To define the activity of an individually escalated dacarbazine (DTIC) dose combined with interferon-alpha-2a (IFN), granulocyte-colony stimulating-factor (G-CSF) and ondansetron, 20 patients (pts) with metastatic melanoma were treated with DTIC, ondansetron 8 mg iv, G-CSF 300 micrograms sc and IFN 9 MU sc. Treatment was performed every 21 days to a maximum of 6 courses. DTIC dose was escalated with 250 mg/m2 in case of acceptable toxicity to 1250, 1500 and 1750 mg/m2 in (projected/realized), 14/19, 8/11 and 0/5 pts, respectively. Dose escalation prohibiting toxicities were thrombocytopenia (10 pts), leukopenia (9 pts), and nausea/vomiting (2 pts). Four partial remissions were observed, for a response rate of 20% (95% confidence interval, 6 to 44%). Duration of responses was 1, 2, 3 and 3 months. Median overall survival was 8 months.