The purpose of this study is to assess the effects of different medication on the rate of worsening of COPD symptoms. You are being asked to participate in this research study because you have moderate to very severe COPD and a history of COPD exacerbations.
The purpose of the study is to evaluate the safety and effectiveness of a single inhaler therapy versus multi-inhaler therapy for patients with COPD.
The purpose of the study is to look at the effects of four different doses of an experimental inhalers compared to a placebo and a marketed version of another inhaler on subjects with COPD.
A clinical research study is a medical study that helps to answer important questions about if and how well an investigational drug works and how safe it is. This study will look at how well the drug being studied (RPL554) works, how safe it is and how the body processes it (called pharmacokinetics) in subjects with COPD.