MannKind Corporation was giddy to announce that it has finally received FDA approval for its inhaled, fast-acting insulin. And what insulin-dependent diabetic wouldn't applaud that news? No more needles, just a quick puff and the medicine is safely delivered.
Well, when it comes to big profits, big companies, and the FDA, one typically doesn't have to look too far to find the rub.
The new drug, called AFREZZA, has cost MannKind Corporation about $80 million so far to develop. To its credit, the first string of attempts at FDA approval were rejected, pending longer term studies that would demonstrate it was safe. With the completion of clinical trials - the longest being 24 weeks - the FDA was apparently satisfied.
So why the concern?
I'll try to keep this quick. First, insulin raises the level of a chemical called TGF-beta1. This chemical, produced by immune cells of the body, will lead to fibrosis if chronically elevated. In other words, raising TGF-beta1 levels in the lungs would be expected to be associated with lung fibrosis. For the gory, geeky details, read them here.
Perhaps of even greater concern, TGF-beta1 is strongly associated with lung cancer, and especially with stimulating its growth once present. Again, the details can be read here. So, does this new inhaled insulin increase the risk of lung fibrosis or even lung cancer? We can't know, because it is impossible to figure these things out with a study that lasts 24 weeks. It is interesting to note that the most common reported side effects experienced by those in the trials were chronic cough and throat pain.
It would be great for diabetics needing insulin to have options other than injections. But delivering insulin to the lung tissue has the potential to create lung fibrosis, respiratory disease and even more serious problems The last thing diabetics need is more health issues to deal with. Until longer studies are done to find the impact of exposing the lung tissue to insulin (which does not typically get exposed to insulin), insulin-dependent diabetics would be wise to stick with their injections.
At Immersion Health, we continue to implement the low-carb ketogenic diet with our diabetic patients. Why? Because there is strong evidence that it works! The best way to avoid injected insulin is not to need it in the first place.