Drug manufacturer Pfizer has changed the labeling on its inhaled insulin, Exubera, to warn that a few cases of lung cancer have occurred in people who have used the product. Although Pfizer announced that it would stop marketing Exubera last year (see "Exubera Inhaled Insulin Discontinued"), it is still available by prescription and is being used by about 4,000 people worldwide.
Data from a clinical trial program for Exubera showed that 6 out of 4,740 people taking Exubera developed lung cancer compared to 1 out of 4,292 people not taking Exubera. One Exubera user who was not part of a clinical trial also reported developing lung cancer. The updated labeling states that all of these people had a prior history of cigarette smoking and that there were not enough cases to determine whether the use of Exubera was related to the development of lung cancer.
In a statement released by Pfizer, Joe Fezcko, M.D., (the company’s Chief Medical Officer) stated that “Physicians should seek alternate treatment options to maintain patients’ glycemic control.” However, in a letter to people taking Exubera as part of an “extended transition program,” Rochelle L. Chaiken, M.D., (Vice President of Global Medical Cardiovascular and Metabolic Disease at Pfizer) advised people not to stop taking Exubera without discussing it with their doctor first.
Pfizer announced that it would cease marketing Exubera in October of 2007, citing poor sales as the reason. Nektar Therapeutics, the company that originally developed Exubera and partnered with Pfizer to market it, announced this month that it was ending its search for a new marketing partner and was moving its business away from inhaled insulin.
Two other pharmaceutical companies that had been developing their own inhaled insulin products have also recently ceased pursuing them: Novo Nordisk and partner Aradigm ended development on their AERx system in January of this year, and Eli Lilly & Co. and partner Alkermes, Inc. dropped their AIR Insulin project in March. A smaller company called MannKind Corp. is continuing to develop its Technosphere Insulin product; data from phase 3 clinical trials (the final round of trials before a new drug is submitted to the FDA for approval) of this product should become available later this year.