Exubera was a brand of inhalable insulin from Pfizer, the first to gain FDA approval for treating both Type 1 and Type 2 diabetes. Launched in 2006, it offered an alternative to injections but was withdrawn from the market just over a year later. Its failure became a case study in pharmaceutical marketing and product design.
How Exubera Worked
Exubera’s system used single-use blisters of dry powder human insulin and a large mechanical inhaler. The insulin was created using recombinant DNA technology. Patients placed a 1 mg or 3 mg blister into the device and pumped a handle, which aerosolized the powder for inhalation.
The device, often compared in size to a flashlight or a small tennis ball can, delivered insulin particles deep into the lungs. Once inhaled, the powder dissolved on the surface of the pulmonary tissue. This allowed the insulin to be absorbed rapidly into the bloodstream, with absorption being independent of a patient’s body mass index.
The Market Failure of Exubera
Exubera’s withdrawal was a commercial decision driven by practical and financial factors, not a lack of effectiveness. A primary barrier was the inhaler itself. Its large, cumbersome size was inconvenient for patients to carry and conspicuous to use in public, earning it the nickname “the insulin bong” within the diabetes community.
High cost and dosing complexity added to its problems. Exubera was priced at a premium, costing around $5 per day compared to $2-$3 for injected insulin, leading many insurers to refuse reimbursement. Dosing was also confusing; a 1 mg blister was equivalent to about three units of injectable insulin, but a 3 mg blister equaled eight units, not the expected nine. This non-linear conversion made dose adjustments complicated for physicians and patients.
Physician and patient hesitancy was another hurdle. Doctors were cautious about prescribing a new delivery system with limited long-term data on pulmonary health. Patients were reluctant to adopt a technology that still required lung function tests and, for Type 1 diabetics, continued use of long-acting injectable insulin. These factors led to poor sales of just $12 million against a $2 billion forecast, prompting Pfizer to pull the product in 2007.
Clinical Performance and Side Effects
Clinically, Exubera was effective at controlling blood sugar. Its ability to lower HbA1c levels was comparable to short-acting injectable insulin. It also began to lower blood glucose within 10-20 minutes, a faster onset of action that was beneficial for managing post-meal glucose spikes.
The treatment did have side effects. A mild, non-progressive cough shortly after inhalation was the most common adverse effect, though it tended to diminish over time. Other less frequent side effects included dry mouth and throat irritation.
A mandatory safety protocol required all patients to undergo spirometry, a lung function test, before starting Exubera and at regular intervals. This monitored for any decline in pulmonary function, measured as FEV1. If a patient’s FEV1 declined by 20% or more from their baseline, treatment was discontinued, adding complexity and cost for patients and providers.
The Path Forward for Inhaled Insulin
The failure of Exubera did not end research into non-injectable insulin. The lessons learned from its shortcomings influenced the next generation of products. The experience highlighted the need for a more user-friendly device and simpler dosing, paving the way for further innovation.
Years after Exubera was discontinued, a new inhaled insulin, Afrezza, received FDA approval. Developed by MannKind Corporation, Afrezza addressed many of Exubera’s flaws. The Afrezza inhaler is much smaller and more discreet, easily fitting in the palm of a hand.
Its dosing is more straightforward, using cartridges labeled in familiar insulin units. While it shares some side effects like a mild cough, Afrezza’s improved design demonstrates an evolution in inhaled insulin technology. This progression shows how Exubera’s failure provided a roadmap for subsequent developments in diabetes treatment.