HMI World | Printer-Friendly

MAY / JUNE 2006

AROUND HARVARD

This article originally appeared in the April 2006 Harvard Women’s Health Watch and is provided courtesy of Harvard Health Publications.

Insulin by inhaler: New option for diabetes treatment
For the first time since the introduction of insulin more than 80 years ago, a non-injectable way of taking the hormone will be available. Exubera, a fast-acting inhaled insulin, was approved by the FDA in January 2006 and should be on the market by mid-year. Pfizer, which developed the drug and inhaler with Sanofi-Aventis and Nektar Therapeutics, says that a needle-free option will benefit people with diabetes who need insulin but delay treatment because they fear the injections.

More than five million people in the United States must inject insulin daily. People with type 1 diabetes, a form that usually develops at an early age, stop producing insulin. People with type 2 diabetes, which usually shows up in adulthood and is linked to obesity, continue to make insulin, but the body doesn’t respond normally. This “insulin resistance” causes blood sugar to rise. Blood sugars that remain out of control can result in serious complications, including heart disease, kidney failure, vision loss, and nerve damage. Insulin therapy is the only option for people with type 1. Type 2 diabetes can usually be managed through diet, exercise, and oral medications, but some people also need insulin injections.

Exubera doesn’t eliminate insulin shots, but it can mean fewer of them. People with type 1 diabetes, for example, use both long-acting and fast-acting insulins to keep blood sugar even throughout the day. At mealtime, Exubera may be a more convenient way of taking fast-acting insulin than an injection. In type 2 diabetes, inhaled insulin can be used alone or with diabetes pills or long-acting insulins.

In clinical studies involving adults with both types of diabetes, Exubera controlled blood sugar levels as well as injected insulin. And it reached peak concentrations more quickly. One potential drawback is that dosing may be less precise: It’s hard to know exactly how much of the medication is actually absorbed by the lungs. Users must continue to carefully monitor their blood sugar levels.

Another concern is the potential for lung damage. Some study subjects experienced coughing or slightly reduced lung capacity while using Exubera. Pfizer will conduct post-marketing studies to track the long-term effects of Exubera and to examine its risks and benefits in people with lung disease. According to the FDA, people with emphysema, bronchitis, or asthma should not use Exubera, nor should smokers or those who’ve quit smoking only within the past six months. The FDA also recommends that tests of lung function be given before starting Exubera, after the first six months of treatment, and yearly thereafter.

How do you take it?
The Exubera inhalation device is somewhat larger than other types of handheld inhalers, such as those used to treat asthma. When open, it extends from the mouth to the middle of the chest (see photo). The top portion is a clear chamber with a mouthpiece on top; the bottom holds a packet of powdered insulin. You pump a handle and press a button in the bottom portion to release the insulin into the chamber and breathe in normally through the mouthpiece. When closed, the inhaler is about the size of a standard flashlight.