Glucagon for hypoglycaemia treatment in type 1 diabetes

Corrination mitigates peptide aggregation as exemplified for Glucagon

Pharmaceutical development of glucagon for use in acute hypoglycemia has proved challenging, due in large part to poor solubility, poor stability and aggregate formation. Herein, we describe highly soluble, low aggregating, glucagon conjugates generated through use of the commercially available vitamin B12 precursor dicyanocobinamide ('corrination'), which retain full stimulatory action at the human glucagon receptor. The modified glucagon analogs were tested in a chemical stability assay in 50 mM phosphate buffer and the percentage of original concentration retained was determined after two weeks of incubation at 37° C. Aggregate formation assays were also performed after 48 h of agitation at 37°C using a thioflavin (ThT) fluorescence-based assay. All corrinated compounds retained original concentration to a higher degree than glucagon controls and showed markedly decreased aggregation compared to their respective noncorrinated analogues. Based on the statistically significant increase in chemical stability coupled with the notably decreased tendency to form aggregates, analogues 2 and its corrinated conjugate 5 were used for a functional assay study performed after agitation at 37°C for 24-hr after which agonism was measured at the human glucagon receptor using a cAMP FRET assay. Corrinated 5 exhibited a 6.6-fold increased potency relative to glucagon, which was shown to have a 165-fold reduction in potency. The relative potency of 5 was also improved compared to that of 2 with EC50 values of 5.5 nM and 9.6 nM for 5 and 2, respectively. In conclusion, corrination of peptides mitigates aggregation, presenting a compound with prolonged stability and agonism as demonstrated for glucagon.

Practicality of non-invasive glucagon-loaded dissolving microneedle for life-saving treatment of severe hypoglycemia in a diabetic rat model

The development of dissolving microneedles (DMNs) has brought light to the transdermal delivery of biomolecules that are released into the skin through the rapid dissolution of the matrix material to enter the systemic circulation and exert therapeutic effects. Herein, we aimed to prepare, characterize, and analyze the effectiveness of a glucagon-loaded DMN system that rapidly increases blood sugar levels in rats with diabetic hypoglycemia. The stability and content of biological drugs following DMNs preparation was assessed using circular dichroism and bicinchoninic acid kit for protein determination kits(BCA kits). The maximum drug loading capacity of DMNs was approximately 140 μg in each patch, and the microneedles could be stored for up to 14 days under dry storage conditions. In vitro skin permeation studies were conducted using a Franz diffusion cell apparatus for glucagon-loaded DMNs. To investigate the efficacy of transdermal drug delivery, drug-laden DMNs were administered to rats with hypoglycemic diabetes. Compared to subcutaneous injections, microneedle drug release demonstrated comparable efficacy in raising blood glucose levels in vivo. Therefore, this study demonstrated that glucagon-loaded DMNs may be a promising approach for efficient transdermal drug delivery as an alternative to subcutaneous injection for the treatment of severe hypoglycemia in patients with diabetes.

Performance of a dual-hormone closed-loop system versus insulin-only closed-loop system in adolescents with type 1 diabetes. A single-blind, randomized, controlled, crossover trial

Objective

To assess the efficacy and safety of a dual-hormone (DH [insulin and glucagon]) closed-loop system compared to a single-hormone (SH [insulin only]) closed-loop system in adolescents with type 1 diabetes.

Methods

This was a 26-hour, two-period, randomized, crossover, inpatient study involving 11 adolescents with type 1 diabetes (nine males [82%], mean ± SD age 14.8 ± 1.4 years, diabetes duration 5.7 ± 2.3 years). Except for the treatment configuration of the DiaCon Artificial Pancreas: DH or SH, experimental visits were identical consisting of: an overnight stay (10:00 pm until 7:30 am), several meals/snacks, and a 45-minute bout of moderate intensity continuous exercise. The primary endpoint was percentage of time spent with sensor glucose values below range (TBR [<3.9 mmol/L]) during closed-loop control over the 26-h period (5:00 pm, day 1 to 7:00 pm, day 2).

Results

Overall, there were no differences between DH and SH for the following glycemic outcomes (median [IQR]): TBR 1.6 [0.0, 2.4] vs. 1.28 [0.16, 3.19]%, p=1.00; time in range (TIR [3.9-10.0 mmol/L]) 68.4 [48.7, 76.8] vs. 75.7 [69.8, 87.1]%, p=0.08; and time above range (TAR [>10.0 mmol/L]) 28.1 [18.1, 49.8] vs. 23.3 [12.3, 27.2]%, p=0.10. Mean ( ± SD) glucose was higher during DH than SH (8.7 ( ± 3.2) vs. 8.1 ( ± 3.0) mmol/L, p<0.001) but coefficient of variation was similar (34.8 ( ± 6.8) vs. 37.3 ( ± 8.6)%, p=0.20). The average amount of rescue carbohydrates was similar between DH and SH (6.8 ( ± 12.3) vs. 9.5 ( ± 15.4) grams/participant/visit, p=0.78). Overnight, TIR was higher, TAR was lower during the SH visit compared to DH. During and after exercise (4:30 pm until 7 pm) the SH configuration produced higher TIR, but similar TAR and TBR compared to the DH configuration.

Conclusions

DH and SH performed similarly in adolescents with type 1 diabetes during a 26-hour inpatient monitoring period involving several metabolic challenges including feeding and exercise. However, during the night and around exercise, the SH configuration outperformed DH.

Low-Dose Dasiglucagon Versus Oral Glucose for Prevention of Insulin-Induced Hypoglycemia in People With Type 1 Diabetes: A Phase 2, Randomized, Three-Arm Crossover Study

OBJECTIVE

To compare the efficacy of low-dose subcutaneous dasiglucagon with oral glucose for prevention of insulin-induced hypoglycemia in people with type 1 diabetes.

RESEARCH DESIGN AND METHODS

Twenty adults with type 1 diabetes using multiple daily injection or insulin pump therapy completed a phase 2, randomized, three-arm crossover study. On each study visit, an individualized subcutaneous insulin bolus was administered aiming for a plasma glucose (PG) concentration of 3.0 mmol/L (54 mg/dL). When a PG concentration of 4.5 mmol/L (81 mg/dL) was reached, 15 g oral glucose (CHO) from dextrose tablets, 80 µg dasiglucagon (D80), or 120 µg dasiglucagon (D120) was administered. PG was measured frequently for the following 180 min.

RESULTS

Hypoglycemia (<3.9 mmol/L [70 mg/dL]) occurred in 10 participants after CHO, in 5 after D80, and in 4 after D120 (CHO vs. D80, P = 0.096; CHO vs. D120, P = 0.034). Time spent in hypoglycemia (<3.9 mmol/L [70 mg/dL]) was 14%, 7%, and 6% for CHO, D80, and D120, respectively (P = 0.273). The median time (95% CI) from intervention to first increase in PG of 1.1 mmol/L (20 mg/dL) was 30 (25-50), 15 (15-20), and 15 (15-20) minutes for CHO, D80, and D120, respectively (CHO vs. D80, P = 0.006; CHO vs. D120, P = 0.003). Episodes of nausea were numerically, but not significantly, higher after dasiglucagon administration. No significant differences in visual analog scale-assessed adverse effects were observed between interventions.

CONCLUSIONS

Low-dose dasiglucagon safely and effectively prevented insulin-induced hypoglycemia with a faster glucose-elevating profile than oral glucose.