This is a Phase IIb, multi-centre, stratified, randomised, double-blind, double-dummy, parallel-group, placebo and active controlled study in children aged 5-11 years with persistent uncontrolled asthma. Subjects meeting all of the inclusion criteria and none of the exclusion criteria at the screening visit (Visit 1) will enter a four week run-in period during which time they will continue their current medications. Visit 2 will occur two weeks into the run-in period to allow a review of compliance with daily diary and run-in medication. At Visit 3 (end of run-in/randomization visit), subjects meeting the eligibility criteria who remain uncontrolled despite baseline therapy will be stratified based on pre screening inhaled corticosteroid (ICS) use. Once stratified, subjects will be randomised to the treatment phase of the study where they will receive one of five treatments for 12 weeks. Approx 1200 subjects ages 5 to 11 will be screened to achieve 575 randomized for a total of 115 randomized/evaluable subjects per treatment arm. Subjects will attend on-treatment visits at 2, 4, 8 and 12 weeks (Visits 4, 5, 6 and 7 respectively). A follow-up contact will be performed one week after completing study medication. All subjects must attempt spirometry measurements at Visits 1 and 3. For all subjects, a timed 24-hour urine collection for urinary cortisol and creatinine excretion will be performed prior to randomization at Visit 2 and within 7 days prior to Visit 7. All subjects must perform PEF daily between visits 1 and 7. The primary endpoint will be change from baseline in pre-dose (i.e. dosing trough) PM PEF from patient hand held electronic daily diary at Endpoint (Endpoint is defined as the mean over the last 7 days of treatment). Safety assessments include adverse events, oropharyngeal examinations, clinical chemistry, urinary cortisol, and vital signs.