Subcutaneous Administration of Recombinant Human Granulocyte Colony‐stimulating Factor (KRN8601) in Intensive Chemotherapy for Patients with Advanced Lung Cancer

The efficacy and toxicity of recombinant human granulocyte colony‐stimulating factor (rh G‐CSF, KRN8601) given subcutaneously was evaluated in patients with advanced lung cancer undergoing intensive chemotherapy. Twenty‐nine and 30 patients with or without prior therapy were enrolled in this study. At dose levels of 50, 90 and 130 μg/m(2) of rh G‐CSF for 14 consecutive days after chemotherapy, the mean neutrophil nadir counts, the mean neutrophil nadir ratios and the duration of neutropenia (days of < 1000/mm(3)) were significantly improved. No significant differences were seen in frequency and duration of febrile episodes (>38°C). When rh G‐CSF is given subcutaneously, the dose required for an equal effect in alleviating neutropenia is 50% of that required when it is given intravenously. The monocyte counts in the peripheral blood were also significantly increased after chemotherapy cycles with rh G‐CSF. The cumulative plasma concentration of rh G‐CSF showed a decrement after 7–9 days despite maintenance of the same dose of rh G‐CSF for the entire 14 days. In conclusion, 50–130 μg/m(2) of sc rh G‐CSF increased the neutrophil nadir count and shortened the duration of neutropenia in patients undergoing intensive chemotherapy for lung cancer without intolerable side effects.