This study is testing a new medicine, called AZD6793, for people with moderate to very severe Chronic Obstructive Pulmonary Disease (COPD). COPD is a lung disease that makes it hard to breathe. The study will compare three different doses of AZD6793 to a placebo (a pill with no medicine) to see how well it works and if it's safe. It will last 24 weeks (about 6 months) and involve about 1160 participants worldwide.

To join, you must be 40 or older, have had COPD for at least a year, and have a certain level of breathing difficulty. You also need to have experienced recent worsening of symptoms and be on a stable medication plan. Current or past smokers with a history of smoking are eligible, but other lung diseases or serious health issues may disqualify you.

• The study requires several doctor visits over 6 months.
• Participants will be randomly given one of three doses or a placebo.
• There may be risks or side effects from taking the study medication.