U.S. FDA panel hears risks with asthma drug

U.S. drug reviewers presented evidence of life-threatening risks from a class of asthma drugs on Wednesday to an advisory panel considering whether to recommend limits on medicines now used by millions.

The inhaled drugs include one of the world’s top-sellers, GlaxoSmithKline PLC’s Advair, as well as AstraZeneca PLC’s blockbuster Symbicort.

A higher, although small, number of deaths was seen when Food and Drug Administration reviewers combed data from 110 clinical trials involving about 61,000 people.

The analysis found 2.8 more serious asthma-related complications, including deaths and hospitalizations, for every 1,000 patients treated with one of the drugs known as long-acting beta agonists, or LABAs.

“There was a clear trend of lower age groups at higher risk,” said FDA statistician Mark Levenson. Some LABAs are cleared for treating children as young as four.

Advair and Symbicort combine a LABA with an inhaled steroid. Glaxo’s Serevent and Novartis AG’s Foradil, which Schering-Plough Corp markets in the United States, contain LABAs alone.

All of the makers say the drugs are safe and offer important benefits for asthma patients.

Reviewers in the FDA’s drug safety office have recommended revoking the medicines’ approval for treating asthma in children, according to documents prepared for the panel.

The reviewers also said Serevent and Foradil, which are used much less often, should not be taken by anyone with asthma.

The FDA is undecided on how to proceed and is seeking input from the panel of outside experts.

Advair is Glaxo’s best-selling drug with $5.6 billion in worldwide sales through the first nine months of the year. Symbicort’s sales for the same period were $1.5 billion.

Asthma is a chronic disease marked by restricted breathing and wheezing and is often made worse by exercise, cigarette smoke and other factors. About 20 million people in the United States have asthma, according to the National Institutes of Health.

Uncontrolled asthma can lead to potentially fatal attacks.

LABAs help relax airways to prevent spasms but come with strong warnings about a higher risk of asthma-related deaths in light of findings from a Glaxo study halted in 2003.

The advisory panel is set to vote Thursday on whether the benefits of each drug outweigh its risks for asthma patients. The FDA usually follows panel recommendations.

Approval for asthma could be revoked, but sales would continue as all of the drugs are also approved for treating chronic obstructive pulmonary disease.

The manufacturers were due to speak to the panel later on Wednesday.

Glaxo has argued that adding a steroid to a LABA, as in Advair, protects against serious risks, although FDA staff have questioned that idea.

“Evidence that (an inhaled steroid) nullifies the LABA-related risk is lacking,” FDA drug safety reviewer Andrew Mosholder said.

AstraZeneca says its own analysis showed no serious risks in patients who took formoterol, the LABA in Symbicort. Novartis and Schering-Plough also have said Foradil is safe.

By Lisa Richwine
ROCKVILLE, Md. (Reuters)