Exubera became the first inhaled peptide drug approved for clinical use in 2006, showing that insulin could be effectively delivered through the lungs as an alternative to injections.
First inhaled peptide drug approvedExubera proved in 2006 that a peptide hormone could be delivered through the lungs with efficacy comparable to injection
What the researchers found
Exubera was approved in 2006 as the first inhaled insulin and the first peptide hormone successfully delivered via the pulmonary route for clinical use. Clinical trials demonstrated that it was effective at controlling blood glucose, apparently safe, and preferred by patients compared to subcutaneous mealtime insulin injections.
The review highlights that the lungs' rich vascularity, large surface area, and immunotolerant characteristics make them an ideal target for peptide delivery, overcoming the traditional barrier of poor bioavailability that had limited inhaled peptide drugs. The authors noted that Exubera could reduce injection burden for both type 1 and type 2 diabetes patients and encourage earlier insulin initiation.
Why it matters
Exubera was a watershed moment in peptide drug delivery. For the first time, it was proven that a peptide hormone — a molecule normally destroyed by the body before reaching the bloodstream — could be delivered effectively through the lungs. While Exubera itself was commercially unsuccessful (withdrawn in 2007), it paved the way for subsequent inhaled insulin products (like Afrezza) and demonstrated the broader principle that the lungs are a viable delivery route for peptide therapeutics. The lessons from Exubera continue to influence peptide drug delivery research today.
The numbers in context
First inhaled insulin approved for clinical use · Effective for type 1 and type 2 diabetes · Preferred by patients over subcutaneous injection · Approved 2006
How the study worked
This is a narrative review published at the time of Exubera's regulatory approval. It synthesizes clinical trial data on inhaled insulin's efficacy, safety, and patient preference, along with the pharmacological and physiological principles that make pulmonary delivery of peptides feasible.
Who was studied
Review covering clinical trial participants with type 1 and type 2 diabetes
What this study cannot tell us
This review was written at the time of Exubera's approval in 2006, reflecting the optimism of that moment. It does not account for the product's subsequent commercial failure and withdrawal in 2007, safety signals regarding reduced lung function that emerged with longer-term use, or the practical challenges (bulky inhaler device, dosing complexity, cost) that limited patient adoption. The review presents clinical trial data without post-marketing experience.
How to read the evidence
Rated 'moderate' because this review summarizes clinical trial data showing efficacy and safety, but it's a narrative review written at time of approval without post-marketing data. Subsequent real-world experience revealed limitations not captured here.
When this study was published
Published in 2006 in Diabetes & Vascular Disease Research. This is a historical document — Exubera was withdrawn from the market in 2007 due to poor sales. A newer inhaled insulin (Afrezza) was approved in 2014. The review remains valuable as a record of the scientific case for pulmonary peptide delivery.
The bigger picture
Exubera sits in peptide history as a technically successful but commercially failed product — a cautionary tale about the gap between scientific achievement and market adoption. The device was bulky, dosing was complex, and cost was high, leading to its withdrawal just one year after launch. But the science was sound: pulmonary delivery of peptides works. Afrezza (a later inhaled insulin with a smaller device) built on Exubera's proof-of-concept, and researchers continue exploring inhaled delivery for other peptides and biologics. Exubera's legacy is the validation of a delivery platform, not a failed product.
Questions still open
- Why did Exubera fail commercially despite positive clinical trial results and patient preference data?
- What lung safety concerns emerged with inhaled insulin, and how have later products like Afrezza addressed them?
- Can the pulmonary delivery platform validated by Exubera be applied to other therapeutic peptides beyond insulin?
Common questions
Why was Exubera taken off the market if it worked?
Is there still an inhaled insulin available?
Read the original research
Inhaled insulin (Exubera): Combining efficacy and convenience.
Diabetes & vascular disease research, 3(3), 179-85
Citation
Bellary, Srikanth; Barnett, Anthony H. (2006). Inhaled insulin (Exubera): Combining efficacy and convenience.. Diabetes & vascular disease research, 3(3), 179-85.