A Randomized, Placebo-Controlled Phase II Study Evaluating the Reduction of Neutropenia and Febrile Neutropenia in Patients With Colorectal Cancer Receiving Pegfilgrastim With Every-2-Week Chemotherapy

Background: Adding irinotecan and/or oxaliplatin to every-2-week 5-fluorouracil (5-FU)/leucovorin (LV) prolongs survival in patients with colorectal cancer (CRC) but increases neutropenia frequency. Pegfilgrastim is indicated to decrease infection as manifested by febrile neutropenia (FN) in patients receiving chemotherapy at > 14-day intervals. This randomized, placebo-controlled phase II study examined pegfilgrastim efficacy and safety in patients with CRC receiving every-2-week chemotherapy. Patients and Methods: Patients with CRC were randomized 1: 1 to pegfilgrastim 6 mg or placebo administered per-cycle on day 4. Randomization was stratified by chemotherapy regimen (patients received every-2-week FOLFOX4 [5-FU/LV/oxaliplatin], FOLFIRI [5-FU/LV/irinotecan], or FOIL [5-FU/LV/oxaliplatin/irinotecan] at physician discretion). The primary endpoint was incidence of grade 3/4 neutropenia. Secondary endpoints included incidence of grade 3/4 FN and adverse events. After 4 cycles of study treatment, progression-free survival (PFS) and overall survival (OS) were followed for <= 2 years in long-term follow-up. Results: Of 241 eligible patients analyzed, 118 were in the placebo and 123 in the pegfilgrastim group. In the treatment period, the odds ratio for grade 3/4 neutropenia for pegfilgrastim versus placebo was 0.19 (95% CI, 0.10-0.37; P<.001); grade 3/4 FN incidence was also significantly lower in pegfilgrastim-treated patients (2%) compared with placebo-treated patients (8%; P=.04). Pegfilgrastim was well tolerated, with leukocyte counts remaining stable during cycles 2-4. In long-term follow-up, both treatment groups had similar PFS and OS. Conclusion: Pegfilgrastim was well tolerated in patients with CRC receiving every-2-week chemotherapy and significantly reduced neutropenia and FN compared with placebo, though FN was uncommon in both treatment groups. Results suggest that pegfilgrastim administration is feasible in CRC patients receiving every-2-week chemotherapy.