Cencora Analysis Shows Differences in Payer Coverage Between G-CSF Biosimilars

According to a study by Cencora, there is a discrepancy in payer coverage for granulocyte colony-stimulating factor (G-CSF) biosimilars. Although filgrastim biosimilars are frequently preferred over the originator (Neupogen), reference pegfilgrastim (Neulasta) continues to hold a dominant position over its biosimilar counterparts.

The data were presented at the Academy of Managed Care Pharmacy’s annual meeting in New Orleans, Louisiana. The analysis was conducted to “provide a descriptive analysis of US payer commercial coverage policies on biosimilars over time, with a focus on [G-CSF] therapies.”

As of May 2024, there are 3 FDA-approved filgrastim biosimilars (Zarxio, Nivestym, and Releuko) and 6 pegfilgrastim biosimilars (Udenyca, Nyvepria, Ziextenzo, Stimufend, Fulphila, and Fylnetra), 1 of which has been approved with an on-body injector (Udenyca; pegfilgrastim-cbqv). Although the number of biosimilars in the US is growing, the US still lags behind Europe in approvals and uptake, in part because of biosimilars not being preferred at parity or over their reference products.

Researchers looked at biosimilar coverage policies from the top 50 US payers to identify published historical changes through July 2023. They also analyzed payer websites for availability of policies and robustness of historical policy records. The policies were reviewed to extract filgrastim and pegfilgrastim biosimilar coverage status and payer’s choice of preferred product.

From the analyzed payers, 38 (76%) had policies for filgrastim and 42 (84%) has policies for pegfilgrastim.

For filgrastim biosimilars, 32 (84%) payers preferred Zarxio (filgrastim-sndz), which was the first biosimilar approved in the US. Nivestym (filgrastim-aafi) was the second most preferred filgrastim product, with 14 (37%) payers selecting it as the preferred product. Eleven percent (n = 4) of payers placed filgrastim biosimilars at parity with the originator. Filgrastim biosimilars were added to policy an average of 4.7 months after receiving FDA approval.

Regarding pegfilgrastim biosimilars, 62% (n = 26) of payers preferred Ziextenzo, 60% (n = 25) preferred Neulasta, 55% (n = 23) preferred Fulphila. Nyvepria, Fylnetra, and Stimufend were the most common pegfilgrastim products to not have preferred status. Preference for Udenyca was split, with 19 (45%) payers choosing to prefer it and 19 (45%) choosing not to. Only 3 (17%) payers placed Neulasta and its biosimilars at parity with one another.

Of the 18 policies for pegfilgrastim policies with historical records, 66% have changed their list of preferred products. On average, pegfilgrastim biosimilars were added to a policy 4.1 months after FDA approval.

The study had some limitations, including that the research was limited to publicly available information. Additionally, the time to biosimilar policy adoption may not accurately represent the time it takes for payers to review and create coverage policies for therapies.

The authors concluded, “Future market research should investigate factors that led to Neulasta retaining much of its preferred status compared to Neupogen. Research should also aim to understand which factors led to a minority of payers placing innovator products and their biosimilars at parity with one another.”

Reference

Frank T, Pearson A, Hilton PB, Riggs K, Noonan KA. Changes in US payer biosimilar coverage policies of granulocyte colony-stimulating factor products. Presented at: AMCP 2024; April 15-18, 2024; New Orleans, LA. Poster U15.