Phase II studies have suggested that weekly paclitaxel has a higher response rate and better toxicity profile than the conventional schedule of once every 3 or 4 weeks. Our aim was to evaluate the efficacy of weekly paclitaxel plus cisplatin (PC) vs vinorelbine plus cisplatin (VC) in chemonaïve non-small-cell lung cancer (NSCLC) patients. From October 2000 to May 2002, 140 patients were enrolled. The treatment dose was P 66 mg m(-2) intravenous infusion (i.v.) on days 1, 8, and 15, and C 60 mg m(-2) i.v. on day 15, or V 23 mg m(-2) i.v. on days 1, 8, and 15, and C 60 mg m(-2) i.v. on day 15, every 4 weeks. In all, 281 cycles of PC and 307 cycles of VC were given to the patients in the PC and VC arms, respectively. There were 26 partial responses and one complete response (overall 38.6%) in the PC arm, and no complete responses, but 27 partial responses (overall 38.6%) in the VC arm. Myelosuppression was more common in the VC arm (P<0.001). Peripheral neuropathy and myalgia were significantly more common in the PC arm (P<0.001). The median time to disease progression was 6 months in the PC arm and 8.4 months in the VC arm (P=0.0344). The median survival time was 11.7 months in the PC arm and 15.4 months in the VC arm (P=0.297). We concluded that weekly PC is not suggested for NSCLC patients due to the relatively shorter progression-free survival and more common nonhaematological toxicities. British Journal of Cancer (2004) 90, 359-365. doi:10.1038/sj.bjc.6601526 www.bjcancer.com