THU0159 THE ADDITIONAL VALUE OF INTERLEUKIN-6 INHIBITORS ON PATIENT REPORTED OUTCOMES IN THE MANAGEMENT OF RHEUMATOID ARTHRITIS FAILURES TO A PREVIOUS ANTI-TUMOR NECROSIS FACTOR INHIBITOR: RETROSPECTIVE ANALYSIS FROM A LOCAL REGISTRY

Abstract

Background:To date the better strategy for the management of tumor necrosis factor inhibitor (TNFi) failures in rheumatoid arthritis (RA) is still under debate. At the same time, the patient’s perspective is becoming increasingly important in the management of RA and the use of patient reported outcomes (PROs) is becoming more and more frequent in daily practice.Objectives:To evaluate the additional value of PROs in the measure of comparative clinical response in a real-life local cohort of patients treated with different alternative mechanisms of action after the failure of a first-line TNFi.Methods:Data were retrospectively extracted from the registry of the ASST Gaetano Pini-CTO Institute, which include all RA patients treated with biologic drugs between December 1999 and December 2019. The analysis was limited to patients who failed a first-line TNFi and the study population was stratified according to the prescribed second-line mechanism of action (MoA). In each treatment subgroup the 6- and 12-month clinical response was evaluated as the mean change from baseline of Clinical Disease Activity Index (CDAI) score, Patient Global Assessment (PGA), and pain VAS. The rates of patients achieving CDAI remission/low disease activity (LDA) and an acceptable level of pain (pain VAS ≤20) were also calculated. The comparison between treatment subgroups was performed by using the t-test and the Fischer’s test for continuous and dichotomous variables, respectively.Results:A total of 405 patients (192 treated with a second TNFi, 87 with interleukin-6 inhibitors [IL-6is], 70 with abatacept, and 56 with rituximab) were included in the study. In the overall population 352 patients (86.9%) were female, mean (±standard deviation) age was 55.7±13.1 years, mean disease duration 14.3±9.1 years, RF and ACPA were positive in 76.4% and 79.3% of patients, respectively. We observed a clear trend toward the superiority of IL-6is over TNFis in the 12-month mean change from baseline of CDAI score (-13.9 vs -9.2, p=0.06) and in remission/LDA rates (58.7 vs 45.1%; p=0.048). In the evaluation of PROs, we found a statistically significant superiority of IL-6 over TNF inhibitors in the 12-month mean change from baseline of PGA (-34.5 vs -22.6%, p=0.02) and pain VAS (-35.4 vs -19.3%, p=0.01), and a significantly greater rate of acceptable pain level (42.1 vs 25.6%, p=0.01). No significant difference was observed in any of the evaluated items between a second TNFi and abatacept or rituximab.Conclusion:In a RA cohort of real-life insufficient responders to a first TNFi, we observed an overall better clinical response to IL-6is compared to a second TNFi. This effect is much more evident in the measure of PROs rather than composite indices as a possible result of the involvement of IL-6 in the pathways leading to pain and fatigue development in RA.