Background Patients with difficult-to-treat rheumatoid arthritis (D2T RA) have not achieved treatment target despite treatment according to EULAR recommendations. Information on the incidence rates of D2T RA in a real-life setting is lacking. Objectives To estimate the prevalence of D2T RA in a well-characterized cohort. Methods This was a cross-sectional analytical study of patients with RA (1987 ACR criteria). Each patient was evaluated and followed by a rheumatologist from January 2014 to December 2021 in a single rheumatology outpatient private center in Bogotá, Colombia. RA patients were classified as D2T RA according to EULAR definition. Results A total of 783 patients were evaluated. Baseline characteristics were as follows: female gender 91.1%, mean age 54.4±13 years, mean disease duration 13.9±9.3 months, RF positive 92.4%, ACPA positive 59.5%, and erosions 44.3%. 32.9% have extra-articular manifestations and 31.6% at least one comorbidity. Most of patients have received conventional synthetic DMARDs (97.8%), being prednisone and methotrexate the most frequently prescribed. Seventy-nine (10%) patients were classified as D2T RA. The current treatments were conventional synthetic DMARD alone 18.9%, combination with bDMARD 79.4%, and 78.5 with glucocorticoids. Main characteristics of the patients are shown in Table 1. Table 1. D2T RA (n=79 ) Demographics Age, years 54.4 Female, % 91.1 Comorbidity 31.6 Smoking 37.9 Disease characteristics Disease duration, months 13.9 RF positivity, % 92.4 ACPA positivity, % 59.5 PAI 10.1 EAM 32.9 Drugs Number of previous bDMARDs, mean 2.89 Glucocorticoid therapy, mean dose per day (mg) 18.4 RF: rheumatoid factor; ACPA:anti-citrulinated protein antibodies; PAI: poliautoimmunity, EAM: extra-articular manifestations, bDMARD: disease-modifying biologic antirheumatic drug; D2T: difficult-to-treat; n: number; mg miligrams Conclusion D2T AR is common and represents a phenotype with a significant burden of comorbidities and a high prevalence of poor prognostic factors. This concept should be recognized and taken into account to bring a personalized approach. References [1]Nagy G, Roodenrijs NMT, Welsing PMJ, et al. Ann Rheum Dis 2021;80:31–35. [2]Takanashi S, et al. Characteristics of patients with difficult-to-treat rheumatoid arthritis in clinical practice. Rheumatology (Oxford). 2021;60(11):5247-5256 [3]Roodenrijs NMT, et al. Difficult-to-treat rheumatoid arthritis: contributing factors and burden of disease. Rheumatology (Oxford). 2021;60(8):3778-3788. Disclosure of Interests None declared