A Study Evaluating the Efficacy and Safety of Guselkumab Administered Subcutaneously in Participants With Active Psoriatic Arthritis Including Those Previously Treated With Biologic Anti -Tumor Necrosis Factor (TNF) Alpha Agent(s)

Inclusion Criteria:

• Have a diagnosis of Psoriatic Arthritis (PsA) for at least 6 months before the firstadministration of study agent and meet Classification criteria for Psoriatic Arthritis (CASPAR) at screening
• Have active PsA as defined by: at least 3 swollen joints and at least 3 tender jointsat screening and at baseline; and C-reactive protein (CRP) greater than or equal to (>=) 0.3 milligram per deciLitre (mg/dL) at screening from the central laboratory
• Have at least 1 of the PsA subsets: distal interphalangeal joint involvement,polyarticular arthritis with absence of rheumatoid nodules, arthritis mutilans,asymmetric peripheral arthritis, or spondylitis with peripheral arthritis
• Have active plaque psoriasis, with at least one psoriatic plaque of >= 2 centimeter (cm) diameter or nail changes consistent with psoriasis or documented history ofplaque psoriasis
• Have active PsA despite previous non-biologic disease-modifying antirheumatic drugs (DMARD), apremilast, and/or nonsteroidal anti-inflammatory drug (NSAID) therapy :Non-biologic DMARD therapy is defined as taking a non-biologic DMARD for at least 3months or evidence of intolerance; Apremilast therapy is defined as taking apremilastat the marketed dose approved in the country where the study is being conducted for atleast 4 months or evidence of intolerance; NSAID therapy is defined as taking an NSAIDfor at least 4 weeks or evidence of intolerance
• Participants may have been previously treated with up to 2 anti-TNF (tumor necrosisfactor) alpha agents (approximately 30 percent [%] of the overall study population),and must document the reason for discontinuation

Exclusion Criteria:

• Has other inflammatory diseases that might confound the evaluations of benefit ofguselkumab therapy, including but not limited to rheumatoid arthritis (RA), axialspondyloarthritis (this does not include a primary diagnosis of PsA with spondylitis),systemic lupus erythematosus, or Lyme disease
• Has ever received more than 2 anti-TNFalpha agents
• Has previously received any biologic treatment (other than anti-TNF alpha agents),including, but not limited to ustekinumab, abatacept, secukinumab, tildrakizumab,ixekizumab, brodalumab, risankizumab, or other investigative biologic treatment
• Has previously received any systemic immunosuppressants (for example, azathioprine,cyclosporine, 6 thioguanine, mercaptopurine, mycophenolate mofetil, hydroxyurea,tacrolimus) within 4 weeks of the first administration of study agent
• Has received apremilast within 4 weeks prior to the first administration of studyagent
• Has previously received tofacitinib, baricitinib, filgotinib, peficitinib (ASP015K),decernotinib (VX-509), or any other Janus kinase (JAK) inhibitor