Abstract A prospective phase II study was conducted to determine the response, toxicity and survival rate of lung cancer patients treated with combination paclitaxel and carboplatin in stage IIIB and IV NSCLC. Eligible patients required measurable and/or evaluable diseases; performance status (ECOG) 0–2; no previous chemotherapy; adequate hepatic, renal and bone marrow function. Paclitaxel was administered at a dose of 200 mg/m 2, 3 h infusion, followed by carboplatin at an AUC of 6. Treatment was repeated every 3 weeks for six courses. G-CSF 5 microgram/kg was subcutaneously injected during subsequent courses if there was grade 3–4 leucopenia or granulocytopenia in the previous course. From April 1996 through July 1997, 53 patients were enrolled; all are assessable for toxicity and response. The median age was 56 years (range, 20–77 years). Sixty four percent were male, 64% had adenocarcinoma and 62% had stage IV disease. Two hundred and seventy two courses were administered; 36 patients (68%) completed all six cycles. Two patients achieved a complete response (4%) and 27 patients achieved a partial response (51%), for an overall response rate of 55%. Sixteen patients had stable disease (30%) and 8 patients had progressive disease (15%). The median progression free survival time for all patients, stage IIIB and stage IV patients was 28 weeks (range, 18–37 weeks), 31 weeks (range 21–41 weeks) and 22 weeks (range 16–29 weeks), respectively. The median survival time and 1 year survival rate for all patients was 55 weeks (range, 51–59 weeks) and 55%, respectively. Stage IIIB patients had better median survival time and 1-year survival rate than stage IV patients (75 vs. 46 weeks, P=0.007; 80% vs. 42%, P=0.003). Grade 3 and 4 granulocytopenia, anemia and thrombocytopenia were observed in 25, 3, and 1%, respectively, of the 272 courses administered. G-CSF was required in 28% of the 272 courses. There were four episodes of fibrile neutropenia (1.5%), three episodes of angina pectoris (1%) and one episode of anaphylaxis (0.4%). Other common toxicities, generally mild, included myalgia, arthralgia, peripheral neuropathy and asthenia. Most toxicities showed cumulative effect. Paclitaxel plus carboplatin is a moderately active regimen in advanced NSCLC. Toxicites of this regimen are well tolerated.