Granulocyte Colony Stimulating Factor in the Prevention of Chemotherapy-Induced Neutropenia in Patients With Colorectal Cancer Receiving Trifluridine/Tipiracil: A Real-World UK Retrospective Review

Introduction Trifluridine-tipiracil (FTD/TPI) is approved as monotherapy and in combination with bevacizumab for the treatment of metastatic colorectal cancer (mCRC). This UK real-world retrospective analysis aimed to evaluate the use of granulocyte colony stimulating factor (G-CSF) to prevent FTD/TPI induced neutropenia in patients with mCRC. Methods Retrospective data were collected across five UK Healthcare sites. Consecutive patients with mCRC having received at least 2 cycles of FTD/TPI in addition to G-CSF administered as primary or secondary prophylaxis were included. The study assessed the timing and duration of G-CSF treatment, incidence of neutropenia, and subsequent dose delays/reductions. Time on FTD/TPI treatment, Progression free Survival (PFS), and Overall Survival (OS) were also calculated for this patient cohort. Results The data set included 55 mCRC patients in total; 25 receiving primary prophylaxis, and 30 receiving secondary prophylaxis. 68% of G-CSF prophylaxis commenced on day 15, with 99% initiated between days 14 and 22. Following G-CSF use, 25% of patients experienced a dose delay and 18% a dose reduction due to neutropenia. 14.5% of patients reported grade ≥3 neutropenia. In patients receiving primary prophylaxis a mean of 18.4 weeks of FTD/TPI were completed, whereas in those receiving secondary prophylaxis the mean was 28.8 weeks. Primary prophylaxis patients exhibited a median PFS of 3 months, and a median OS of 9.7 months. In secondary prophylaxis patients the median PFS was 7.2 months and the median OS 17.5 months. Conclusion G-CSF prophylaxis reduced the incidence of neutropenia, improved dose intensity, and extended PFS and OS in this real-world study of mCRC patients on FTD/TPI. G-CSF prophylaxis was commonly administered as a 5-day course of filgrastim starting on day 15.