Self-mixed/split insulin regimen: a serious omission in the ADA/EASD position statement

Evolution of biosynthetic human insulin and its analogues for diabetes management

Hormones play a crucial role in maintaining the normal human physiology. By acting as chemical messengers that facilitate the communication between different organs, tissues and cells of the body hormones assist in responding appropriately to external and internal stimuli that trigger growth, development and metabolic activities of the body. Any abnormalities in the hormonal composition and balance can lead to devastating health consequences. Hormones have been important therapeutic agents since the early 20th century, when it was realized that their exogenous supply could serve as a functional substitution for those hormones which are not produced enough or are completely lacking, endogenously. Insulin, the pivotal anabolic hormone in the body, was used for the treatment of diabetes mellitus, a metabolic disorder due to the absence or intolerance towards insulin, since 1921 and is the trailblazer in hormone therapeutics. At present the largest market share for therapeutic hormones is held by insulin. Many other hormones were introduced into clinical practice following the success with insulin. However, for the six decades following the introduction the first therapeutic hormone, there was no reliable method for producing human hormones. The most common source for hormones were animals, although semisynthetic and synthetic hormones were also developed. However, none of these were optimal because of their allergenicity, immunogenicity, lack of consistency in purity and most importantly, scalability. The advent of recombinant DNA technology was a game changer for hormone therapeutics. This revolutionary molecular biology tool made it possible to synthesize human hormones in microbial cell factories. The approach allowed for the synthesis of highly pure hormones which were structurally and biochemically identical to the human hormones. Further, the fermentation techniques utilized to produce recombinant hormones were highly scalable. Moreover, by employing tools such as site directed mutagenesis along with recombinant DNA technology, it became possible to amend the molecular structure of the hormones to achieve better efficacy and mimic the exact physiology of the endogenous hormone. The first recombinant hormone to be deployed in clinical practice was insulin. It was called biosynthetic human insulin to reflect the biological route of production. Subsequently, the biochemistry of recombinant insulin was modified using the possibilities of recombinant DNA technology and genetic engineering to produce analogues that better mimic physiological insulin. These analogues were tailored to exhibit pharmacokinetic and pharmacodynamic properties of the prandial and basal human insulins to achieve better glycemic control. The present chapter explores the principles of genetic engineering applied to therapeutic hormones by reviewing the evolution of therapeutic insulin and its analogues. It also focuses on how recombinant analogues account for the better management of diabetes mellitus.

Prandial Insulins: A Person-Centered Choice

PURPOSE OF REVIEW

Postprandial hyperglycemia, or elevated blood glucose after meals, is associated with the development and progression of various diabetes-related complications. Prandial insulins are designed to replicate the natural insulin release after meals and are highly effective in managing post-meal glucose spikes. Currently, different types of prandial insulins are available such as human regular insulin, rapid-acting analogs, ultra-rapid-acting analogs, and inhaled insulins. Knowledge about diverse landscape of prandial insulin will optimize glycemic management.

RECENT FINDINGS

Human regular insulin, identical to insulin produced by the human pancreas, has a slower onset and extended duration, potentially leading to post-meal hyperglycemia and later hypoglycemia. In contrast, rapid-acting analogs, such as lispro, aspart, and glulisine, are new insulin types with amino acid modifications that enhance their subcutaneous absorption, resulting in a faster onset and shorter action duration. Ultra-rapid analogs, like faster aspart and ultra-rapid lispro, offer even shorter onset of action, providing better meal-time flexibility. The Technosphere insulin offers an inhaled route for prandial insulin delivery. The prandial insulins can be incorporated into basal-bolus, basal plus, or prandial-only regimens or delivered through insulin pumps. Human regular insulin, aspart, lispro, and faster aspart are recommended for management of hyperglycemia during pregnancy. Ongoing research is focused on refining prandial insulin replacement and exploring newer delivery methods. The article provides a comprehensive overview of various prandial insulin options and their clinical applications in the management of diabetes.

Forum for Injection Technique and Therapy Expert Recommendations, India: The Indian Recommendations for Best Practice in Insulin Injection Technique, 2017

Health-care professionals in India frequently manage injection or infusion therapies in persons with diabetes (PWD). Patients taking insulin should know the importance of proper needle size, correct injection process, complication avoidance, and all other aspects of injection technique from the first visit onward. To assist health-care practitioners in their clinical practice, Forum for Injection Technique and Therapy Expert Recommendations, India, has updated the practical advice and made it more comprehensive evidence-based best practice information. Adherence to these updated recommendations, learning, and translating them into clinical practice should lead to effective therapies, improved outcomes, and lower costs for PWD.

The development of new basal insulins: is there any clinical advantage with their use in type 2 diabetes?

INTRODUCTION

The basal insulin products currently on market do not optimally mimic endogenous insulin secretion. These unmet clinical needs have fueled the development of new basal insulin analogues for improving their pharmacokinetics/pharmacodynamics profile.

AREAS COVERED

We review the recent literature investigating the efficacy and safety of new basal insulin analogues in type 2 diabetes, as in the USA, insulin utilization accounted for 26% of treatment visits for these patients in 2012. Insulin degludec is a desB30 insulin acylated at the LysB29 residue with a glutamate linker and 16-carbon fatty diacyl side chain. Insulin lispro has been PEGylated at lysine B28, via a urethane bond, which increases the hydrodynamic size of the molecule and reduces its absorption and clearance following subcutaneous administration. Glargine U300 represents a new high-strength glargine formulation (300 U/ml): once injected, U300 forms a compact subcutaneous depot with a smaller surface area to produce a more gradual and prolonged release. Both PEG-lispro and glargine U300 are not yet on the market.

EXPERT OPINION

Ultra-long acting and high-strength formulations of new basal analogues have the potential for less glycemic variability, less (nocturnal) hypoglycemia and weight-loss advantage for PEG-lispro. However, these new basal insulin analogues need to be monitored closely for adverse signals.