Ustekinumab is the most recently approved biologic for the treatment of moderate-to-severe psoriasis. Real-world dosing patterns of ustekinumab are yet to be fully characterized.A retrospective, observational study was conducted using MarketScan Commercial and Medicare databases. A cohort of psoriasis patients treated with ustekinumab between 25 September 2009 and 31 October 2010 was evaluated. Main outcomes included ustekinumab dosing and treatment patterns. Kaplan-Meier estimates were calculated to adjust for the censoring of data. Subgroup analysis was conducted for biologic-experienced patients and biologic-naïve patients.One thousand ustekinumab patients were included, of whom 60% were biologic-experienced. The average age was 49.0 and 53.9% were male. 63.3% of patients initiated ustekinumab with a 45 mg dose and 34.5% initiated with a 90 mg dose. Mean (median) days from initial dose to second dose was 31.1 (28.0). During maintenance therapy, dose intervals spanned from 80.6 to 81.2 (84.0) days. About 81.4% of patients were persistent during the variable-length follow-up period.The majority of patients received the 45 mg ustekinumab dose. The mean dosing intervals were consistent with the US prescribing guidelines. Biologic-naïve and biologic-experienced patients had similar dosing patterns. Ustekinumab treatment achieved a persistency rate as high as 81.4% over an average of 186.5 (SD 114.2) days of follow-up.