Twenty-nine patients with non-small cell lung cancer refractory to prior therapy were treated with either vindesine (VDS) alone (3 mg/m2 every week) or the combination of VDS plus cisplatin (DDP) (100 mg/m2 every 28 days). Serial blood and urine samples were collected to assess the pharmacokinetics of VDS and DDP. All patients were evaluable for toxicity and 27 were evaluable for response. No objective antitumor responses were observed. Peripheral neuropathy manifested by paresthesias, muscle weakness, and constipation were observed in 20 treated patients, and hematologic toxicity consisting of thrombocytopenia and/or leukopenia occurred in 18 patients. The plasma and urinary pharmacokinetics of VDS and DDP measured in this study indicate that VDS and DDP do not interfere with each other and that the pharmacokinetics in previously treated and untreated patients are similar. The antitumor responses and degree of toxicity observed in this trial compare unfavorably with previously reported VDS and VDS-DDP trials in previously untreated patients with this disease and suggest that prior exposure to chemotherapy might both decrease antitumor activity and enhance toxicity of these chemotherapeutic agents.