Second-line pemetrexed treatment in Taiwanese patients with advanced nonsmall cell lung cancer

Background/Purpose: Although global and Asian studies on second-line pemetrexed for the treatment of advanced nonsmall cell lung cancer have confirmed its efficacy and safety, a pivotal postcommitment study to consolidate the evidence regarding the Taiwanese population was warranted. This open-label single-arm study assessed the objective response rate to a tailored dose of single-agent pemetrexed in Taiwanese patients with advanced nonsmall cell lung cancer who had received prior chemotherapy. Methods: Patients with stage IIIB/IV disease were treated with pemetrexed on day 1 of each 21-day cycle. A 500mg/m2 dose was administered in cycle 1. For cycle 2, the dose was increased to 1000mg/m2 (if there was no toxicity above predefined levels) or decreased to 375mg/m2. All patients received standard supplemental therapy. Patient follow-up continued until 18 months after the last patient was enrolled in this study or death. All patients were included in all analyses. Results: Of the 33 patients who were enrolled, 25 (75.8%) received the 1000mg/m2 dose during cycle 2; 18 patients were dropped from the study, including 17 (51.5%) who had died by the time of analysis. The objective response and disease control rates were 18.2% (95% confidence limits [CI]: 7.0-35.5) and 54.5% (95% CI: 36.4-71.9), respectively. No patients exhibited a complete response. There were two serious drug-related adverse events (neutropenia and leukopenia) and two drug-related adverse events that resulted in removal from the study. Decreased neutrophil/granulocyte counts were the most frequently observed drug-related grade 3/4 events (9 patients, 24 treatment cycles). Conclusion: The objective response rate, disease control rate, and safety and tolerability profile in this population of Taiwanese patients were consistent with the published findings that were conducted using Asian and Western populations. These findings support the use of single-agent, second-line pemetrexed for the treatment of advanced nonsmall cell lung cancer in Taiwanese patients.