Feasibility Re-evaluation of 75 mg/m2 Docetaxel in Japanese Patients with Previously Treated Non-small Cell Lung Cancer

Objective: The primary objective of this study was to re-evaluate the feasibility of docetaxel at doses of up to 75 mg/m 2 in Japanese patients with previously treated non-small cell lung cancer. Methods: Patients received escalated doses of docetaxel at 70 mg/m 2 (level 1) or 75 mg/m 2 (level 2) every 3 weeks until disease progression or unacceptable toxicities. Dose escalation was decided on the basis of dose-limiting toxicity in the first cycle of chemotherapy. Results: At dose level 1, dose-limiting toxicity—Grade 3 febrile neutropenia—was observed in one of the six patients and at dose level 2, it was seen in one of the first six patients. Therefore, an additional 14 patients were enrolled at dose level 2, as originally planned. Among the total of 20 patients at dose level 2, 6 (,33%) developed dose-limiting toxicity in the first cycle: febrile neutropenia in 5 and pneumonia in 1. Finally, 10 (50%) of the 20 patients experienced toxicities that met the dose-limiting toxicity criteria, including 8 with febrile neutropenia throughout the treatment period, but this was manageable with dose reduction or appropriate supportive care. Other observed toxicities were predictable from the safety profile of decetaxel and were also well managed. Four partial responses were observed, giving an overall response rate of 15.4%. The median progression-free survival period of the patients overall was 4.0 months (95% confidence interval 1.4‐6.6 months). Conclusions: Although docetaxel administration at an initial dose of 75 mg/m 2 requires careful attention because of the high incidence of febrile neutropenia, this dose is considered feasible according to the protocol definition in Japanese patients with previously treated non-small cell lung cancer.