AB0483 CAN WE PREDICT WHICH PATIENTS WITH SPONDYLOARTHRITIS WILL NEED DOSE ESCALATION OF SECUKINUMAB TO 300 mg MONTHLY?
Authors: D. Fonseca, F. Oliveira Pinheiro, M. Rato, B. M. Fernandes, S. Garcia, A. Martins, D. Santos Oliveira, F. R. Martins, M. Bernardes, L. Costa
Journal: Annals of the Rheumatic Diseases (2021)

Background: Secukinumab is a fully human monoclonal antibody against interleukin-17A, approved in several countries for the treatment of ankylosing spondylitis (AS) and psoriatic arthritis. It is known that some patients benefit from increasing the monthly dose of secukinumab from 150mg, the most commonly used dose, to 300mg. However, the baseline clinical characteristics that differentiate these patients are not yet fully understood. Objectives: This study aimed to investigate whether there are any variables at the beginning of biologic therapy that might predict a greater probability of having to increase the dose of secukinumab to 300mg in order to obtain a response to treatment. Methods: This is a retrospective cohort study, including all the spondyloarthritis and psoriatic arthritis patients under secukinumab at our Rheumatology Department and registered in the national database (Reuma.pt). Demographic, clinical and laboratorial characteristics and disease activity measures were collected from the first visit before the patient began secukinumab. For comparison between the 2 groups, continuous variables were analyzed using Mann-Whitney U and T-tests and categorical variables were analyzed using a Chi-square test. Multivariate regression analyses assessed the impact of selected variables on the need to increase the dose of secukinumab to 300mg. Results: Thirty-two patients with a mean age of 53±11.96 years were included, 19 (58%) were females and 16 (48.5%) had psoriasis. Twenty-seven (81.8%) patients were under a nonsteroidal anti-inflammatory drug (NSAID), 11(33.3%) were under corticosteroid and 11(33.3%) were under conventional synthetic disease-modifying antirheumatic drug (csDMARD); 25 (75,8%) had previously been treated with a biological disease-modifying antirheumatic drug (bDMARD). The mean patient baseline VAS and physician baseline VAS were 74,39±19,77 and 47,55±23,38, respectively; the mean erythrocyte sedimentation rate (ESR) and C-Reactive Protein (CRP) were 26,33±22,62 mm/hr and 10,81±16,88 mg/dL, respectively; the mean swollen joint count (SJC) and tender joint count (TJC) were 1,30±1,63 and 3,67±3,14, respectively; the mean Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Ankylosing Spondylitis Disease Activity Score (ASDAS) were 6,18±2,06 and 3,41±0,84, respectively; the mean Bath Ankylosing Spondylitis Metrological Index (BASMI) and Bath Ankylosing Spondylitis Functional Index (BASFI) were 4,22±1,58 and 6,28±2,53, respectively; the mean Maastrich Ankylosing Spondylitis Enthesitis Score (MASES) was 2,85±3,23. Nineteen patients (57.6%) had the dose of secukinumab increased to 300mg. At the baseline visit, the group of patients which had their secukinumab monthly dose increased to 300mg were more frequently men (12 vs 2, p=0.005) and had psoriasis (12 vs 4, p=0.049). On the other hand, these patients also exhibited lower MASES values (2±1.089 VS 4±0.501, p=0.022). A regression analysis was conducted, estimating the relationships between the outcome binary variable of the monthly dose of secukinumab and the following predictors: gender, psoriasis, MASES value and use of corticosteroid. Female gender (OR 0.070, CI95% 0.005-0.890; p=0.040) and absence of psoriasis (OR 0.104, CI95% 0.011-0.952; p=0.045) were predictors for maintaining secukinumab at a dose of 150mg monthly. Conclusion: Our data suggest that the most common characteristics of patients in need of increasing the monthly dose of secukinumab from 150 to 300 mg to achieve a better treatment response are: male gender, coexistence of psoriasis and lower MASES value at baseline. The first two variables remained statistically significant in a multivariate model of regression analysis. Nonetheless, we insist it is of paramount importance to conduct larger studies to confirm these findings. References: [1]Deodhar A, et all. Long-term safety of secukinumab in patients with moderate-to-severe plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis. Arthritis Res Ther. 2019 May 2;21(1):111. Disclosure of Interests: None declared.