Pfizer said this morning that it’s adding a warning about lung cancer to the labeling for its inhaled insulin Exubera. The number of cases is low — six out of 4,740 patients treated with the drug, compared with one case out of 4,292 comparable patients who did not receive the drug. (see "Lung Cancer Warning May Be Last Gasp for Inhaled Insulin").Of course, Pfizer says that "all patients who developed lung cancer had a prior history of cigarette smoking, and that there were too few cases to determine whether the development of lung cancer is related to the use of Exubera" (see Pfizer's statement).
But assuming the 4,292 "comparable" patients in the control group also have the same number of smokers, I'd be pretty scared right now if I were using Exubera and smoking. Probably scared enough to quit the study and stop using Exubera -- but not quite scared enough to quit smoking!
Exubera failed miserably not because physicians or patients thought it could cause lung cancer, but because it did not live up to the hype of marketers -- who only were able to get a few DTC commercials going on TV and stories written in the press about Exubera before it was pulled from the market by Pfizer. You can read more about the failure here: "Exubera: A Titanic Failure! What the survivors are saying."
But imagine a world where Exubera was still on the market and this bit of news comes out. Would Pfizer caution diabetic smokers to quit smoking -- using Chantix, of course -- before bonging away on Exubera? I think it could have happened! Which is why I say thank God that it was such a lame device that both doctors and patients were not impressed!
More conjecture: What did Pfizer know about this "side effect" of Exubera BEFORE it decided to pull it form the market? Any hint whatsoever that increased chance of lung cancer could be a side effect might have been the determining factor for pulling Exubera off the market. If true, I suppose Pfizer would have said so and gained some credibility. Who knows?