Exubera™ is a drug that was marketed by the Pfizer corporation for just over a year in the mid-1990s. It was a form of insulin that could be inhaled, rather than injected, as part of a person's treatment of diabetes. It could be used for patients with either Type I or Type II diabetes. It was withdrawn from the market in the United States because of lack of popular interest in the drug, as well as its lackluster sales figures. There were no safety concerns cited by the manufacturer as part of the withdrawal.
While it was available, the drug consisted of a powdered form of human insulin that was inhaled into the lungs, where it would be absorbed. Insulin generally works over just the next few hours when it is taken in this way. Because of this, inhaling Exubera™ did not eliminate the need to inject insulin that was longer lasting. Had it done so, the drug likely would have been more popular as an alternative to repeated injections.
The main advantage offered by Exubera™ was that it acted more swiftly than injected insulin. Despite this fact, it was never widely accepted by diabetes patients and their physicians. This was not the only kind of inhaled insulin available at the time, but most of the other related drugs were withdrawn from the market shortly after Exubera™.
Some mild side effects were associated with the use of Exubera™ in clinical trials, with low blood sugar being the most common. This is usually easily treated either by glucose tablets or a piece of hard candy, which patients were recommended to keep with them as a precaution against this condition. Other side effects that were observed included cough, sore throat, ear pain, dry mouth and runny nose.
At the time of the withdrawal, Exubera™ was not believed to have any link to increased risk for lung cancer or any similar disease. Pfizer did release a statement six months later to the effect that some correlation of this kind may have been found, however. Of about 4,700 patients who were treated with Exubera™ in clinical trials, six had developed lung cancer by the time the letter was released. This was compared to one patient getting lung cancer out of 4,300 who were given a placebo. Further research in the years to follow indicated that these six had a prior history of cigarette smoking, and that this is what likely made them more susceptible to lung cancer.