Updates on the Use of Biosimilars for Pediatric Patients with Rheumatic Disease

Although traditional disease-modifying antirheumatic drugs (DMARDs) are effective, their high cost has been a barrier to widespread accessibility for some patients. Now, as patents for these biologics begin to expire, the emergence of biosimilars has the potential to improve access to care.¹

Child with rheumatic disease | Image credit: luismolinero | stock.adobe.com

Biosimilars are highly similar to the reference product in clinical potency and toxicity but may have slight differences in components that do not appear to affect their effectiveness or toxicity.² Observational studies consistently demonstrate that biosimilars are comparable to the reference product with regard to safety and effectiveness.^1,2 Regardless, several barriers, including limited pediatric studies and patient misconceptions, have limited their clinical adoption in pediatric populations.

A team of researchers in Turkey conducted a comprehensive literature review evaluating studies that address the use of biosimilar products in pediatric rheumatic diseases. They included a total of 10 studies in their review, which aimed to provide insight and guidance to clinicians regarding biosimilars’ safety, efficacy, and economic impact in pediatric patients with rheumatic diseases.¹

They first looked at the biosimilar development process, which can be nearly 10% more cost-effective than the process used for the original products, largely because the FDA approves biosimilars based on extrapolation. Biosimilars can potentially come to market with only a single randomized clinical trial designed to show equivalent efficacy and immunogenicity between the biosimilar and the reference product. To obtain regulatory approval, the FDA requires a pharmacokinetic/pharmacodynamic study in humans, either healthy volunteers or patients, and at least 1 randomized controlled trial. The design of the randomized controlled trials should be based on an equivalence margin related to the primary end point difference between active treatment and placebo. The study authors recommend that clinicians review the FDA Purple Book to obtain more information on the comparability programs associated with biosimilar products.¹

The literature review also discussed safety and efficacy of biosimilar products. Although they found a lack of clinical trials involving children and young adults, the few studies reviewed showed similar efficacy and safety between the reference product and the biosimilar. One of the main challenges with the uptake of biosimilars is that randomized controlled trial data are generally limited, despite robust data for the original product. Additionally, when biosimilars are FDA-approved, approval for a single indication based on similarity and efficacy of the original molecule, along with a single randomized clinical trial, is typically sufficient. These factors can contribute to the nocebo effect, which the authors describe as expectations which lead to negative outcomes, thereby playing a potential role in the discontinuation of biosimilars.¹

The authors conclude that more research is needed on the use of biosimilars in pediatric patients with rheumatic diseases. However, they acknowledge that these therapies hold significant potential in this population, particularly with regard to cost savings. They reiterate that observational studies have continued to consistently demonstrate that biosimilars are comparable to original biologics with no significant difference in treatment discontinuation or disease activity. Providing ongoing education to both patients and providers, maintaining transparent communication, and conducting further research will enhance the success of biosimilars in pediatric populations in the future.

REFERENCES

1. Öksel A, Sönmez HE, Şahin N. Biosimilars in pediatric rheumatology: innovations, challenges, and opportunities. Expert Opin Biol Ther. 2025;25(2):197-204. doi:10.1080/14712598.2025.2453516

2. Manis JP. Overview of therapeutic monoclonal antibodies. In: UpToDate. Tobian A, Tirnauer JS & Feldweg AM (Eds). Wolters Kluwer. Updated October 29, 2024. Accessed February 11, 2025