PURPOSE The aim of the study was to evaluate the activity of vinorelbine (VNLB) in a population of advanced ovarian cancer patients, with particular attention to defining its role in platinum-resistant disease. PATIENTS AND METHODS Thirty-three patients were recruited and treated with VNLB 25 mg/m2 intravenously (IV) weekly. the median age was 53 years, performance status 0 to 2, and number of previous chemotherapy regimens two (range, one to five). Twenty-four patients were platinum-resistant; the remaining nine either were platinum-sensitive (four cases) or had undetermined sensitivity (five cases). RESULTS The mean delivered dose-intensity of VNLB was 67% of the planned level, because 60% of the cycles were delayed due to neutropenia or anemia. Four partial responses (PRs) and one complete response (CR) were observed, for an overall response rate of 15% (95% exact confidence interval, 5.1% to 31.9%). All the responses occurred in the subgroup of 24 platinum-resistant cases, in whom the response rate was 21% (95% exact confidence interval, 7.1% to 42.1%). Seven patients became stabilized on VNLB, and 27% of the cases showed a reduction in serum cancer antigen 125 (CA 125) levels. G3/G4 side effects consisted of neutropenia, anemia, and worsening of preexisting peripheral neuropathy. No treatment-related deaths occurred. CONCLUSION VNLB led to a 21% response rate in the population of heavily pretreated and platinum-resistant ovarian cancer patients. Further studies of VNLB alone or in combination with taxanes are warranted in patients with less pretreatment.