In a statement on Friday, the British drugmaker said a 52-week safety study, the last in a program of trials which also included four pivotal studies of the drug, was now complete.

GSK, which is developing the LAMA/LABA combination medicine with Theravance, said in July that it had showed positive results in four late-stage trials in patients with chronic obstructive pulmonary disease (COPD).

"The full results of all these studies ... will be presented at future scientific meetings," the firm said.

LAMA/LABA is a combination of two molecules - umeclidinium bromide (UMEC), a long-acting muscarinic antagonist (LAMA) and vilanterol (VI), a long-acting beta2 agonist (LABA), administered by a new dry powder inhaler.

GSK is working hard to develop next-generation medicines to become successors to its $8 billion lung drug Advair.

Advair and Pfizer's Spiriva currently dominate the respiratory drug market, but Swiss firm Novartis is also fighting the next generation battle with its experimental combination drug QVA149, which some analysts are already tipping as a potential $5 billion-a-year seller.

(Reporting by Kate Kelland; Editing by Greg Mahlich)

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