Inhaled insulin: A model for pulmonary systemic absorption?

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.

A Review of the Impact of Smoking on Inhaled Insulin: Would You Stop Smoking if Insulin Can Be Inhaled?

High prevalence of diabetes and the need for tight glycemic control have been well established. With the invention of inhaled insulin, an alternate route has been explored and shows great promise. Inhaled insulin shows a similar physiologic response to subcutaneous insulin, with a faster onset of action, making it suitable for post-prandial hyperglycemia. This comes as a great relief, especially to those who are hesitant to use multiple injections in a day. Many factors affect insulin absorption, including device, particle size, airway patency. Another essential factor is smoking, which is prevalent among people with diabetes, as is in the non-diabetic population. Smoking increases the absorption of inhaled insulin, but it is not a straight fact, since acute smoking, passive smoking, chronic smoking - all have different effects on inhaled insulin. Furthermore, inhaled insulin is also affected by lung diseases. Most studies that have been conducted have included limited populations, thus questioning their generalisability. The studies from inception till 2020 have shown increased permeability of epithelial with acute smoking, change of epithelial layer back to normal after few weeks of smoking cessation, and reverting to chronic smoker levels with just one to two days of start in smoking. Data also suggests that smoking causes a reduction in insulin sensitivity, which could compensate for its increased absorption. Nicotine causes a decrease in the absorption of subcutaneous insulin, but its effect has not been seen on inhaled insulin. More studies, including diabetic smoker patients, need to be performed to give a specific set of variables. This would also add another reason to encourage smokers to quit smoking.

Vibrating Mesh Nebulisers – Can Greater Drug Delivery to the Airways and Lungs Improve Respiratory Outcomes?

Aerosols are an increasingly important mode of delivery of drugs, particularly bronchodilators, for the treatment of respiratory diseases, notably asthma and chronic obstructive pulmonary disease. The most common type of nebuliser is the jet nebuliser (JN); they have been in use for more than a century but these devices can be cumbersome to use and may sometimes deliver insufficient amounts of drug. A more recent development in aerosol therapy is the vibrating mesh nebuliser (VMN) which is very user friendly and is more efficient than the JNs due to an extremely low residual volume. Scintigraphy images from studies of volunteer subjects using radio-labelled aerosol treatment show that VMN-generated aerosols deliver more drug to patients in a shorter period of time than JN-generated aerosols. Various bench, animal model and small clinical studies have shown that VMNs are more efficient than JNs in drug delivery, potentially improving clinical outcomes. These studies have included various breathing circuits used in mechanical ventilation (MV), non-invasive ventilation, high-flow nasal cannula systems and devices for spontaneously breathing patients. The efficiency of drug delivery was affected by factors including the position of the nebuliser in the circuit and humidity. Some studies have shown potential substantial savings by hospitals in the cost of MV treatments after switching from metered dose inhalers to VMNs. VMNs have also been shown to be effective for the administration of inhaled antibiotics, corticosteroids and other drugs. Larger studies of the effects of VMNs on patient outcomes are needed but they are likely to be an increasingly important means of administering therapies to a burgeoning population with respiratory disease.

Future prospect of insulin inhalation for diabetic patients: The case of Afrezza versus Exubera

The current review was designed to compare between the insulin inhalation systems Exubera and Afrezza and to investigate the reasons why Exubera was unsuccessful, when Afrezza maker is expecting their product to be felicitous. In January 2006, Pfizer secured FDA and EC approval for the first of its kind, regular insulin through Exubera inhaler device for the management of types 1 and 2 diabetes mellitus (DM) in adults. The product was no longer available to the market after less than two years from its approval triggering a setback for competitive new inhalable insulins that were already in various clinical development phases. In contrary, MannKind Corporation started developing its ultra-rapid-acting insulin Afrezza in a bold bid, probably by managing the issues in which Exubera was not successful. Afrezza has been marketed since February, 2015 by Sanofi after getting FDA approval in June 2014. The results from this systematic review indicate the effectiveness of insulin inhalation products, particularly for patients initiating insulin therapy. Pharmaceutical companies should capitalize on the information available from insulin inhalation to produce competitive products that are able to match the bioavailability of subcutaneous (SC) insulin injection and to deal with the single insulin unit increments and basal insulin requirements in some diabetic patients or extending the horizon to inhalable drug products with completely different drug entities for other indications.

New technologies for diabetes: a review of the present and the future

This review summarizes the technologies in use and in the pipeline for the management of diabetes. The review focuses on glucose meters, continuous glucose monitoring devices, insulin pumps, and getting clinicians connected to technologies. All information presented can be found in the public domain, and was obtained from journal articles, websites, product review tables in patient publications, and professional conferences. The technology concerns, ongoing development and future trends in this area are also discussed.