Background:Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease that without treatment causes disability, pain, quality of life impairment, and premature mortality. It causes significant economic repercussions on patients, their families, and the health system. The costs of RA for Sanitary Systems are described in terms of medications and hospitalization. Also, the cost of treatment for patients whose disease was not adequately controlled from an early stage may involve joint replacement surgery and prolonged hospitalizations.Objectives:To determine and analyze the cost-effectiveness of the clinical approach to rheumatoid arthritis in a cohort of patients in the early phase versus a cohort of patients in the established phase from a fourth-level Health Service Provider Institution in Colombia, from the perspective of the third-party payer with a time horizon of six-months.Methods:An economic evaluation of the cost-effectiveness of the clinical approach was carried out in the early phase versus the established phase in a cohort of patients from May 2013 until December 2018, with rheumatoid arthritis from a fourth-level Health Service Provider Institution in Colombia, from the perspective of the third-party payer with a time horizon of six-months. The costs and effectiveness of each of the phases were estimated. A decision tree model was created, and the incremental cost-effectiveness ratio was calculated. The deterministic and probabilistic sensitivity analysis was performed.Results:The early phase clinical approach for patients with rheumatoid arthritis represents savings of approximately 600 USD per patient in remission or low disease activity level in the first 6 months of follow-up from the perspective of the third-party payer.Conclusion:The clinical approach to rheumatoid arthritis in the early phase is a less costly and more effective alternative versus established phase and generates savings for the third-party payer with a time horizon of six-months.Figure 1.Acceptability curveDisclosure of Interests:None declared