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March 17 (Reuters) - GlaxoSmithKline Plc's respiratory treatment for chronic breathing problems did notshow any new safety problems while being tested to treat asthma,a preliminary review by U.S. Food and Drug Administration stafffound.
The review comes two days ahead of a meeting of FDA advisersto discuss the combination treatment, Breo Ellipta, andrecommend whether it should be approved to treat asthma.
The inhaled drug combination of a corticosteroid andvilanterol is already approved to treat chronic obstructivepulmonary disease, a breathing disability that gets worse withtime and affects mostly smokers.
Corticosteroids smoothen the inner surface of breathingpathways.
Vilanterol belongs to a class of compounds calledlong-acting beta-adrenoceptor agonists (LABA) that havehistorically been linked to asthma-related deaths. Glaxolicensed vilanterol from Theravance Inc in 2002.
Data showing Breo Ellipta's LABA component delayed theworsening of asthma symptoms could sway the FDA panel in itsfavor, analysts from Robert W. Baird & Co said last week.
The FDA staff said on Tuesday there were no asthma-relateddeaths in Breo Ellipta studies it reviewed and that data onasthma-related hospitalizations were not observed uniformly inthe 23 studies that Glaxo conducted. (http://1.usa.gov/1Fvj3r9)
The data submitted by Glaxo showed that the safety profileof Breo Ellipta to treat asthma was similar to that of othercombinations of steroids and LABA compounds, the FDA staff said.
They also said advisers would discuss the fact that thebenefit of adding a LABA compound to a steroid was notdemonstrated consistently in the trials.
Glaxo has three respiratory treatments on the market with aLABA compound and each of them carry a warning that the drugcould increase the risk of asthma-related deaths.
This possible side-effect was verified in a study thattested another one of Glaxo's LABA compounds, salmeterol,against a placebo.
Salmeterol, which is approved in the United States under thebrand name Serevent Diskus to treat asthma but only incombination with an inhaled steroid, has been available on themarket since 1994. (Reporting by Vidya L Nathan and Amrutha Penumudi in Bengaluru;Editing by Savio D'Souza)
