Economic Burden of Switching to Different Biologic Therapies Among Tumor Necrosis Factor Inhibitor-Experienced Patients with Psoriatic Arthritis

INTRODUCTION: Patients with psoriatic arthritis (PsA) who receive an initial tumor necrosis factor inhibitor (TNFi) may switch to another TNFi or a non-TNFi biologic therapy. This study compared the healthcare resource use (HRU), expenditures, and time to discontinuation among TNFi-experienced patients with PsA who switched to different biologic therapies in the United States (US). METHODS: Adults with PsA who discontinued an initial TNFi (adalimumab, etanercept, infliximab, golimumab, or certolizumab pegol) and switched to another TNFi or a non-TNFi (ustekinumab or secukinumab) were identified in the Symphony Health Solutions database [Quarter (Q)1 2010–Q2 2017]. Eligible patients had claims data activity for ≥ 12 months before (baseline) and after (study period) the switching date. All-cause HRU, costs (2017 US dollars), and time to discontinuation during the study period were compared between patients switching to another TNFi vs. a non-TNFi (index drug). Multivariable regression models adjusted for baseline covariates (index year, age, sex, initial TNFi, comorbidities, baseline HRU, and PsA-related treatment history). RESULTS: Of 2107 patients switching to another TNFi and 253 switching to a non-TNFi, adalimumab and etanercept were the most common initial TNFi in both cohorts. During the study period, patients switching to another TNFi had significantly fewer dermatologists visits (0.43; p < 0.01) but more rheumatologist visits (1.56, p < 0.01) than patients switching to a non-TNFi. Patients switching to another TNFi vs. a non-TNFi incurred significantly lower total average healthcare expenditures (adjusted difference: $17,625; p < 0.01), driven by lower prescription drug (adjusted difference: $17,172; p < 0.01) and hospitalization expenditures (adjusted difference: $5772; p = 0.04). Patients who switched to another TNFi vs. a non-TNFi continued on their index therapy significantly longer (median time to discontinuation: 8.31 vs. 5.68 months; log-rank p < 0.01). CONCLUSIONS: Patients with PsA who switched to another TNFi had lower total healthcare expenditures and longer persistence compared with patients who switched to a non-TNFi biologic. FUNDING: AbbVie.