Filgrastim biosimilar(Changchun Genescience)

Multiple myeloma (MM) is the main indication for autologous stem cell transplantation (ASCT). Novel supportive therapies (e.g., granulocyte colony-stimulating factor) have significantly improved post-ASCT-related mortality; however, data on biosimilar pegfilgrastim-bmez (BIO/PEG) in this setting is lacking. This prospective cohort study compared Italian patients with MM who received BIO/PEG post-ASCT with data collected retrospectively from historical control groups from the same center who received either filgrastim-sndz (BIO/G-CSF) or pegfilgrastim (PEG; originator). The primary endpoint was time to neutrophil engraftment (three consecutive days with an absolute neutrophil count ≥ 0.5 × 109/L). Secondary endpoints included incidence and duration of febrile neutropenia (FN). Of the 231 patients included, 73 were treated with PEG, 102 with BIO/G-CSF, and 56 with BIO/PEG. Median age was 60 years and 57.1% were male. Neutrophil engraftment was reached after a median of 10 days in the BIO/PEG and PEG groups and 11 days in the BIO/G-CSF group. Among patients who achieved neutrophil engraftment earlier than this (i.e., day 9), 58% (29/50) were on PEG; of those who achieved it later (i.e., day 11), 80.8% (59/73) were on BIO/G-CSF. FN incidence was higher with BIO/G-CSF (61.4%) versus PEG (52.1%) or BIO/PEG (37.5%) (p = 0.02 among groups). Patients on BIO/PEG had less frequent grade 2–3 diarrhea (5.5%) compared with BIO/G-CSF (22.5%) or PEG (21.9%); grade 2–3 mucositis was most frequent in the BIO/G-CSF group. In conclusion, pegfilgrastim and its biosimilar displayed an advantageous efficacy and safety profile compared with biosimilar filgrastim in patients with MM post-ASCT.

During autologous stem cell transplant, granulocyte colony-stimulating factors (G-CSF) serve the integral role of mobilizing hematopoietic cells into the peripheral blood for subsequent collection by leukapheresis. Filgrastim (Neupogen®) is a G-CSF and affects hematopoietic cells by stimulating growth and differentiation of neutrophils. Filgrastim-sndz (Zarxio®), a biosimilar of filgrastim, received landmark approval as the first biosimilar product approved by the FDA in the United States. As a result of the recent FDA approval, our medical center made the conversion in August 2016 from using filgrastim to filgrastim-sndz to provide patients the same benefits of the filgrastim injection at a reduced cost. This retrospective, observational cohort study evaluated the comparative efficacy of the filgrastim-sndz biosimilar in 147 patients who underwent mobilization prior to stem cell transplant with filgrastim between 1 August 2015 and 31 July 2016 or filgrastim-sndz between 1 September 2016 and 30 November 2017. The mean number of CD34 cells collected during apheresis was 7.38 × 106 in the filgrastim group and 8.86 × 106 in the filgrastim-sndz group. Filgrastim-sndz was significantly non-inferior, as the difference between filgrastim and filgrastim-sndz was −1.48 × 106 with an upper 95% confidence bound equal to −0.24 × 106 that did not include the non-inferiority margin of 1 × 106 ( p = 0.0006). The median number of days of apheresis was 2 in both groups ( p= 0.3273). In conclusion, the biosimilar product was non-inferior for mobilization and the conversion from filgrastim to filgrastim-sndz afforded patients similar efficacy for mobilization in stem cell transplant at a reduced cost.