Rapid Correction of the Hypoglycemia State in Nonhuman Primates Using a Glucagon Long-Dissolving Microneedle Patch

The timely administration of glucagon is a standard clinical practice for the treatment of severe hypoglycemia. However, the process involves cumbersome steps, including the reconstitution of labile glucagon and filling of the syringe, which cause considerable delays in emergency situations. Moreover, multiple dosages are often required to prevent the recurrence of the hypoglycemic episode because of the short half-life of glucagon in plasma. Herein, we develop a glucagon-loaded long-dissolving microneedle (GLMN) patch that exhibits the properties of fast onset and sustained activity for the effective treatment of severe hypoglycemia. Three types of MN patches were fabricated with different dimensions (long, medium, and short). The longer MN patch packaged a higher dosage of glucagon and exhibited supreme mechanical strength compared to the shorter one. Additionally, the longer MN patch could insert more deeply into the skin, resulting in higher permeability of glucagon across the skin tissue and more rapid systemic absorption as compared with the shorter MN patch. The GLMN patch was observed to reverse the effects of hypoglycemia within 15 min of application in animal models (specifically, rat and rhesus monkey models) and maintained long-term glycemic control, owing to highly efficient drug permeation and the drug reservoir effect of the MN base. The current study presents a promising strategy for the rapid reversal of severe hypoglycemia that exhibits the desirable properties of easy use, high efficiency, and sustained action.

Evaluation of the cost and medical resource use outcomes associated with nasal glucagon versus injectable glucagon for treatment of severe hypoglycemia in people with diabetes in Canada: a modeling analysis

OBJECTIVES

Treatments for severe hypoglycemia aim to restore blood glucose through successful administration of rescue therapy, and choosing the most effective and cost-effective option will improve outcomes for patients and may reduce costs for healthcare payers. The present analysis aimed to compare costs and use of medical services with nasal glucagon and injectable glucagon in people with type 1 and 2 diabetes in Canada when used to treat severe hypoglycemic events when impaired consciousness precludes treatment with oral carbohydrates using an economic model, based on differences in the frequency of successful administration of the two interventions.

METHODS

A decision tree model was prepared in Microsoft Excel to project outcomes with nasal glucagon and injectable glucagon. The model structure reflected real-world decision-making and treatment outcomes, based on Canada-specific sources. The model captured the use of glucagon, emergency medical services (EMS), emergency room, inpatient stay, and follow-up care. Costs were accounted for in 2019 Canadian dollars (CAD).

RESULTS

Nasal glucagon was associated with reduced use of all medical services compared with injectable glucagon. EMS call outs were projected to be reduced by 45%, emergency room treatments by 52%, and inpatient stays by 13%. Use of nasal glucagon was associated with reduced direct, indirect, and combined costs of CAD 1,249, CAD 460, and CAD 1,709 per severe hypoglycemic event, respectively, due to avoided EMS call outs and hospital costs, resulting from a higher proportion of successful administrations.

CONCLUSIONS

When a patient with type 1 or type 2 diabetes is being treated for a severe hypoglycemic event when impaired consciousness precludes treatment with oral carbohydrate, use of nasal glucagon was projected to be dominant versus injectable glucagon in Canada reducing costs and use of medical services.

Hypoglycemia requiring paramedic assistance among adults in southwestern Ontario, Canada: a population-based retrospective cohort study

BACKGROUND

People with diabetes mellitus commonly experience hypoglycemia, but they may not necessarily present to hospital after severe hypoglycemia requiring paramedic assistance. We sought to describe the incidence and characteristics of calls for hypoglycemia requiring paramedic assistance among adults in southwestern Ontario, Canada, and to determine predictors of hospital transport.

METHODS

This population-based retrospective cohort study used data extracted from ambulance call reports (ACRs) of 8 paramedic services of the Southwest Ontario Regional Base Hospital Program from January 2008 to June 2014. We described calls in which treatment for hypoglycemia was administered, summarized the incidence of hypoglycemia calls and performed logistic regression to determine predictors of hospital transport.

RESULTS

Out of 470 467 ACRs during the study period, 9185 paramedic calls occurred in which hypoglycemia treatment was administered to an adult (mean age 60.2 yr, 56.8% male, 81.1% with documented diabetes). Refusal of hospital transport occurred in 2243 (24.4%) of calls. Documented diabetes diagnosis (adjusted odds ratio [OR] 0.82, 95% confidence interval [CI] 0.69-0.96), higher capillary blood glucose (adjusted OR 0.31, 95% CI 0.22-0.44) and overnight calls (adjusted OR 0.80, 95% CI 0.72-0.91) were associated with lower odds of hospital transport. Higher-acuity calls (adjusted OR 2.05, 95% CI 1.58-2.66) were associated with higher odds of transport. The estimated annual incidence rate of hypoglycemia requiring paramedic assistance was 108 per 10 000 people with diabetes per year.

INTERPRETATION

Hypoglycemia requiring paramedic assistance in southwestern Ontario is common, and close to 25% of calls do not result in hospital transport. Physicians managing diabetes care may be unaware of patients' hypoglycemia requiring paramedic care, suggesting a potential gap in follow-up care; we suggest that paramedics play an important role in identifying those at high recurrence risk and communicating with their care providers.

New Fast Acting Glucagon for Recovery from Hypoglycemia, a Life-Threatening Situation: Nasal Powder and Injected Stable Solutions

The goal of diabetes care is to achieve and maintain good glycemic control over time, so as to prevent or delay the development of micro- and macrovascular complications in type 1 (T1D) and type 2 diabetes (T2D). However, numerous barriers hinder the achievement of this goal, first of all the frequent episodes of hypoglycemia typical in patients treated with insulin as T1D patients, or sulphonylureas as T2D patients. The prevention strategy and treatment of hypoglycemia are important for the well-being of patients with diabetes. Hypoglycemia is strongly associated with an increased risk of cardiovascular disease in diabetic patients, due probably to the release of inflammatory markers and prothrombotic effects triggered by hypoglycemia. Treatment of hypoglycemia is traditionally based on administration of carbohydrates or of glucagon via intramuscular (IM) or subcutaneous injection (SC). The injection of traditional glucagon is cumbersome, such that glucagon is an under-utilized drug. In 1983, it was shown for the first time that intranasal (IN) glucagon increases blood glucose levels in healthy volunteers, and in 1989-1992 that IN glucagon is similar to IM glucagon in resolving hypoglycemia in normal volunteers and in patients with diabetes, both adults and children. IN glucagon was developed in 2010 and continued in 2015; in 2019 IN glucagon obtained approval in the US, Canada, and Europe for severe hypoglycemia in children and adults. In the 2010s, two ready-to-use injectable formulations, a stable non-aqueous glucagon solution and the glucagon analog dasiglucagon, were developed, showing an efficacy similar to traditional glucagon, and approved in the US in 2020 and in 2021, respectively, for severe hypoglycemia in adults and in children. Fast-acting glucagon (nasal administration and injected solutions) appears to represent a major breakthrough in the treatment of severe hypoglycemia in insulin-treated patients with diabetes, both adults and children. It is anticipated that the availability of fast-acting glucagon will expand the use of glucagon, improve overall metabolic control, and prevent hypoglycemia-related complications, in particular cardiovascular complications and cognitive impairment.

Glucagon as a Therapeutic Approach to Severe Hypoglycemia: After 100 Years, Is It Still the Antidote of Insulin?

Hypoglycemia represents a dark and tormented side of diabetes mellitus therapy. Patients treated with insulin or drug inducing hypoglycemia, consider hypoglycemia as a harmful element, which leads to their resistance and lack of acceptance of the pathology and relative therapies. Severe hypoglycemia, in itself, is a risk for patients and relatives. The possibility to have novel strategies and scientific knowledge concerning hypoglycemia could represent an enormous benefit. Novel available glucagon formulations, even now, allow clinicians to deal with hypoglycemia differently with respect to past years. Novel scientific evidence leads to advances concerning physiopathological mechanisms that regulated glycemic homeostasis. In this review, we will try to show some of the important aspects of this field.

Dasiglucagon, a next-generation ready-to-use glucagon analog, for treatment of severe hypoglycemia in children and adolescents with type 1 diabetes: Results of a phase 3, randomized controlled trial

BACKGROUND

Dasiglucagon, a next-generation, ready-to-use aqueous glucagon analog formulation, has been developed to treat severe hypoglycemia in individuals with diabetes.

OBJECTIVE

The aim of this trial was to evaluate the safety and efficacy of dasiglucagon in pediatric individuals with type 1 diabetes (T1DM). Participants were children and adolescents (6-17 years) with T1DM.

METHODS

In this randomized double-blind trial, 42 participants were randomly allocated (2:1:1) to a single subcutaneous (SC) injection of dasiglucagon (0.6 mg), placebo, or reconstituted glucagon (GlucaGen; dosed per label) during insulin-induced hypoglycemia. The primary endpoint was time to plasma glucose (PG) recovery (first PG increase ≥20 mg/dL after treatment initiation without rescue intravenous glucose). The primary comparison was dasiglucagon vs. placebo; glucagon acted as a reference.

RESULTS

The median time (95% confidence interval) to PG recovery following SC injection was 10 min (8-12) for dasiglucagon vs. 30 min (20 to -) for placebo (P < .001); the median time for glucagon was 10 min (8-12), which did not include the time taken to reconstitute the lyophilized powder. PG recovery was achieved in all participants in the dasiglucagon and glucagon groups within 20 min of dosing compared to 2 out of 11 patients (18%) with placebo. The most frequent adverse events were nausea and vomiting, as expected with glucagon treatment.

CONCLUSIONS

Consistent with adult phase 3 trials, dasiglucagon rapidly and effectively restored PG levels following insulin-induced hypoglycemia in children and adolescents with T1DM, with an overall safety profile similar to glucagon.

Glucagon delivery - An overview of current and future devices

Glucagon is crucial in the treatment of Type 1 diabetes mellitus due to the prevalence of hypoglycemia in patients with this disorder. Hypoglycemia can be life-threatening, leading to loss of consciousness, and requiring emergency glucagon to reverse the effects. Emergency kits are difficult to use, requiring reconstitution of glucagon, which itself is not stable for lengthy periods. Approaches have aimed to improve stability which has allowed for use in pens or pumps. Glucagon can now also be delivered intranasally. This review discusses the history of glucagon, its current delivery methods as well as some modern approaches being introduced.

Prolonged Glucagon Infusion Does Not Affect Energy Expenditure in Individuals with Overweight/Obesity: A Randomized Trial

OBJECTIVE

The aim of this study was to determine the effects of prolonged (72 hours) glucagon administration at a low dose (LD) (12.5 ng/kg/min) and high dose (HD) (25 ng/kg/min) on energy expenditure (EE) in healthy individuals with overweight or obesity.

METHODS

Thirty-one healthy participants with overweight or obesity (BMI of 27-45 kg/m² , 26-55 years old, 23 females) were randomized into LD, HD, or placebo groups and underwent 72-hour intravenous infusion of glucagon. Whole-room calorimetry was used to assess EE and substrate use during five overnight stays (2 days at baseline, 3 days of infusion) and during two 24-hour stays (baseline vs. day 3). Blood was sampled at regular intervals throughout the inpatient stay and analyzed for glucagon and biomarkers of metabolism.

RESULTS

HD infusion elevated plasma glucagon levels compared with the placebo and LD infusion (P < 0.001). Sleeping, basal, and 24-hour EE was not significantly different among groups at any time point. Those receiving HD had significantly higher basal fat oxidation (Fat Ox) at days 2 and 3 than those receiving the placebo (P < 0.05); however, no differences in 24-hour Fat Ox were observed among groups (baseline vs. day 3).

CONCLUSIONS

An HD plasma glucagon infusion over 72 hours does not increase any aspects of EE in healthy individuals with overweight or obesity.

Dasiglucagon: First Approval

Dasiglucagon (Zegalogue^®) is an antihypoglycaemic agent being developed by Zealand Pharma for the treatment of hypoglycaemia, type 1 diabetes mellitus (T1DM) management and congenital hyperinsulinism. In March 2021, dasiglucagon received its first approval in the USA for the treatment of severe hypoglycaemia in paediatric and adult patients with diabetes aged 6 years and above. Dasiglucagon, a glucagon analogue, is available as a single-dose autoinjector or prefilled syringe for subcutaneous injection. This article summarizes the milestones in the development of dasiglucagon leading to this first approval for hypoglycaemia.

Glucose effectiveness: Lessons from studies on insulin-independent glucose clearance in mice

Besides insulin-mediated transport of glucose into the cells, an important role is also played by the non-insulin-mediated transport. This latter process is called glucose effectiveness (acronym SG ), which is estimated by modeling of glucose and insulin data after an intravenous glucose administration, and accounts for ≈70% of glucose disposal. This review summarizes studies on SG , mainly in humans and rodents with focus on results achieved in model experiments in mice. In humans, SG is reduced in type 2 diabetes, in obesity, in liver cirrhosis and in some elderly populations. In model experiments in mice, SG is independent from glucose levels, but increases when insulin secretion is stimulated, such as after administration of the incretin hormones, glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. SG is reduced in insulin resistance induced by high-fat feeding and by exogenous administration of glucagon. Glucose-dependent (insulin-independent) glucose disposal is therefore important for glucose elimination, and it is also well regulated. It might be of pathophysiological relevance for the development of type 2 diabetes, in particular during insulin resistance, and might also be a target for glucose-reducing therapy. Measuring SG is essentially important when carrying out metabolic studies to understand glucose homeostasis.

Glucagon stimulation test to assess growth hormone status in Prader-Willi syndrome

PURPOSE

Growth hormone deficiency (GHD) must be confirmed before starting treatment in adults with Prader-Willi syndrome (PWS). Most studies use the growth-hormone-releasing hormone plus arginine (GHRH-arginine) test. No data are available on the glucagon stimulation test (GST) in PWS. We compared the utility of fixed-dose (1 mg) GST versus GHRH-arginine test in diagnosing GHD.

METHODS

Adults and late adolescents with PWS underwent both tests on separate days. In the GHRH-arginine test, GHD was defined according to body mass index. In the GST, two cutoffs were analyzed: peak GH concentration < 3 ng/mL and < 1 ng/mL. For analyses, patients were divided into two groups according to body weight (≤ 90 kg and > 90 kg).

RESULTS

We analyzed 34 patients: 22 weighing ≤ 90 kg and 12 weighing > 90 kg. In patients weighing ≤ 90 kg, the two tests were concordant in 16 (72.72%) patients (k = 0.476, p = 0.009 with GST cutoff < 3 ng/mL, and k = 0.450, p = 0.035 with GST cutoff < 1 ng/mL). In patients weighing > 90 kg, the two tests were not concordant with GST cutoff < 3 ng/mL, but were concordant in 11 (91.6%) patients (k = 0.833, p = 0.003) with GST cutoff < 1 ng/mL. GH peaks on the two tests correlated (r = 0.725, p = 0.008).

CONCLUSION

Fixed-dose (1 mg) GST using a peak GH cutoff of < 3 ng/mL or < 1 ng/mL promises to be useful for screening for GHD in adults and late adolescents with PWS. However, in those weighing > 90 kg, the < 1 ng/mL cutoff seems better. Larger studies are necessary to establish definitive glucagon doses and cutoffs, especially in extremely obese patients.

Paracrine regulation of somatostatin secretion by insulin and glucagon in mouse pancreatic islets

AIMS/HYPOTHESIS

The endocrine pancreas comprises the islets of Langerhans, primarily consisting of beta cells, alpha cells and delta cells responsible for secretion of insulin, glucagon and somatostatin, respectively. A certain level of intra-islet communication is thought to exist, where the individual hormones may reach the other islet cells and regulate their secretion. Glucagon has been demonstrated to importantly regulate insulin secretion, while somatostatin powerfully inhibits both insulin and glucagon secretion. In this study we investigated how secretion of somatostatin is regulated by paracrine signalling from glucagon and insulin.

METHODS

Somatostatin secretion was measured from perfused mouse pancreases isolated from wild-type as well as diphtheria toxin-induced alpha cell knockdown, and global glucagon receptor knockout (Gcgr^-/-) mice. We studied the effects of varying glucose concentrations together with infusions of arginine, glucagon, insulin and somatostatin, as well as infusions of antagonists of insulin, somatostatin and glucagon-like peptide 1 (GLP-1) receptors.

RESULTS

A tonic inhibitory role of somatostatin was demonstrated with infusion of somatostatin receptor antagonists, which significantly increased glucagon secretion at low and high glucose, whereas insulin secretion was only increased at high glucose levels. Infusion of glucagon dose-dependently increased somatostatin secretion approximately twofold in control mice. Exogenous glucagon had no effect on somatostatin secretion in Gcgr^-/- mice, and a reduced effect when combined with the GLP-1 receptor antagonist exendin 9-39. Diphtheria toxin-induced knockdown of glucagon producing cells led to reduced somatostatin secretion in response to 12 mmol/l glucose and arginine infusions. In Gcgr^-/- mice (where glucagon levels are dramatically increased) overall somatostatin secretion was increased. However, infusion of exendin 9-39 in Gcgr^-/- mice completely abolished somatostatin secretion in response to glucose and arginine. Neither insulin nor an insulin receptor antagonist (S961) had any effect on somatostatin secretion.

CONCLUSIONS/INTERPRETATION

Our findings demonstrate that somatostatin and glucagon secretion are linked in a reciprocal feedback cycle with somatostatin inhibiting glucagon secretion at low and high glucose levels, and glucagon stimulating somatostatin secretion via the glucagon and GLP-1 receptors. Graphical abstract.

Glucose transporter 2 in common carp (Cyprinus carpio L.): molecular cloning, tissue expression, and the responsiveness to glucose, insulin, and glucagon

Glucose transporter 2 (glut2) has been studied in mammals, aves, and several fish, while the comparative studies of glut2 in common carp are still lacking. In this study, glut2 was firstly isolated and characterized from the liver of common carp. The full-length cDNA of glut2 was 2351 bp with an open reading frame (ORF) of 1512 bp, encoding 503 amino acids. Alignment of glut2 amino acid sequences from different species revealed that common carp glut2 showed higher sequence identity with teleosts, and lower homology with mammals and amphibians. Tissue distribution demonstrated that glut2 mRNA level was mainly expressed in liver, foregut, and midgut. To investigate the actions of glut2 on glucose metabolism, the level of glut2 mRNA was detected after intraperitoneal injection of glucose, human insulin and glucagon (100 ng/g), respectively. Following glucose administration, glut2 gene expression was significantly upregulated at 3 h in the foregut. However, no change was found in hepatic glut2 mRNA level, indicating that glut2 may have a role in intestinal glucose uptake rather than in the liver. Following insulin treatment, the expression of glut2 was markedly downregulated at 3 h and 6 h in the liver, and at 3 h in the foregut, respectively. Furthermore, glut2 mRNA expression was unaffected by glucagon injection in the liver and foregut. These results suggested that the expression of glut2 regulated by pancreatic hormones was different. Taken together, our studies firstly revealed the structure of the glut2 gene and its potential functions in glucose metabolism of common carp.

Molecular identification of grass carp igfbp2 and the effect of glucose, insulin, and glucagon on igfbp2 mRNA expression

The GH (growth hormone)/IGFs (insulin-like growth factors) system has an important function in the regulation of growth. In this system, IGFBPs play a crucial regulatory role in IGF functions. As a member of the IGFBP family, IGFBP2 can bind to IGF and regulate IGF functions to regulate development and growth. In addition, IGFBP2 shows key regulatory functions in cell proliferation and metabolism. In this study, the igfbp2 gene was cloned from grass carp (Ctenopharyngodon idellus) liver. The ORF of grass carp igfbp2 is 834 bp long and encodes 277 amino acids. The tissue distribution results showed that igfbp2 is expressed in multiple tissues in grass carp and has a high expression level in the liver. In the OGTT, igfbp2 expression was significantly decreased in the liver and brain after 6 h of treatment with glucose. In vitro, igfbp2 expression in grass carp's primary hepatocytes was significantly suppressed by insulin after treatment for 6 and 12 h. Moreover, igfbp2 expression was markedly increased in a dose-dependent manner with glucagon incubation in grass carp's primary hepatocytes. To the best of our knowledge, this is the first report about Igfbp2 in grass carp. These results will provide a basis for the in-depth study of grass carp Igfbp2.

A ready-to-use liquid glucagon for treatment of severe hypoglycemia demonstrates reduced healthcare payer costs in a budget impact model

Research aim: To model the annual value of a novel ready-to-use, room-temperature stable liquid glucagon rescue pen and prefilled syringe (GRP, G-PFS; Xeris Pharmaceuticals, Inc.) for treatment of severe hypoglycemia events (SHE) versus current lyophilized powder glucagon emergency kits (GEK). GRP is a prefilled auto-injector designed to promptly administer concentrated liquid glucagon in a simple two-step process. G-PFS is a stable liquid formulation of glucagon in a prefilled syringe. In simulated emergencies, GRP and G-PFS demonstrated high functional efficacy, where 99% of users successfully administered a full-dose of drug. Studies with currently available injectable GEK suggest very low success rates (6-31%). The high functional efficacy of GRP and G-PFS significantly reduces user errors and may reduce utilization across emergency medical services (EMS), emergency departments (ED), and inpatient and outpatient costs for SHE.Methods: To estimate the economic impact of GRP and G-PFS, we developed a one-year budget impact model from a US commercial health plan perspective. Cost offsets from successful glucagon administration incorporated EMS, ED, inpatient, and outpatient utilization. Diabetes prevalence and event probabilities were estimated from publicly-available sources and clinical expert opinion. Costs (US$) were obtained from the 2018 Medicare Fee Schedules and adjusted to represent commercial payer costs.Results: GRP and G-PFS led to fewer EMS, ED, inpatient, and outpatient costs compared to GEK and no kit, resulting in total per-patient SHE costs of $2,564, $3,606, and $3,849, respectively. Costs for 1 million covered lives were 8.2 million following the introduction of GRP and G-PFS compared to almost 9 million before GRP and G-PFS.Limitations: The model is limited by reliance on assumptions based on expert opinion for key variables, primarily the probability of: (1) ambulance calls, (2) ambulance transport to the ED, and (3) non-ambulance transport to the ED.Conclusions: A budget impact model suggests GRP and G-PFS can lead to significant annual cost savings for US commercial payers.

Intranasal versus injectable glucagon for hypoglycemia in type 1 diabetes: systematic review and meta-analysis

AIMS

Glucagon is used to resolve severe hypoglycemia in unconscious patients with diabetes, requiring third-party assistance. A few studies have shown that intranasal (IN) glucagon causes resolution of hypoglycemia in insulin-treated patients with type 1 (T1DM) diabetes. This systematic review and meta-analysis updates the comparison of the effectiveness of IN glucagon with injected intramuscular/subcutaneous (IM/SC) glucagon in treatment of hypoglycemia in T1DM.

METHODS

Controlled randomized studies were considered; eight studies, published in English, were included in a meta-analysis (random-effects model). Intervention effect (resolution of hypoglycemia) was expressed as odds ratio (OR), with 95% confidence intervals. Meta-regression was employed to correlate the effect with size of studies, age of patients, basal blood glucose levels.

RESULTS

In a total of 467 treatments in 269 patients with IN and IM/SC glucagon, the OR IN versus IM/SC was 0.61 (CI 0.13-2.82); since four of eight studies showed 100% effectiveness, a simulation was made with 1 failure for each treatment; in this simulation analysis, the OR was 0.80 (95% CI 0.28-2.32). Heterogeneity was low and not statistically significant. Publication bias was absent, and quality of papers was high. At meta-regression, no correlation was found between the effect and number of patients in each study, age of patients, basal blood glucose levels. No study formally compared IN versus IM/SC in unconscious patients.

CONCLUSIONS

This meta-analysis indicates that in conscious T1DM patients IN glucagon and IM/SC glucagon are equally effective in resolution of hypoglycemia.

Acute Effects of Glucagon on Reproductive Hormone Secretion in Healthy Men

CONTEXT

Glucagon increases energy expenditure; consequently, glucagon receptor agonists are in development for the treatment of obesity. Obesity negatively affects the reproductive axis, and hypogonadism itself can exacerbate weight gain. Therefore, knowledge of the effects of glucagon receptor agonism on reproductive hormones is important for developing therapeutics for obesity; but reports in the literature about the effects of glucagon receptor agonism on the reproductive axis are conflicting.

OBJECTIVE

The objective of this work is to investigate the effect of glucagon administration on reproductive hormone secretion in healthy young men.

DESIGN

A single-blinded, randomized, placebo-controlled crossover study was conducted.

SETTING

The setting of this study was the Clinical Research Facility, Imperial College Healthcare NHS Trust.

PARTICIPANTS

Eighteen healthy eugonadal men (mean ± SEM: age 25.1 ± 1.0 years; body mass index 22.5 ± 0.4 kg/m2; testosterone 21.2 ± 1.2 nmol/L) participated in this study.

INTERVENTION

An 8-hour intravenous infusion of 2 pmol/kg/min glucagon or rate-matched vehicle infusion was administered.

MAIN OUTCOME MEASURES

Luteinizing hormone (LH) pulsatility; LH, follicle-stimulating hormone (FSH), and testosterone levels were measured.

RESULTS

Although glucagon administration induced metabolic effects (insulin area under the curve: vehicle 1065 ± 292 min.µU/mL vs glucagon 2098 ± 358 min.µU/mL, P < .001), it did not affect LH pulsatility (number of LH pulses/500 min: vehicle 4.7 ± 0.4, glucagon 4.2 ± 0.4, P = .22). Additionally, there were no significant differences in circulating LH, FSH, or testosterone levels during glucagon administration compared with vehicle administration.

CONCLUSIONS

Acute administration of a metabolically active dose of glucagon does not alter reproductive hormone secretion in healthy men. These data are important for the continued development of glucagon-based treatments for obesity.

Conservative management of oesophageal soft food bolus impaction

BACKGROUND

Impaction of a soft food bolus in the oesophagus causes dysphagia and regurgitation. If the bolus does not pass spontaneously, then the patient is at risk of aspiration, dehydration, perforation, and death. Definitive management is with endoscopic intervention, recommended within 24 hours. Prior to endoscopy, many patients undergo a period of observation, awaiting spontaneous disimpaction, or may undergo enteral or parenteral treatments to attempt to dislodge the bolus. There is little consensus as to which of these conservative strategies is safe and effective to be used in this initial period, before resorting to definitive endoscopic management for persistent impaction.

OBJECTIVES

To evaluate the efficacy of non-endoscopic conservative treatments in the management of soft food boluses impacted within the oesophagus.

SEARCH METHODS

We searched the following databases, using relevant search terms: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and CINAHL. The date of the search was 18 August 2019. We screened the reference lists of relevant studies and reviews on the topic to identify any additional studies.

SELECTION CRITERIA

We included randomised controlled trials of the management of acute oesophageal soft food bolus impaction, in adults and children, reporting the incidence of disimpaction (confirmed radiologically or clinically by return to oral diet) without the need for endoscopic intervention. We did not include studies focusing on sharp or solid object impaction.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures recommended by Cochrane.

MAIN RESULTS

We identified 890 unique records through the electronic searches. We excluded 809 clearly irrelevant records and retrieved 81 records for further assessment. We subsequently included one randomised controlled trial that met the eligibility criteria, which was conducted in four Swedish centres and randomised 43 participants to receive either intravenous diazepam followed by glucagon, or intravenous placebos. The effect of the active substances compared with placebo on rates of disimpaction without intervention is uncertain, as the numbers from this single study were small, and the rates were similar (38% versus 32%; risk ratio 1.19, 95% confidence interval 0.51 to 2.75, P = 0.69). The certainty of the evidence using GRADE for this outcome is low. Data on adverse events were lacking.

AUTHORS' CONCLUSIONS

There is currently inadequate data to recommend the use of any enteral or parenteral treatments in the management of acute oesophageal soft food bolus impaction. There is also inadequate data regarding potential adverse events from the use of these treatments, or from potential delays in definitive endoscopic management. Caution should be exercised when using any conservative management strategies in these patients.

Anti-inflammatory and atheroprotective properties of glucagon

Although glucagon has been shown to exert pleiotropic actions in various types of cells and organs through the interaction with its receptor, its pathophysiological role in atherosclerotic cardiovascular disease remains unclear. Here, we examined whether and how glucagon could attenuate the progression of atherosclerotic plaques in apolipoprotein E-deficient mice (ApoE^-/-), an animal model of atherosclerosis. Glucagon (138 or 413 nmol/kg/day) or vehicle was infused to mice at 16 weeks of age. After 4-week treatment, vascular samples were collected for histological and RT-PCR analyses. Human monocytic THP-1 cells were pre-incubated with or without a glucagon receptor antagonist L-168049, and then treated with or without glucagon for 7 h. Gene and protein expressions were determined by RT-PCR and western blot analyses, respectively. High-dose glucagon infusion significantly decreased aortic plaque area and volume in ApoE^-/- mice, both of which were inversely correlated with plasma glucagon levels. Glucagon infusion also reduced the ratio of pro-inflammatory interleukin-1β to anti-inflammatory interleukin-10 gene expression in aortae. Glucagon receptor was expressed in THP-1 cells, and 1 nM glucagon decreased the ratio of interleukin-1β to interleukin-10 gene expression, which was significantly prevented by L-168049. Our present findings suggest that glucagon could exert atheroprotection partly via its anti-inflammatory property.

A Randomized, Placebo-Controlled Double-Blind Trial of a Closed-Loop Glucagon System for Postbariatric Hypoglycemia

BACKGROUND

Postbariatric hypoglycemia (PBH) can threaten safety and reduce quality of life. Current therapies are incompletely effective.

METHODS

Patients with PBH were enrolled in a double-blind, placebo-controlled, crossover trial to evaluate a closed-loop glucose-responsive automated glucagon delivery system designed to reduce severe hypoglycemia. A hypoglycemia detection and mitigation algorithm was embedded in the artificial pancreas system connected to a continuous glucose monitor (CGM, Dexcom) driving a patch infusion pump (Insulet) filled with liquid investigational glucagon (Xeris) or placebo (vehicle). Sensor/plasma glucose responses to mixed meal were assessed during 2 study visits. The system delivered up to 2 doses of study drug (300/150 μg glucagon or equal-volume vehicle) if triggered by the algorithm. Rescue dextrose was given for plasma glucose <55 mg/dL or neuroglycopenia.

RESULTS

Twelve participants (11 females/1 male, age 52 ± 2, 8 ± 1 years postsurgery, mean ± SEM) completed all visits. Predictive hypoglycemia alerts prompted automated drug delivery postmeal, when sensor glucose was 114 ± 7 vs 121 ± 5 mg/dL (P = .39). Seven participants required rescue glucose after vehicle but not glucagon (P = .008). Five participants had severe hypoglycemia (<55 mg/dL) after vehicle but not glucagon (P = .03). Nadir plasma glucose was higher with glucagon vs vehicle (67 ± 3 vs 59 ± 2 mg/dL, P = .004). Plasma glucagon rose after glucagon delivery (1231 ± 187 vs 16 ± 1 pg/mL at 30 minutes, P = .001). No rebound hyperglycemia occurred. Transient infusion site discomfort was reported with both glucagon (n = 11/12) and vehicle (n = 10/12). No other adverse events were observed.

CONCLUSION

A CGM-guided closed-loop rescue system can detect imminent hypoglycemia and deliver glucagon, reducing severe hypoglycemia in PBH.

CLINICAL TRIALS REGISTRATION

NCT03255629.

Role of Glucagon in Automated Insulin Delivery

Treatment of type 1 diabetes with exogenous insulin often results in unpredictable daily glucose variability and hypoglycemia, which can be dangerous. Automated insulin delivery systems can improve glucose control while reducing burden for people with diabetes. One approach to improve treatment outcomes is to incorporate the counter-regulatory hormone glucagon into the automated delivery system to help prevent the hypoglycemia that can be induced by the slow pharmacodynamics of insulin action. This article explores the advantages and disadvantages of incorporating glucagon into dual-hormone automated hormone delivery systems.

Mini-doses of glucagon to prevent hypoglycemia in children with type 1 diabetes refusing food: a case series

AIMS

Hypoglycemia in small children with type 1 diabetes is difficult to manage if nausea, vomit or food refusal occurs. If oral carbohydrate cannot be used, there is a hypothetical risk of severe hypoglycemia. The present article describes the effect on glucose of small doses of subcutaneous glucagon to revert hypoglycemia and prevent severe events in small children with type 1 diabetes using a continuous glucose monitoring.

METHODS

We analyzed 4 episodes of impending or mild hypoglycemia in 3 children with type 1 diabetes who refused to eat carbohydrates. Using a standard U-100 insulin syringe, children received one "unit" (10 μg) of glucagon subcutaneously for every year of age up to 15 units (150 μg). If the blood glucose did not increase within 30 min, the initial dosage was repeated at that time. Instructions were given by phone from the physician. At the following visit data from continuous glucose monitoring devices, insulin pump and glucometer were downloaded and reviewed retrospectively from the physician.

RESULTS

Blood glucose from continuous glucose monitoring after one and 2 h was 127 ± 80 mg/dl and 165 ± 78 mg/dl, respectively. After a glucagon injection, there was a single recurrence of hypoglycemia, requiring another shot. The glucagon was well tolerated, except for nausea, present before the injection. None of the children were taken to our hospital because of concerns for hypoglycemia.

CONCLUSION

Mini-doses of glucagon given subcutaneously were effective and safe in preventing frank or impending hypoglycemia in type 1 diabetes children refusing food.

Glucose Sensor Accuracy After Subcutaneous Glucagon Injections Near to Sensor Site

Background: Integrated hormone delivery and glucose sensing is warranted, but system performance could be challenged by glucose sensor susceptibility to pharmacological interferences. The aim of this study was to compare sensor accuracy (Medtronic Enlite 2^®) after subcutaneous (s.c.) administration of low-dose glucagon near to versus remote from sensor site. Methods: Twelve adults with insulin-pump-treated type 1 diabetes wore two continuous glucose monitors (CGM_glucagon and CGM_control) placed on each side of the abdomen before, during, and after two overnight 14-h in-clinic visits. During each visit, a s.c. 100 μg glucagon injection was administered 2 cm next to the CGM_glucagon followed by another injection of 100 μg glucagon 2 h later at the same site. CGM performance was evaluated using 4-h in-clinic Yellow Spring Instrument (YSI) measurements and 3-day self-monitoring of blood glucose (SMBG) in free-living conditions. Results: Using YSI as comparator, no difference in the median absolute relative difference (MARD) for CGM_glucagon (15.7%) and CGM_control (13.4%) was found (P = 0.195). Similarly, no difference in MARD was found between CGM_glucagon (11.0%) and CGM_control (6.2%) using SMBG as comparator (P = 0.148). Values in zone A + B of Clarke error grid analysis did not differ between CGM_glucagon and CGM_control using YSI (93.9% vs. 91.1%, P = 0.250) and SMBG (97.3% vs. 95.0%, P = 0.375) as reference measurement. The precision absolute relative deviation between sensors was 13.7%. Conclusions: Sensor accuracy was not significantly affected by administration of s.c. glucagon near to sensor site.

Efficacy of Dose-Titrated Glucagon Infusions in the Management of Congenital Hyperinsulinism: A Case Series

Background: Congenital hyperinsulinism (CHI), a rare disease of excessive and dysregulated insulin secretion, can lead to prolonged and severe hypoglycemia. Dextrose infusions are a mainstay of therapy to restore normal glycemia, but can be associated with volume overload, especially in infants. By releasing intrahepatic glucose stores, glucagon infusions can reduce dependency on dextrose infusions. Recent studies have reported positive outcomes with glucagon infusions in patients with CHI; however, to date, there are no reports describing the clinical utility of titrated doses of infused glucagon to achieve glycemic stability. Objective: To assess the potential clinical utility of dose-titrated glucagon infusions in stabilizing glycemic status in pediatric patients with CHI, who were managed by medical and/or surgical approaches. Methods: Patients with CHI (N = 33), with or without mutations in the ATP-sensitive K⁺ channel genes, ABCC8, and KCNJ11 requiring glucagon by dose titration in addition to intravenous dextrose and medical therapy with diazoxide/octreotide to achieve glycemic stability were recruited. Following glucagon titration and a 24-h glucose stable period, glucose infusion rate (GIR) was reduced over a 24-h period. Achievement of glycemic stability and decrease in GIR were considered end points of the study. Results: All patients achieved glycemic stability with glucagon infusion, demonstrating clinical benefit. GIR reduced from 15.6 (4.5) to 13.4 (4.6) mg/kg/min mean (SD) (p = 0.00019 for difference; n = 32; paired t-test) over 24 h. By univariate analysis, no individual baseline characteristic was associated with changes in the GIR. However, by baseline-adjusted modeling, mutational status of the patient (p = 0.011) was inversely associated with a reduction in GIR. Adverse events were infrequent with diarrhea possibly attributed to glucagon treatment in 1 patient. With long-term treatment following GIR reduction, necrolytic migratory erythema was observed in another patient. Conclusion: These data suggest that dose-titrated glucagon infusion therapy aids hypoglycemia prevention and reduction in GIR in the clinical management of patients with CHI.

Cortisol Levels in Glucagon Stimulation Test in Children Assessed for Short Stature: Clinical and Laboratorial Correlations

To assess total cortisol levels in children being evaluating for short stature with normal cortisol reserve and to correlate this response to clinical and laboratory data. Children assessed with glucagon test in our department were recruited in this study retrospectively. Inclusion criteria were: i) age>1 year, ii) absence of chronic illness or medication interfering with ACTH-cortisol axis, iii) GH stimulation levels>3ng/mL at least in one provocation test (glucagon or clonidine), iv) absence of multiple pituitary growth hormone deficiencies, v) normal short Synacthen test in cases of low cortisol response in glucagon test.Two hundred and thirty-seven subjects (160 males, 67.5%) with a mean age of 9.02±3.19 years, were finally included in the analysis. Cortisol peak levels but not cortisol AUC were significantly increased in females compared to males (26.83±7.31 μg/dl vs. 24.04±7.20 μg/dl). When linear correlations were studied, both cortisol peak levels and cortisol AUC were linearly but inversely correlated to age (r=-0.234, p<0.001 and r=-0.315, p<0.001, respectively). Finally, cortisol AUC was inversely correlated to weight Z-scores (r=-0.160, p=0.014). When our analysis was limited only to subjects with intact GH response (GH peak> 7 ng/mL), age was still inversely correlated to cortisol AUC (r=-0.312, p<0.001), and cortisol AUC was linearly correlated to GH AUC assessed with clonidine test (r=0.223, p=0.013). Girls, younger and thinner children exhibit higher cortisol response to glucagon test.

Parallel Control of an Artificial Pancreas with Coordinated Insulin, Glucagon, and Rescue Carbohydrate Control Actions

BACKGROUND

An artificial pancreas with insulin and glucagon delivery has the potential to reduce the risk of hypo- and hyperglycemia in people with type 1 diabetes. However, a maximum dose of glucagon of 1 mg/d is recommended, potentially still requiring rescue carbohydrates in some situations. This work presents a parallel control structure with intrinsic insulin, glucagon, and rescue carbohydrates coordination to overcome glucagon limitations when needed.

METHODS

The coordinated controller that combines insulin, glucagon, and rescue carbohydrate suggestions (DH-CC-CHO) was compared with the insulin and glucagon delivery coordinated controller (DH-CC). The impact of carbohydrate quantization for practical delivery was also assessed. An in silico study using the UVA-Padova simulator, extended to include exercise and various sources of variability, was performed.

RESULTS

DH-CC and DH-CC-CHO performed similarly with regard to mean glucose (126.25 [123.43; 130.73] vs 127.92 [123.99; 132.97] mg/dL, P = .088), time in range (93.04 [90.00; 95.92] vs 92.91 [90.05; 95.75]%, P = .508), time above 180 mg/dL (4.94 [2.72; 7.53] vs 4.99 [2.93; 7.24]%, P = .966), time below 70 mg/dL (0.61 [0.09; 1.75] vs 0.96 [0.23; 2.17]%, P = .1364), insulin delivery (43.50 [38.68; 51.75] vs 42.86 [38.58; 51.36] U/d, P = .383), and glucagon delivery (0.75 [0.40; 1.83] vs 0.76 [0.43; 0.99] mg/d, P = .407). Time below 54 mg/dL was different (0.00 [0.00; 0.05] vs 0.00 [0.00; 0.16]%, P = .036), although non-clinically significant. This was due to the carbs quantization effect in a specific patient, as no statistical difference was found when carbs were not quantized (0.00 [0.00; 0.05] vs 0.00 [0.00; 0.00]%, P = .265).

CONCLUSIONS

The new strategy of automatic rescue carbohydrates suggestion in coordination with insulin and glucagon delivery to overcome constraints on daily glucagon delivery was successfully evaluated in an in silico proof of concept.

Increment of plasma glucose by exogenous glucagon is associated with present and future renal function in type 2 diabetes:a retrospective study from glucagon stimulation test

BACKGROUND

Glucagon stimulation test (GST) is often employed to assess the insulin reserve of the pancreatic beta cells in diabetic subjects. The clinical significance of the increment of plasma glucose (Δglucose) by exogenous glucagon during GST has not been elucidated. We investigated the relationship between Δglucose and clinical parameters including the liver and renal function in type 2 diabetic subjects, since we hypothesized that Δglucose is associated with the liver and renal function reflecting the capacity for gluconeogenesis in the organs.

METHODS

A total of 209 subjects with type 2 diabetes who underwent GST during admission were included in this cross-sectional study. We defined the difference between plasma glucose at fasting and 6 min after intravenous injection of 1 mg glucagon as Δglucose. We assessed correlations between Δglucose and clinical parameters such as diabetic duration, BMI, HbA1c, beta cell function, serum free fatty acids (FFA) which is known to stimulate gluconeogenesis, liver function, the indices of liver function, renal function, and urinary albumin excretion (UAE).

RESULTS

In correlation analysis, Δglucose positively correlated to FFA and estimated glomerular filtration rate (eGFR), but inversely to serum creatinine and cystatin C, although Δglucose showed no correlation with both liver function and the indices of residual liver function. Multiple regression analysis revealed that Δglucose was an independent determinant for the eGFR after 1 year, equally BMI, HbA1c, serum lipids, and UAE, which are known as the predictors for the development of chronic kidney disease.

CONCLUSION

Our results suggest that Δglucose during GST might be related to gluconeogenesis in the kidney and could be the determinant of future renal function in type 2 diabetes.

Novel Preparations of Glucagon for the Prevention and Treatment of Hypoglycemia

PURPOSE OF REVIEW

New more stable formulations of glucagon have recently become available, and these provide an opportunity to expand the clinical roles of this hormone in the prevention and management of insulin-induced hypoglycemia. This is applicable in type 1 diabetes, hyperinsulinism, and alimentary hypoglycemia. The aim of this review is to describe these new formulations of glucagon and to provide an overview of current and future therapeutic opportunities that these may provide.

RECENT FINDINGS

Four main categories of glucagon formulation have been studied: intranasal glucagon, biochaperone glucagon, dasiglucagon, and non-aqueous soluble glucagon. All four have demonstrated similar glycemic responses to standard glucagon formulations when administered during hypoglycemia. In addition, potential roles of these formulations in the management of congenital hyperinsulinism, alimentary hypoglycemia, and exercise-induced hypoglycemia in type 1 diabetes have been described. As our experience with newer glucagon preparations increases, the role of glucagon is likely to expand beyond the emergency use that this medication has been limited to in the past. The innovations described in this review likely represent early examples of a pending large repertoire of indications for stable glucagon.

Nasal Glucagon Versus Injectable Glucagon for Severe Hypoglycemia: A Cost-Offset and Budget Impact Analysis

BACKGROUND

Severe hypoglycemic events (SHEs) in patients with diabetes are associated with substantial health care costs in the United States (US). Injectable glucagon (IG) is currently available for treatment of severe hypoglycemia but is associated with frequent handling errors. Nasal glucagon (NG) is a novel, easier-to-use treatment that is more often administered successfully. The economic impact of this usability advantage was explored in cost-offset and budget impact analyses for the US setting.

METHODS

A health economic model was developed to estimate mean costs per SHE for which treatment was attempted using NG or IG, which differed only in the probability of treatment success, based on a published usability study. The budget impact of NG was projected over 2 years for patients with type 1 diabetes (T1D) and type 2 diabetes treated with basal-bolus insulin (T2D-BB). Epidemiologic and cost data were sourced from the literature and/or fee schedules.

RESULTS

Mean costs were $992 lower if NG was used compared with IG per SHE for which a user attempted treatment. NG was estimated to reduce SHE-related spending by $1.1 million and $230 000 over 2 years in 10 000 patients each with T1D and T2D-BB, respectively. Reduced spending resulted from reduced professional emergency services utilization as successful treatment was more likely with NG.

CONCLUSIONS

The usability advantage of NG over IG was projected to reduce SHE-related treatment costs in the US setting. NG has the potential to improve hypoglycemia emergency care and reduce SHE-related treatment costs.

Human Factors Usability and Validation Studies of a Glucagon Autoinjector in a Simulated Severe Hypoglycemia Rescue Situation

Background: A room-temperature stable, soluble liquid glucagon formulation loaded into a prefilled, single-use, two-step autoinjector is under development for severe hypoglycemia rescue. We report a human factors validation program evaluating the glucagon autoinjector (GAI) (Gvoke HypoPen™; Xeris Pharmaceuticals, Inc., Chicago, IL) versus marketed glucagon emergency kits (GEKs) for managing severe hypoglycemia. Methods: A simulated-use human factors usability study was conducted with the GAI versus marketed GEKs in 16 participants, including adult caregivers and first responders, experienced with glucagon administration. A summative human factors validation study of the GAI was conducted with 75 volunteers. Participants were (1) trained on the device and procedure or (2) given time to individually read the instructions and familiarize themselves with the device. Participants returned a week later to perform an unaided rescue attempt that simulated rescue of patients with diabetes suffering a hypoglycemia emergency. Participant actions were recorded for critical rescue tasks and use errors. Results: In the usability study, 88% (14) successfully administered a rescue injection using the GAI versus 31% (5) using GEKs (P < 0.05). Mean total rescue time of use was 47.9 s with the GAI versus 109.0 s with GEKs (P < 0.05). In the validation study, 98.7% successfully administered the rescue injection using the GAI. Overall, there were no patterns of differences between trained versus untrained participants, between caregivers versus first responders or between adults versus adolescents. Conclusion: The GAI and instructional materials can be correctly, safely, and effectively used by intended user, which support continued development of the GAI as an alternative to GEKs.

Automated glycemic control with the bionic pancreas in cystic fibrosis-related diabetes: A pilot study

Cystic fibrosis-related diabetes (CFRD) is the most common extrapulmonary manifestation of cystic fibrosis. The current standard of care for CFRD involves treatment with insulin, typically via multiple daily injections. We conducted a small pilot study comparing usual care with automated glycemic control using the bihormonal (insulin and glucagon) and insulin-only configurations of the bionic pancreas. Both configurations of the bionic pancreas achieved good glycemic control, with mean glucose levels <150 mg/dl and minimal hypoglycemia. Subjects reported improved treatment satisfaction and reduced burden of diabetes management with the bionic pancreas. Further investigation of automated glycemic control in the treatment of CFRD is warranted.

Intranasal Glucagon

Glucagon is an essential drug, used for the management of hypoglycaemia. Currently available injectable preparations are cumbersome, difficult to use and not easily acceptable by many patients. Injection glucagon is also not available in all parts of the world. Intranasal glucagon offers a novel, effective and convenient mode of delivery of this emergency drug. This review covers the basic and clinical pharmacology of nasal glucagon, and describes its potential use in practice.

Therapeutic Use of Intranasal Glucagon: Resolution of Hypoglycemia

Episodes of hypoglycemia are frequent in patients with diabetes treated with insulin or sulphonylureas. Hypoglycemia can lead to severe acute complications, and, as such, both prevention and treatment of hypoglycemia are important for the well-being of patients with diabetes. The experience of hypoglycemia also leads to fear of hypoglycemia, that in turn can limit optimal glycemic control in patients, especially with type 1 diabetes. Treatment of hypoglycemia is still based on administration of carbohydrates (oral or parenteral according to the level of consciousness) or of glucagon (intramuscular or subcutaneous injection). In 1983, it was shown for the first time that intranasal (IN) glucagon drops (with sodium glycocholate as a promoter) increase blood glucose levels in healthy volunteers. During the following decade, several authors showed the efficacy of IN glucagon (drops, powders, and sprays) to resolve hypoglycemia in normal volunteers and in patients with diabetes, both adults and children. Only in 2010, based on evaluation of patients' beliefs and patients' expectations, a canadian pharmaceutical company (Locemia Solutions, Montreal, Canada) reinitiated efforts to develop glucagon for IN administration. The project has been continued by Eli Lilly, that is seeking to obtain registration in order to make IN glucagon available to insulin users (children and adolescents) worldwide. IN glucagon is as effective as injectable glucagon, and devoid of most of the technical difficulties associated with administration of injectable glucagon. IN glucagon appears to represent a major breakthrough in the treatment of severe hypoglycemia in insulin-treated patients with diabetes, both children and adults.

Glucose-Responsive Composite Microneedle Patch for Hypoglycemia-Triggered Delivery of Native Glucagon

Insulin-dependent patients with diabetes mellitus require multiple daily injections of exogenous insulin to combat hyperglycemia. However, administration of excess insulin can lead to hypoglycemia, a life-threatening condition characterized by abnormally low blood glucose levels (BGLs). To prevent hypoglycemia associated with intensive insulin therapy, a "smart" composite microneedle (cMN) patch is developed, which releases native glucagon at low glucose levels. The cMN patch is composed of a photo-crosslinked methacrylated hyaluronic acid (MeHA) microneedle array with embedded multifunctional microgels. The microgels incorporate zwitterionic moieties that stabilize loaded glucagon and phenylboronic acid moieties that provide glucose-dependent volume change to facilitate glucagon release. Hypoglycemia-triggered release of structurally unchanged glucagon from the cMN patch is demonstrated in vitro and in a rat model of type 1 diabetes (T1D). Transdermal application of the patch prevented insulin-induced hypoglycemia in the diabetic rats. This work is the first demonstration of a glucose-responsive glucagon-delivery MN patch for the prevention of hypoglycemia, which has a tremendous potential to reduce the dangers of intensive insulin therapy and improve the quality of life of patients with diabetes and their caregivers.

Intranasal glucagon acutely increases energy expenditure without inducing hyperglycaemia in overweight/obese adults

AIM

To assess the acute effects of 0.7 mg intranasal glucagon (ING) vs intranasal placebo (INP) on food intake and resting energy expenditure (REE).

METHODS

A single-blind, crossover study was conducted in 19 overweight/obese adults (15 men, 4 women). REE was assessed by indirect calorimetry over 90 minutes, after which appetite was assessed using a visual analogue scale, and ad libitum caloric intake was assessed. Plasma samples were obtained at baseline and at 15-minute intervals post-treatment up to 90 minutes.

RESULTS

ING increased total REE (INP 61.5 ± 1.2 kcal vs ING 69.4 ± 1.2 kcal; P = 0.027). There were no between-treatment differences in blood glucose, food intake and appetite. There were no adverse effects.

CONCLUSION

ING acutely increases REE without increasing plasma glucose. Longer term studies with multiple daily dosing will establish whether this affects body weight.

A brief interactive training with medical students improves their diabetes knowledge about hypoglycemia

BACKGROUND

Hypoglycemia is a severe clinical problem with physical and psychosocial implications for people with type 1 and type 2 diabetes. Medical students would benefit from formal education on how to treat hypoglycemia as well as how to administer glucagon in case of a severe hypoglycemic emergency. The purpose of this study was to assess the effectiveness of a brief training to improve medical students' knowledge and attitudes about diabetes, hypoglycemia, and glucagon administration.

METHODS

We conducted a feasibility study to assess the effectiveness of an interactive training session on diabetes education with an emphasis on hypoglycemia. We measured medical students' knowledge and attitudes toward diabetes, hypoglycemia, and glucagon before and after the training. We performed Chi-Square tests, paired t-tests, determined effect sizes using Cohen's d, and analyzed short answer responses via content and thematic analyses.

RESULTS

Two hundred and seventeen participants (age = 25.1 ± 2.3 years, 45.2% female, 78.3% white, 36.4% planned to pursue primary care, response rate of 94.3%) completed surveys. Following the training, participants' total knowledge scores improved by five percentage points to 82.6 ± 11.0% (t-value = 7.119, p < 0.001). We also observed positive improvements in the General Test scores to 82.3 ± 12.6% (t-value = 5.844, p < 0.001) and Insulin Use Test scores to 82.4 ± 17.4% (t-value = 4.103, p < 0.001). For the hypoglycemia test, participants averaged 55.7 ± 24.8% pre-training and 83.0 ± 22.4% post-training (t-value = 14.258, p < 0.001). Lastly, participants scored 87.6 ± 18.5% on the glucagon test after the training session. In addition, we observed positive improvements in all five diabetes attitudes subscales after the training, with the largest magnitude of change in the "Psychosocial impact of diabetes" subscale (t-value = 9.249, p < 0.001, Cohen's d = 0.60). Qualitatively, more participants recognized the severity of hypoglycemia after the training. They also learned how to approach diabetes from the patient's perspective and valued the clinically relevant and practical information provided during the training session, such as the "15-15 Rule."

CONCLUSIONS

Medical students need to learn about patients' everyday experiences of diabetes in order to have an understanding of and confidence to assess and treat hypoglycemia. These findings underscore the importance of training medical students on how to actively assess and manage the risk of hypoglycemia in people with diabetes.

Preserved glucose response to low-dose glucagon after exercise in insulin-pump-treated individuals with type 1 diabetes: a randomised crossover study

AIMS/HYPOTHESIS

This study aimed to compare the increase in plasma glucose after a subcutaneous injection of 200 μg glucagon given after 45 min of cycling with resting (study 1) and to investigate the effects of glucagon when injected before compared with after 45 min of cycling (study 2). We hypothesised that: (1) the glucose response to glucagon would be similar after cycling and resting; and (2) giving glucagon before the activity would prevent the exercise-induced fall in blood glucose during exercise and for 2 h afterwards.

METHODS

Fourteen insulin-pump-treated individuals with type 1 diabetes completed three visits in a randomised, placebo-controlled, participant-blinded crossover study. They were allocated by sealed envelopes. Baseline values were (mean and range): HbA_1c 54 mmol/mol (43-65 mmol/mol) or 7.1% (6.1-8.1%); age 45 years (23-66 years); BMI 26 kg/m² (21-30 kg/m²); and diabetes duration 26 years (8-51 years). At each visit, participants consumed a standardised breakfast 2 h prior to 45 min of cycling or resting. A subcutaneous injection of 200 μg glucagon was given before or after cycling or after resting. The glucose response to glucagon was compared after cycling vs resting (study 1) and before vs after cycling (study 2).

RESULTS

The glucose response to glucagon was higher after cycling compared with after resting (mean ± SD incremental peak: 2.6 ± 1.7 vs 1.8 ± 2.0 mmol/l, p = 0.02). As expected, plasma glucose decreased during cycling (-3.1 ± 2.8 mmol/l) but less so when glucagon was given before cycling (-0.9 ± 2.8 mmol/l, p = 0.002). The number of individuals reaching glucose values ≤3.9 mmol/l was the same on the 3 days.

CONCLUSIONS/INTERPRETATION

Moderate cycling for 45 min did not impair the glucose response to glucagon compared with the glucose response after resting. The glucose fall during cycling was diminished by a pre-exercise injection of 200 μg glucagon; however, no significant difference was seen in the number of events of hypoglycaemia.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02882737 FUNDING: The study was funded by the Danish Diabetes Academy founded by Novo Nordisk foundation and by an unrestricted grant from Zealand Pharma.

Low doses of dasiglucagon consistently increase plasma glucose levels from hypoglycaemia and euglycaemia in people with type 1 diabetes mellitus

AIM

To characterize the pharmacokinetic and pharmacodynamic properties of dasiglucagon, a novel, stable and liquid formulated glucagon analogue, during hypoglycaemic and euglycaemic conditions in adult patients with type 1 diabetes mellitus.

RESEARCH DESIGN AND METHODS

In this randomized double-blind trial, 17 patients received four single subcutaneous doses (0.03, 0.08, 0.2 and 0.6 mg) of dasiglucagon (4 mg/mL formulation) under euglycaemic (plasma glucose [PG] 5.6 mmol/L [100 mg/dL]) or hypoglycaemic (PG 3.1-3.7 mmol/L [56-66 mg/dL]) conditions. For comparison, three doses (0.03, 0.08 and 0.2 mg) of a commercial glucagon formulation (Eli Lilly) were investigated at euglycaemia.

RESULTS

Dasiglucagon led to a dose-dependent and rapid increase in PG levels across all doses tested (mean increases 30 minutes post-dosing of 2.2 to 4.4 mmol/L [39-80 mg/dL] from euglycaemia and 1.3 to 5.2 mmol/L [24-94 mg/dL] from hypoglycaemia), which was higher than the rises elicited by similar doses of commercial glucagon (1.7-3.9 mmol/L [30-71 mg/dL]). The median time (range) to an increase in PG of >1.1 mmol/L (20 mg/dL) was <20 (18-19.5) minutes with 0.03 mg dasiglucagon and, with higher doses, the median times ranged from 9 to 15 minutes (commercial glucagon 13-14 minutes). In hypoglycaemia, 0.03 and 0.08 mg dasiglucagon re-established normoglycaemia (PG ≥3.9 mmol/L [70 mg/dL]) within median times of 14 and 10 minutes, respectively. Nausea and vomiting occurred more frequently with dasiglucagon than with commercial glucagon at identical doses which might be attributable to dasiglucagon's higher potency.

CONCLUSION

Dasiglucagon rapidly increased PG at doses of 0.03 to 0.6 mg in a dose-dependent manner and, therefore, is a good candidate for use in dual-hormone artificial pancreas systems.

Glucagon infusion alters the hyperpolarized 13 C-urea renal hemodynamic signature

Renal urea handling is central to the urine concentrating mechanism, and as such the ability to image urea transport in the kidney is an important potential imaging biomarker for renal functional assessment. Glucagon levels associated with changes in dietary protein intake have been shown to influence renal urea handling; however, the exact mechanism has still to be fully understood. Here we investigate renal function and osmolite distribution using [¹³ C,¹⁵ N] urea dynamics and ²³ Na distribution before and 60 min after glucagon infusion in six female rats. Glucagon infusion increased the renal [¹³ C,¹⁵ N] urea mean transit time by 14%, while no change was seen in the sodium distribution, glomerular filtration rate or oxygen consumption. This change is related to the well-known effect of increased urea excretion associated with glucagon infusion, independent of renal functional effects. This study demonstrates for the first time that hyperpolarized ¹³ C-urea enables monitoring of renal urinary excretion effects in vivo.

Association of fatty pancreas with pancreatic endocrine and exocrine function

Aim

The purpose of this study was to clarify whether fatty pancreas might lead to impaired pancreatic endocrine or exocrine function.

Material and methods

The study involved 109 participants who had undergone the glucagon stimulation test and N-benzoyl-L-tyros-p-amino benzoic acid (BT-PABA) test to assess pancreatic function as well as unenhanced abdominal computed tomography (CT). Pancreatic endocrine impairment was defined as ΔC peptide immunoreactivity less than 2 [mmol/L] in the glucagon stimulation test, and pancreatic exocrine impairment was defined as a urinary PABA excretion rate less than 70% on the BT-PABA test. We defined as the mean CT value of pancreas / CT value of spleen (P/S ratio) as a marker to assess fatty pancreas. We analyzed the association between fatty pancreas and pancreatic impairment using the logistic regression model. The odds ratio (OR) is shown per 0.1 unit.

Results

Pancreatic endocrine function was impaired in 33.0% of the participants, and 56.9% of those were regarded as having pancreatic exocrine impairment. The P/S ratio was significantly correlated with pancreatic endocrine impairment in univariate analysis (OR = 0.61, 95% confidence interval (CI) = 0.43–0.83, P = 0.0013) and multivariate analysis (OR = 0.38, 95% CI = 0.22–0.61, P < .0001) for all participants. Similar significant relationships were observed in both univariate (OR = 0.70, 95% CI = 0.49–0.99, P = 0.04) and multivariate (OR = 0.39, 95% CI = 0.21–0.66, P = 0.0002) analyses for the participants without diabetes (n = 93). The amount of pancreatic fat was not associated with exocrine impairment in univariate analysis (OR = 0.80, 95% CI = 0.59–1.06, P = 0.12).

Conclusion

Fatty pancreas was associated with pancreatic endocrine impairment but did not have a clear relationship with pancreatic exocrine impairment.

Insulin deficiency with and without glucagon: A comparative study between total pancreatectomy and type 1 diabetes

AIMS/INTRODUCTION

Patients with a total pancreatectomy and type 1 diabetes are similar in regard to absolute insulin deficiency, but different in regard to glucagon, providing a unique opportunity to study the contribution of glucagon to glucose metabolism in an insulin-dependent state. The aim of the present study was to investigate the contribution of glucagon to glucose homeostasis in complete insulin deficiency in vivo.

METHODS

A total of 38 individuals with a complete lack of endogenous insulin (fasting C-peptide <0.0066 nmol/L) and whose glycemic control was optimized with an insulin pump during hospitalization were retrospectively studied. The basal insulin requirement, time-to-time adjustment of the basal insulin infusion rate, prandial insulin requirement and fasting plasma glucagon were compared between patients with a total pancreatectomy (n = 10) and those with type 1 diabetes (n = 28) after achievement of optimal glycemic control.

RESULTS

Total daily insulin (P = 0.03) and basal insulin (P = 0.000006), but not prandial insulin requirements, were significantly lower in total pancreatectomy patients than in type 1 diabetes patients. The basal percentage (basal insulin/total daily insulin) was also significantly lower in total pancreatectomy patients than in type 1 diabetes patients (15.8 ± 7.8 vs 32.9 ± 10.1%, P = 0.00003). An increase in the insulin infusion rate early in the morning was not necessary in most patients with a pancreatectomy. The fasting plasma glucagon concentration was significantly lower in total pancreatectomy patients than in type 1 diabetes patients (P = 0.00007), and was positively correlated with the basal insulin requirement (P = 0.038).

CONCLUSIONS

The difference in insulin requirements between total pancreatectomy and type 1 diabetes patients suggests a contribution of glucagon to the basal insulin requirement and dawn phenomenon.

[Technological Innovations in Diabetes Therapy]

Technological Innovations in Diabetes Therapy Abstract. In the last few years a whole array of technical innovations has dramatically increased treatment options for patients with diabetes mellitus. Capillary blood glucose measurements are increasingly replaced by continuous glucose monitoring. More and more insulin pump systems are linked up to continuous glucose monitoring, which thereby become ever more self-regulating. Novel ultra-long and ultra-short acting insulins have become available. There will soon be oral alternatives for several anti-diabetic treatments, which hitherto needed to be injected.

Intranasal glucagon for hypoglycaemia in diabetic patients. An old dream is becoming reality?

In 1983 it was shown that glucagon administered intranasally (IN) was absorbed through the nasal mucosa and increased blood glucose in healthy subjects. Shortly thereafter, it was shown that IN glucagon counteracts with hypoglycaemia in insulin-treated diabetic patients. In spite of this evidence, IN glucagon was not developed by any pharmaceutical company before 2010, when renewed interest led to intensive evaluation of a possible remedy for hypoglycaemia in insulin-treated diabetic adults and children. IN glucagon is now being developed as a needle-free device that delivers glucagon powder for treatment of severe hypoglycaemia; the ease of using this device stands in stark contrast to the difficulties encountered in use of the current intramuscular glucagon emergency kits. Studies have demonstrated the efficacy, safety and ease-of-use of this IN glucagon preparation, and suggest IN glucagon as a promising alternative to injectable glucagon for treating severe hypoglycaemia in children and adults who use insulin. This would meet the unmet medical need for an easily administered glucagon preparation.

Stable Liquid Glucagon: Beyond Emergency Hypoglycemia Rescue

Glycemic control is the mainstay of preventing diabetes complications at the expense of increased risk of hypoglycemia. Severe hypoglycemia negatively impacts the quality of life of patients with type 1 diabetes and can lead to morbidity and mortality. Currently available glucagon emergency kits are effective at treating hypoglycemia when correctly used, however use is complicated especially by untrained persons. Better formulations and devices for glucagon treatment of hypoglycemia are needed, specifically stable liquid glucagon. Out of the scope of this review, other potential uses of stable liquid glucagon include congenital hyperinsulinism, post-bariatric surgery hypoglycemia, and insulinoma induced hypoglycemia. In the 35 years since Food and Drug Administration (FDA) approval of the first liquid stable human recombinant insulin, we continue to wait for the glucagon counterpart. For mild hypoglycemia, a commercially available liquid stable glucagon would enable more widespread implementation of mini-dose glucagon use as well as glucagon in dual hormone closed-loop systems. This review focuses on the current and upcoming pharmaceutical uses of glucagon in the treatment of type 1 diabetes with an outlook on stable liquid glucagon preparations that will hopefully be available for use in patients in the near future.

Complete loss of insulin secretion capacity in type 1A diabetes patients during long-term follow up

AIM/INTRODUCTION

Patients with type 1 diabetes are classified into three subtypes in Japan: acute onset, fulminant and slowly progressive. Acute-onset type 1 diabetes would be equivalent to type 1A diabetes, the typical type 1 diabetes in Western countries. The insulin secretion capacity in Japanese patients with long-standing type 1A diabetes is unclear. The aim of the present study was to clarify the course of endogenous insulin secretion during long-term follow up and the factors associated with residual insulin secretion in patients with acute-onset type 1 diabetes (autoimmune).

MATERIALS AND METHODS

We retrospectively investigated endogenous insulin secretion capacity in 71 patients who fulfilled the diagnostic criteria for acute-onset type 1 diabetes (autoimmune) in Japan. To assess the residual insulin secretion capacity, we evaluated randomly measured C-peptide levels and the results of glucagon stimulation test in 71 patients.

RESULTS

In the first year of disease, the child- and adolescent-onset patients had significantly more in residual insulin secretion than the adult-onset patients (34 patients in total). C-peptide levels declined more rapidly in patients whose age of onset was ≤18 years than in patients whose age of onset was ≥19 years. Endogenous insulin secretion capacity stimulated by glucagon was completely lost in almost all patients at >15 years after onset (61 patients in total).

CONCLUSIONS

Most patients with acute-onset type 1 diabetes (autoimmune) completely lose their endogenous insulin secretion capacity during the disease duration in Japan. Age of onset might affect the course of insulin secretion.