The Influence of an Infliximab Biosimilar on Hospital Savings

Image Credit: Adobe Stock Images/Carl.com

Biosimilars—biologic drugs that are biologically similar to their reference products—are often hailed for their potential to offset the high cost of this drug class. They are marketed at purchase prices that are 10% to 40% lower than the cost of the originator, once the originator’s patent expires of course.¹

The biologic drugs themselves are made up of complex molecules developed by biotechnology, and have improved the management of conditions such as diabetes, helped provide additional oncology treatment options, and furthered the development of autoimmune disease therapeutics.

While many clinicians have expressed comfort with the use of biosimilars in “biologic-naïve” patients—those who have not previously received treatment with this class of drug—there has been some push back from the industry, due to the chance that switching patients who are already stable on the originator could cause adverse effects and impact management of their condition. Switching for these reasons is often known as non-medical switching (NMS), but the validity of these statements requires further data.

A study published in Health Economics Review¹ sought to determine the difference in inpatient and outpatient costs, along with the length of stay among patients who originally took CT-P13, an infliximab biosimilar, or switched from original infliximab (OI), who stopped treatment or who continued to take the same biologic.

One hundred and fourteen gastroenterology, 60 immunoallergology, and 84 rheumatology patients who received care between September 2017 and December 2020 at a university hospital in Western Switzerland were included in this retrospective cohort study. They were split up into seven cohorts, whose classifications were based on their treatment pathway (including use and discontinuation of CT-P13 and/or originator infliximab).

Costs were gathered from the hospital's cost accounting department, while impatient records revealed length of stay. Comparisons of costs and length of stay between cohorts were calculated with the use of bootstrapping.

On average, inpatient and outpatient costs averaged (standard deviation) approximately $1,774 (1,020) per hospital day and $5,495 (6,931) per infusion, respectively. The mean (standard deviation) length of stay was 20 (28) days. Of course, the data demonstrates that rheumatology amd immunoallergology patients had higher average costs than gastroenterology patients, but it’s important to note that the differences in length of stay and costs were not formally explained by the treatment pathway. Meanwhile, the differences in health resource utilization were minimal.

This study came with its share of limitations including selection bias, as patients were randomly placed in cohorts; instead, they were placed based on observable variables. Further, the use of the billing data in a retrospective manner could have been impacted by data deficiency.

As a result, the study authors concluded that, “This descriptive cost study is one of the few analyses in the literature to use real-world data to examine the differences in outpatient and inpatient costs and length of stay between patients treated with CT-P13 and OI. Although CT-P13 has lower list and wholesale prices than OI, these differences were not reflected in overall outpatient or inpatient costs.

“Similarly, changes in therapeutic management caused by the implementation of a non-medical substitution strategy from OI to CT-P13 were not related to increased drug costs or healthcare resource utilization. This study contrasts with previous publications, which have reported mixed results regarding the impact of CT-P13 on hospital costs and supports the routine introduction of biosimilars in the hospital setting.”

Reference

1. Krstic, M., Devaud, JC., Sadeghipour, F. et al. Does the introduction of an infliximab biosimilar always result in savings for hospitals? A descriptive study using real-world data. Health Econ Rev 14, 31 (2024). https://doi.org/10.1186/s13561-024-00507-5