The end is near for CFC-propelled inhalers

Washington -- The clock is running down for albuterol metered-dose inhalers that rely on the ozone-depleting propellant chlorofluorocarbon, or CFC. Doctors are being urged to help the many patients who still use them to switch to hydrofluoroalkane, or HFA, devices before Dec. 31.

That will be the last day that the CFC inhalers can be sold in the U.S.

Patients should be reassured that the albuterol inhalers utilizing the more environmentally friendly HFA propellant will contain the same medicine as did CFC devices and have been shown to be safe and effective in studies. But important differences exist, according to the Food and Drug Administration and asthma and allergy specialists.

"They taste different. The mix may be softer. HFA albuterol inhalers may clog," said Badrul Chowdhury, MD, PhD, director of the FDA's division of pulmonary and allergy drug products, during a May 30 briefing.

Millions of patients still use the CFC inhalers. Dr. Chowdhury estimated that about 65% of albuterol in the U.S. is HFA-propelled and the rest is CFC-propelled.

Albuterol is one of the top 10 prescribed medications in the country with approximately 52 million prescriptions written every year, he said. The drugs are used as quick-relief "rescue" medications for wheezing and shortness of breath in patients with asthma and chronic obstructive pulmonary disease.

Some patients would very much like to hold on to their CFC inhalers. They argue that the HFA inhalers, which have been on the market for about a decade, cause more adverse reactions -- a charge disputed by the FDA. They also say HFA versions are more expensive than the older devices -- a point on which all agree.

A petition is circulating on the Internet urging Congress and the Bush administration to act to save CFC inhalers permanently. But that is not likely. Beginning Jan. 1, 2009, the CFC-propelled albuterol inhalers no longer will be available in the U.S.

This change is a result of the Clean Air Act and an international environmental treaty, the Montreal Protocol on Substances that Deplete the Ozone Layer. Under that accord, the United States agreed to phase out production and importation of ozone-depleting substances, including CFCs.

The transition already has taken place for most products that use CFCs.

Medical uses that were deemed essential, however, such as albuterol MDIs, were exempt. That exemption expires on the last day of this year.

"No CFC-propelled albuterol inhalers may be produced, marketed or sold in the U.S. after Dec. 31," said Deborah Henderson, a senior adviser in the FDA's Office of Executive Programs.

"Patients who purchase CFC-propelled inhalers before Dec. 31 may continue to use them, but no CFC inhalers will be available for sale after that date," Henderson said. Only one company still manufactures the CFC devices.

The options

Three HFA albuterol inhalers have been approved by the FDA: Proair HFA Inhalation Aerosol, Proventil HFA Inhalation Aerosol and Ventolin HFA Inhalation Aerosol. In addition, an HFA-propelled inhaler containing levalbuterol, a medicine similar to albuterol, is available as Xopenex HFA Inhalation Aerosol.

All are brand-name products. Because no HFA generics are available, the cost will be greater than CFC inhalers. Generic CFC inhalers were available and "dirt cheap," said Jay Portnoy, MD, president of the American College of Allergy, Asthma & Immunology and chief of the allergy section at Children's Mercy Hospitals and Clinics in Kansas City, Mo.

Prices for CFC inhalers range from $5 to $25, while an HFA inhaler costs $30 to $60. Manufacturers currently are offering discounts to those who can't afford them, and some offer everyone a price reduction on an initial purchase.

There are other important differences between the two inhalers, and physicians are finding that education is important. "Problems are encountered where patients are not being educated," Dr. Portnoy said.

"Patients need to be told that the spray is gentle to the point where they don't think they are receiving any medication at all. But they are," said Paul A. Greenberger, MD, president-elect of the American Academy of Allergy Asthma & Immunology and a professor of medicine at Northwestern University's Feinberg School of Medicine in Chicago.

"Patients used to feel something in the back of their throat, but this is different," Dr. Greenberger said.

"Patients also need to rinse the mouthpiece in water once a week to keep the device effective," he noted. Priming also is required more frequently with the HFA devices, especially if they haven't been used for some time.

Education opportunity

Some physicians are finding that the transition provides an opportunity to educate patients on the effective use of inhalers in general. "Fewer than 50% of patients really use them correctly," said Norman H. Edelman, MD, chief medical officer at the American Lung Assn.

For those having extensive post-switch problems, spacers may be the answer. Very young and very old patients may find it easier to squirt the metered dose into the spacer tube and breath in and out until the drug has been inhaled, Dr. Edelman said.

Patient education about the new inhalers also could provide an opportunity to explain that albuterol inhalers are not to be used as maintenance or controller drugs, said Dr. Greenberger.

"It's one thing to use albuterol as a pretreatment before exercise. But if they are using it every night, that's a different kind of asthma," he said. "Albuterol is not the answer. It's a good drug, but it's best for intermittent use."