According to budget projections, filgrastim biosimilars could save health insurers millions of dollars each year as they seize more market share from the branded drug, Neupogen, a granulocyte colony-stimulating factor (G-CSF).
The analysis was presented by Susan Gabriel, director of global health economics and outcomes research for Teva Pharmaceuticals, at the American Society of Hematology’s 2016 meeting. It assessed the potential monetary impact on payers of increased use of filgrastim-sndz, sold by Sandoz as Xarxio, and tbo-filgrastim, sold by Teva as Granix.
Tbo-filgrastim is not technically regarded as a biosimilar, as it preceded the development of the FDA’s biosimilars approval pathway, but its Biologics License Application was approved after it demonstrated comparable safety, efficacy, and pharmacokinetic activity to Neupogen.
Analysts ran a model, which assumed that tbo-filgrastim would take 5% of the market share over a 1-year period and filgrastim-sndz would take 2%, resulting in a total 7% loss of market share for filgrastim. They calculated the annual drug cost per patient based on a regimen of 6 cycles of 10 days each. Their estimates for the yearly per-patient costs in both medical benefits and pharmacy benefits are as follows:
Overall, the use of short-acting G-CSFs for 1 million members would cost a health plan $177.1 million annually under the current scenario and $175.2 million in the future scenario, representing a yearly saving of almost $2 million. The model was sensitive to changes in the proportion of patients whose G-CSF drugs are administered by their healthcare providers, and to fluctuations in the average price per dose of filgrastim.
G-CSFs like filgrastim are used to fight neutropenia in patients receiving chemotherapy, as they work similar to the body’s proteins that signal to the bone marrow to produce more neutrophils. Neutropenia is a common and serious complication for many cancer patients, as it can result in severe infections and even death.
Due to the high price tag of the branded drug, payers, clinicians, and patients alike are looking to biosimilars as a potentially less expensive solution.
“Based on these assumptions, a million-member health plan could save almost $2 million per year by switching over to tbo-filgrastim as opposed to filgrastim or filgrastim-sndz,” Gabriel concluded. “However, as with any budget impact model, estimated results based on future product market share should be interpreted cautiously.”