAsp 1.5 [1.3; 1.8]), which was underpinned by a greater early glucose-lowering effect (AUC_GIR,0-60min: treatment ratio vs. IAsp 2.8 [2.0; 5.5] vs. faster IAsp 1.7 [1.3; 2.3]). Furthermore, an earlier offset of exposure was observed for AT247 compared with IAsp (-32 min [-58; -15], P = 0.0015) and faster IAsp (-27 min [-85; -15], P = 0.0017), while duration of the glucose-lowering effect, measured by time to late half-maximum effect, did not differ significantly.

CONCLUSIONS

AT247 exhibited an earlier insulin appearance, exposure, and offset, with corresponding enhanced early glucose-lowering effect compared with IAsp and faster IAsp. It therefore represents a promising candidate in the pursuit for second-generation prandial insulin analogs to improve postprandial glycemic control.

Oscillations of C-peptide in the euglycemic clamp and their effect on the pharmacodynamic assessment of insulin preparations

C-peptide should be continuously suppressed. However, increased postdosing C-peptide is not an uncommon phenomenon in euglycemic clamp studies involving healthy participants. This study aimed to determine the extent to which the postdosing C-peptide increases from the baseline that could affect the accuracy of glucodynamics in euglycemic clamp studies involving healthy subjects. First, 10 healthy males underwent a 10-h euglycemic clamp without exogenous insulin administration to obtain a reference interval (RI) for the ratio of C-peptide after 0 min (CP_t ) to baseline C-peptide (CP₀ ). Then, the data from a pharmacokinetic and pharmacodynamic study of insulin aspart (IAsp) were analyzed, and 70 eligible clamps were grouped by CP_t /CP₀ : group A ([CP_t /CP₀ ]_max   > upper limit of RI), group B (1<[CP_t /CP₀ ]_max  ≤ upper limit of RI), and group C ([CP_t /CP₀ ]_max  ≤ 1). The differences in basal and clamped blood glucose, CP_t /CP₀ , and the pharmacokinetics and pharmacodynamics of IAsp were compared, and the relationship between elevated CP_t and the accuracy of pharmacodynamics was analyzed. The RI of CP_t /CP₀ was 22.7%-152.1%; 1.5 × baseline might be a ceiling for the increase in CP_t under stable conditions. The maximum glucose infusion rate (GIR) in group A tended to be higher than that in group B or C (P_{for trend}  = 0.033). The AUC_GIR,0-10h in groups A, B, and C was 1983 ± 650,1682 ± 454, and 1479 ± 440 mg/kg (P = 0.047), respectively, under comparable IAsp exposure. No intergroup difference was detected in clamped glucose, IAsp dose, or body mass index. In conclusion, postdosing C-peptide over 1.5× baseline indicates insufficient inhibition of endogenous insulin secretion, which could compromise the pharmacodynamics of insulin preparations.

Single-Dose Euglycemic Clamp Study Demonstrating Pharmacokinetic and Pharmacodynamic Similarity Between SAR341402 Insulin Aspart and US- and EU-Approved Versions of Insulin Aspart in Subjects with Type 1 Diabetes

Background: The objective of this study was to demonstrate the pharmacokinetic and pharmacodynamic similarity among SAR341402 insulin aspart biosimilar/follow-on product, United States-sourced insulin aspart (NovoLog®), and European Union-sourced insulin aspart (NovoRapid®). Materials and Methods: This was a single-center, randomized, double-blind, 3-treatment, 3-period, single-dose, crossover euglycemic study (NCT03202875) in 30 adult male subjects with type 1 diabetes (T1D). Subjects received 0.3 U/kg of each treatment under fasted conditions and underwent a 12-h euglycemic clamp technique to assess pharmacokinetic and pharmacodynamic activity for up to 12 h. Primary endpoints were area under the plasma insulin concentration-time curve from time zero to the last quantifiable concentration (INS-AUClast), and extrapolated to infinity (INS-AUCinf), maximum plasma insulin concentration (INS-Cmax), and the area under the body weight-standardized glucose infusion rate (GIR)-time curve from 0 to 12 hours (GIR-AUC0-12h) among the three treatments. GIRmax was the main secondary endpoint. Results: Of the 30 subjects randomized, 29 completed all 3 treatment periods. Pharmacokinetic and pharmacodynamic profiles were similar in all groups. The extent of exposure (INS-Cmax, INS-AUClast, and INS-AUCinf) and glucodynamic activity (GIR-AUC0-12h, GIRmax) was similar among the three treatments. The corresponding 90% confidence intervals for pairwise treatment ratios were completely contained within the limits of 80%-125%. SAR341402 was well tolerated. Conclusions: The present study demonstrated similar pharmacokinetic exposure profiles and glucodynamic potency among SAR341402, NovoLog, and NovoRapid in subjects with T1D, supporting further clinical evaluation of SAR341402 as a biosimilar/follow-on product.

The Effects of Self-Control on Glucose Utilization in a Hyperinsulinemic Euglycemic Glucose Clamp

Abstract. Background. The glucose hypothesis of self-control posits that acts of self-control may draw upon glucose as a source of energy, leading to a decrease in blood glucose levels after exerting self-control, mirroring the temporary depletion of self-control, but supporting evidence is mixed and inconclusive. This might partly be due to using methods that are not suitable to reliably quantify glucose utilization. Aims. We aimed at examining whether self-control exertion leads to an increase in glucose utilization. Method. In a sample of N = 30 healthy participants (50% women, age 26.5 ± 3.5 years) we combined a hyperinsulinemic euglycemic glucose clamp (a well-established and validated procedure in experimental endocrinology to reliably quantify systemic glucose utilization) with a standard self-control dual-task paradigm. In the first task, the experimental group completed a variation of a paper-and-pencil crossing out letter task (COLT) that demanded self-control; the control group completed a variation of the COLT that did not demand self-control. The second task for both groups was a computerized two-color word Stroop which demanded self-control. Results. We did not find a significant main effect for time, nor a time × group interaction with respect to glucose utilization, which indicates that glucose utilization did not differ significantly over time or between groups. Limitations. Due to the time-consuming and complicated clamp method, our sample was rather small. Conclusion. Our results revealed little evidence for the notion that self-control efforts are associated with a relevant increase in peripheral glucose utilization.

Fast-acting insulin aspart in people with type 2 diabetes: Earlier onset and greater initial exposure and glucose-lowering effect compared with insulin aspart

AIMS

To investigate the pharmacokinetic/pharmacodynamic properties of fast-acting insulin aspart (faster aspart) versus insulin aspart (IAsp) in people with type 2 diabetes (T2D).

MATERIALS AND METHODS

In a randomized, double-blind, crossover design, 61 people with T2D usually treated with insulin ± oral antidiabetic drug(s) received single-dose faster aspart and IAsp (0.3 U/kg) on separate visits. Blood samples for pharmacokinetic assessment were collected frequently until 12 hours post-dose. Glucose-lowering effect was determined in a euglycaemic clamp lasting up to 12 hours post-dose (target 5.0 mmol/L).

RESULTS

The serum IAsp pharmacokinetic profile and glucose-lowering effect profile were shifted to the left for faster aspart versus IAsp. Least squares mean (± SE) onset of appearance was 3.3 ± 0.3 minutes for faster aspart, which was 1.2 minutes earlier than for IAsp (95% confidence interval [CI] -1.8;-0.5; P = .001). Onset of action for faster aspart was 8.9 minutes earlier (95% CI -12.1;-5.7; P < .001) than for IAsp. During the first 30 minutes after dosing, 89% larger IAsp exposure (ratio faster aspart/IAsp 1.89 [95% CI 1.56;2.28]; P < .001) and 147% greater glucose-lowering effect (2.47 [95% CI 1.58;6.22]; P < .001) were observed for faster aspart compared with IAsp. Offset of exposure (time to 50% of maximum IAsp concentration in the late part of the pharmacokinetic profile) occurred earlier for faster aspart (difference faster aspart - IAsp -36.4 minutes [95% CI -55.3;-17.6]; P < .001). The treatment difference of faster aspart - IAsp in offset of glucose-lowering effect (time to 50% of maximum glucose infusion rate in the late part of the glucose infusion rate profile) was -14.4 minutes (95% CI -34.4;5.5; P = .152).

CONCLUSIONS

In people with T2D, faster aspart was associated with earlier onset and greater initial exposure and glucose-lowering effect compared with IAsp, as previously shown in people with type 1 diabetes.

Considering Blood Dilution improves the Precision of Continuous Whole Blood Glucose Measurements

BACKGROUND

One major advantage of automated over manual clamps are continuous measurements of blood glucose concentrations (BG) allowing frequent adaptations in glucose infusion rates (GIR). However, BG measurements might be affected by changes in blood dilution. ClampArt®, a modern automated clamp device, corrects BG measurements for blood dilution, but the impact of this correction is unclear.

METHODS

The authors performed a retrospective analysis of BG during glucose clamps comparing values with a fixed dilution factor with those corrected for the actual blood dilution.

RESULTS

Clamp quality substantially improved with the consideration of blood dilution: Mean accuracy fell from 8.1% ± 2.9% to 4.1% ± 0.8%, precision improved from 9.6 ± 3.6 mg/dl to 3.7 ± 1.3 mg/dl and control deviation from -2.6 ± 4.2 mg/dl to 0.2 ± 0.2 mg/dl.

CONCLUSIONS

Correcting continuous BG measurements for blood dilution significantly increases BG measurement and clamp quality.

BioChaperone Lispro versus faster aspart and insulin aspart in patients with type 1 diabetes using continuous subcutaneous insulin infusion: A randomized euglycemic clamp study

We investigated the pharmacodynamics (PD) and pharmacokinetics (PK) of BioChaperone insulin Lispro (BCLIS), faster insulin aspart (FIA) and insulin aspart (ASP) in patients with type 1 diabetes using an insulin pump. In this randomized, double-blind, three-way crossover glucose clamp study, 43 patients received a bolus dose of each insulin (0.15 U/kg) in addition to a basal rate (0.01 U/kg/h), delivered via an insulin pump. With BCLIS, the AUC-GIR,0-60 minutes (primary endpoint) was improved compared to ASP (least square means ratio, 1.63; 95% CI, 1.44-1.88; P < 0.0001) and was similar compared to FIA (least square means ratio, 1.06; 95% CI, 0.94-1.18; P = 0.4609). BCLIS showed faster-on PD (t_{early0.5GIRmax} ) than ASP and faster-off PD (t_{late0.5GIRmax} ) than both FIA and ASP. BCLIS also demonstrated significantly higher early exposure (AUCins, 0-60 minutes) and lower late exposure (AUCins,120-600 minutes) than both other insulins. In patients with type 1 diabetes using an insulin pump, BCLIS better mimics prandial insulin secretion and action than ASP and shows a faster off-PD than FIA.

Artificial Pancreas Systems for People With Type 2 Diabetes: Conception and Design of the European CLOSE Project

In the last 10 years tremendous progress has been made in the development of artificial pancreas (AP) systems for people with type 1 diabetes (T1D). The pan-European consortium CLOSE (Automated Glu cose Contro l at H ome for People with Chronic Disea se) is aiming to develop integrated AP solutions (APplus) tailored to the needs of people with type 2 diabetes (T2D). APplus comprises a product and service package complementing the AP system by obligatory training as well as home visits and telemedical consultations on demand. Outcome predictors and performance indicators shall help to identify people who could benefit most from AP usage and facilitate the measurement of AP impact in diabetes care. In a first step CLOSE will establish a scalable APplus model case working at the interface between patients, homecare service providers, and payers in France. CLOSE will then scale up APplus by pursuing geographic distribution, targeting additional audiences, and enhancing AP functionalities and interconnectedness. By being part of the European Institute of Innovation and Technology (EIT) Health public-private partnership, CLOSE is committed to the EIT "knowledge triangle" pursuing the integrated advancement of technology, education, and business creation. Putting stakeholders, education, and impact into the center of APplus advancement is considered key for achieving wide AP use in T2D care.

Day-to-Day and Within-Day Variability in Glucose-Lowering Effect Between Insulin Degludec and Insulin Glargine (100 U/mL and 300 U/mL): A Comparison Across Studies

BACKGROUND

Insulin degludec (IDeg) has significantly lower day-to-day and within-day variability compared to insulin glargine (IGlar) 100U/mL (U100) and 300U/mL (U300). Here, we report post hoc assessments to confirm the robustness of these observations while accounting for potential experimental confounders.

METHODS

Two euglycemic clamp studies in type 1 diabetes patients, comparing IDeg to IGlar-U100 (Study A, parallel design, 54 patients; Study B, crossover, 22 patients) and one study comparing IDeg to IGlar-U300 (Study C, crossover, 57 patients), all dosed at 0.4U/kg, were evaluated. Pharmacodynamic parameters were assessed at steady state from glucose infusion rate (GIR) profiles following three 24-hour euglycemic clamps in Studies A (162 clamps) and C (342 clamps), and one 42-hour clamp in Study B (44 clamps).

RESULTS

Pooled data (Studies A and B) showed that IDeg had an even distribution of glucose-lowering effect over the 24-hour dosing interval that was consistent with Study C. IGlar-U100 showed a constant decrease in glucose-lowering effect over 24 hours while IGlar-U300 had a lower effect in the middle of the dosing interval (6-18 hours). Relative within-day variability of IDeg was 40% and 37% lower than IGlar-U100 and -U300, respectively. Exclusion of profiles with low response in Study C (19/342 clamps) did not impact the difference in the distribution of glucose-lowering effect or within-day variability. Day-to-day variability was significantly lower with IDeg compared to IGlar-U100 and -U300 based on smoothed and unsmoothed GIR data.

CONCLUSIONS

Significantly lower relative within-day and day-to-day variability was confirmed irrespective of experimental considerations for IDeg compared to IGlar-U100 and IGlar-U300.

Pharmacokinetic and Pharmacodynamic Properties of Faster-Acting Insulin Aspart versus Insulin Aspart Across a Clinically Relevant Dose Range in Subjects with Type 1 Diabetes Mellitus

Background

Absorption of current rapid-acting insulins is too slow for patients with diabetes mellitus to achieve optimal postprandial glucose control. Faster-acting insulin aspart (faster aspart) is insulin aspart in a new formulation with faster early absorption. We compared the pharmacokinetic/pharmacodynamic properties of faster aspart and insulin aspart across a clinically relevant dose range.

Methods

In this randomised, double-blind, crossover trial, 46 subjects with type 1 diabetes mellitus received single subcutaneous doses of faster aspart and insulin aspart at 0.1, 0.2 (repeated three times to estimate within-subject variability) and 0.4 U/kg in a euglycaemic clamp setting (target 5.5 mmol/L).

Results

Consistently for the three doses, faster aspart demonstrated faster onset and greater early absorption and glucose-lowering effect versus insulin aspart. Across all three doses, onset of appearance occurred approximately twice as fast (approximately 5 min earlier) and early insulin exposure (AUC_{IAsp,0–30min}) was approximately 1.5- to 2-fold greater for faster aspart versus insulin aspart. Likewise, onset of action occurred approximately 5 min faster and early glucose-lowering effect (AUC_{GIR,0–30min}) was approximately 1.5- to 2-fold larger for faster aspart versus insulin aspart. Relative bioavailability was approximately 100% and total glucose-lowering effect was similar for faster aspart versus insulin aspart. Dose–concentration and dose–response relationships were comparable between faster aspart and insulin aspart. Within-subject variability in glucose-lowering effect was low for faster aspart (coefficient of variation approximately 20%) and not significantly different from insulin aspart.

Conclusion

The faster onset and greater early insulin exposure and glucose-lowering effect with faster aspart versus insulin aspart are preserved across a broad range of doses and consistently observed from day to day.

ClinicalTrials.gov identifier

NCT02033239.

Electronic supplementary material

The online version of this article (doi:10.1007/s40262-016-0473-5) contains supplementary material, which is available to authorized users.

Single-dose euglycaemic clamp studies demonstrating pharmacokinetic and pharmacodynamic similarity between MK-1293 insulin glargine and originator insulin glargine (Lantus) in subjects with type 1 diabetes and healthy subjects

AIMS

MK-1293 is an insulin glargine that has an amino acid sequence identical to that of Lantus, the originator insulin glargine. Two euglycaemic clamp studies, 1 in subjects with type 1 diabetes (T1D) and 1 in healthy subjects, were conducted to demonstrate pharmacokinetic (PK) and pharmacodynamic (PD) similarity between MK-1293 and Lantus commercially procured in both the European Union (EU-Lantus) and the USA (US-Lantus).

MATERIALS AND METHODS

Both studies were single-dose, randomized, double-blind, single-centre, crossover studies with ≥7 days between dosing periods. A 2-treatment, 4-period replicate crossover study in T1D subjects (N = 76) compared the PK and PD of MK-1293 to EU-Lantus for 30 hours after dosing. A 3-period crossover study in healthy subjects (N = 109) compared the PK and PD of MK-1293, EU-Lantus and US-Lantus for 24 hours after dosing. In both studies, all subjects received single 0.4 units/kg subcutaneous doses of MK-1293 or Lantus in all dosing periods. Pharmacokinetic assessment was based on LC-MS/MS-based measurement of the major insulin glargine metabolite (M1) and PD was characterized using the euglycaemic clamp platform.

RESULTS

In both studies, pre-specified similarity criteria were met between MK-1293 and Lantus for comparison of PK (AUC0-24 and Cmax of M1) and PD (GIR-AUC0-24 , GIR-AUC0-12 , GIR-AUC12-24 , and GIRmax ) primary endpoints. All treatments were well tolerated.

CONCLUSION

Based on comparative assessment in both T1D and healthy subjects, it can be concluded that the PK and PD properties of MK-1293 are highly similar to those of Lantus. (ClinicalTrials.gov: NCT02059174).

Computer Simulation Model to Train Medical Personnel on Glucose Clamp Procedures

OBJECTIVE

A glucose clamp procedure is the most reliable way to quantify insulin pharmacokinetics and pharmacodynamics, but skilled and trained research personnel are required to frequently adjust the glucose infusion rate. A computer environment that simulates glucose clamp experiments can be used for efficient personnel training and development and testing of algorithms for automated glucose clamps.

METHODS

We built 17 virtual healthy subjects (mean age, 25±6 years; mean body mass index, 22.2±3 kg/m²), each comprising a mathematical model of glucose regulation and a unique set of parameters. Each virtual subject simulates plasma glucose and insulin concentrations in response to intravenous insulin and glucose infusions. Each virtual subject provides a unique response, and its parameters were estimated from combined intravenous glucose tolerance test-hyperinsulinemic-euglycemic clamp data using the Bayesian approach. The virtual subjects were validated by comparing their simulated predictions against data from 12 healthy individuals who underwent a hyperglycemic glucose clamp procedure.

RESULTS

Plasma glucose and insulin concentrations were predicted by the virtual subjects in response to glucose infusions determined by a trained research staff performing a simulated hyperglycemic clamp experiment. The total amount of glucose infusion was indifferent between the simulated and the real subjects (85±18 g vs. 83±23 g; p=NS) as well as plasma insulin levels (63±20 mU/L vs. 58±16 mU/L; p=NS).

CONCLUSIONS

The virtual subjects can reliably predict glucose needs and plasma insulin profiles during hyperglycemic glucose clamp conditions. These virtual subjects can be used to train personnel to make glucose infusion adjustments during clamp experiments.

A Comparison of Pharmacokinetic and Pharmacodynamic Properties Between Faster-Acting Insulin Aspart and Insulin Aspart in Elderly Subjects with Type 1 Diabetes Mellitus

Background

Due to population aging, an increasing number of elderly patients with diabetes use insulin. It is therefore important to investigate the characteristics of new insulins in this population. Faster-acting insulin aspart (faster aspart) is insulin aspart (IAsp) in a new formulation with faster absorption. This study investigated the pharmacological properties of faster aspart in elderly subjects with type 1 diabetes mellitus (T1DM).

Methods

In a randomised, double-blind, two-period crossover trial, 30 elderly (≥65 years) and 37 younger adults (18–35 years) with T1DM received single subcutaneous faster aspart or IAsp dosing (0.2 U/kg) and underwent an euglycaemic clamp (target 5.5 mmol/L) for up to 12 h.

Results

The pharmacokinetic and pharmacodynamic time profiles were left-shifted for faster aspart versus IAsp. In each age group, onset of appearance occurred approximately twice as fast (~3 min earlier) and early exposure (area under the concentration–time curve [AUC] for serum IAsp from time zero to 30 min [AUC_{IAsp,0-30 min}]) was greater (by 86% in elderly and 67% in younger adults) for faster aspart than for IAsp. Likewise, onset of action occurred 10 min faster in the elderly and 9 min faster in younger adults, and early glucose-lowering effect (AUC for the glucose infusion rate [GIR] from time zero to 30 min [AUC_{GIR,0-30 min}]) was greater (by 109%) for faster aspart than for IAsp in both age groups. Total exposure (AUC_IAsp,0-t) and the maximum concentration (C_max) for faster aspart were greater (by 30 and 28%, respectively) in elderly than in younger adults. No age group differences were seen for the total (AUC_GIR,0-t) or maximum (GIR_max) glucose-lowering effect.

Conclusion

This study demonstrated that the ultra-fast pharmacological properties of faster aspart are similar in elderly subjects and younger adults with T1DM.

ClinicalTrials.gov Identifier: NCT02003677.

Electronic supplementary material

The online version of this article (doi:10.1007/s40266-016-0418-6) contains supplementary material, which is available to authorized users.

Insulin degludec: Lower day-to-day and within-day variability in pharmacodynamic response compared with insulin glargine 300 U/mL in type 1 diabetes

AIM

To compare day-to-day and within-day variability in glucose-lowering effect between insulin degludec (IDeg) and insulin glargine 300 U/mL (IGlar-U300) in type 1 diabetes.

MATERIALS AND METHODS

In this double-blind, crossover study, patients were randomly assigned to 0.4 U/kg of IDeg or IGlar-U300 once daily for two treatment periods lasting 12 days each. Pharmacodynamic variables were assessed at steady-state from the glucose infusion rate profiles of three 24-hour euglycaemic glucose clamps (days 6, 9 and 12) during each treatment period.

RESULTS

Overall, 57 patients completed both treatment periods (342 clamps). The potency of IGlar-U300 was 30% lower than IDeg (estimated ratio 0.70, 95% confidence interval [CI] 0.61; 0.80; P  < .0001). The distribution of glucose-lowering effect was stable across 6-hour intervals (24%-26%) for IDeg, while IGlar-U300 had greater effects in the first (35%) and last (28%) intervals compared with 6 to 12 hours (20%) and 12 to 18 hours (17%). Within-day variability (relative fluctuation) was 37% lower with IDeg than with IGlar-U300 (estimated ratio IDeg/IGlar-U300: 0.63, 95% CI 0.54; 0.73; P  < .0001). The day-to-day variability in glucose-lowering effect with IDeg was approximately 4 times lower than IGlar-U300 (variance ratio IGlar-U300/IDeg: 3.70, 95% CI 2.42; 5.67; P  < .0001). The day-to-day variability in glucose-lowering effect assessed in 2-hour intervals was consistently low with IDeg over 24 hours, but steadily increased with IGlar-U300 to a maximum at 10 to 12 hours and 12 to 14 hours after dosing (variance ratios 12.4 and 11.4, respectively).

CONCLUSION

IDeg has lower day-to-day and within-day variability than IGlar-U300 and a more stable glucose-lowering effect, which might facilitate titration and enable tighter glycaemic control with a reduced risk of hypoglycaemia.

Similar pharmacokinetics and pharmacodynamics of rapid-acting insulin lispro products SAR342434 and US- and EU-approved Humalog in subjects with type 1 diabetes

AIM

To compare the pharmacokinetics (PK) and pharmacodynamics (PD) of 3 rapid-acting insulin lispro products: SAR342434 solution, United States (US)-approved Humalog and European Union (EU)-approved Humalog.

METHODS

In a single-centre, randomized, double-blind, 3-treatment, 3-period, 6-sequence, crossover, euglycaemic clamp study (NCT02273258), adult male subjects with type 1 diabetes were randomized to receive 0.3 U/kg of SAR342434 solution, US-approved and EU-approved Humalog under fasted conditions. PK and PD (glucose infusion rate [GIR]) were assessed up to 12 hours.

RESULTS

Of the 30 subjects randomized, 28 completed all 3 treatment periods. Mean concentration and GIR vs time profiles were similar for all 3 products. Exposure (INS-C_max , INS-AUC_last and INS-AUC) and activity (GIR_max and GIR-AUC_0-12h ) of SAR342434, US-approved and EU-approved Humalog were similar in all comparisons (point estimates of treatment ratios, 0.95-1.03 for PK parameters and 1.00-1.07 for PD parameters), with 90% confidence intervals for the ratios of geometric least squares means within the pre-specified bioequivalence limit (0.80-1.25) and no significant differences in time-related parameters. Within-subject variability of exposure and activity was low across the 3 clamps, indicating high day-to-day reproducibility in clamp performance, irrespective of the individual product. Adverse events were similar for all 3 products. No safety concerns were noted in vital signs or in laboratory and electrocardiogram data.

CONCLUSIONS

The results of this study demonstrate similarity in insulin lispro exposure profiles and PD activity of SAR342434 solution to both US- and EU-approved Humalog, and between both US- and EU-approved Humalog, supporting the use of SAR342434 solution for injection as a follow-on product.

Novel hepato-preferential basal insulin peglispro (BIL) does not differentially affect insulin sensitivity compared with insulin glargine in patients with type 1 and type 2 diabetes

AIMS

Basal insulin peglispro (BIL) is a novel PEGylated basal insulin with a flat pharmacokinetic and glucodynamic profile and reduced peripheral effects, which results in a hepato-preferential action. In Phase 3 trials, patients with T1DM treated with BIL had lower prandial insulin requirements, yet improved prandial glucose control, relative to insulin glargine (GL). We hypothesized that this may be because of an enhanced sensitivity to prandial insulin with BIL resulting from lower chronic peripheral insulin action.

MATERIALS AND METHODS

Two open-label, randomized, 2-period crossover clinical studies were conducted in 28 patients with T1DM and 24 patients with T2DM. In each study period, patients received once-daily, individualized, stable, subcutaneous doses of BIL or GL for 5 weeks before a euglycaemic 2-step hyperinsulinemic clamp procedure (with [6,6- ² H₂ ]-glucose in 12 of the patients with T1DM). M-values were derived from the clamp procedure for all patients, with rate of glucose appearance (Ra) and disappearance (Rd) and insulin sensitivity index (SI) determined from the clamps with [6,6- ² H₂ ]-glucose.

RESULTS

There were no statistically significant differences between BIL and GL in key measures of hepatic (% Ra suppression during the low-dose insulin infusion; 78.7% with BIL, 81.8% with GL) or peripheral (M-value and M/I during the high-dose insulin infusion, Rd and SI) insulin sensitivity in patients with T1DM or T2DM.

CONCLUSIONS

The need to reduce prandial insulin observed with BIL during phase 3 trials cannot be explained by the differential effects of BIL and GL on sensitivity to prandial insulin in either T1DM or T2DM.

Effects on α- and β-cell function of sequentially adding empagliflozin and linagliptin to therapy in people with type 2 diabetes previously receiving metformin: An exploratory mechanistic study

AIMS

To investigate the effect of sequential treatment escalation with empagliflozin and linagliptin on laboratory markers of α- and β-cell function in people with type 2 diabetes mellitus (T2DM) insufficiently controlled on metformin monotherapy.

RESEARCH DESIGN AND METHODS

A total of 44 people with T2DM received 25 mg empagliflozin for a duration of 1 month in an open-label fashion (treatment period 1 [TP1]). Thereafter, they were randomized to a double-blind add-on therapy with linagliptin 5 mg or placebo (treatment period 2 [TP2]) for 1 additional month. α- and β-cell function was assessed using a standardized liquid meal test and an intravenous (i.v.) glucose challenge. Efficacy measures comprised the areas under the curve for glucose, insulin, proinsulin and glucagon after the liquid meal test and the assessment of fast and late-phase insulin release after an i.v. glucose load with a subsequent hyperglycaemic clamp.

RESULTS

Empagliflozin reduced fasting and postprandial plasma glucose levels, associated with a significant reduction in postprandial insulin levels and an improvement in the conversion rate of proinsulin (TP1). The addition of linagliptin during TP2 further improved postprandial glucose levels, probably as a result of a marked reduction in postprandial glucagon concentrations (TP2). The insulin response to an i.v. glucose load increased during treatment with empagliflozin (TP1), and further improved after the addition of linagliptin (TP2).

CONCLUSION

After metformin failure, sequential treatment escalation with empagliflozin and linagliptin is an attractive treatment option because of the additive effects on postprandial glucose control, probably mediated by complementary effects on α- and β-cell function.

Pharmacological properties of faster-acting insulin aspart vs insulin aspart in patients with type 1 diabetes receiving continuous subcutaneous insulin infusion: A randomized, double-blind, crossover trial

AIM

To evaluate the pharmacological characteristics of faster-acting insulin aspart (faster aspart) compared with insulin aspart (IAsp) during continuous subcutaneous insulin infusion (CSII).

METHODS

In this randomized, double-blind, crossover trial, 48 men and women aged 18 to 64 years with type 1 diabetes mellitus (T1DM) received faster aspart and IAsp as a 0.15 U/kg bolus dose via CSII, on top of a basal rate (0.02 U/kg/h), in a glucose clamp setting (target 5.5 mmol/L).

RESULTS

After a CSII bolus dose, the pharmacokinetic/pharmacodynamic profiles for faster aspart were left-shifted compared with those for IAsp. For faster aspart vs IAsp, the early glucose-lowering effect (area under the curve for glucose infusion rate [GIR]0-30min ) was approximately 2-fold higher (least squares means 24.9 vs 11.4 mg/kg; estimated ratio faster aspart/IAsp 2.18, 95% confidence interval [CI] [1.33; 5.04]; P = .002), onset of glucose-lowering effect (time to early 50% of maximum GIR) occurred 11.1 minutes earlier (41.1 vs 52.3 minutes; 95% CI faster aspart - IAsp [-15.4; -6.9]; P<.001), and offset of glucose-lowering effect (time to late 50% of maximum GIR) occurred 24.0 minutes earlier (214.7 vs 238.7 minutes; 95% CI [-38.9; -9.1]; P=.002). Likewise, significantly greater early exposure and significantly earlier onset and offset of exposure were observed for faster aspart vs IAsp. Faster aspart and IAsp were both well tolerated.

CONCLUSIONS

In patients with T1DM using CSII, faster aspart better mimics the endogenous prandial insulin secretion and action than does IAsp. Faster aspart therefore has the potential to provide clinical benefits over current rapid-acting insulins in the insulin pump setting.

Improved Algorithm for Automated Glucose Clamps

BACKGROUND

In glucose clamp experiments, blood glucose concentrations (BGs) are kept as close as possible to a predefined target level using variable glucose infusion rates (GIRs). In automated clamps, GIRs are calculated by algorithms implemented in the device (e.g., the Biostator). Low BG- and GIR-variability is needed for high clamp quality. We therefore tried to reduce oscillations in both BG and GIR with an improved algorithm implemented in ClampArt, a modern clamp device.

SUBJECTS AND METHODS

The Biostator algorithm was first improved by numerical simulations of glucose clamps (in silico). With the results of the simulations, we started in vitro experiments using the ClampArt device and a container with water and glucose as "test subject." After a small pilot in vivo study, a larger clinical study was performed to compare the original with the optimized algorithm.

RESULTS

With the improved algorithm, in silico, in vitro, and in vivo experiments showed reduced oscillations in both BG and GIR. In the clinical study, the coefficient of variation (CV) of BG values was lowered from 6.0% (4.6%-7.8%) [median (interquartile range)] to 4.2% (3.6%-5.0%), P < 0.0001 and the CV of GIR from 60.7% (49.6%-82.0%) to 43.5% (32.8%-57.2%), P < 0.0001. Other clamp quality parameters did not change substantially, median deviation from target slightly increased from 0.6% (0.2%-1.0%) to 1.1% (0.7%-1.5%), P = 0.0005, whereas utility did not change [97.0% (93.4%-100.0%) vs. 97.0% (94.0%-98.8%), P = 0.57].

CONCLUSIONS

With the improved algorithm, all experiments confirmed a reduction in BG- and GIR-oscillations without a major impact on other glucose clamp parameters. The optimized algorithm has been implemented in ClampArt for all future glucose clamp studies.

Duration of action of two insulin glargine products, LY2963016 insulin glargine and Lantus insulin glargine, in subjects with type 1 diabetes mellitus

AIMS

LY2963016 (LY IGlar) and Lantus (IGlar) are insulin glargine products manufactured by distinct processes, but with identical amino acid sequences. This study compared the duration of action of LY IGlar and IGlar in subjects with type 1 diabetes mellitus (T1DM).

MATERIALS AND METHODS

This was a randomized, double-blind, single-dose, two-period, crossover study. Twenty subjects underwent 42-hour euglycaemic clamps after a single subcutaneous 0.3-U/kg dose of LY IGlar or IGlar. In this study, the duration of action was defined as the time required for blood glucose levels to rise consistently above a predefined cut-off of 8.3 mmol/L (150 mg/dL) from a state of euglycaemia. Blood samples were collected to measure blood glucose for pharmacodynamic (PD) evaluations.

RESULTS

End of action was reached within 42 hours in 26 of 40 clamps (13 LY IGlar and 13 IGlar). The median duration of action for all subjects was 37.1 and 40.0 hours, and the mean duration of action (calculated using only patients who reached end of action) was 23.8 and 25.5 hours for LY IGlar and IGlar, respectively. The duration of action was demonstrated to be similar between the treatments using time-to-event analysis (log-rank test of equality p = .859). Following administration of LY IGlar and IGlar, the PD parameters of maximum glucose infusion rate (R _max ) and total glucose infusion during the clamp (G _tot ) were comparable.

CONCLUSION

LY IGlar and IGlar had similar duration of action and comparable PD parameters in subjects with T1DM.

A Comprehensive Performance Evaluation of Five Blood Glucose Systems in the Hypo-, Eu-, and Hyperglycemic Range

BACKGROUND

The objective was to evaluate the performance (in terms of accuracy, precision, and trueness) of 5 CE-certified and commercially available blood glucose (BG) systems (meters plus test strips) using an innovative clinical-experimental study design with a 3-step glucose clamp approach and frequent capillary BG measurements.

METHODS

Sixteen subjects with type 1 diabetes participated in this open label, single center trial. BG was clamped at 3 levels for 60 minutes each: 60-100-200 mg/dL. Medical staff performed regular finger pricks (up to 10 per BG level) to obtain capillary blood samples for paired BG measurements with the 5 BG systems and a laboratory method as comparison.

RESULTS

Three BG systems displayed significantly lower mean absolute relative deviations (MARD) (ACCU-Chek® Aviva Nano [5.4%], BGStar® [5.1%], iBGStar® [5.3%]) than 2 others (FreeStyle InsuLinx® [7.7%], OneTouch Verio®IQ [10.3%]). The measurement precision of all BG systems was comparable, but relative bias was also lower for the 3 systems with lower MARD (ACCU-Chek [1.3%], BGStar [-0.9%], iBGStar [1.0%]) compared with the 2 others (FreeStyle [-7.2%], OneTouch [8.9%]).

CONCLUSIONS

This 3 range glucose clamp approach enables a systematic performance evaluation of BG systems under controlled and reproducible conditions. The random error of the tested BG systems was comparable, but some showed a lower systematic error than others. These BG systems allow an accurate glucose measurement at low, normal and high BG levels.

Euglycaemic glucose clamp: what it can and cannot do, and how to do it

The hyperinsulinaemic-euglycaemic glucose clamp has always been regarded as the "gold standard" for the assessment of pharmacodynamic (PD) properties of insulin preparations; however, there has been controversy over a variety of methodogical details, such as study population, dosing time and the initial stabilization of blood glucose (BG) concentrations at the clamp target level, among clamp groups. As the impact of these details on PD results is unclear, the present review provides an overview of different methodological approaches for both the manual and the automated hyperinsulinaemic-euglycaemic glucose clamp. The advantages and limitations of several methodological details are discussed as well as the relevance of clamp results for the prediction of clinical outcomes. Overall, the best method strongly depends on the exact objective of the trial. If, for instance, duration of action is the primary objective, studies should be carried out in patients with type 1 diabetes to avoid any interference of endogenous insulin. This is less important for variables such as onset of action or early metabolic activity. The hyperinsulinaemic-euglycaemic glucose clamp has a high sensitivity to detect even minor differences between different insulin preparations. The practical relevance of potential differences, however, needs to be investigated in clinical studies. A major prerequisite for obtaining reliable glucose clamp results is the attainment of high clamp quality (i.e. keeping BG concentrations close to the clamp target throughout the experiments). Unfortunately, measures of clamp quality are often under-reported, as is the variability in PD profiles, although these might explain some unconfirmed extreme results obtained in a few clamp studies.