INEXAS: A Phase 2 Randomised Trial of On-Demand Inhaled Interferon Beta-1a in Severe Asthmatics.

BACKGROUND Upper respiratory tract infections (URTI) are important triggers for asthma exacerbations. We hypothesised that inhalation of the anti-viral cytokine, interferon (IFN)-β, during URTI, could prevent these exacerbations.