OBJECTIVES: To describe health care costs associated with the management of PsA in patients newly initiated on a biologic DMARD or MTX. METHODS: Adult patients with ≥2 PsA diagnosis (from office visits), continuously enrolled ≥6-month pre- and ≥12-month post-index date (i.e., first biologic DMARD/MTX prescription date), and no diagnosis for ankylosing spondylitis were selected from the MarketScan Commercial Claims database (2005-2009). MTX initiators were required to be both biologic and non-biologic DMARD naïve prior to index date. Biologic initiators were required to be biologic-naïve only prior to index date. All-cause and PsA-related total healthcare costs were estimated during the 12-month study period from a payer perspective (2011 USD). PsA-related medical cost was defined as costs associated with a claim with a PsA diagnosis or with DMARD administration by healthcare professionals. Office care and monitoring costs were defined as the sum of PsA-related outpatient and other medical services costs (excluding costs for drugs administration). Urgent care costs were defined as the sum of inpatient and emergency room costs. PsA-related pharmacy costs were defined as the sum of biologic and non-biologic DMARD costs. RESULTS: A total of 1,217 MTX initiators and 3,263 biologic initiators met the eligibility criteria. MTX initiators had an average annual total healthcare cost of $14,329 where $6,065 were PsA-related. Pharmacy costs accounted for 80.4% of total PsA-related costs; office care and monitoring costs for 16.3%; urgent care costs for 3.3%. Biologic initiators had an average annual total healthcare cost of $30,282 and 67.5% were PsA-related. Pharmacy costs accounted for 92.7% of PsA-related total costs; office care and monitoring cost for 5.1%; urgent care cost for 2.3%. CONCLUSIONS: PsA patients initiating a DMARD incurred substantial healthcare costs. Although pharmacy costs accounted for most of the PsA-related costs, office care and monitoring costs represented a significant part of the PsA-related costs.