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LONDON, July 23 (Reuters) - GlaxoSmithKline's salesfell by a worse-than-expected 13 percent in the second quarteras its all-important lung drugs struggled in the United Statesand a strong pound took a bite out of growth.
A run of weak quarters highlights the pressure on ChiefExecutive Andrew Witty, whose drive to reshape Britain's biggestdrugmaker has yet to deliver the hoped-for return to sustainedrevenue growth, following a lengthy period of patent expiries.
The company is also mired in a serious corruption scandal inChina, where it has been accused of paying bribes to doctors touse its medicines.
Quarterly sales totalled 5.56 billion pounds ($9.48billion), generating "core" earnings per share down 25 percentat 19.1 pence, the drugmaker said on Wednesday.
Analysts, on average, had forecast sales of 5.76 billionpounds and core EPS, which excludes certain items, of 21.3pence, according to Thomson Reuters.
The company cut its outlook for the full year, predictingcore EPS would be "broadly similar to 2013" in constant exchangerate terms. Previously, it had been hoping to increase 2014 EPSby between 4 and 8 percent.
A big concern for GSK investors is its reliance on theinhaled lung drug Advair, which makes up nearly a fifth ofsales. It already faces competition from copycat versions inEurope, with generics in the United States perhaps a couple ofyears away.
GSK is hoping two new inhaled respiratory medicines - Breoand Anoro - will fill the gap but their uptake so far has beslow, disappointing many analysts who follow the company.
Although it has put the worst of its patent losses behindit, GSK still faces challenges in some areas, including thelaunch of a generic version of heart pill Lovaza in the U.S.market in April.
Witty joined the deal-making bandwagon sweeping thehealthcare sector in April by trading more than $20 billion ofassets with Swiss rival Novartis in a complexthree-part transaction designed to make the group more focused.
But the GSK boss has eschewed full-scale mega-mergers,arguing they are distracting and disruptive to the company'sresearch and development activities. ($1 = 0.5865 British Pounds) (Reporting by Ben Hirschler; Editing by Kate Kelland)
