OBJECTIVES: Adalimumab-afzb (PF-06410293, “ADL-afzb”) has been approved as an adalimumab biosimilar in Canada since 2021 and it is important to gather additional post registration real-world data. The goal of this study was to describe the experience of patients on ADL-afzb, including demographics, previous biologic use, adherence and persistence. Results were compared to the reference adalimumab (D2E7, “ADL-Ref”) and other adalimumab biosimilars (ABP501, SB5, FKB327, GP2017, MSB11022, AVT02 and CT-P17)

METHODS: This retrospective cohort study utilized longitudinal claims data from IQVIA Canada’s Private Drug Plan and Ontario Drug Benefit databases. Patients initiating adalimumab from March 1, 2022 to October 21, 2022 were indexed in analysis groups based on their first claim (1- ADL-afzb, 2-ADL-Ref, 3-Other adalimumab biosimilars) and were followed for 6 months. Log-rank test and Kaplan-Meier curves were used to assess persistence, while adherence was estimated using proportion of days covered (PDC).

RESULTS: 5,874 patients were included; with 657 indexed on ADL-afzb, 693 on ADL-Ref and 4,524 on other adalimumab biosimilars. The average patient age was 47 for ADL-afzb, 49 for ADL-Ref and 51 for other adalimumab biosimilars. Patients were mostly female for all groups (52-56%). Biologic experience (other than adalimumab) was 12% in ADL-afzb, 12% in ADL-Ref and 14% in other adalimumab biosimilars. 71% of ADL-afzb, 1% of ADL-Ref and 53% other adalimumab biosimilars patients were adalimumab-experienced. Persistence at 6 months was not significantly different between ADL-afzb (81%) and other adalimumab biosimilars (77%) (p-value=0.6, adjusted relative to 0.05 using Sidak's method for three comparisons), but lower for ADL-Ref (63%). The proportion of adherent patients (≥80% PDC) was 77% for ADL-afzb, 74% for ADL-Ref and 78% for other adalimumab biosimilars.

CONCLUSIONS: Our findings suggest high persistence and adherence rates for patients receiving adalimumab-afzb in a real-world setting. Further studies are needed to determine the persistence and adherence of adalimumab biosimilars over an extended duration.