POS0904 FACTORS ASSOCIATED WITH SWITCHING FROM ONE ANTI-TNF AGENT TO ANOTHER ANTI-TNF, OR IL17 AGENT IN PATIENT WITH ANKYLOSING SPONDYLITIS
Authors: Hwang M. , Weisman M. , Gensler L. S. , Tahanan A. , Ishimori M. , Hunter T. , Bolce R. , Lisse J. , Rahbar M. , Shan M. , Reveille J. D. 
Published: May 2021

Background:A recent study examining Commercial Claims Insurance database found that many patients with ankylosing spondylitis (AS) do not remain on their initial TNF inhibitor two years after initiation, particularly women and those taking opioids.Objectives:To examine factors associated with switching from one TNF inhibitor (i)agent to either another TNFi, IL-17i or JAKi over time (at <2years and >2 years) in a longitudinal cohort of AS patients.Methods:Patients enrolled in the Prospective Study of Outcomes in AS (PSOAS), an observational longitudinal study of predictors of AS severity operative since 2002-2020 including over 1250 patients meeting modified New York criteria. Data collected included age, gender, ethnicity, HLA-B27 status, disease activity (BASDAI or ASDAS), erythocyte sedimentation rate (ESR), C-reactive protein (CRP), disease severity,(functional (BASFI) or radiographic (mSASSS)), comorbidities, smoking, exercise, disease duration, depression (either by self report or by the Center for Epidemiologic Studies Depression Scale (CES-D) and other medication usage (NSAIDs, including the NSAID index, nonbiologic DMARDs, opioids, anti-depressants, anxiolytics and hypnotics). Logistic regression models were built to identify clinical and sociodemographic characterstics associated with medication switching to another TNFi, IL-17i, or other biologic therapy (another TNFi, Il-17i, or JAKi) within 2 years and after 2 years of initiation).Results:Of those patients in PSOAS who had at least two years of follow-up, 496 were prescribed anti-TNF, 34 anti-IL-17 and 3 anti-JAK agents. According to the multinomial logistic regression analysis, patients who switched from their original TNFito another TNFi, IL-17i or JAKi within two years after initiating their original TNFi were more likely to be older, have higher baseline subjective disease activity (BASDAI), less radiographic severity by MSASSS, exercise > 120 minutes/week and less likely to be currently smoking. Patients who switched after two years were less likely be depressed, had shorter disease duration, had greater subjective disease activity, were more likely to be exercising > 120 minutes/week, and had more comorbidities.Conclusion:Different factors were encountered in AS patients who switched from their initial TNFi to another TNFi, IL-17i or JAKi within 2 years versus after 2 years of treatment.Table 1.Factors Associated With Switching From One TNFi To A Second TNFi or IL-17i or JAKi Before or After Two Years Based On Multinomial Logistic Regression Model (N=496 Patients)VariableSwitched within 2 years vs. not switchedp-value*Switched after 2 years vs. not switchedp-value*Gender (Male vs. Female)0.99(0.637, 1.549)0.980.95 (0.528, 1.719)0.87HLA-B27_(+ vs. -)0.99 (0.639, 1.523)0.950.66 (0.365, 1.192)0.17Depression (CESD≥ 16 or self-report)(Yes vs. No)0.99 (0.676, 1.445)0.950.35 (0.182, 0.672)0.002Disease duration at baseline (≥20 vs. <20 years)0.72 (0.485, 1.062)0.100.27 (0.146, 0.491)<0.001Age at baseline (≥40 vs. <40) (years)2.00 (1.291, 3.101)0.0021.23 (0.693, 2.193)0.48CRP (≥0.8 vs. <0.8)1.94 (1.230, 3.056)0.0040.90 (0.454, 1.789)0.77BASFI (≥40 vs. <40)1.34 0.852, 2.118)0.200.87 (0.450, 1.688)0.68BASDAI (≥4 vs. <4)1.73 (1.064, 2.797)0.032.31 (1.202, 4.427)0.01NSAID index (≥50 vs. <50)1.32 (0.822, 2.128)0.250.83 (0.437, 1.586)0.58NSAIDs used (Yes vs. No)0.84 (0.534, 1.309)0.430.85 (0.479, 1.510)0.58Exercise (≥120 vs. <120) (minutes/week)1.95 (1.396, 2.731)<0.0011.66(1.057, 2.613)0.03ASDAS (≥3 vs. <3)0.78 (0.454, 1.356)0.391.07 (0.478, 2.399)0.87Number of comorbidities (≥2 vs. <2)1.40 (0.997, 1.951)0.051.63 (1.029, 2.575)0.04mSASSS (≥4, vs. <4)0.63 (0.421, 0.957)0.030.81(0.474, 1.392)0.03Current smoker (Yes vs No)0.69 (0.385, 1.225)<0.0010.79 (0.297, 2.076)0.20*p-values calculated based on multinomial logistic regression model when switching is defined as being prescribed a second TNFi or taking IL-17i or JAKi before or after 2 years from first TNFi initiationDisclosure of Interests:Mark Hwang Consultant of: UCB, Novartis, Michael Weisman Consultant of: Novartis, GSK, UCB, Lilly, Lianne S. Gensler Consultant of: AbbVie, GlaxoSmithKline, Eli Lilly, Novartis, Pfizer, UCB Pharma, Amirali Tahanan: None declared, Mariko Ishimori: None declared, Theresa Hunter Employee of: Eli Lilly, Rebecca Bolce Employee of: Eli Lilly, Jeffrey Lisse Employee of: Eli Lilly, Mohammad Rahbar: None declared, Minyang Shan Employee of: Eli Lilly, John D Reveille Consultant of: UCB, Grant/research support from: Eli Lilly