A 6-month, Randomised, Double-blind, Placebo-controlled, Multi-centre, Parallel-group, Phase II Study with an Optional Safety Extension Treatment Period up to 6 months, to Evaluate the Efficacy, Safety, and Tolerability of 3 Different Doses of AZD5069 Twice Daily as Add-on Treatment to Medium to High Dose Inhaled Corticosteroids (ICS) and Long-acting β2 Agonists (LABA), in Patients with Uncontrolled Persistent Asthma
