Utilization and Adherence Among Infliximab Biosimilar Initiators in a US National Commercial Insurance Database

Real-world national commercial administrative data showed that treatment adherence to infliximab biosimilar is high among patients who were infliximab-naïve, as well as those who had long exposure to infliximab.

At the American College of Rheumatology Convergence 2020 meeting, a report of the utilization pattern and adherence characteristics among patients who initiated infliximab biosimilars across multiple indications using national commercial administrative data was presented.

Patients who received infliximab biosimilars between 2016 and 2017 were identified using procedure and pharmacy codes in the IBM MarketScan database. Eligible patients were classified into 3 cohorts: infliximab biosimilar–naïve users who had never used infliximab; infliximab early switchers, with <2 years of infliximab exposure; and late switchers, with long-term (>2 years) use of infliximab. The medication adherence to infliximab biosimilar was further categorized as <50%, 50% to 80%, and >80%.

A total of 325 patients were identified in the review; of these, 98 patients were infliximab biosimilar–naïve, 114 patients were early switchers, and 113 patients were late switchers. Compared with the 2 patient subgroups that switched, patients in the infliximab biosimilar–naïve group were younger and more likely to be female. The primary autoimmune disease diagnosis was inflammatory bowel disease (40.9%-45.4%), followed by rheumatoid arthritis (15.4%-29.6%) and psoriasis (9.7%-13.9%). Of the patients who had ≥12 months of follow-up, adherence to biosimilars was >80% at 12 months, with 53.6% of patients in the naïve-users group, 44.3% patients in the early switchers group, and 56.1% of the late switchers group showing adherence.

These results indicate that about half the patients who initiated infliximab biosimilar, as well as patients who switched to biosimilar after >2 years of infliximab use, showed >80% adherence at 12 months; further studies are warranted to determine long-term adherence.

Reference
Sarvesh S, et al. Arthritis Rheumatol. 2020;72(suppl 10):Abstract 555.