UPDATE 3-US FDA panel: Two asthma drugs risky but Advair OK

(Adds comment from FDA official)

By Lisa Richwine

ROCKVILLE, Md., Dec 11 (Reuters) - GlaxoSmithKline Plc's (GSK.L) widely prescribed drug Advair is safe enough for treating asthma but two lesser-used medicines are too risky, a U.S. advisory panel ruled on Thursday.

Evidence of asthma-related deaths and serious complications led the panel of experts to warn against continued use of Glaxo's Serevent and Novartis AG's (NOVN.VX) Foradil for adults, adolescents and children with asthma.

AstraZeneca Plc's (AZN.L) Symbicort also was deemed safe alongside Advair.

All of the inhaled drugs contain long-acting beta agonists, but Advair and Symbicort add a steroid, which the panel felt made the medicines less risky.

"It looks like use of LABAs alone is more dangerous," said consumer advocate Sidney Wolfe, director of Public Citizen's Health Research Group.

The U.S. Food and Drug Administration will consider the recommendations as officials decide if the drugs should continue to be approved for treating asthma.

Patients should not stop taking any of their asthma medications without consulting a doctor, John Jenkins, head of the FDA's Office of New Drugs, advised after the meeting.

Glaxo shares rose 1.8 percent after the panel vote to close at $36.08 on the New York Stock Exchange.

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.

Serevent sales were much smaller at $376 million. Schering-Plough Corp (SGP.N), which markets Foradil in the United States, reported sales of $76 million for that drug.

Staff within the FDA told the panel they were split on how to proceed. Drug-safety reviewers urged limits, including withdrawing the asthma approval for all of the medicines in children. Experts in another division that reviews asthma drugs said the numbers of deaths and serious complications were small and risks were manageable with appropriate warnings.

An FDA analysis found 2.8 more serious asthma-related complications, including deaths and hospitalizations, for every 1,000 patients treated with a LABA.

Asthma is 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 attacks that can be fatal.

Millions of asthma patients use LABAs to help keep their airways open. Doctors on the FDA panel said the drugs offered important benefits for their patients.