Rivals Novartis ($NVS) and Boehringer Ingelheim are boasting positive results for their combination COPD treatments, duking it out with GlaxoSmithKline ($GSK) for dominance of a market that could reach $14 billion by 2018.

In Phase III data on a fixed-dose combo of the LAMA tiotropium and LABA olodaterol, Boehringer said its cocktail improved the lung function of COPD sufferers, beating out placebo and each drug on its own. For its part, Novartis reported that its LABA-LAMA combination, marketed in Europe as Ultibro, topped tiotropium and formoterol in a 900-patient trial. Boehringer is yet to submit its tag-team bronchodilator for approval in any country, and Novartis is still gearing up for an FDA submission for its treatment. GlaxoSmithKline is the only LABA-LAMA contender on the U.S. market, winning FDA approval for its Anoro Ellipta last year, and the U.K. drugmaker picked up an EU nod for the inhaler this month.