Healthcare Cost and Utilization Associated with Biologic Treatment Patterns Among Patients with Psoriatic Arthritis: Analyses from a Large US Claims Database

BACKGROUND: Costs associated with biologic switching and discontinuation can be high in psoriatic arthritis (PsA), and their inappropriate use may have cost implications for patients, healthcare professionals, and payers. OBJECTIVE: To compare direct costs of treatment switchers, non-switchers, and discontinuers among patients with PsA who newly initiated a biologic. METHODS: Patients with PsA aged ≥ 18 years with ≥ 1 pharmacy claim for an FDA-approved subcutaneous biologic from 1 January 2016 to 31 December 2016 were identified from the Truven Health MarketScan Databases. Patients were categorized into three mutually exclusive groups of non-switchers, switchers, and discontinuers, and healthcare costs and utilization during 1-year follow-up were described across the three groups separately. RESULTS: A total of 2560 patients with PsA newly initiating a biologic were categorized as non-switchers (54.8%), switchers (18.5%), and discontinuers (26.7%). During 1-year follow-up, after adjusting for age, sex, full-time work status, and co-morbidities, switchers had higher mean total all-cause healthcare costs than non-switchers (US$80,380 vs. US$69,031), driven by increased pharmacy (US$66,531 vs. US$56,674) and outpatient (US$10,881 vs. US$8,235) costs (all P < 0.0001). Discontinuers had the lowest mean total all-cause healthcare costs (US$50,054) but the highest medical costs (US$20,323). Switchers and discontinuers had higher all-cause healthcare utilization than non-switchers during 1-year follow-up, except switchers had fewer hospitalizations. CONCLUSIONS: Patients with PsA who switch or discontinue biologics have higher medical costs and healthcare utilization than those continuing the same biologic. These findings highlight that discontinuing or switching biologic therapies is associated with higher costs in patients with PsA, which may inform treatment and/or formulary decision-making.