A Study to Investigate Efficacy and Safety of AZD1163 in Participants With Rheumatoid Arthritis

Phase II study in participants with moderately-to-severely active rheumatoid Arthritis (RA) to evaluate efficacy and safety of AZD1163.

* Inclusion * Diagnosed with adult-onset RA as defined by the 2010 ACR/EULAR classification criteria for at least 12 weeks prior to screening. * Moderately-to-severely active RA as defined by: a. \>= 6 swollen joints on 66SJC and \>= 6 tender joints on 68TJC; b. CRP \> upper limit of normal. * Have a positive ACPA at screening. * A history of inadequate response, or loss of response, or intolerance to: a. at least one csDMARD treatment, AND/OR b. At least one and at most 2 TNFi. * A history of at least 12 weeks treatment and \>= 4 weeks stable on a csDMARD and/or SC TNFi prior to the day of randomisation. * Exclusion * History or evidence of an alternate autoimmune or other condition that could confound the diagnosis of RA. Participants with RA and secondary Sjogren's disease are eligible. * Have received or planning to receive any biologic DMARDs (except for TNFi) or targeted synthetic DMARDs.