Does biosimilar filgrastim improve neutropenia in older DLBCL patients receiving chemotherapy?

This study analyzed the outcomes of older patients with stage 3 or 4 DLBCL (diffuse large B-cell lymphoma) who received biosimilar filgrastim (Neupogen) during their chemotherapy. The study concluded that filgrastim was safe and effective in these patients.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphoma (NHL), accounting for about 30% of new NHL cases in the U.S. The most widely used treatment for this aggressive cancer is R-CHOP, which combines rituximab (Rituxan) with a CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone).

50% of treated patients develop a condition called neutropenia, or abnormally low levels of neutrophils (white blood cells) in the blood. This can make them more susceptible to infections. Administering G-CSFs (granulocyte-colony stimulating factors) like filgrastim helps increase neutrophil levels. This has been recommended for patients at risk for neutropenia. The safety and effectiveness of this treatment outside of clinical trials, and in older patients, is still under investigation.

This study involved 245 patients 65 or older (average age of 62.7 years): 103 patients with stage 3 disease and 135 patients with stage 4 disease. Of these, 159 patients received a CHOP-based chemotherapy cocktail, with R-CHOP-21 being the most common (113 patients). 239 patients received the biosimilar filgrastim.

During the study period, 35.5% patients had one or more episodes of chemotherapy-induced neutropenia. 9.8% experienced febrile neutropenia (fever associated with neutropenia). Other effects reported included bone pain (2.9%), joint pain (0.8%), and back pain (0.8%).

This study concluded that the biosimilar filgrastim is safe and effective in DLBCL patients, including those aged 65 or older. 

The current study only included a small subset of 245 patients from the larger MONITOR-GCSF study of 1,447 patients. Neutropenia outcomes were similar in both studies (35.5% versus 34.8% of patients showed CIN and 9.8% versus 5.9% of patients showed FN), but comparing this study to clinical trials is limited. Patients in clinical trials are more closely monitored, so G-CSFs may be used differently. Patient populations can also differ, including age and chemotherapy regimens. More studies examining the preventative use of filgrastim in patients with non-Hodgkin's lymphoma are needed, with larger sample sizes in real-life settings.

If you are 65 years or older and are undergoing chemotherapy for DLBCL, talk to your care team about taking biological filgrastim to prevent neutropenia.