UPDATE 1-Glaxo rotavirus vaccine appears safe--US FDA panel

(Adds panel member comments, details from meeting, byline)

By Kim Dixon

GAITHERSBURG, Md., Feb 20 (Reuters) - GlaxoSmithKline Plc's (GSK.L: Quote, Profile, Research, Stock Buzz) infant vaccine to prevent diarrhea caused by the rotavirus appears safe and effective, based on available data, U.S. advisers said on Wednesday.

The Food and Drug Administration advisory panel voted that the 11 studies submitted by GlaxoSmithKline support the use of the oral vaccine, which aims to prevent severe infant diarrhea often caused by infection with the virus.

The FDA typically takes the advice of its expert panels.

The vaccine, called Rotarix and already approved in many countries, could compete with Merck & Co Inc's (MRK.N: Quote, Profile, Research, Stock Buzz) RotaTeq vaccine in the United States, if approved by the FDA.

Approval in the United States could intensify the rivalry between the two drugmakers.

In a briefing prepared for the meeting, FDA staff had noted a statistically significant increase in deaths related to pneumonia compared with placebo in Glaxo's largest trial.

The panel was unanimous the vaccine appeared effective and voted 11-1 that it appeared safe. Most members were convinced by Glaxo's argument the pneumonia deaths were an isolated finding from a single study likely not due to the vaccine itself.