Dr. Jain: Absolutely. From the studies on inhaled insulin at ADA 2024, the key thing I found very interesting, regarding the pharmacokinetics of the insulin, was that it’s working very quickly. It starts working within minutes of administering it.
Additionally, it lasts in the body only for a shorter duration of time, compared with other injectable short-acting insulins, so it lasts in the body. The active insulin time is roughly about 2 hours or so, based on the studies, which in my mind opens up a whole world of possibilities because it means that people can take another correctional insulin if the blood sugars are still high after taking their first inhaled dose. You can take another dose subsequently without worrying about stacking of insulin.
Many of us are familiar with this term, which is if you take two shots of short-acting insulin too close to each other, the insulin doses might add up and there can be a big drop in the blood sugars; it’s called stacking of insulin. This can be potentially avoided.
Similarly, if you take your dinnertime inhaled insulin and the sugars are still high around bedtime, you could take a smaller dose of the inhaled insulin and not worry about middle-of-the-night hypoglycemia because the effect of the insulin would be only for a little while.
That’s one key learning that I found very helpful. The other important thing that I found was that this is not for everyone, so there are some restrictions. Essentially, the contraindication is that people who have asthma or COPD cannot be prescribed an inhaled insulin.
What are your thoughts, Dr. Kim, based on this for your practice in primary care?
Dr. Kim: It is very fascinating, for sure. I cannot wait to get hold of this insulin. I can already think of some patients who may benefit. You’ve mentioned the asthma and COPD patients, and that makes more sense because there is an actual airway problem.
I also wonder what will happen to patients who have restrictive airway disease, where asthma and COPD fall under obstructive airway disease. What if they have obesity, where it’s really pressing into the diaphragm, and where they may not be able to take the deep breath in? How will they react?
What about someone who’s got a cold, someone who has postnasal drip, or someone who tends to cough frequently? What about egg allergies? There are many question marks around this insulin before initiating these medications. There is excitement, but there are also many questions at the same time.
Dr. Jain: I think these are very important, practical considerations that we’ll uncover as we start using more of this in clinical practice. The other important thing to note is that the presenters told us it’s important to monitor pulmonary function tests. It’s important to get a baseline pulmonary function test, and then we have to do another one in 6 months, followed by annually thereafter.
If, at any point of time, the FEV1 drops by 20% or more, then that would be an indication for discontinuation of the inhaled insulin. The pulmonary function test does not need to be one of those fancier ones. The study group would just do office spirometries. I’m wondering, Dr. Kim, in primary care, do you think this could potentially be a rate-limiting factor?