The purpose of this study is to characterize the bronchodilator effect, systemic exposure and safety/tolerability of two different doses of inhaled glycopyrronium, when compared to placebo. Outcome of this study will be used to determine the dose of inhaled glycopyrronium for the development of fixed dose combination indacaterol/mometasone/glycopyrronium (QVM149) for children aged 6 to less than 12 years old with moderate to severe asthma.