Adoption of Biosimilars Varies by Practice Setting

The use of biosimilars to treat patients may differ across drug classes, according to a new study examining the relationship between biosimilar use and practice setting and patient/physician characteristics.¹ The factors with the strongest association of use include the practice setting (office vs hospital outpatient department) and hospital outpatient ownership status, according to the results of a study of Medicare patients.

Patient characteristics were only weakly associated with biosimilar use.

The products studied include: filgrastim (Neupogen; Amgen) and its biosimilars filgrastim-sndz (Zarxio; Sandoz) and tbo-filgrastim (Granix; Teva), which are used to reduce infection in patients receiving myelosuppressive anticancer drugs.

Administrations of filgrastim biosimilars in the hospital outpatient setting were 16.1% less likely to be biosimilars. Within an office or hospital outpatient setting, filgrastim biosimilars were more likely to be administered in larger offices or hospital outpatient departments and were 17.4% less likely to be administered in a for-profit setting than a not-for-profit setting.

The study also looked at use of infliximab (Remicade; Johnson & Johnson) and its biosimilars, which are used to treat patients with Crohn’s disease, ulcerative colitis, and rheumatoid arthritis. Investigators found that patients in the hospital were more likely to receive these biosimilars than those in an office setting.

The authors point out that hospital outpatient departments are able to receive larger discounts on the reference products than smaller offices due to their high-volume purchasing, which they said could be an explanation for slower filgrastim-sndz uptake in the hospital outpatient setting. This, the authors say, represents a lost opportunity for cost savings.

Savings generated by biosimilars are predicted to be about $100 billion in aggregate over the next 5 years, according to a report by IQVIA Institutes for Human Data Science.²

To demonstrate cost savings, 1 organization conducted a study of the savings it expects to see by switching from the reference product to the biosimilar. Intermountain Healthcare in Salt Lake City, Utah, annually administers about 6450 combined doses of pegfilgrastim (Neulasta; Amgen), bevacizumab (Avastin; Genentech), trastuzumab (Herceptin; Genentech), and rituximab (Rituxan; Genentech), said Megan Mullalley, PharmD, during a presentation at the 2020 American Society of Clinical Oncology’s Quality Care Symposium in October 2020.³

Assuming 70% conversion from the reference medication to a biosimilar agent for these agents, Mullalley predicted biosimilars would save an estimated $6.3 million annually. This includes a $1.75 million savings from transitioning to rituximab alone. In addition, transitioning trastuzumab from a single-dose vial to multidose vials is estimated to save an additional $730,000. (Table.)

*Based on 70% conversion from the reference product to biosimilars

**Trastuzumab biosimilars in multidose vials would save an additional $730,000

“Biosimilar agents can reduce the cost of oncology care to patients at our institution, and they reduce financial toxicity of cancer,” Mullalley said in her presentation.

References

1. Dean EB, Johnson P, Bond AM. Physician, practice, and patient characteristics associated with biosimilar use in Medicare recipients. JAMA Netw Open. Published online January 27, 2021. 2021;4(1):e2034776. doi:10.1001/jamanetworkopen.2020.34776
2. Biosimilars in the United States 2020-2024. IQVIA Institutes for Human Data Science. October 2020. Accessed March 16, 2021. https://www.iqvia.com/-/media/iqvia/pdfs/institute-reports/iqvia-institute-biosimilars-in-the-united-states.pdf?_=1616093010649
3. Mullalley M, Mortensen W, Barnette P, et al. Cost savings of biosimilars in oncology: a single institution experience. J Clin Oncol. 2020;38(29). doi:10.1200/JCO.2020.38.29_suppl.10