Sentence: Our findings suggest that roflumilast reduces exacerbations and hospital admissions in patients with severe chronic obstructive pulmonary disease and chronic bronchitis who are at risk of frequent and severe exacerbations despite inhaled corticosteroid and longacting β2 agonist therapy , even in combination with tiotropium .
Drug combination annotation:
[{'class': 'POS', 'spans': ['roflumilast', 'tiotropium'], 'is_context_needed': False}]