Objective: To compare the efficacy and safety of daily administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF), and a single subcutaneous injection of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF), a sustained-duration rhG-CSF, in chemotherapy-induced neutropenia.
Methods: In the present randomized, open-label, match and cross-over study, enrolled 104 patients with previously untreated non-small cell lung cancer (NSCLC), breast cancer or non-Hodgkin's lymphoma and with normal bone marrow function from 13 centers were randomly divided into 2 matched groups, AB and BA group. Each patient received two cycles of chemotherapy of identical regimen. In the study cycle, the patients received a single subcutaneous injection of PEG-rhG-CSF 100 microg/kg on day 3; and in control cycle, daily subcutaneous infection of rhG-CSF 5 microg x kg(-1) x d(-1) began on day 3 and continued for 14 days or until the absolute neutrophil count (ANC) became > or = 5.0 x 10(9)/L twice after it decreased to the nadir. Efficacy and safety parameters were monitored.
Results: The incidence rates of ANC < 1.5 x 10(9)/L in the 103 evaluable study cycles and 100 evaluable control cycles were 30.00% and 20.00% with the duration of 2.39 days and 2.35 days respectively. The incidence rates of grade 3 neutropenia were 7.77% and 7.00%; and that of grade 4 neutropenia were 5.80% and 4.00% respectively in the trial and control cycles. However, all the difference mentioned above did not reached statistical significance. None of the patients experienced febrile neutropenia. The ANC nadir was (7.55 +/- 5.25) x 10(9)/L and (8.42 +/- 5.57) x 10(9)/L (P = 0.257) respectively after receiving PEG-rhG-CSF and rhG-CSF. Compared with that of rhG-CSF group, the ANC profile of PEG-rhG-CSF group exhibited limited "overshoot" of neutrophils after the nadir. Subgroup analysis according to disease type yielded similar results. The safety profiles of the PEG-rhG-CSF and rhG-CSF groups were similar. Musculoskeletal pain or arthralgia occurred in 16.5% of the study cycles and 26.00% of the control cycles (P = 0.963), mostly mild or moderate. Other adverse effects such as fever, fatigue, dizziness, gastrointestinal effects and injection-site pain, were transient and easily manageable.
Conclusion: A single subcutaneous injection of PEG-rhG-CSF 100 microg/kg provides neutrophil support and a safety profile comparable to regimen of daily subcutaneous injection of rhG-CSF 5 microg x kg(-1) x d(-1) in Chinese patients receiving a variety of myelosuppressive chemotherapy regimens.