“Diabetes”, the word by itself raises an alarm, fear and tension not only for those who suffer from it but also for healthy
individuals. It’s a condition of the body that results due to the lack of production of insulin by the beta cells of Islets of langerhans of pancreas. This results in increased glucose concentration in blood and urine and also poses various adverse effects like fatigue, susceptibility to infections, prolonged time for wound healing etc. The cure for this disorder is to supplement the body with insulin from external sources like Insulin injections. It’s been quite a long time every diabetic individual has been praying for an alternative. A diabetic patient is advised to take insulin injection before his meals. The prayers have been answered. The gift is the emergence of Inhalable insulin known as Exubera, developed by Nektar Therapeutics that should be hitting the market in near future.
Nektar's dry powder formulation of inhaled insulin, if
approved, would be the first protein therapeutic delivered through the lungs. Inhaled insulin would provide a more convenient, less painful dose for the 9.5 million Americans who take mealtime insulin and represents a potential $4.6 billion worldwide market, according to estimates from investment bank SG Cowen in Boston. The two most important concerns in the early years of development were reproducibility of dosing and adverse
pulmonary effects.
Careful inhaler system engineering and long-term phase 3 studies have helped solve such issues. By comparison, effective and reproducible dosing has always been a problem even for asthma inhalers, but asthma drugs can be delivered over a wide range of concentrations and still be effective locally. On the other hand Insulin, a protein enzyme, has a much narrower therapeutic range and needs to get into the systemic blood circulation through the alveoli, or thin-membraned sacs, in the deep lung.
The biggest remaining question, however, is whether there will be longer-term pulmonary effects from chronic use throughout a lifetime. Exubera which is the most advanced inhaled product in Nektar's pipeline is currently being retested in phase 3 clinical trials after an initial long-term phase 3 study failed to meet regulatory standards. The study released last month shows that patients taking Exubera with an oral glycemic control agent had a slight decrease in lung function after six months. But by the end of two years, the patients' pulmonary function was the same as that of the control patients who took only oral agents. Developers are hopeful that an approved inhaled insulin product would increase not only patient convenience, but also compliance, and lower the numbers of diabetics with poorly controlled blood glucose-the major cause of disease symptoms and complications.
If Exubera is approved, it would also open the way for other inhaled protein therapeutics that now require injections namely hormones for fertility or treating deficiencies and immune system modulating proteins.