Growing Warnings About Asthma Drug
Asthma Drug Salmeterol
University of Iowa asthma experts are trying to ensure that an asthma drug combination is prescribed only when truly necessary.
The long-acting asthma drug salmeterol used in combination with an inhaled corticosteroid can dangerously worsen asthma for a small subgroup of people with the condition.
In a letter published in the Aug. 24 issue of the New England Journal of Medicine (NEJM), the UI physicians reported two cases representing the few patients for whom the combination can make asthma more severe or even fatal.
"For most patients whose asthma cannot be controlled with a low-dose inhaled steroid, adding salmeterol to the steroid provides increased benefits. So there's no question this can be a useful combination drug for many individuals," said Miles Weinberger, M.D., professor of pediatrics in the University of Iowa Roy J. and Lucille A. Carver College of Medicine.
"However, some patients are receiving the combination drug but don't actually need it, and there is at least a small subgroup of patients for whom previous research showed the salmeterol-steroid combination has a very negative, rather than beneficial, effect," said Weinberger, who also directs the UI Division of Pediatric Allergy and Pulmonary Diseases.
Advair, made by GlaxoSmithKine, contains salmeterol in addition to an inhaled corticosteroid and is extensively marketed, Weinberger said. It is one of the most commonly prescribed maintenance asthma medications in the United States and is meant to be used by patients on a regular, preventive basis, not to treat sudden asthma attacks.
"We do not want to unduly alarm people, but instead help spread the word that patients should talk with their physicians if they are using Advair, or another inhaled asthma medication that contains salmeterol and feel that it worsens symptoms instead of making them better," Weinberger said.
The UI physicians' letter follows up a related editorial published December 2005 in the NEJM by Fernando Martinez, M.D., a leading asthma expert. The letter also helps illustrate findings reported this year in a large, population-based study in the United States that is consistent with a previous study in England.
The U.S. study showed a very small, but statistically significant, increased risk of asthma-related deaths - 13 among 13,000 individuals who received salmeterol but only three among another 13,000 individuals who received a placebo during a 28-week treatment period. Other studies have suggested that some people have a genetic variation that causes them to respond negatively to the class of medications that includes salmeterol, Weinberger said.
The concern about salmeterol and a related medication, formoterol, led the U.S. Food and Drug Administration this year to add a "black box" warning to products containing these medications.
The warning is appropriate, Weinberger said, but many people, including health care professionals, remain unaware of the problem. To raise awareness, Weinberger and Mutasim Abu-Hasan, M.D., UI clinical associate professor of pediatrics, documented two cases they saw at the UI that showed the risk of these medications.
Each of the two patients had life-threatening problems related to salmeterol use. When the patients switched to a different asthma medication, their asthma was successfully managed.
Weinberger emphasized that people currently taking asthma medication that contains salmeterol should continue taking it until they consult their physicians.
"For many patients, adding salmeterol to an inhaled corticosteroid provides additional clinical benefit. Patients should contact their physicians if they notice their response to a 'rescue' inhaler such as albuterol is lessened when they're taking salmeterol as part of a regular maintenance medication," he said.
Weinberger said that many primary care physicians, partly in response to heavy drug marketing, immediately start patients on the combination drug instead of first trying the inhaled steroid alone.
"We want to build on Dr. Martinez's recommendation and encourage primary care physicians to start asthma patients on just the inhaled steroid as a regular maintenance medication and then add the salmeterol by using a combination product only if the person's asthma symptoms are not adequately controlled," Weinberger said.
Nearly 20 percent of all children have some degree of asthma. At least 6 percent of adults have asthma, as well.
It is not currently possible to test each patient with asthma to see if he or she has genetic risk factors for a bad reaction to Advair. The genetic testing is not commercially available, and all the genetic variations that could contribute to the problem are not yet known.