Comparison between filgrastim biosimilar and filgrastim original for the management of neutropenia after salvage chemotherapy for malignant lymphoma

In this study, the efficacy and safety of filgrastim biosimilar (F-BS) were retrospectively compared to those of filgrastim original in the treatment of malignant lymphoma with CHASE (± R) or DeVIC(± R) in 78 patients. The median number of filgrastim doses was 11 in the F-BS group and 8 in the filgrastim group after CHASE (± R) (p = 0.8), and 10 in the F-BS group and 10 in the filgrastim group after DeVIC (± R) (p = 0.45). The median days until neutrophil recovery to ≥ 1000/μL was 10 days with F-BS versus 10 days with filgrastim after CHASE ± R (p = 0.59), and 9 days with F-BS versus 10 days with filgrastim after DeVIC ± R (p = 0.828). Febrile neutropenia (FN) was observed in 5 patients (41.7%) in the F-BS group and 9 (52.9%) in the filgrastim group after CHASE ± R therapy (p = 0.616), and in 11 patients (36.7%) in the F-BS group and 9 (47.4%) in the filgrastim group after DeVIC ± R (p = 0.462). The present results suggest that the efficacy and safety of F-BS are comparable to those of filgrastim original, with no significant differences in clinical factors. Use of F-BS also reduced medical costs per course of CHASE ± R therapy by 170.22 US dollars.

Comparative study of the number of report and time-to-onset of the reported adverse event between the biosimilars and the originator of filgrastim

PURPOSE

The objective of this study is to specify the most reported adverse events as preferred terms (PTs) and to compare the reported adverse events about some properties including the number of report and time-to-onset (TTO) distribution of the originator of filgrastim Neupogen® and its biosimilars in Europe, using VigiBase®.

METHODS

We identified the biosimilar which was reported as the suspected drug in more than 100 individual case safety reports in Europe. Then, we specified the top ranking 10 PTs in the cases reported with Neupogen® or each biosimilar as the suspected drug. We also compared the TTO of the most reported PTs using the data about the onset date of the PT and the start date of filgrastim. We used Kolmogorov-Smirnov method to detect significant difference.

RESULTS

The total ICSR numbers with Neupogen® and 3 biosimilars, Zarzio®, Nivestim®, and Tevagrastim® were 1,301, 295, 156, and 127, respectively, in Europe. The most reported PTs with Neupogen® were bone pain, pyrexia, and dyspnoea. The TTO of bone pain and pyrexia with Zarzio® (N: 22 and 16, median: 1 and 0.5 days) were significantly shorter than those with Neupogen® (P < 0.01, N: 72 and 33, median: 3.5 and 3 days), respectively. The most reported PTs with biosimilars were drug ineffective and neutropenia.

CONCLUSION

The difference in the TTO was identified between originator filgrastim Neupogen and its biosimilar regarding some PTs, which may suggest the difference in their safety profile. Copyright © 2017 John Wiley & Sons, Ltd.

Identification of Low-Level Product-Related Variants in Filgrastim Products Presently Available in Highly Regulated Markets

BACKGROUND

Filgrastim is a recombinant, non-glycosylated form of human granulocyte colony-stimulating factor, used to stimulate leukocyte proliferation in patients suffering from neutropenia. Since the expiration of patents associated with Amgen's filgrastim biopharmaceutical, Neupogen(®), in 2006, a number of filgrastim products have been marketed; however, a detailed characterization and comparison of variants associated with these products have not been publically reported.

OBJECTIVE

The objective of this study was to identify and quantify product-related variants in filgrastim reference products and biosimilars thereof that are presently available in highly regulated markets.

METHODS

In this study, we used intact and top-down mass spectrometry to identify and quantify product-related variants in filgrastim products. Mass spectrometry has become the method of choice for physicochemical characterization of biopharmaceuticals, allowing accurate and sensitive characterization of product-related variants.

RESULTS

In addition to modifications ubiquitously present in biopharmaceuticals, such as methionine oxidation and asparagine/glutamine deamidation, we identified six different low-level, product-related variants present in some, but not all, of the tested products. Two variants, an acetylated filgrastim variant and a filgrastim variant containing an additional C-terminal tryptophan extension, are newly identified variants.

CONCLUSION

This study demonstrates that filgrastim products already in widespread clinical use in highly regulated markets differ in low-level, product-related variants present at levels mostly below 1 % relative abundance. This study provides a comprehensive catalog of minor differences between filgrastim products and suggests that the filgrastim product-related variants described here are not clinically relevant when present at low abundance.

Pharmacokinetics and pharmacodynamics of FSK0808 and Gran after single intravenous drip administration or single subcutaneous administration: comparative study in healthy Japanese adult male subjects

FSK0808 is a recombinant human granulocyte colony-stimulating factor developed by Fuji Pharma Co., Ltd and Mochida Pharmaceutical Co., Ltd. as a biosimilar product of Gran®. We verified the pharmacokinetic/pharmacodynamic equivalence of FSK0808 and commercially available Gran® by a randomized crossover study of single intravenous dose (200 µg/m(2)) and single subcutaneous dose (400 µg/m(2)) in healthy Japanese adult male subjects. According to the bioequivalence guidelines, the area under the blood concentration - time curve by 48 hours after administration (AUC0-48) in a single intravenous drip (IVD) study, and AUC0-48 and maximum blood concentration (Cmax) in a single subcutaneous (SC) dose study were used as primary endpoints, and the pharmacodynamic parameters including absolute neutrophil count (ANC) or number of CD34 positive cells (CD34(+) cells) as secondary endpoints. The safety was evaluated based on the characteristics and incidence of adverse reactions. As a result, the 90% confidence interval (CI) of the difference in mean value for AUC0-48 among drugs ranged from log(0.8) to log(1.25), in the IVD study, and those for Cmax and AUC0-48 were within the range of log(0.8)-log(1.25) in the SC study. Those for secondary endpoints were all within the range of log(0.8)-log(1.25). Thus, the pharmacokinetics/pharmacodynamics of both drugs were considered equivalent for all routes of administration, and the profiles of adverse reactions were also very similar.