Vinblastine 5-day continuous infusion in metastatic renal-cell carcinoma was evaluated in a Phase II trial. The dosage varied from 1.4 to 1.6 mg/m2/day every 3 weeks according to previous treatment and performance status (PS). From September 1983 to January 1986, 25 consecutive patients entered the study; 21 were evaluable for response and 23 were evaluable for toxicity. The median number of cycles administered was three (range, one to six). One complete response (liver) lasting 5 months, one partial response (lung) lasting 3 months, 12 cases of stable disease, and seven progressions were noted. Toxicity (WHO criteria) was relevant and mainly hematological: one treatment-related death occurred. Vinblastine continuous infusion did not demonstrate significant antineoplastic activity against metastatic renal-cell carcinoma.