Background:As structural damage is irreversible and strongly associated with functional disability1, it is an important outcome to be prevented in rheumatoid arthritis (RA). Acute phase markers, rheumatoid factor (RF) and anti-citrullinated protein (anti-CCP) positivity are important predictors of erosive disease2. Previous studies conducted in real life setting have divergent results regarding the role of disease activity in radiographic progression3,4.Objectives:To evaluate the impact of disease activity and biologic disease modifying anti-rheumatic drugs (bDMARDs) on radiographic progression of established RA in clinical practice in southern Brazilian public health system.Methods:Longitudinal retrospective study including patients with RA (1987 ACR criteria) treated with bDMARDs and followed from 2015 to 2019. Clinical and demographic data were collected at baseline. Radiographs of hands and feet were performed yearly. X-rays were scored according to the van der Heijde-modified total Sharp method (vdH-mTSS) in known chronological order. Clinical relevant radiographic progression (CRRP) was defined as an increase ≥3 units on the score per year5.Demographic, clinical, and radiographic characteristics of RA patients with or without relevant progression were compared with Fisher exact and Mann-Whitney test.Results:Seventy-five patients were included. The patients’ characteristics are shown in table 1. Twenty three (30%) patients presented CRRP at any time point of the follow up (figure 1). Mean DAS28-ESR at baseline was higher in patients who progressed radiographically, than those who did not progress (4.8±1.1 vs 3.5±1.1; p < 0.001). No patient in remission at baseline presented with CRRP. Radiographic progression occurred in 15% of patients in low disease activity, 34% of patients in moderate disease activity and 57% of patients in high disease activity at baseline, depicting a linear relation between categories of disease activity and CRRP. RF, anti-CCP, disease duration, educational level, smoking status, total vdH-mTSS at baseline, number and duration of biologic DMARDs were not associated with CRRP. No single biologic DMARD was associated with worse radiological prognosis.Table 1.Baseline characteristics and bDMARD treatment during 5 years of follow upCharacteristicsN = 75Age, yrs, mean ± SD58.1 ± 10.1Female, n (%)65 (86.6)Disease duration, yrs, mean ± SD16.2 ± 7.6IgM RF positivity, n (%)69 (92)Anti-CCP positivity, n (%)27 (75) *DAS28-ESR, mean ± SD4.2 ± 1.0Educational level, n(%) Elementary school (≤ 8years)49 (65) Intermediate school (9-12 years)23 (30,6) University/college degree3 (4)SmokingCurrent or former31 (41.3)Never44 (58,7)vdH-mTSS, median (IQR)21 (5-53)Number of bDMARD, mean ± SD2.4 ± 1.1Duration of bDMARD, yrs, mean ± SD7.4 ± 2.6Methotrexate use, n, %61 (81)Biologic DMARD184**TNF inhibitors, n, %106 (57.6)Tocilizumab, n, %30 (16.3)Abatacept, n, %25 (13.6)Rituximab, n, %23 (12.5)RF rheumatoid fator anti-CCP anti-citrullinated protein bDMARD biologic disease-modifying anti-rheumatic drug ESR erythrocyte sedimentation rate DAS28 disease activity in 28 joints vdH-mTSS van der Heijde-modified total Sharp score IQR interquartile range *information available from 36 patients **all bDMARD treatmentsConclusion:In contrast to controlled clinical trials, real-world studies have shown that patients with RA treated with bDMARD still develop radiological progression. We observed that despite prognostic factors, achievement of treatment target is the most important factor to prevent articular damage in RA.