The effects of HDV-insulin on carbohydrate metabolism in Type 1 diabetic patients

Reduced hypoglycaemia using liver-targeted insulin in individuals with type 1 diabetes

AIM

To investigate whether an increased bolus: basal insulin ratio (BBR) with liver-targeted bolus insulin (BoI) would increase BoI use and decrease hypoglycaemic events (HEv).

PATIENT POPULATION AND METHODS

We enrolled 52 persons (HbA1c 6.9% ± 0.12%, mean ± SEM) with type 1 diabetes using multiple daily injections. Hepatic-directed vesicle (HDV) was used to deliver 1% of peripheral injected BoI to the liver. A 90-day run-in period was used to introduce subjects to unblinded continuous glucose monitoring and optimize standard basal insulin (BaI) (degludec) and BoI (lispro) dosing. At 90 days, BoI was changed to HDV-insulin lispro and subjects were randomized to an immediate 10% or 40% decrease in BaI dose.

RESULTS

At 90 days postrandomization, total insulin dosing was increased by ~7% in both cohorts. The -10% and -40% BaI cohorts were on 7.7% and 13% greater BoI with 6.9% and 30% (P = .02) increases in BBR, respectively. Compared with baseline at randomization, nocturnal level 2 HEv were reduced by 21% and 43%, with 54% and 59% reductions in patient-reported HEv in the -10% and -40% BaI cohorts, respectively.

CONCLUSIONS

Our study shows that liver-targeted BoI safely decreases HEv and symptoms without compromising glucose control. We further show that with initiation of liver-targeted BoI, the BBR can be safely increased by significantly lowering BaI dosing, leading to greater BoI usage.

Divergent Hypoglycemic Effects of Hepatic-Directed Prandial Insulin: A 6-Month Phase 2b Study in Type 1 Diabetes

OBJECTIVE

Hepatic-directed vesicle insulin (HDV) uses a hepatocyte-targeting moiety passively attaching free insulin, improving subcutaneous insulin's hepatic biodistribution. We assessed HDV-insulin lispro (HDV-L) versus insulin lispro (LIS) in type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

Insulin Liver Effect (ISLE-1) was a 26-week, phase 2b, multicenter, randomized, double-blind, noninferiority trial.

RESULTS

Among 176 randomized participants (HDV-L n = 118, LIS n = 58), the difference in change from baseline A1C was 0.09% (95% CI -0.18% to 0.35%), confirming noninferiority (prespecified margin ≤0.4%). Overall, there were no statistically significant differences between treatments for hypoglycemia or insulin dosing. However, baseline A1C modified the treatment group effect (interaction P < 0.001) on clinically apparent hypoglycemia designated by treatment-blinded investigators as severe. Thus, at higher baseline A1C, there was less hypoglycemia and lower insulin dosing with similar A1C outcomes during HDV-L versus LIS, whereas greater risk of hypoglycemia despite similar A1C outcomes and insulin doses was observed with lower baseline A1C. Among poorly controlled participants (A1C ≥8.5%), incidence rates of severe hypoglycemia in the HDV-L and LIS arms were 69 and 97 events/100 person-years, respectively (P = 0.03), whereas with A1C <8.5%, respective rates were 191 and 21 events/100 person-years (P = 0.001). Similar A1C-dependent trends in hypoglycemia were seen with continuous glucose monitoring. Among poorly controlled participants, bolus insulin doses at end point were ∼25% lower with HDV-L (P = 0.02), despite similar A1C outcomes; in better-controlled participants, insulin doses and A1Cs were stable over time in both subgroups. No safety signals were identified.

CONCLUSIONS

Hepatic biodistribution of HDV-L appears to potentiate insulin effect in T1D, with divergent clinical outcomes in hypoglycemia dependent on baseline A1C.

Addressing Unmet Medical Needs in Type 1 Diabetes: A Review of Drugs Under Development

The incidence of type 1 diabetes (T1D) is increasing worldwide and there is a very large need for effective therapies. Essentially no therapies other than insulin are currently approved for the treatment of T1D. Drugs already in use for type 2 diabetes and many new drugs are under clinical development for T1D, including compounds with both established and new mechanisms of action. Content of the Review: Most of the new compounds in clinical development are currently in Phase 1 and 2. Drug classes discussed in this review include new insulins, SGLT inhibitors, GLP-1 agonists, immunomodulatory drugs including autoantigens and anti-cytokines, agents that regenerate β-cells and others. Regulatory Considerations: In addition, considerations are provided with regard to the regulatory environment for the clinical development of drugs for T1D, with a focus on the United States Food and Drug Administration and the European Medicines Agency. Future opportunities, such as combination treatments of immunomodulatory and beta-cell regenerating therapies, are also discussed.

A single-blind, placebo-controlled, dose-ranging trial of oral hepatic-directed vesicle insulin add-on to oral antidiabetic treatment in patients with type 2 diabetes mellitus

The dose response of postprandial plasma glucose (PPG) to add-on, premeal oral hepatic-directed vesicle-insulin (HDV-I), an investigational lipid bio-nanoparticle hepatocyte-targeted insulin delivery system, was evaluated in a 3-test-meal/day model in type 2 diabetes patients. The single-blind, placebo-controlled, dose-escalating trial enrolled 6 patients with HbA(1c) 8.6 ± 2.0% (70.0 ± 21.9 mmol/mol) and on stable metformin therapy. Patients received oral HDV-I capsules daily 30 minutes before breakfast, lunch, and dinner as follows: placebo capsules, 0.05, 0.1, 0.2, and 0.4 U/kg on days 1, 2, 3, 4, and 5, respectively. Outcome measures were PPG and incremental PPG area under the concentration-time curve (AUC). All 4 doses of oral HDV-I statistically significantly lowered mean PPG (P ≤ .0110 each) and incremental PPG (P ≤ .0352 each) AUC compared to placebo. A linear dose response was not observed. The 0.05 U/kg dose was the minimum effective dose in the dosage range studied. Three adverse events unrelated to treatment were observed. Add-on oral HDV-I 0.05-0.4 U/kg significantly lowered PPG excursions and the dose response curve was flat. These results are consistent with the lack of a linear dose response between portal and systemic plasma insulin concentrations in previous animal and human studies. Oral HDV-I was safe and well tolerated.

Hepatic-directed vesicle insulin: a review of formulation development and preclinical evaluation

Hepatic-directed vesicle insulin (HDV-I), a novel investigational vesicle (<150 nm diameter) insulin delivery system that carries insulin and a specific hepatocyte-targeting molecule (HTM) in its phospholipid bilayer and has the ability to mimic a portal vein insulin infusion remotely [subcutaneous (SC) HDV-I] and noninvasively (oral HDV-I), has been developed. This review summarizes formulation development, subsequent refinements, and results of preclinical evaluation studies, including biodistribution, mechanistic, and toxicology studies of predominantly SC HDV-I, in various animal models. Studies conducted to date have confirmed the hepatocyte specificity of HDV and HDV-I and revealed that HDV-I can stimulate the conversion of hepatic glucose output to uptake at a dose that is <1% of the dose of regular insulin (RI) required for liver stimulation; suggest that the enhanced antihyperglycemic effect of HDV-I is due to hepatic glucose uptake; and in pancreatectomized dogs during an oral glucose tolerance test, HDV-I normalized blood glucose curves when compared to control curves in intact dogs and prevented secondary hypoglycemia in contrast to the same dose of RI. A 28-day SC HDV toxicity study in rats revealed no clinical, clinical laboratory, or histopathological findings, and the battery of three genetic toxicology studies was negative. Results support the hypothesis that HDV-I works by stimulating hepatic glucose uptake and/or glycogen storage in insulin-deficient animals. The ability to target the delivery of HDV-I to the liver reestablishes the liver as a major metabolic modulator of glucose metabolism. The future of HDV-I depends on the results of ongoing development and longer term clinical trials.

Oral insulin and buccal insulin: a critical reappraisal

Despite the availability of modern insulin injection devices with needles that are so sharp and thin that practically no injection pain takes place, it is still the dream of patients with diabetes to, for example, swallow a tablet with insulin. This is not associated with any pain and would allow more discretion. Therefore, availability of oral insulin would not only ease insulin therapy, it would certainly increase compliance. However, despite numerous attempts to develop such a "tablet" in the past 85 years, still no oral insulin is commercially available. Buccal insulin is currently in the last stages of clinical development by one company and might become available in the United States and Europe in the coming years (it is already on the market in some other countries). The aim of this review is to critically describe the different approaches that are currently under development. Optimal coverage of prandial insulin requirements is the aim with both routes of insulin administration (at least with most approaches). The speed of onset of metabolic effect seen with some oral insulin approaches is rapid, but absorption appears to be lower when the tablet is taken immediately prior to a meal. With all approaches, considerable amounts of insulin have to be applied in order to induce therapeutically relevant increases in the metabolic effect because of the low relative biopotency of buccal insulin. Unfortunately, the number of publications about clinical-experimental and clinical studies is surprisingly low. In addition, there is no study published in which the variability of the metabolic effect induced (with and without a meal) was studied adequately. In summary, after the failure of inhaled insulin, oral insulin and buccal insulin are hot candidates to come to the market as the next alternative routes of insulin administration.

A novel per-oral insulin formulation: proof of concept study in non-diabetic subjects

AIMS

The aim of our study was to examine the absorption of insulin from the gastrointestinal (GI) tract, using a novel oral formulation-adding a delivery agent SNAC (sodium N-[8-(2-hydroxybenzoyl)amino] caprylate) in combination with insulin.

METHODS

Capsules containing insulin and SNAC, in various combinations, were administered orally, as a single dose, to 12 non-diabetic subjects and four control subjects (receiving SNAC or insulin only) in order to assess its biological effect and safety. Plasma glucose levels, insulin and C-peptide concentrations, as well as SNAC levels, were determined, at timed intervals up to 4 h.

RESULTS

In all cases, a glucose-lowering effect was demonstrated, preceded by an increase in plasma insulin levels. The nadir of plasma glucose levels appeared after 30-50 min, following the ingestion of the mixture. The plasma insulin levels were found to parallel the blood SNAC levels. Plasma C-peptide levels were suppressed by the lowered glucose levels achieved concurrent with the increasing amount of exogenous insulin absorbed, indicating that the secretion of endogenous hormone was partially abolished. There were no biological effects regarding blood glucose levels upon administration of SNAC or insulin when given alone. No adverse effects were detected during the trial or several weeks after the trial.

CONCLUSIONS

Insulin in combination with a novel delivery agent, SNAC, given orally, is absorbed through the GI tract in a biologically active form. This was demonstrated by a glucose lowering effect of the mixture as well as a suppression of an endogenous insulin secretion.

Estrogen blunts neuroendocrine and metabolic responses to hypoglycemia

This study tested the hypothesis that estrogen is the mechanism responsible for the sexual dimorphism present in the neuroendocrine and metabolic responses to hypoglycemia. Postmenopausal women receiving (E2; n = 8) or not receiving (NO E2; n = 9) estrogen replacement were compared with age- and BMI-matched male subjects (n = 8) during a single-step 2-h hyperinsulinemic-hypoglycemic clamp. Plasma insulin (599 +/- 28 pmol/l) and glucose (2.9 +/- 0.03 mmol/l) levels were similar among all groups during the glucose clamp. In response to hypoglycemia, epinephrine (2.8 +/- 0.6 vs. 5.8 +/- 0.8 and 4.4 +/- 0.5 nmol/l), glucagon (57 +/- 8 vs. 77 +/- 8 and 126 +/- 18 ng/l), and endogenous glucose production (2 +/- 2 vs. 10 +/- 2 and 6 +/- 3 micro mol x kg(-1) x min(-1)) were significantly lower in E2 vs. both NO E2 and male subjects (P < 0.05). These reduced counterregulatory responses resulted in significantly greater glucose infusion rates (16 +/- 2 vs. 6 +/- 2 and 6 +/- 3 micro mol x kg(-1) x min(-1); P < 0.01) in E2 vs. both NO E2 and male subjects. Pancreatic polypeptide was significantly lower (P < 0.05) in both the E2 and NO E2 groups compared with the male subjects (136 +/- 20 and 136 +/- 23 vs. 194 +/- 16 pmol/l). Last, glycerol (36 +/- 3 vs. 47 +/- 5 micro mol/l; P < 0.05), lactate (1.4 +/- 0.1 vs. 1.8 +/- 0.2 mmol/l; P < 0.05), and muscle sympathetic nerve activity (19 +/- 4 to 27 +/- 4 vs. 27 +/- 5 to 42 +/- 6 bursts/min; P < 0.05) responses to hypoglycemia were all significantly lower in E2 vs. NO E2 subjects. We conclude that estrogen appears to play a major role in the sexual dimorphism present in counterregulatory responses to hypoglycemia in healthy humans.