This is a Phase II, pilot randomized double blind control study, meaning this study will help assess if this research can be expanded to evaluate Ig treatment in patients with COPD. Ig treatment is a sterile solution of human immunoglobulin proteins given intravenously (in the vein). Immunoglobulins are part of the immune system and help the body fight infections. Participants will be assigned to either receiving the Ig treatment or normal saline as a control product every 4 weeks for 12 months.