# The safety and effectiveness of pegfilgrastim to reduce cancer chemotherapy-induced febrile neutropenia in real-world practice in Japan: a post-marketing surveillance study

## TL;DR

This study evaluated pegfilgrastim's safety and effectiveness in preventing febrile neutropenia in cancer patients undergoing chemotherapy in Japan.

## Contribution

The study provides real-world evidence on pegfilgrastim's effectiveness and safety in reducing febrile neutropenia in Japan.

## Key findings

- Pegfilgrastim reduced febrile neutropenia in both primary and secondary prophylaxis settings.
- Common adverse drug reactions included back pain, pyrexia, and arthralgia, which were mostly non-serious.
- Docetaxel-cyclophosphamide therapy was associated with increased risk of bone and back pain-related adverse events.

## Abstract

We performed post-marketing surveillance of the safety and effectiveness of 3.6 mg pegfilgrastim to prevent chemotherapy-induced febrile neutropenia (FN) in real-world conditions in Japan.

Patients were registered between June 2015 and May 2017 and followed prospectively. Pegfilgrastim was administered once every chemotherapy cycle (maximum 6 cycles). Use of pegfilgrastim, safety, and effectiveness in reducing FN were evaluated.

From 300 institutions, 1,597 patients were registered and 1,479 patients were analyzed. Pegfilgrastim was given as primary prophylaxis (750 patients), as secondary prophylaxis (727 patients), or for therapeutic purposes (2 patients). The most common primary diseases were breast cancer (51.4%) and non-Hodgkin lymphoma (25.6%). Adverse events (AEs) occurred in 36.4% of patients and adverse drug reactions (ADR) in 18.5%. Common ADRs included back pain (3.6%), pyrexia (3.1%), arthralgia (2.1%), hepatic function abnormal (1.5%), myalgia (1.4%), and bone pain (1.0%). All back and/or bone pain-related ADRs were non-serious and well-controlled with non-steroidal anti-inflammatory drugs. Docetaxel-cyclophosphamide therapy among breast cancer patients was a factor influencing bone and/or back pain-related AEs by multivariate logistic regression analysis (odds ratios vs. fluorouracil-epirubicin-cyclophosphamide therapy: 2.32, P = 0.031).

FN was observed in 5.3% (primary prophylaxis) and 2.5% (secondary prophylaxis) of the effectiveness analysis set in cycle 1 and decreased with increasing cycles.

This survey confirmed that both primary and secondary prophylaxis using pegfilgrastim reduced FN in the real-world setting. No new safety concerns were identified.

This survey was retrospectively registered on 26 April 2024 in the University Hospital Medical Information Network Clinical Trial Registry (UMIN000054267).

The online version contains supplementary material available at 10.1007/s00520-025-10042-6.