Background: Psoriatic Arthritis (PsA) is a chronic inflammatory disease that substantially impact patients’ quality of life. Despite advances in biologic treatments, up to 40% of patients exhibit partial or poor responses. There remains an urgent and unmet need for predictive tools to personalize biologic selection and improve disease management. Objectives: To identify predictive biomarkers of treatment response to biologic agents in patients with PsA. Methods: A total of 19 patients with PsA who were treated with at least one biologic agent were included in this study. Peripheral Blood Mononuclear Cells (PBMCs) were collected, stimulated with Streptococcus pyogenes, then treated with various biologic agents in vitro. Cytokine levels were quantified through a multiplex immunoassay before and after biologic treatment. Clinical disease activity was evaluated in terms of tender joint count, swollen joint count, and Disease Activity In Psa (DAPSA) scores before and after biologic treatment. Spearman’s rho was used to analyze the correlations between cytokine level and clinical improvement. Results: Levels of IFN-?, MCP-1 and RANTES (CCL5) after biologic treatment were significantly associated with an improvement in DAPSA scores (p = 0.012, p = 0.047, and p = 0.003, respectively). However, no significant associations were observed for the other cytokines. Conclusion: IFN-?, MCP-1 and RANTES may serve as reliable predictive biomarkers of clinical response to biologic agents in patients with PsA. Establishing a predictive model combining PBMC testing with cytokine profiling may represent a novel personalized approach for selecting optimal biologic treatments.