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Glepaglutide is a novel, long-acting, glucagon-like peptide-2 analogue in a stable aqueous formulation for subcutaneous dosing to treat patients with short bowel syndrome. This study was conducted primarily to characterise the pharmacokinetics of glepaglutide in healthy subjects.In this open-label, partially randomised, parallel-group study, healthy subjects were evenly randomised to glepaglutide 5 or 10 mg dosed subcutaneously once weekly for 6 weeks or to a single intravenous infusion of glepaglutide 1 mg. Each group comprised 15 subjects. Blood samples were drawn to determine plasma concentrations of the parent drug and its two main metabolites. Concentrations of glepaglutide were calculated as the sum of these three analytes. Citrulline was included as a pharmacodynamic biomarker. Safety was assessed throughout the study.From a comparison of pharmacokinetic parameters following subcutaneous versus intravenous dosing, it is concluded that the pharmacokinetics of glepaglutide following subcutaneous dosing are primarily determined by slow release of the two main glepaglutide metabolites from a subcutaneous depot. For subcutaneous dosing once weekly, the two main metabolites accounted for98% of the overall glepaglutide exposure at steady state, with the parent drug contributing to less than 1% of exposure. The estimated mean (95% confidence interval) effective half-life for glepaglutide 5 and 10 mg was 124 (73-185) h and 88 (31-146) h, respectively. There was an increase in the citrulline concentration for both glepaglutide subcutaneous dose levels. No safety issues were identified.Slow release of active metabolites following subcutaneous dosing leads to a significantly protracted pharmacokinetic profile for glepaglutide. These results support that once- or twice-weekly subcutaneous dosing of glepaglutide could be an efficacious therapy for intestinal rehabilitation.NCT03279302.

To quantify the impact of subject covariates on pharmacokinetics (PK) of the novel, ready-to-use glucagon analog dasiglucagon, we developed a population PK model. Dasiglucagon pharmacokinetics was dose linear in the tested dose range (0.1 to 1.0 mg) and described by a 1-compartment model with first-order absorption and elimination, including an absorption lag time and standard allometric scaling by body weight. The final model included injection site, age as covariates on bioavailability, and MDRD eGFR and sex as covariates on apparent clearance and absorption rate constant, respectively. The model also accounted for reduced drug content at end of shelf-life storage. Based on visual predictive checks the model reliably predicted observed data. The effect of covariates on dasiglucagon exposure measured by area under the concentration time curve (AUC) are shown in the figure below (predicted [95% CI]). AUCs are relative to the AUC predicted for a typical subject aged ≥ 24 years, weighing 78 kg with normal kidney function (eGFR 95 mL/min/1.73m2) and receiving a 0.6 mg dose of dasiglucagon in the abdomen. The model-predicted effects of PK covariates on dasiglucagon AUC generally fell within the observed AUC from the analysis population receiving 0.6 mg dasiglucagon (red markers, median, and 5th-95th percentile interval, n = 321) and observed across the trials to result in reliable recovery from hypoglycemia. Disclosure C. B. Knudsen: Employee; Self; Zealand Pharma A/S, Employee; Spouse/Partner; Novo Nordisk A/S, Stock/Shareholder; Self; Zealand Pharma A/S, Stock/Shareholder; Spouse/Partner; Novo Nordisk A/S. A. H. Valeur: Employee; Self; Zealand Pharma A/S. S. Maarbjerg: Employee; Self; Zealand Pharma A/S, Employee; Spouse/Partner; Zealand Pharma A/S, Stock/Shareholder; Self; Novo Nordisk A/S, Stock/Shareholder; Spouse/Partner; Zealand Pharma A/S. R. Tehranchi: Employee; Self; Zealand Pharma A/S. P. Diderichsen: Consultant; Self; Boehringer Ingelheim International GmbH, Zealand Pharma A/S, Employee; Self; Certara Netherlands bv. H. Witjes: Employee; Self; Certara.

Hypoglycaemia remains the main limiting factor in type 1 diabetes management. We developed an insulin-dependent glucagon dosing regimen for treatment of mild hypoglycaemia based on simulations. A validated glucose-insulin-glucagon model was used to describe seven virtual patients with insulin pump-treated type 1 diabetes. In each simulation, one of ten different and individualised subcutaneous insulin boluses was administered to decrease plasma glucose (PG) from 7.0 to ≤3.9 mmol/l. Insulin levels were estimated as ratio of actual to baseline serum insulin concentration (se/ba-insulin), insulin on board (IOB) or percentage of IOB to total daily insulin dose (IOB/TDD). Insulin bolus sizes were chosen to provide pre-defined insulin levels when PG reached 3.9 mmol/l, where one of 17 subcutaneous glucagon boluses was administered. Optimum glucagon bolus to treat mild hypoglycaemia at varying insulin levels was the lowest dose that in most patients caused PG peak between 5.0 and 10.0 mmol/l and sustained PG≥3.9 mmol/l for 2 hr after the bolus. PG response to glucagon declined with increasing insulin levels. The glucagon dose to optimally treat mild hypoglycaemia depended exponentially on insulin levels, regardless of how insulin was estimated. A 125-μg glucagon dose was needed to optimally treat mild hypoglycaemia when insulin levels were equal to baseline levels. In contrast, glucagon doses >500 μg were needed when se/ba-insulin >2.5, IOB >2.0U or IOB/TDD >6%. Although the proposed model-based glucagon regimen needs confirmation in clinical trials, this is the first attempt to develop an insulin-dependent glucagon dosing regimen for treatment of insulin-induced mild hypoglycaemia in patients with type 1 diabetes. This article is protected by copyright. All rights reserved.

In healthy individuals, insulin and glucagon work in a complex fashion to maintain blood glucose levels within a narrow range. This regulation is distorted in patients with diabetes. The hepatic glucose response due to an elevated glucagon level depends on the current insulin concentration and thus endogenous glucose production (EGP) can not be modelled without knowledge of the concentration of both hormones in plasma. Furthermore, literature suggests an upper limit to EGP irrespective of glucagon levels. We build a simulation model of the glucose-insulin-glucagon dynamics in man including saturation effect of EGP. Ten healthy subjects received a 1 mg subcutaneous (SC) glucagon bolus (GlucaGen®). Plasma samples were collected until 300 minutes post dose and analyzed for glucagon, insulin, and glucose concentrations. All observations were used to fit a physiological model of the glucose-insulin-glucagon dynamics using the Hovorka model with a novel multiplicative description of the effects of insulin and of glucagon on EGP. Bayesian estimation by Maximum a Posteriori using prior knowledge reported in literature was used to estimate the model parameters for each subject. Profile likelihood plots were used to investigate parameter identifiability. Unidentifiable parameters were fixed at their prior mean values. The new model enables simulations of the glucose-insulin-glucagon dynamics in humans at both low and high glucagon concentrations (180-8000 pg/mL) and physiologic insulin concentrations (1.2-81.9 mIU/L). The model can be used for simulation of glucagon bolus strategies for treatment of hypoglycemia and for in silico simulation of dual-hormone artificial pancreas algorithms.

Antiarrhythmic peptides (AAPs) are a group of compounds with antiarrhythmic properties; however, their use has been hampered by very low plasma stability. The aim of this study was to compare the in vitro and in vivo stability of our new stable AAP analog Ac-d-Tyr-d-Pro-d-Hyp-Gly-d-Ala-Gly-NH2 (ZP123) with the previously described AAP analog AAP10. Moreover, the effect of the two compounds was examined in a murine in vivo model of ouabain-induced second degree AV-block, and the effect on dispersion of action potential duration (APD dispersion) was studied during hypokalemic-ischemia in isolated perfused rabbit hearts. The in vitro t1/2 of ZP123 in rat and human plasma was about 1,700 times longer than t1/2 of AAP10. Due to rapid elimination, it was not possible to obtain an in vivo pharmacokinetic characterization of AAP10; however, calculations suggested that the clearance of ZP123 was at least 140 times slower than for AAP10. AAP10 and ZP123 produced a dose-dependent delay in onset of ouabain-induced AV-block in mice at doses of 10-11 to 10-7 mol/kg i.v. ZP123 and 10-11 to 10-6 mol/kg i.v. AAP10. Maximal efficacy of ZP123 was reached at a 10-fold lower dose (10-8 mol/kg i.v.) than with AAP10. In the isolated rabbit hearts, ZP123 and AAP10 had no effect on dispersion during control conditions. The increased APD dispersion during hypokalemic ischemia is considered a major arrhythmic substrate and only ZP123 prevented the increase in APD dispersion. In conclusion, ZP123 is a new potent AAP analog with improved stability.

An on-line capillary electrophoresis–mass spectrometry method (CE–MS) for the detection of metallothionein (MT) isoforms is described. The detected masses were usually within 1–1.5 mass units of the expected molecular weights. MT-containing samples from rabbit, sheep, and yeast (Saccharomyces cerevisiae) were subjected to CE–MS analysis. The analysis of rabbit liver MT revealed the masses of 10 proteins/peptides. Five of the detected masses corresponded well with the expected masses calculated from the amino acid sequence of previously described MT isoforms, one was suspected to be a deacetylated form of MT-2A, one was presumed to be a yet unknown isoform, and three masses were classified as non-MT compounds. From the analysis of a fetal sheep liver extract six proteins were detected of which three masses corresponded to previously described MT isoforms. Two purified MT subforms fromS. cerivisiae(encoded by theCUP1locus) were analyzed for their copper content and both forms were found to contain eight copper atoms per molecule.

Non-pharmacological in vivo models of atrial fibrillation (AF) have been developed in large animals only. We aimed to develop and characterize a new small animal non-pharmacological in vivo model of AF. AF was induced by transesophageal atrial burst pacing during 35 seconds periods of asphyxia in anesthetized male Sprague-Dawley rats. AF was reproducibly induced in 81% of the rats. The presence of AF was associated with an increased heart rate, and a decreased blood pressure. Treatment with amiodarone, D,L-sotalol, flecainide, and propranolol all reduced duration of AF, whereas verapamil treatment was associated with a marked profibrillatory effect. Increasing gap junction intracellular communication using the antiarrhythmic peptide analogue AAP10 did not affect AF duration. Basal plasma level of epinephrine and norepinephrine were increased 5- to 20-fold relative to values reported by others, but unchanged following 35 seconds of asphyxia. The results from our study demonstrate that the rat model shares several clinical key characteristics with human AF: (1) hemodynamic response to AF; (2) increased autonomic tone; (3) antiarrhythmic effects of clinically used drugs; (4) profibrillatory effect of verapamil. Relative to existing models of AF in larger animals, this model offers rapid, predictive, and inexpensive testing of antiarrhythmic/profibrillatory effects of new drugs.

Zealand Pharma has invented a glucagon analogue, ZP-GA-1, with increased stability in liquid formulation for treatment of hypoglycemia. A pharmacodynamic (PD) model is needed to compare ZP-GA-1 with marketed glucagon. We aim to develop a model of the complex glucose-insulin-glucagon dynamics based on physiology and data.