Guselkumab vs Golimumab for Psoriatic Arthritis

Inclusion Criteria: 1. Psoriatic arthritis meeting CASPAR criteria; 2. Active psoriatic arthritis defined by at least 1 swollen joint; 3. cDAPSA score ≥ 10; See also Exclusion #4 - cDAPSA must be \> 14 in patients without psoriasis. 4. Using a TNFi or previously used a single TNFi historically and either never responded or lost response (TNF IR) and planning to switch to a new biologic therapy; 5. If using an oral small molecule/csDMARD (i.e., methotrexate, leflunomide, hydroxychloroquine, sulfasalazine, or apremilast), must be on a stable dose for 4 weeks and remain on a stable dose during the study; Use of up to two OSM/csDMARDs is allowed. 6. If using NSAIDs, glucocorticoids (\<10 mg daily) or topical medications for psoriasis, must be on a stable dose for 4 weeks prior to Screening/Baseline 1 and remain on a stable dose during the study; 7. Age 18-80 (patients older than 80 may be more likely to have concomitant osteoarthritis which may make it difficult to assess whether symptoms are related to PsA vs OA). Exclusion Criteria: 1. Prior exposure to golimumab or another non-TNFi biologic (IL12/23i, JAKi, an IL17i, or an IL23i); prior exposure to a TYK2i is acceptable, but cannot be used during course of the study; 2. An adverse event that precludes use of another TNFi (development of drug-induced SLE, allergic reaction, serious infection, heart failure symptoms, demyelination at any point during use of therapy) or any other contraindication or substantial intolerance to a TNFi; 3. Use of moderate to high dose glucocorticoids (\>10 mg); 4. Already meets the primary endpoint at Baseline; \[cDAPSA low disease activity ≤ 14; IGA of psoriasis 0/1\] In patients with psoriasis, cDAPSA can be 10-14 IF the Investigator Global Assessment of Psoriasis ≥ 2. In patients without psoriasis, cDAPSA must be \> 14 to meet eligibility requirements. 5. Currently pregnant or actively trying to conceive.