(115) Utilization of Biologics Used for Plaque Psoriasis: A Descriptive Study

Publication Number: 1160

Background: Psoriasis is a common inflammatory skin disorder, and biologics has shown enormous potential. In Denmark, biological treatment is registered both in health registries and in a clinical quality database. These constitute important sources of data for epidemiological research. However, drug utilization patterns of biologics have never been investigated in both data sources simultaneously.

Objectives: The main objective of this study was to describe utilization of biologics for psoriasis in Denmark in the health registries and a clinical quality database Dermbio, separately.

Methods: From two separate nationwide data sources, the health registries and Dermbio, we included all adult psoriasis patients who were registered as first-time users of biologics from 1 January 2011 to 31 December 2018.

Individuals entered the study cohort at their first dispensing of a biologic and were censored at migration, death, end of study period or the first time two or more different substances were dispensed on the same date. Apremilast and the following biologics were investigated: etanercept, infliximab, adalimumab, certolizumab pegol, ustekinumab, secukinumab, brodalumab, ixekizumab, guselkumab, and biological drugs with unspecific coding.

We investigated drug utilization patterns by 1) identifying drugs used in first treatment episodes, 2) describing flow of choice in first, second, third and fourth treatment episodes, 3) investigating drug survival using Kaplan Meier analysis and the proportion of patients covered method.

Results: From 1 January 2011 to 31 December 2018, 1878 patients received biologics according to the health registries and 2264 according to Dermbio. 1593 patients were found in both data sources. Adalimumab was the most common first choice (39% in the health registries vs. 34% in Dermbio), with ustekinumab as the second most common first choice (33% in both data sources). In the flow of choice of biologics, most individuals were observed to have only one treatment episode during the study period according to Dermbio (69%). In the health registries, most individuals were observed to have several treatment episodes during the study period (58%) and of these, 42% had a pause in treatment after the first treatment episode followed by re-initiation with the same drug. Ustekinumab had the longest drug survival (50% still on treatment after 19 months in the health registries vs. 82 months in Dermbio). Among users of adalimumab, 50% were still on treatment after 15 months in the health registries vs. 45 months in Dermbio.

Conclusions: Adalimumab and ustekinumab were the most common first choices, and ustekinumab showed the longest drug survival. There were important differences between the health registries and Dermbio in observed flow of choice and drug survival.