OBJECTIVES: To describe biologic treatment patterns and effectiveness among patients with psoriasis who initiated biologic therapy in dermatology clinics in England. METHODS: A chart review was conducted using a sequential cohort of 169 patients with psoriasis ≥18 years of age from six dermatology clinics. Data were abstracted for patients newly initiating biologic treatment between 1 July 2005 and 30 June 2009. Severity was measured by the Psoriasis Area and Severity Index (PASI, range: 0 to 72) at baseline and time of treatment change. Higher scores indicated increased severity (score >10 indicates moderate to severe disease); adequate response was defined by a ≥75% reduction. Biologic treatment patterns in the first 12 months following initiation (discontinuation, switching, dose increase, and persistence), including reason for treatment change, were collected. RESULTS: Average age at biologic initiation was 49 years, 59.5% were male, with mean disease duration of 15 years. Mean (SD) PASI score at initiation was 18.4 (7.8). Eighteen percent of patients discontinued biologic use, 12% switched, and 7% increased their biologic dose within the first 12 months.  Patients who persisted on initial biologic therapy (63%) achieved an average PASI score of 3.9 (78% improvement) at 12 months. When lack of effectiveness was cited at time of discontinuation, the mean PASI score was 22.6 (43% increase). Among patients who switched, the mean PASI was 15.7 (24% reduction) at the time of switch.  In those who increased their dose, mean PASI score was 9.4 (52% reduction) at the time of dose increase. CONCLUSIONS: A large proportion (37%) of patients changed or discontinued biologic therapy due to an inadequate response to initial treatment within the first year.  These patients experienced limited PASI response and PASI scores were found to be high at time of treatment change, suggesting an unmet need exists for this population.