A Study to Investigate Efficacy and Safety of AZD1163 in Participants With Rheumatoid Arthritis This study is for people with rheumatoid arthritis (RA), a disease where the body's immune system attacks its own joints, causing pain and swelling. The study tests a new medicine called AZD1163, which works by blocking certain enzymes that make proteins harmful to RA patients. Participants will be randomly placed into one of four groups. Each group will receive different doses of AZD1163 or a placebo (a substance with no active drug), along with their regular RA medicine. The study lasts for 24 weeks, followed by 28 weeks of monitoring to check for any side effects or changes. Key Points for Participants:

• The study involves regular visits and injections for 52 weeks.
• Participants must have moderate-to-severe RA and test positive for an antibody known as ACPA.
• Cannot participate if using certain other RA treatments or have another autoimmune condition.

The goal is to see if AZD1163 is safe and effective in reducing RA symptoms. Participants help advance RA research and may find relief from their symptoms.