Driving Biosimilar Uptake in Rheumatology, Biosimilar-to-Biosimilar Switching: ACR Abstracts

The initial uptake of biosimilars in the rheumatology space has been slow with only 6 on the market in the United States; however, institutions can drive use of biosimilars through changes in the electronic health record (EHR), according to an abstract presented at ACR Convergence 2022, the annual meeting of the American College of Rheumatology.¹

At the authors’ academic medical center, biosimilars were not only made available to order within the EHR, but they were eventually made the default orders. Within the EHR, biosimilars replaced originator drug orders. The researchers measured the impact of these changes on the use of biosimilars using data of patients with rheumatic diseases receiving either infliximab or rituximab between August 2018 and March 2022.

There were 1270 orders for originator infliximab, 129 orders for infliximab biosimilars, 1295 orders for originator rituximab, and 208 orders for rituximab biosimilars from 16 rheumatology providers. The infliximab orders were tracked from August 2018 to March 2022; the rituximab orders were tracked between February 2020 and March 2022.

The researchers found that the monthly percentage use of infliximab biosimilars was initially 4.06% after the first biosimilar was introduced, but that declined to 1.87% in November 2019 after it was added as an option in the EHR.

For both rituximab and infliximab biosimilars, the percentage use increased significantly after the biosimilar was made the default order in the EHR:

• Monthly average use of infliximab increased to 19.13% in February 2020
• Monthly average use of rituximab increased to 31.84% in December 2020

“In our institution, a significant increase in uptake was not seen until the biosimilar drug was made the default EHR order, replacing the originator drug,” the authors concluded. “With an estimated cost that can be up to 40-50% less than the originator drugs, we estimate that the continued increase in biosimilars uptake will lead to significant savings.”

Another abstract presented at ACR Convergence 2022 reviewed biosimilar-to-biosimilar infliximab switching using the DANBIO registry.² This type of nonmedical switching happens for the purposes of saving costs, usually. While there are many studies highlighting the safety and efficacy of switching from originator products to biosimilars, there is less research on switching among biosimilars.

The study investigated the effectiveness of switching from CT-P13 to GP1111 among patients in Denmark with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (AxSpA). The patients included those who had switched from the originator initially (originator-experienced) and those who had never been on the originator (originator-naïve).

A total of 1605 patients were included: 685 patients with RA, 314 with PsA, and 606 with AxSpA. The median disease duration was 9 years. The majority of patients (72.9%) were considered originator naïve.

At 1 year, 83% of originator-naïve patients (95% CI, 81%-85%) and 92% of originator-experienced patients (95% CI, 90%-95%) remained on GP1111. After the switch, changes in disease activity were close to zero for all measures included, such as Disease Activity Score-28 and Ankylosing Spondylitis Disease Activity Score.

In addition to originator-experienced patients having higher retention rates, so did patients with RA and PsA compared with AxSpA, as well as patients with a lower disease activity at baseline.

According to the authors, the higher retention rates among originator-experienced patients and those with low disease activity suggest “outcomes to be affected by patient- rather than drug-related factors.”

References

1. Eseddi J, Carmichael D, Wishin S, Bajaj P. Increasing biosimilar uptake in the rheumatology clinics within a large academic medical center. Presented at: ACR Convergence 2022; November 10-14, 2022; Philadelphia, PA. Abstract 1286.

2. Nabi H, Hendricks O, Vendelbo D, et al. Biosimilar-to-biosimilar switching in routine care – results on >1,600 patients with inflammatory arthritis in the DANBIO registry. Presented at: ACR Convergence 2022; November 10-14, 2022; Philadelphia, PA. Abstract 1112.