The findings of a retrospective observational study on healthcare resource utilization and cost patterns after formulary conversion to a biosimilar indicate that overall results may be driven by behavior at initial formulary switch.
A descriptive, retrospective, observational study analyzed real-world data on healthcare resource utilization (HCRU) and cost patterns after formulary conversion to the granulocyte colony-stimulating factor (GCSF) biosimilar filgrastim-sndz within a community oncology network during the initial period of conversion; these results were reported at the 2021 American Society of Clinical Oncology Annual Meeting.
Using electronic health record data from the US Oncology Network, this study identified patients with breast cancer at high risk for febrile neutropenia who received GCSF following myelosuppressive chemotherapy (MCT) from 2015 to 2017. Of note, the US Oncology Network converted to filgrastim-sndz in 2016. HCRU and costs for GCSF and complete blood counts were collected at GCSF initiation through the earliest of 30 days following end of MCT, loss to follow-up, death, or data cutoff.
This retrospective review identified a total of 146 eligible patients; of these, 81 (55.5%) received filgrastim reference and 65 (44.5%) received filgrastim-sndz. A higher proportion of patients in the filgrastim-sndz group received dose-dense MCT (33.8% vs 22.2%). After formulary conversion, there was an initial spike in HCRU and cost in the filgrastim-sndz group; these declined after 12 months and converged to those of the filgrastim group. The overall median total administration counts when aggregated were higher in the filgrastim-sndz group compared with the filgrastim group, per patient per month (2.9 vs 1.4) and dosage (1920 mcg vs 1440 mcg). For the filgrastim-sndz group, median per-patient per-month costs ($803 vs $545), median complete blood count utilization (2.8 vs 2.5), and costs ($28 vs $23) were higher.
Real-world insight into HCRU and cost patterns after formulary conversion to a biosimilar indicates that overall results may be driven by behavior at initial formulary switch.
Source: Rifkin RM, Herms L, Wentworth C, et al. Real-world utilization and costs with biosimilar and reference filgrastim in patients with breast cancer receiving myelosuppressive chemotherapy in a community oncology setting from 2015 to 2017. J Clin Oncol. 2021;39(suppl_28):57-57.
