Exubera is a very rapid acting insulin developed and licensed for delivery by inhalation. It has been formulated as a dry powder for use with a specifically designed pocket-sized inhaler device that allows diabetic patients to see the dose delivered.
The dose is taken by inserting a blister containing the powdered insulin into the inhaler device. The handle is then pumped and a button used to release the dose into the clear inhaler chamber. Breathing normally through the mouth, the patient inhales the insulin, delivering it to the lungs where it is rapidly and efficiently absorbed into the blood stream prior to eating.
In healthy volunteers, inhaled administration of insulin produced a faster onset of glucose lowering activity (10-20 minutes) than subcutaneously administered fast-acting soluble human insulin, with the maximum effect exerted approximately two hours post-dose. The duration of action was around six hours, which was comparable to the duration of glucose lowering activity of subcutaneous fast-acting human insulin and greater than that seen with fast-acting insulin analogues.
In clinical trials of patients with type I diabetes, those given inhaled insulin in combination with long-acting or intermediate-acting insulin had similar reductions in HbA1c compared with those given subcutaneous insulin alone and the percentage of those who achieved a goal of HbA1c <7.0% was comparable between groups. Moreover, fasting plasma glucose levels were significantly lower in patients treated with regimens including inhaled insulin than in patients given subcutaneous fast-acting insulin alone.
In patients with type II diabetes, inhaled insulin in combination with long-acting or intermediate-acting insulin produced similar changes in HbA1c compared with those treated with subcutaneous insulin alone and fasting plasma glucose levels were significantly lower in those given inhaled insulin regimens.
In clinical trials of patients not adequately controlled with oral agents, inhaled insulin with or without oral therapy produced greater improvements in HbA1c than oral agents alone. In most studies, the percentage of patients achieving HbA1c <7.0% was higher for patients treated with a regimen including inhaled insulin than for those treated with oral agents alone. Fasting plasma glucose levels were similar to or lower in patients using inhaled insulin regimens compared with oral therapy alone. However, in patients with type II diabetes adequately controlled using oral agents, inhaled insulin did not further improve glycaemic control.
Most of the side effects observed during clinical trials were mild to moderate in nature. However, a small but consistent group difference was observed in pulmonary function i.e. FEV1 decline. In studies of up to two years duration there was no accelerated decline in FEV1 beyond three to six months and on discontinuation the differences resolved within six weeks.
Inhaled insulin is not suitable for use in children or in adults with congestive heart failure, smokers, unstable or severe asthma or COPD and it should be discontinued if FEV1 falls by more than 20% from baseline.
Indications: Type II diabetes not adequately controlled by oral antidiabetic agents. Type I diabetes in conjunction with long or intermediate acting subcutaneous insulin.
Adult Dose: By inhalation with the insulin inhaler within 10 minutes of the start of a meal. Dosage according to individual requirements. Onset within 10 to 20 minutes, duration approximately six hours.
1mg and 3mg unit doses are not interchangeable. Replace inhaler annually and insulin release units every two weeks.
Child Dose: Under 18 years, not recommended.
Contraindications: Congestive heart failure, smokers, poorly controlled, unstable or severe asthma, COPD.
Special Precautions: Intercurrent respiratory infections, hepatic or renal impairment, low body-weight. Perform spirometry before and during therapy; discontinue if decline in FEV1 >20%.
Adverse Effects: Cough, dyspnoea, cough, throat irritation.
? Report any adverse reaction to CHM.
Further information: Pfizer Ltd, Walton Oaks, Dorking Road, Tadworth, Surrey KT20 7NS. Tel: (01304) 616161.