Lessons for modern insulin development

Injectable systems for long-lasting insulin therapy

Insulin therapy is the mainstay to treat diabetes characterizedd by hyperglycemia. However, its short half-life of only 4-6 min limits its effectiveness in treating chronic diabetes. Advances in recombinant DNA technology and protein engineering have led to several insulin analogue products that have up to 42 h of glycemic control. However, these insulin analogues still require once- or twice-daily injections for optimal glycemic control and have poor patient compliance and adherence issues. To achieve insulin release for more than one day, different injectable delivery systems including microspheres, in situ forming depots, nanoparticles and composite systems have been developed. Several of these delivery systems have advanced to clinical trials for once-weekly insulin injection. This review comprehensively summarizes the developments of injectable insulin analogs and delivery systems covering the whole field of injectable long-lasting insulin technologies from prototype design, preclinical studies, clinical trials to marketed products for the treatment of diabetes.

Discovery of insulin 100 years on

The discovery of insulin 100 years ago ranks among the greatest medical achievements ever. This sparked a revolution of scientific discovery and therapeutic intervention to treat people suffering with diabetes. A light was shone for other areas of medicine to illuminate what was possible with detailed scientific endeavour. There followed a range of firsts leading to the current time in which we now know more about this peptide hormone than almost any other protein in existence. This has allowed therapeutic advancement from a positon of knowledge leading to stunning innovation. This innovation is likely to lead to more physiological insulin replacement reducing the disease burden to individuals and society as whole.

Advances in buccal and oral delivery of insulin

Diabetes mellitus is a metabolic endocrine disease characterized by chronic hyperglycemia with disturbances in metabolic processes, such as those related to carbohydrates, fat, and protein. There are two main types of this disease: type 1 diabetes (T1D) and type 2 diabetes (T2D). Insulin therapy is pivotal to the management of diabetes. Over the last two decades, many routes of administration, including nasal, pulmonary, rectal, transdermal, buccal, and ocular, have been investigated. Nevertheless, subcutaneous parenteral administration is still the most common route for insulin therapy. To overcome poor bioavailability and the barriers to oral insulin absorption, novel approaches in the field of oral drug delivery and administration have been brought about by the coalescence of different branches of nanoscience and nanotechnology, such as nanomedicine, nano-biochemistry, and nano-pharmacy. Novel drug delivery systems, including nanoparticles, nano-platforms, and nanocarriers, have been suggested. The objective of this review is to provide an update on the various promising approaches that have been explored and evaluated for the safe and efficient oral and buccal administration of insulin.

Basal insulin analogues in people with diabetes and chronic kidney disease

BACKGROUND

Diabetic kidney disease is the leading cause of chronic kidney disease (CKD) and end-stage kidney disease (ESKD) worldwide. ESKD has a high prevalence in patients with diabetes mellitus (DM). CKD increases the chances of hypoglycaemia by different mechanisms, causes insulin resistance and a decrease in insulin metabolism. Both the "Kidney Disease: Improving Global Outcomes" (KDIGO) and "American Diabetes Association" (ADA) guidelines recommend the use of insulin as part of treatment, but the type of basal insulin is not specified.

METHODS

We reviewed the literature to determine whether first- and second-generation basal insulins are effective and safe in CKD patients. We reviewed specific pivotal studies conducted by pharmaceutical laboratories, as well as independent studies.

CONCLUSIONS

Basal insulins are safe and effective in patients with CKD and diabetes mellitus but we do not have specific studies. Given that CKD is one of the main complications of type 2 DM, and insulin specific treatment in the final stages, the absence of studies is striking. Real-life data are also important since trials such as pivotal studies do not fully represent actual patients. Treatment should be individualized until we have specific trials in this type of population.

Insulin Analogues with Altered Insulin Receptor Isoform Binding Specificities and Enhanced Aggregation Stabilities

Insulin is a lifesaver for millions of diabetic patients. There is a need for new insulin analogues with more physiological profiles and analogues that will be thermally more stable than human insulin. Here, we describe the chemical engineering of 48 insulin analogues that were designed to have changed binding specificities toward isoforms A and B of the insulin receptor (IR-A and IR-B). We systematically modified insulin at the C-terminus of the B-chain, at the N-terminus of the A-chain, and at A14 and A18 positions. We discovered an insulin analogue that has Cα-carboxyamidated Glu at B31 and Ala at B29 and that has a more than 3-fold-enhanced binding specificity in favor of the "metabolic" IR-B isoform. The analogue is more resistant to the formation of insulin fibrils at 37 °C and is also more efficient in mice than human insulin. Therefore, [AlaB29,GluB31,amideB31]-insulin may be interesting for further clinical evaluation.

The promising future of insulin therapy in diabetes mellitus

The first therapeutic use of insulin by Frederick Banting and Charles Best in 1921 revolutionized the management of type 1 diabetes and considerably changed the lives of many patients with other types of diabetes. In the past 100 years, significant pharmacological advances took place in the field of insulin therapy, bringing closer the goal of optimal glycemic control along with decreased diabetes-related complications. Despite these developments, several challenges remain, such as increasing treatment flexibility, reducing iatrogenic hypoglycemia, and optimizing patient quality of life. Ongoing innovations in insulin therapy (e.g., new insulin analogs, alternative routes of insulin administration, and closed-loop technology) endeavor to overcome these hurdles and change the landscape of diabetes mellitus management. This report highlights recent advances made in the field of insulin therapy and discusses future perspectives.

Efficacy and safety of fast-acting insulin aspart versus insulin aspart in children and adolescents with type 1 diabetes from Japan

The aim of this post-hoc subgroup analysis, which was based on data from the treat-to-target, 26-week, onset 7 trial, was to confirm the efficacy and safety of fast-acting insulin aspart (faster aspart) versus insulin aspart (IAsp), both in combination with basal insulin degludec, in children and adolescents from Japan with type 1 diabetes (T1D). Of the onset 7 trial population (1 to <18 years; N = 777), 66 participants from Japan (65 Asian and one non-Asian) were randomized to mealtime faster aspart (n = 24), post-meal faster aspart (n = 19), or IAsp (n = 23). Data for the subgroup from Japan were analysed descriptively. Change from baseline in hemoglobin A1c 26 weeks after randomization was 0.23%, 0.74%, and 0.39%, for mealtime faster aspart, post-meal faster aspart, and IAsp respectively. Change from baseline in 1-h post-prandial glucose increment (based on 8-point self-measured blood glucose profiles) showed numerical differences in favor of mealtime faster aspart versus IAsp at breakfast (-30.70 vs. -2.88 mg/dL) and over all meals (-18.21 vs. -5.55 mg/dL). There were no clinically relevant numerical differences between treatment arms in the overall rate of severe or blood glucose-confirmed hypoglycemia. At week 26, mean total insulin dose was 1.119 U/kg/day for mealtime faster aspart, 1.049 U/kg/day for post-meal faster aspart, and 1.037 U/kg/day for IAsp. In conclusion, in children and adolescents with T1D from Japan, mealtime and post-meal faster aspart with insulin degludec was efficacious in controlling glycemia without additional safety concerns versus IAsp.

Achieving Glycaemic Control with Concentrated Insulin in Patients with Type 2 Diabetes

The recent introduction of the second-generation long-acting analogue insulins degludec and insulin glargine U300 have increased the choice of basal insulin therapy for patients with type 2 diabetes. The pharmacokinetic and pharmacodynamic properties of these insulins result in a flatter profile that lasts over 24 h and provides an increased window of administration of 6 h once daily. Large-scale multicentre randomised clinical trial programmes (BEGIN for degludec U100 and U200 and EDITION for glargine U300) evaluating these insulin therapies against glargine U100 have demonstrated that they are either non-inferior or superior for glycaemic efficacy and safety, but less likely to result in severe or nocturnal hypoglycaemia than glargine U100. The disposable pen devices for these insulins have been designed with patient satisfaction and convenience in mind. No concerns have arisen with adverse events with insulin analogues or cardiovascular safety from the ORIGIN and DEVOTE trials. As they demonstrate equivalent glycaemic efficacy to other basal insulins, they should be considered more in selected patient groups including those with recurrent or increased risk of hypoglycaemia, especially severe or nocturnal episodes, in the elderly or those living alone, and in patients with multiple co-morbidities such as cardiovascular or renal disease.

From venom peptides to a potential diabetes treatment

Cone snails have evolved a variety of insulin-like molecules that may help with the development of better treatments for diabetes.