The purpose of this study was to compare the efficacy and safety profile of docetaxel versus the combination of docetaxel/cisplatin as frontline treatment of patients with advanced or metastatic non-small-cell lung cancer (NSCLC) in a multicenter, randomized, prospective phase III trial. Patients with unresectable stage IIIB or metastatic stage IV NSCLC who had previously undergone no chemotherapy were allocated to receive either docetaxel (100 mg/m2 in a 1-hour intravenous infusion; group A) or the combination of docetaxel (100 mg/m2 day 1) and cisplatin (80 mg/m2 day 2) after adequate hydration (group B). Appropriate premedication was given before docetaxel infusion. All patients in group B received granulocyte colony-stimulating factor (150 microg/m2 subcutaneously) support from days 3 to 9 after treatment. Response and toxicity were assessed by World Health Organization criteria. From March 1999 to November 2001, 302 patients were randomly assigned to receive docetaxel (group A, n = 146) or docetaxel/cisplatin (group B, n = 156). The overall response rate was significantly higher in the combination arm (18% vs. 36%; P < 0.001). However, the 2 groups did not differ in median duration of response, time to progression (TTP), median overall survival (OS), or 1-year survival rate. Drug combination was associated with higher toxicity than single-agent therapy. Both regimens had comparable activity in terms of TTP and OS in chemotherapy-naive patients with advanced NSCLC; however, single-agent therapy had a more favorable toxicity profile.