- Respiratory Infection: Culture-documented or suspected bacterial or viral infection of the upper or lower respiratory tract, sinus or middle ear that is not resolved within 4 weeks of screening that led to a change in asthma management OR in the opinion of the Investigator, is expected to affect the subject's asthma status OR the subject's ability to participate in the study. However, subjects can be rescreened to allow for an adequate time period (of at least 4 weeks) between resolution of the infection and the date of randomisation.