How would you feel about inhaling, rather than injecting, your daily dose of insulin?

If you take insulin for type 1 or type 2 diabetes, a new form of insulin—inhalable insulin—has just been approved by the US Food and Drug Administration (FDA). Inhalable Afrezza is a rapid-acting insulin, meaning it takes effect within approximately 15 minutes, is at its peak in about an hour, and will be effective for between two and four hours. Afrezza is taken before or around mealtime.

The FDA approval follows the recommendation of the agency’s Endocrinologic and Metabolic Drugs Advisory Committee, which voted 13 to 1 that Afrezza met FDA safety and efficacy standards for type 1 diabetes treatment in April 2014. They also voted unanimously that Afrezza was a viable way to treat type 2 diabetes.

Possible Problems

But Afrezza may not be a big commercial success, thanks to several problems with the inhalable insulin, experts say: For one thing, only about 10% of the insulin you inhale actually gets absorbed into your system and works, says Joel Zonszein, MD, director of the Clinical Diabetes Center at Montefiore Medical Center in New York City; it’s not the most efficient way to get insulin.

Furthermore, the inhalable insulin isn’t the type needed by the majority of individuals with type 2 diabetes: "This inhalable insulin is rapid acting, not basal [intermediate- and longer-acting] insulin," Zonszein points out. "So a person who takes basal insulin as well as rapid acting insulin would still need to inject the basal insulin."

Perhaps the biggest drawback, though, is the possible link between the inhalable insulin and cancer: In clinical trials, lung cancer was more common among individuals who took Afrezza, although the research was far from conclusive. "The insulin may activate receptors [cells that receive or respond to changes in the body] that can cause malignancy [cancerous tumors]," Zonszein says. "There is no concrete evidence that this is what happens, but the concern remains." Individuals who smoke, or who have a cold, should not be prescribed Afrezza.

Afrezza needs further testing to make sure it has no adverse effects on the lungs, says Spyros Mezitis, MD, PhD, of Lenox Hill Hospital in New York City. And "How well it works depends on how good the person’s lungs are," he says.

The Past—and Future—of Inhalable Insulin

Afrezza was developed by the Valencia, CA-based MannKind Corporation, which twice before failed to win FDA approval for the product. Afrezza isn’t the first inhalable insulin to be developed; back in 2006, Pfizer won approval for an inhaled insulin known as Exubera. The product was not a success and was subsequently taken off the market. Afrezza differs from Exubera in that it’s a much smaller—and easier to use—device; patients who really dislike injections may want to give it a go. "It’s a nice device," Zonzsein says. "And there may be a few patients who want to try it. But I see this as the second act of the same movie that’s already failed. It’s not going to work."

Mezitis says that some patients may really like the concept of an inhalable insulin: "A lot of people don’t want a syringe," he says. "This insulin may bring down the blood sugar faster than other forms of insulin."

Sources

Booton, Jennifer. "FDA Delays Afrezza Decision by Three Months, MannKind Shares Slump." Fox Business. 7 April 2014.  

Pollack, Andrew. "Inhaled Insulin Clears Hurdle Toward FDA Approval." 1 April 2014. The New York Times. 

Guettier, Jean-Marc, MD, CM. "Endocrinologic and Metabolic Drugs Advisory Committee Meeting on Afrezza: Introductory Remarks." 1 April 2014. U.S. Food and Drug Administration. 

"FDA Approves Afrezza to Treat Diabetes." US Food and Drug Administration. Page last updated June 27, 2014. 

"Insulin Basics." American Diabetes Association. Page last edited April 7, 2014. 

"Helping the Student with Diabetes Succeed: A Guide for School Personnel." National Diabetes Education Program/A Joint Program of the National Institutes of Health and the Centers for Disease Control and Prevention. Updated September 2010.