Both gemcitabine and vinorelbine are new anticancer drugs that have shown activity in the treatment of chemonaive non-small-cell lung cancer (NSCLC). Their role in the second-line treatment of NSCLC is less clear. We conducted a phase 11 study of gemcitabine and vinorelbine combination chemotherapy in patients with NSCLC who had not responded to previous platinum-based chemotherapy, to assess the response and toxicity of this regimen, Seventeen patients were enrolled from September 1998 to February 2001. Treatment consisted of vinorelbine 20 mg/m(2) and gemcitabine 800 mg/m(2) intravenous infusion on days 1, 8, and 15 every 4 weeks. Sixty-five cycles of treatment were given, with a median of four cycles. All patients were evaluable for the toxicity profile, and 16 patients were evaluable for the response rate. The major toxicity was myelosuppression. Grade III or IV neutropenia occurred in 9 patients (52.9%) during treatment. Febrile neutropenia occurred in only I patient (5.9%). Grade III anemia and thrombocytopenia occurred in two and three patients, respectively. Other toxicities were few and mild in severity. After 2 cycles of treatment, 5 of 16 patients (31.3%) had a partial response (95% Cl 8.6-64%). The median time to disease progression was 4.6 months and the median survival was 8.3 months. The 1-year survival rate was 34.3%. In conclusion, gemcitabine and vinorelbine salvage chemotherapy produces a relatively high response rate, low toxicity profile, and good survival in Chinese patients with NSCLC who have not responded to previous platinum-based chemotherapy. Further study is needed to confirm its activity.