<p>Chronic obstructive pulmonary disease (COPD) is an inflammatory disorder of the lungs that affects about 10% of the adult population and is currently the third leading global cause of death. COPD is the result of multiple, repeated and dynamic gene–environment interactions, starting early in life, that determine the lung function trajectory that a given individual follows over a lifetime. Increasing understanding of COPD pathogenesis has opened many new opportunities for drug development, including recently approved monoclonal antibodies that reduce inflammatory cytokine signalling by targeting the IL-4α receptor or the eosinophil-activating IL-5. Drugs targeting a range of other culprits involved in COPD, including neutrophils, alarmins and kinases, are also in clinical development. As the current pipeline of drugs in development for COPD matures, potential areas for novel therapies continue to emerge while lessons from ongoing trials such as patient stratification can be used to refine the design of future trials in this disease.</p>