Phase II trial of sequential gefitinib after minor response or partial response to chemotherapy in Chinese patients with advanced non-small-cell lung cancer.

Background: Basic research of gefitinib (Iressa, ZD1839) has demonstrated the combination effects of gefitinib and chemotherapy were sequence-dependent. To evaluate the efficacy of sequential administration of gefitinib following a minor response or partial response to two to three cycles of chemotherapy, a phase II clinical trial was done in Chinese patients with advanced non-small-cell lung cancer (NSCLC).

Methods: Thirty-three consecutive patients with advanced NSCLC that had been pretreated with at least one chemotherapeutic regimen and were responding to chemotherapy following 2 to 3 cycles of treatment, entered the trial from May 2004 to February 2006. Patients received gefitinib at an oral dose of 250 mg once daily for 4 weeks.

Results: Thirty-three patients were evaluable for response and toxicity. The objective response rate was 24.2% (8 of 33) (95% CI, 11% to 42%). The symptom improvement rate was 54.5% (18 of 33) (95% CI, 41% to 69%). The median duration of response was 7 months (95%CI, 4.0 to 13.2 months). The median time to disease progression (TTP) was 6.5 months (95%CI, 0.7 to 16.6 months). The median overall survival time (OS) was 9.8 months (range, 2.1 to 18.0 months), and the actuarial 1-year survival was 36.4%. Toxicity was relatively mild and included only one patient (3.0%) with grade 4 diarrhea, 1 (3.0%) with grade 3 rash, 1 (3.0%) with grade 3 nausea, and 1 with grade 3 vomiting (3.0%).

Conclusion: Preliminary results suggest that sequential administration of gefitinib following a response to chemotherapy may be beneficial for Chinese patients with advanced NSCLC. Further randomized clinical trials are needed.