OBJECTIVES : In 2016, infliximab, was the first anti-inflammatory (AI) biologic to have an FDA-approved biosimilar. Since then, two additional infliximab, five adalimumab, two etanercept, and two rituximab biosimilars have been approved; however, only three AI biosimilars (two infliximab, one rituximab) are available in the US at the time of this analysis. This study evaluated product use patterns in patients treated with AIs observed in insurance claims, and prepare for real-world, observational comparative effectiveness studies using the Biologics & Biosimilars Collective Intelligence Consortium (BBCIC) distributed research network (DRN).

METHODS : Adults treated with AIs from 1/1/2012 to 3/31/2019 were included. A distributed query using FDA Sentinel analytic tools captured characteristics of patients receiving biologic AI treatment. Data were aggregated from five health plan partners in the BBCIC DRN.

RESULTS : Over 30 million eligible health plan members representing over 75 million person-years of data were evaluated. Adalimumab was the most common anti-TNF product with 41,757 (44.8%) of all anti-TNF incident users, followed by etanercept (22.0%) and infliximab products (16.8%). A total of 651 incident users of the biosimilar infliximab-dyyb (4.2% of all infliximab use), and 39 new users (0.2%) of infliximab-abda were observed. Rituximab was the most common non-TNF product with 29,032 (46.1%) of all incident non-TNF users, followed by ustekinumab (15.8%) and abatacept (12.0%). The proportion of rituximab users declined from 64.7% of all non-TNF use in 2012 to 37.9% in 2017, while use of newer products including vedolizumab and secukinumab have gradually increased to 9.6% and 12.9%, respectively, by 2017.

CONCLUSIONS : This systematic, longitudinal surveillance highlighted trends in AI use patterns in the US. Biosimilar use has steadily grown. With multiple biosimilars and new innovator products becoming available we expect the market shares will continue to shift. This is important information to inform future research in AIs in the BBCIC DRN.