Real-world utilization data indicate that treatment outcomes with infliximab biosimilars were similar to those with reference infliximab in patients with rheumatoid arthritis.
Real-world utilization and characteristics of patients receiving reference infliximab and its biosimilars for the treatment of rheumatoid arthritis (RA) at US community rheumatology practices were reported at the American College of Rheumatology Convergence 2020 meeting.
A retrospective review of electronic medical records identified patients with RA diagnosis who initiated or switched to infliximab or its biosimilars since December 2016 at the American Rheumatology Network (ARN) – Trio Health Rheumatology registry, one of the largest independent practices in the United States, with 200 practicing rheumatologists.
A total of 3156 patients received infliximab or its biosimilars. Of these, 1972 (62%) patients received reference infliximab and 1184 (38%) patients received infliximab biosimilars. Patients who switched between different biosimilars or infliximab were not included in the analysis (n = 350). Of the 834 eligible patients treated with biosimilars, 574 patients were treated with infliximab-dyyb and 260 patients with infliximab-abda.
Some differences in demographic and baseline clinical characteristics were noted between the infliximab and biosimilar groups. Although age and gender profiles were similar among the infliximab, infliximab-dyyb, and infliximab-abda groups, patients in the biosimilars group were less likely to have commercial insurance and more likely to be on Medicaid compared with the infliximab group. Compared with the biosimilars group, patients in the infliximab group had longer follow-up, fewer prior disease-modifying antirheumatic drugs or biologic regimens, higher use of methotrexate or steroids, and longer duration of treatment with infliximab compared with the biosimilars group. Infliximab was used earlier in the treatment journey than biosimilars, with a higher proportion of patients in remission at baseline.
Compared with the biosimilars group, patients in the infliximab group were more likely to be in remission/low disease activity at treatment initiation and at 6 months since treatment initiation. Remission/low disease activity outcomes were similar between the infliximab-dyyb and infliximab-abda groups. The median time to treatment discontinuation was not statistically different among groups (12.0 months for infliximab, 10.4 months for infliximab-dyyb, and median time not reached for infliximab-abda).
Treatment with infliximab or its biosimilars was not significantly associated with treatment success at 6 months since regimen initiation, after accounting for patient (age, payer) and treatment (regimen, steroid use, treatment duration, number of prior regimens, and baseline disease activity status) characteristics; baseline disease activity, regimen duration, and use of steroids were found to significantly impact treatment outcome.
These real-world data indicate that treatment outcomes with infliximab biosimilars were similar to those with reference infliximab in patients with RA.
Reference
Helfgott S, et al. Arthritis Rheumatol. 2020;72(suppl 10):Abstract 812.