FRI0080 SURVIVAL ON SECOND-LINE BIOLOGIC THERAPY AFTER THE WITHDRAWAL OF AN ANTI-TNF TREATMENT IN PATIENTS WITH RHEUMATOID ARTHRITIS: EXPERIENCE IN A SPANISH TERTIARY HOSPITAL

Abstract

Background: Patients with Rheumatoid Arthritis (RA) have been traditionally treated with other TNF inhibitors (TNFis) after the withdrawal of a first TNFi (cycling). However, due to the increase in the biological therapy options, changing to a biologic agent with different mechanism of action (switching) is an alternative choice. More studies are needed to clarify the role of both strategies in order to guide treatment decisions. Objectives: To analyze the survival of the second biological drug, TNFi or biologic with a different mechanism of action, in patients with RA non-responders to the first TNFi. To evaluate factors associated with the survival of the second-line therapy. Methods: A retrospective, longitudinal, observational study was performed, which included patients diagnosed of RA and treated with biological therapies between 2008 and 2017, who discontinue a first-line TNFi and started a second-line biological therapy. The demographic and clinical data were obtained from their medical records. Kaplan Meier and Log-rank survival analysis were performed, as well as Cox regression to identify related factors. Results: 69 patients were identified, 14 men (20.3%) with a mean age at the beginning of the treatment of 52.68 ± 19.79 years. Demographic and clinical data are shown in the table. The main cause of withdrawal of the first TNFi was secondary failure (47.8%), followed by side effects (34.8%) and primary failure (13%). Cycling was performed in 34 patients (49.3%) and switching in 35 (50.7%). During the follow-up, the main causes of withdrawal of the second-line treatment were primary and secondary failure (10.1% in both cases). The survival analysis of the 42 patients who presented a primary or secondary failure to the first TNFi was stratified according to the cause of withdrawal of the second biological therapy. When cycling was chosen, the average treatment survival was 8.8 months (CI95%:4.8-12.8) whereas for the switching option it was 23 months (CI95%:5.4-40.5), being the differences statistically significant (p=0.049). Age was shown as a protective factor (HR=0.86, CI95%:0.76-98) and the positivity of Rheumatoid Factor (RF) as a risk factor (HR=4.76, CI95%:1.39-16.30) for the withdrawal of the second biological therapy. No differences were found in the withdrawal rate due to adverse effects among patients who performed switching or cycling (11.42% vs 5.88%, p=0.41). Conclusion: Switching strategy showed a greater drug survival time and was considered as a better option after the failure of a first TNFi. RF positivity was associated with an increased risk for the withdrawal of the second-line biological therapy. Reference: [1] Todoerti M, Favalli E, Iannone F, Olivieri I, Benucci M, Cauli A, Mathieu A, Santo L, Minisola G, Lapadula G, Bucci R, Gremese E, Caporali R. Switch or swap strategy in rheumatoid arthritis patients failing TNF inhibitors? Results of a modified Italian Expert Consensus. Rheumatology. 2018; 57: vii42–vii53 Disclosure of Interests: None declared