Insulin Therapy. In the history of medical advancements, few discoveries have made as remarkable an impact on the lives of diabetes patients as the discovery of insulin and its development into a synthetic hormone for diabetes care. From its early days as a crude extract to the refined analogs available today, the journey of insulin stands as a testament to the pursuit of improved patient care.

Let us explore the transformative trajectory of insulin therapy – from the early days of regular injections to the intricate production of modern analogs like Lantus and beyond.

The introduction of the first insulin therapy

The discovery of insulin in 1921 marked a monumental breakthrough in medical history, transforming the prognosis for people diagnosed with diabetes. Before this landmark moment, a diagnosis of diabetes was akin to a life sentence with few chances of survival. However, through the collaborative efforts of brilliant minds like Frederick Banting, Charles Best, and their colleagues, insulin was successfully isolated from the animal pancreas, offering a glimmer of hope to countless individuals worldwide.

January 11, 1922, 14-year-old Leonard Thompson became the first person to receive an insulin injection as a treatment for diabetes. However, Leonard’s first dose had an apparent impurity, which caused an allergic reaction. Despite this initial setback, the discovery of insulin and its use in patients like Leonard marked a historic breakthrough in diabetes treatment.

As mentioned earlier, the initial insulin formulations were relatively crude, with regular insulin being the first type developed for medical use. Also known as short-acting insulin, it begins working within 30 minutes, reaches its peak effectiveness in approximately 2-3 hours, and lasts 4-6 hours. Manufacturers sourced regular insulin from animals, particularly porcine and bovine pancreas. While it represented a significant advancement in that period, its use required multiple daily injections.

Insulin formulation and administration advancements have since evolved, providing people with diabetes more convenient and effective treatment options.

More advancements in insulin action

NPH (Neutral Protamine Hagedorn)

NPH (Neutral Protamine Hagedorn) is a notable advancement in insulin formulation as our understanding of its role deepened. Researchers aimed to refine insulin’s formulations to provide more consistent and extended effects, leading to the introduction of NPH insulin.

NPH (Neutral Protamine Hagedorn) insulin extends the duration of insulin action. It comprises regular insulin combined with protamine, a protein that slows down its absorption and prolongs its effect. Typically, NPH insulin works within 1-2 hours, reaches its peak effectiveness in about 4-8 hours, and lasts up to 12-18 hours.

George Simmons has had type 2 diabetes for over 40 years. He shared his journey of managing diabetes with NPH in an article published on Diabetes.co.uk. At one point, George began using NPH insulin to help achieve better glucose control throughout the day. He described how NPH insulin provided reliable basal insulin coverage, allowing him to manage his blood sugar levels effectively.

Ultra-Lente Insulin

The evolution of insulin therapy saw further progress with the development of Ultra-Lente insulin. This long-acting insulin had a prolonged duration of action, lasting up to 20-30 hours. It aimed to mimic the basal insulin secretion of a healthy pancreas, reducing the need for multiple injections and offering a more consistent glycemic profile. However, Ultra-Lente insulin still had its limitations. 

According to experts, Ultra-Lente insulin may have a slower onset of action, so it may take longer to observe its effects. It could also increase the risk of hypoglycemia (low blood sugar) because of its prolonged action and potential for delayed onset. Studies also found that because of its longer duration of action, Ultra-Lente insulin may have less flexibility in adjusting insulin doses or titration. As a result, researchers continued to strive for more refined solutions.

The era of analog insulins

Analog insulins have revolutionized insulin therapy by offering more predictable and tailored action profiles. These insulins are engineered with specific modifications in their molecular structure that enhance control over blood sugar levels. 

Lantus, one of the pioneering analog insulins, offers a steady insulin release for 24 hours. This prolonged effect minimizes the risk of blood sugar fluctuations and allows for improved glycemic control. Lantus has become widely used because of its convenience, as it typically requires only one injection per day.

Levemir was another analog insulin. It further advanced insulin therapy options by offering a variable action profile. It provides basal insulin coverage for up to 24 hours, allowing individuals to adjust dosing according to their needs. This flexibility contributes to improved glycemic control and better customization of insulin therapy.

The development and availability of these analog insulins represented a significant stride forward in diabetes management. They offer individuals with diabetes greater precision, control, and flexibility in managing their blood sugar levels. By providing more predictable action profiles, these analog insulins have played a crucial role in enhancing the quality of life for many individuals with diabetes.

Beyond Lantus

The field of insulin therapy continued to evolve even after the introduction of Lantus and Levemir, with the emergence of more advanced insulin analogs in subsequent years. One notable addition was Tresiba (Degludec), an ultra-long-acting insulin that pushed the boundaries of basal insulin coverage to new levels. Tresiba boasts an exceptional duration of action, exceeding 42 hours, which allows for unparalleled flexibility in dosing intervals while minimizing the risk of hypoglycemia.

The continuous progress in insulin therapy is a testament to the tireless support and research within the medical community. From the days of uncertain injections to the precise analog formulations and innovative delivery systems available today, the landscape of diabetes management has undergone profound changes. These advancements in insulin therapy have not only translated into an enhanced quality of life for individuals with diabetes but have also contributed to a reduced risk of complications and increased empowerment in diabetes self-management