Biosimilar Filgrastim Similar to Reference Product When Used in NSCLC

There are limited data on the use of biosimilar filgrastim in the prophylaxis of chemotherapy‐induced neutropenia (CIN) and febrile neutropenia (FN) for patients with non‐small cell lung cancer (NSCLC) in real-world settings. Now, new data from a subset analysis of MONITOR‐GCSF, a multicenter study from Europe, show that biosimilar filgrastim (Zarxio, Zarzio) has similar effectiveness and safety to reference filgrastim (Neupogen).

The authors say the findings support the use of biosimilar filgrastim in place of the reference in patients with NSCLC.

G‐CSF is often not used according to international recommendations, highlighting a need for additional data from observational studies to help guide optimal use; this may be particularly important for older patients who are at high risk of CIN and FN, the researchers write.

In MONITOR‐GCSF, a prospective, non‐interventional study, researchers sought to describe patient characteristics, treatment patterns, and clinical outcomes in 345 patients with stage 3 or 4 NSCLC receiving up to 6 cycles of biosimilar filgrastim with their chemotherapy.

Monotherapy regimens used by patients included docetaxel and topotecan. The most commonly prescribed combination chemotherapy regimen was cisplatin and etoposide.

A total of 126 (36.5%; 95% CI, 32%-42.19%) patients experienced 1 or more episode of CIN of any grade and 18 (5.2%; 95% CI, 3.36%-8.19%) patients had FN of any grade throughout the duration of the study.

In cycle 1, CIN occurred in 47 (13.6%; 95% CI, 10.53%-17.85%) patients and FN occurred in 5 (1.4%; 95% CI, 0.63%-3.39%) patients. Grade 3 or 4 FN occurred in 4 patients (1.2%; 95% CI, 0.46%-2.98%) in cycle 1 and in 13 patients (3.8%; 95% CI, 2.24%-6.41%) in all cycles.

Adverse events were reported in 0.3% of patients, and included arthralgia, bone pain, cough, gastroenteritis, and myalgia.

A large proportion of patients (80% or more) experienced changes to their chemotherapy regimen, whether for chemoresistance, lack of efficacy, tolerability concerns, and disease progression.

According to the authors, the findings from this subset analysis of patients with NSCLC demonstrate that biosimilar filgrastim is safe and effective in real-world practice, and that it has a similar profile to the reference product.

Reference

Aapro M, Krendyukov A, Höbel N, Gascon P. Treatment patterns and outcomes in patients with non‐small cell lung cancer receiving biosimilar filgrastim for prophylaxis of chemotherapy‐induced/febrile neutropaenia: Results from the MONITOR‐GCSF study [published online April 10, 2019]. Eur J Cancer Care. doi: 10.1111/ecc.13034.