WASHINGTON — Two federal drug officials have concluded thatasthma sufferers risk death if they continue to use four hugely popular asthma drugs — Advair, Symbicort, Serevent and Foradil. But the officials’ views are not universally shared within the government.
The two officials, who work in the safety division of the Food and Drug Administration, wrote in an assessment on the agency’s Web site on Friday that asthma sufferers of all ages should no longer take the medicines. A third drug-safety official concluded that Advair and Symbicort could be used by adults but that all four drugs should no longer be used by people age 17 and under.
Dr. Badrul A. Chowdhury, director of the division of pulmonary and allergy products at the agency, cautioned in his own assessment that the risk of death associated with the drugs was small and that banning their use “would be an extreme approach” that could lead asthmatics to rely on other risky medications.
Once unheard of, public disagreements among agency experts have occurred on occasion in recent years. The agency is convening a committee of experts on Wednesday and Thursday to sort out the disagreement, which has divided not only the F.D.A. but also clinicians and experts for more than a decade.
Sudden deaths among asthmatics still clutching their inhalers have fed the debate. But trying to determine whether the deaths were caused by patients’ breathing problems or the inhalers has proved difficult.
The stakes for drug makers are high. Advair sales last year were $6.9 billion and may approach $8 billion this year, making the medication GlaxoSmithKline’s biggest seller and one of the biggest-selling drugs in the world. Glaxo also sells Serevent, which had $538 million in sales last year. Symbicort is made by AstraZeneca and Foradil by Novartis.
Whatever the committee’s decision, the drugs will almost certainly remain on the market because even the agency’s drug-safety officials concluded that they were useful in patients suffering from chronic obstructive pulmonary disease, nearly all of whom are elderly.
Dr. Katharine Knobil, global clinical vice president for Glaxo, dismissed the conclusions of the agency’s drug-safety division as “not supported by their own data.” Dr. Knobil said that Advair was safe and that Serevent was safe when used with a steroid.
Michele Meeker, a spokeswoman for AstraZeneca, said that the F.D.A.’s safety division improperly excluded most studies of Symbicort in its analysis, and that a review of all of the information shows that the drug does not increase the risks of death or hospitalization.
Dr. Daniel Frattarelli, a Detroit pediatrician and member of the American Academy of Pediatrics’s committee on drugs, said that he was treating children with Advair and that his committee had recently discussed the safety of the medicines.
“Most of us felt these were pretty good drugs,” Dr. Frattarelli said. “I’m really looking forward to hearing what the F.D.A. committee decides.”
About 9 percent of Advair’s prescriptions go to those age 17 and under, according to Glaxo. Ms. Meeker could not provide similar figures for Symbicort.
In 1994, Serevent was approved for sale, and the F.D.A. began receiving reports of deaths. A letter to the New England Journal of Medicine described two elderly patients who died holding Serevent inhalers. Glaxo warned patients that the medicine, unlike albuterol, does not work instantly and should not be used during an attack.
In 1996, Glaxo began a study of Serevent’s safety, but the company refused for years to report the results publicly. In 2001, the company introduced Advair, whose sales quickly cannibalized those of Serevent and then far surpassed them.
Finally in 2003, Glaxo reported the results of its Serevent study, which showed that those given the medicine were more likely to die than those given placebo inhalers. Glaxo said problems with the trial made its results impossible to interpret.
Asthma is caused when airways within the lungs spasm and swell, restricting the supply of oxygen. The two primary treatments are steroids, which reduce swelling, and beta agonists, which treat spasms. Rescue inhalers usually contain albuterol, which is a beta agonist with limited duration. Serevent and Foradil are both beta agonists but have a longer duration than albuterol and were intended to be taken daily to prevent attacks.
Advair contains Serevent and a steroid. Symbicort, introduced last year, contains Foradil and a steroid. In the first nine months of this year, Symbicort had $209 million in sales.
The problem with albuterol is that it seems to make patients’ lungs more vulnerable to severe attacks, which is why asthmatics are advised to use their rescue inhalers only when needed. The long-acting beta agonists may have the same risks.
But drug makers say this risk disappears when long-acting beta agonists are paired with steroids. The labels that accompany Serevent and Foradil instruct doctors to pair the medicines with an inhaled steroid.
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