FDA approves updated label with new dosing guidance for inhaled insulin

Technosphere insulin was approved by the FDA in 2014, yet its uptake has been extremely slow. One recent survey using Epic Cosmos noted that between Jan. 1, 2015, and Oct. 8, 2024 with at least two prescriptions over a 365-day period, only 647 individuals met the criteria for using the therapy (Burstain TL, et al. Diabetes Technol Ther. 2026;doi:10.1177/15209156251412816). While this database doesn’t include all Americans, it currently captures 300 million people.
Why the poor uptake? This insulin is much quicker than standard rapid-acting insulin analogs and reduces postprandial hyperglycemic burden. Many find this desirable. Certainly, the explosion of automated insulin delivery over the past 5 years could have resulted in less usage, yet many of us treat patients with both therapies.
One challenge since technosphere insulin’s launch has been the unit conversion. The insulin currently comes in three doses: 4U, 8U and 12U cartridges. It became very clear to many of us years ago that a 4U cartridge of technosphere insulin was not the same as 4U of insulin aspart or lispro. One needed more technosphere insulin compared to the standard rapid-acting analogs. Unfortunately, many patients and clinicians did not appreciate that, partly because this was not noted on the label. Many excited to use technosphere insulin stopped because “it didn’t work.” It wasn’t until larger studies were published that we had a better understanding about the potency of technosphere insulin.
In adults, it was found that the conversion of technosphere insulin to rapid-acting analogue was greater than 2:1 (Hirsch IB, et al. Diabetes Care. 2024;doi:10.2337/dc24-0838). For youths, the conversion is closer to 3:1 (Haller MJ, et al. Diabetes Care. 2025;doi:10.2337/dc25-1994). The amount of insulin powder in the cartridge is not equivalent to what is absorbed in the lungs. Thus, the 1:1 conversion on the original 2014 label was wrong.
The good news is that the FDA changed the label to be consistent with the published data. Specifically, the starting dose of technosphere insulin should be twice the usual dose of rapid-acting analog. Should the converted dose of technosphere insulin not be in a multiple of four (the lowest-dose cartridge), then one would round down. For example, for 5U of the rapid-acting analogue, one would take 8U of technosphere insulin as one can’t take 10U.
As the studies have shown that we have been dosing this insulin incorrectly for over a decade, it is quite possible the frustration will be minimized, and more insulin-requiring patients will find this insulin beneficial.