Long-acting granulocyte colony-stimulating factor in primary prophylaxis of early infection in patients with newly diagnosed multiple myeloma

PURPOSE: This study sought to compare the efficacy of prophylactic long-acting and standard granulocyte colony-stimulating factor (G-CSF) on febrile neutropenia, early infections, and treatment delay in patients with newly diagnosed multiple myeloma (MM) receiving the therapeutic regimen of bortezomib, lenalidomide, and dexamethasone (VRd). METHODS: A prospective study with 68 consecutive patients with MM was conducted in three regional hospitals. Participants were randomly treated with the VRd regimen in combination with prophylactic long-acting G-CSF (treatment group) or prophylactic standard G-CSF (control group). The primary endpoints were the incidence rates of febrile neutropenia, early infection, and treatment delays. The secondary endpoint was clinical outcomes. RESULTS: Thirty-three patients were assigned to the treatment group, and thirty-five patients were assigned to the control group. The incidence of febrile neutropenia was 6.1% and 17.1% in the treatment and control groups, respectively (p = 0.297). However, the rates of early infection and treatment delay were markedly lower in the treatment group than in the control group (6.1% vs. 25.7% and 9.1% vs. 31.4%; p < 0.05). Notably, all early infections occurred during the first four cycles of VRd therapy, and the most common type of infection was pneumonia. No significant difference in clinical efficacy was found between the two groups. All participants achieved at least partial remission. CONCLUSIONS: Prophylactic administration of domestic long-acting G-CSF markedly reduced the rates of early infection and treatment delay as compared with standard G-CSF in patients newly diagnosed with MM. Notably, all early infections occurred during the first four cycles of VRd therapy. As such, it seems appropriate to administer long-acting G-CSF with the aim of primary prophylaxis of early infection in the setting of newly diagnosed MM.