Review of the reasons for and effectiveness of switching biologics for psoriasis treatment in Korea

Background: Switching of biologics in patients has become common in clinical practice. Objectives: This study investigated the reasons for and effectiveness of switching biologic agents during the treatment of psoriasis. Methods: We retrospectively reviewed patients with psoriasis who were treated with biologics at Pusan National University Hospital and Chosun University Hospital from March 2012 to June 2020. We assessed their demographics and treatment characteristics (reasons for switching biologics and efficacy of the first- and second biologic agents). Results: Of the 162 psoriatic patients treated with biologic agents for more than 52 weeks, 35 required a switch to another biologic agent. The reasons for switching biologic agents were inefficacy (n = 30), adverse events (n = 2) and others (n = 3). The mean psoriasis area and severity index (PASI) score was 12.1 at the start of the second biologic and 3.4 at 14-16 weeks later. Patients were more likely to switch to another biologic agent when they exhibited a high initial psoriasis area and severity index score and concomitant psoriatic arthritis. Limitations: As a retrospective study, there were some limitations such as lack of a placebo control group and the time point of 14-16 weeks being somewhat early to judge the effect of the biologics. Conclusions: The most common reason for switching biologic agents in Korea was treatment inefficacy, especially secondary failure. Despite the inefficacy of previous biologic agents, switching to a different agent may be an efficacious approach.