A Study to Evaluate the Efficacy and Safety of JNJ-88545223 for the Treatment of Participants With Active Psoriatic Arthritis

Inclusion Criteria:

• Have a diagnosis of psoriatic arthritis (PsA) for at least 3 months before the firstadministration of study intervention and meet classification criteria for PsoriaticArthritis (CASPAR) at screening

• Have active PsA as defined by: (a) At least 3 swollen joints and at least 3 tenderjoints at screening and at baseline (Week 0/Day 1) based on the 66/68 jointassessment; AND (b) C-reactive protein (CRP) greater than or equal to (>=) 0.1milligrams per deciliter (mg/dL) at screening from the central laboratory

• Have >= 1 of the following PsA subsets: distal interphalangeal joint involvement,polyarticular arthritis with absence of rheumatoid nodules, asymmetric peripheralarthritis, 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

• A female participant of childbearing potential must have a negative highly sensitiveserum pregnancy test (Beta-hCG) at screening and a negative urine pregnancy test atWeek 0 prior to administration of study intervention

Exclusion Criteria:

• Has a nonplaque form of psoriasis (for example, erythrodermic, guttate, or pustular)

• Has a history or current signs or symptoms of severe, progressive, or uncontrolledrenal, hepatic, cardiac, vascular, pulmonary, gastrointestinal, endocrine,neurologic, hematologic, rheumatologic (except PsA), psychiatric, genitourinary, ormetabolic disturbances

• Has suspected or known allergies, hypersensitivity, or intolerance to JNJ-88545223or excipients used in the investigational medicinal product (IMP), including placebo (JNJ-88545223 investigator's brochure); or has a history of severe allergicreaction, angioedema, or anaphylaxis to drugs or food

• Has fibromyalgia or osteoarthritis symptoms that, in the opinion of theinvestigator, would have potential to interfere with efficacy assessments

• Currently has a malignancy or has a history of malignancy within 5 years prior toscreening