 This is a randomized, non-placebo controlled study to evaluate the effects of Symbicort 400 mcg twice daily BID and Advair 250 mcg BID over 12 weeks. As the standard of therapy for COPD is a long-acting muscarinic antagonist LAMA treatment, a placebo only group cannot be ethically justified. The control arm of this study will thus be Oxeze 12 ug BID. The study will recruit approximately 69 subjects, from St. Pauls Hospital and British Columbia Cancer Agency, randomized 1:1:1 to the 3 arms in blocks. We anticipate 10 to 15 drop out rate, which will enable approximately 60 subjects for full analysis. 