Early Insights into Biosimilar Cost Savings in the United States

November 26, 2018

A recent study in JAMA Oncology examined the average daily cost of biosimilar filgrastim-sndz compared with the brand name biologic.

Although adoption has been slow in United States, biosimilar filgrastim-sndz has a 10% lower average daily treatment cost than the brand name biologic, an observational study found. Biosimilar filgrastim-sndz earned US Food and Drug Administration (FDA) approval in March 2015, making it the first biosimilar in the United States. The study insights suggest that the recent entry of biosimilar products in the United States may deliver on the promise of lower costs. The results were published in November in JAMA Oncology.

“This is the kind of data we need now and in the coming years to track the uptake of [biosimilars],” Gary Lyman, MD, MPH, told Cancer Network. Lyman is senior lead of healthcare quality and policy for the Hutchinson Institute for Cancer Outcomes Research in Seattle. He was not involved in the current study. However, he cautioned, “It’s very early data.”

To evaluate biosimilar uptake and cost savings, researchers retrospectively evaluated administrative health claims data for adult cancer patients who were privately insured in the United States. Patients included in the analysis were treated with chemotherapy and received reference filgrastim or one of two biosimilar agents between September 1, 2012, and April 30, 2017. The biosimilar agents were filgrastim-sndz and tbo-filgrastim. Total cost of filgrastim as well as cost per day of use were calculated.

A total of 11,202 patients were included in the analysis, of which 568 patients (5.1%) received filgrastim-sndz and 963 patients (8.5%) received tbo-filgrastim. The authors reported no meaningful differences in baseline risk factors between patients who received reference filgrastim and biosimilar filgrastim.

The study researchers explored differences in safety and efficacy between reference filgrastim and biosimilar filgrastim. They found similar incidence rates of febrile neutropenia and adverse events between groups, concluding that biosimilar filgrastim is similar to reference filgrastim in terms of safety and effectiveness.

Lyman disagreed, explaining that the study design did not lend to this conclusion because the patients were not randomized to treatment and it’s too early to determine. “This kind of data is purely exploratory or hypothesis generating,” he asserted. That said, he noted that he does believe biosimilar filgrastim has similar safety and efficacy to the originator product, but not based on this data alone.  

The analysis revealed that the average cost per day of use for filgrastim-sndz was 10.8% lower than the reference product ($667 vs $748; P < .001). The total cost per patient was 6.1% lower ($2,363 vs $2,516; P = .07).

“One might argue there’s not much difference, but I guess I’m looking at it as the glass half full,” Lyman said about the cost. “In the first 2 years with one biosimilar on the market, we’ve seen a 10% reduction in price for that biosimilar.”

For tbo-filgrastim, the cost was actually found to be slightly more than the reference product. Lyman explained that tbo-filgrastim is technically not a biosimilar in the United States. The manufacturer of tbo-filgrastim still had to conduct the usual clinical trials that would be required of an originator product because, at the time of the development of tbo-filgrastim, the approval pathway for biosimilars had not yet been established by the FDA. As a result, tbo-filgrastim has all the typical costs associated with drug development.

“I would hope if this data is updated in the next 2 to 3 years with more biosimilar filgrastim molecules in the marketplace-and we now have several that have been approved-that we will see more [cost reduction] than this,” Lyman said.

In Europe, around a 20% reduction in price has been seen for biosimilar products compared to the brand name product. “This early indication is there is some impact on price with the biosimilar filgrastim, but we would hope for more, and kind of expect more, as more and more of these drugs get approved.”