LONDON, May 6 (Reuters) - After relying for years on itstop-selling lung drug Advair, GlaxoSmithKline is nowbraced for the worst in the form of cheap generics - but notjust yet.
Chief Executive Andrew Witty said on Wednesday that thechances of cheap copies of its highly profitable inhaledmedicine reaching the world's biggest market in 2016 were"vanishingly small".
For the first time, the drugmaker has factored in theintroduction of a generic alternative to Advair in the UnitedStates in making assumptions about its sales prospects over thenext five years.
Witty said this could in theory mean annual U.S. sales ofAdvair falling to less than 300 million pounds ($457 million) by2020, down from 392 million pounds in the first quarter of 2015or 1.57 billion on an annualised basis.
However, Witty stressed at an analyst meeting that it wasstill unclear if or when generics would arrive in the UnitedStates, adding there had been "no change" in the company's viewof the likelihood of copycat versions being launched.
"Clearly, if there was no generic Advair in the U.S. thatwould be an upside to the guidance we've given you for thepharmaceuticals business," he said.
GSK expects pharmaceuticals sales to grow at a low singledigit annual rate between 2016 and 2020, with the possibleintroduction of generic Advair in the U.S. factored in.
($1 = 0.6560 pounds) (Reporting by Ben Hirschler; Editing by Elaine Hardcastle)