A phase 3 trial of GB-K02 pegfilgrastim biosimilar for preventing chemotherapy-induced neutropenia in breast cancer

Chemotherapy-induced neutropenia (CIN) constitutes a substantial disease burden globally. Although pegfilgrastim (a long-acting granulocyte-colony stimulating factor) has demonstrated efficacy in preventing CIN, it is not yet available in China. This is the first clinical study to evaluate a pegfilgrastim biosimilar in China. This multicenter, randomized, double-blind, parallel-controlled, phase 3 equivalence study aims to evaluate the efficacy and safety of GB-K02 (a pegfilgrastim biosimilar) in preventing CIN among 250 patients with breast cancer. The primary efficacy endpoint was the duration of grade 4 neutropenia (DG4N) in cycle 1 of chemotherapy. The DG4N (LSMean ± SE) in cycle 1 was 0.58 ± 0.13 days versus 0.80 ± 0.13 days (p = 0.2139) for the GB-K02 group and the pegfilgrastim group, respectively. Other efficacy endpoints and safety were also similar between the two groups in 4 cycles of chemotherapy. Overall, GB-K02 demonstrated proper equivalence to pegfilgrastim and might offer an option in preventing CIN in China.