Extension Study of Safety and Tolerability of DDY391 in Participants With Moderate to Severe Psoriatic Arthritis (CDDY391A12201-extension)

This is a 1-year open label extension (OLE) for participants who completed study treatment in CDDY391A12201 core study. Eligible participants include adults with moderate to severe PsA enrolled in part A or B of the core study who had an inadequate response and/or intolerance to biologic disease-modifying antirheumatic drugs (bDMARDs), as well as biologic-naïve participants with an inadequate response and/or intolerance to at least one conventional synthetic DMARD. Participants must not meet any core study treatment discontinuation criteria at OLE enrollment. There will be no screening period in this trial. The OLE baseline visit will coincide with Week 12/EOT for Part A and Week 24/EOT for Part B. Eligible participants will receive open-label DDY391 for up to 52 weeks, followed by a 30-day safety follow-up. The total study duration is 56 weeks.