Vol. 18 •Issue 1 • Page 16
New Breed of Asthma MDIs:
Familiar Drugs Take New Shape
Sitting at home reading a magazine one Sunday afternoon, Kevin came across an interesting article about asthma treatments. The headline of the article proclaimed: “Changes Coming to Asthma Inhalers.”
Kevin raised an eyebrow when he was reading the story because his 10-year-old son, Paul, has asthma and uses an inhaler regularly. The article noted the inhalers many asthmatics are using today may not be available soon.
Kevin began to worry about Paul’s health. “What will we do?” he asked aloud.
According to information published on the American Academy of Allergy, Asthma and Immunology Web site, there is a new generation of asthma inhalers on the horizon.
Paul V. Williams, MD, FAAAAI, a clinical allergist and a member of the AAAAI Pharmacotherapeutics Committee, explained the importance of the new breed of inhalers.
“Several years ago, the United States signed a treaty with several other countries, agreeing to stop using substances called CFCs (chlorofluorocarbons),” noted Williams.
Chlorofluorocarbons have been shown to add to the destruction of the atmospheric ozone layer, which protects us from the harmful rays of the sun. In the past, CFCs have had many uses, primarily as refrigerants in refrigerators and air conditioners and as propellants for aerosols.
Treaty Exemption to End
“For the past several years, asthma inhalers have received a medical exemption from the treaty, so you could still use your inhalers even though they still used CFCs as propellants,” explained Williams. “Those exemptions will no longer be granted after 2005, so the FDA and organizations involved with people with asthma are trying to set up a gentle transition from the old inhalers to the new inhalers.”
Slowly, doctors have been working to change their patients’ MDI regiments. Dry Powder Inhalers or DPIs are one option many physicians are considering.
“Currently, there aren’t as many medicines available in non-CFC forms, so you may have to change brands of medicine, but not types of medicine,” explained Williams. “If you are using an inhaled steroid, you will still be able to use an inhaled steroid. Your rescue medicine, which for most people is albuterol, will still be available.”
DPIs emit dry powder and do not use a propellant. They can however, as do MDIs, cause significant deposition of drug in the mouth and throat which, as well as reducing drug delivery to the lungs, can also cause local side effects. In addition, DPIs emit powder with a low fine particle fraction, and lung deposition is dependent on the force with which the patient can inhale.
“These new inhalers still have to pass the same strict standards that all medicines have to pass, and the FDA makes sure that the drugs are effective and safe for the treatment of asthma,” explained Williams. “These medicines, in most cases, will be the same medicines that are used today for the treatment of asthma; they will just be using different devices to deliver the medicine to the lungs. There is some suggestion that the new inhalers may actually be more effective than the old ones.”
The other type of inhaler that will be used in the future is very similar to the metered-dose inhaler currently used by many asthma patients today.
“It simply uses a different propellant, one called HFA,” said Williams. “The new MDI may have a different taste and less force, but it will be used in the same way.
An Eye to Cost
According to Williams, the cost of the medications is the biggest problem right now. Some of the medicines to be replaced are now available in generic form, and replacing them with brand-name drugs will result in higher costs.
The FDA and several asthma support organizations like the American Academy of Asthma, Allergy and Immunology, the American Lung Association, Asthma and Allergy Foundation of America and Allergy & Asthma Network/Mothers of Asthmatics, to name a few, are working to ensure that these medicines will be available at costs that aren’t far different from what current users are paying now.
Marc Willis is a South Carolina television reporter.