Real-world and long-term data on biologic treatment changes - including switching, discontinuation, dose escalation, and interval change (both increasing and decreasing) - are required to understand treatment patterns for psoriasis (PsO) in Canada. The study objectives were to evaluate the time to first biologic treatment change and to document these changes in Canadian patients with moderate-to-severe chronic plaque PsO. Charts from 13 Canadian sites were queried retrospectively (2005-2019); a period covering all biologic classes commonly used for PsO in Canada. Included were patients diagnosed with, and currently using biologics for, moderate-to-severe chronic plaque PsO. Time to first treatment change, nature of treatment change, number of lines of treatment, proportion of patients on each drug, and drug survival were collected. Based on 1149 medical charts, adalimumab had the longest time to first treatment change (49.3 months; 95% confidence interval, 37.4-67.4). Approximately half of the patients had a treatment change, and nearly 75% of these changes were either an interval change or a biologic switch. Lack of efficacy was the most prevalent primary reason for biologic switch (67.3%), whereas 6.7% of patients switched due to adverse events. Drug survival for etanercept and infliximab was approximately twice as long for patients who had dose optimization (i.e., dose escalation or interval change) than patients without dose optimization. The survival curve of adalimumab was similar to the one of ustekinumab after 48 months of treatment, showing approximately 60% of patients remaining on treatment after 132 months, with or without dose optimization. Assessing treatment patterns of all commonly used biologics for moderate-to-severe chronic plaque PsO in Canada between 2005 and 2019 showed that approximately half of the patients required a treatment change (mainly interval change or biologic switch) while the other half remained on treatment.