Phase I and pharmacokientic study of the new vinca alkaloid vinflunine administered as a 10-min infusion every 3 weeks in patients with advanced solid tumours

Background: Vinflunine is a novel vinca alkaloid obtained by semi-synthesis using super-acidic chemistry to selectively introduce two fluorine atoms at the 20' position of vinorelbine. In human tumour xenografts, vinflunine showed definite antitumour activity in seven out of 11 tumours tested compared with three out of 11 for vinorelbine. Patients and methods: In this phase I study, vinflunine was administered to 31 patients with advanced malignancies as a 10-min i.v. infusion every 3 weeks according to an escalating schedule of doses between 30 and 400 mg/m(2). Results: Pharmacokinetic parameters and toxicities were assessed and, at 400 mg/m2, three out of five patients experienced dose-limiting toxicity. At the maximum tolerated dose (MTD), i.e. 400 mg/m(2), the toxicity profile of vinflunine consisted mainly of mucositis. constipation and neutropenia of short duration. Vinflunine area under the curve increased as a proportion of the administered dose whereas no saturation of elimination was observed. Conclusion: The MTD of vinflunine was achieved at 400 mg/m2 every 3 weeks. According to protocol rules, the recommended dose was established at 350 mg/m(2), A preliminary assessment of first patients included in early phase II trials led to reduction of the recommended dose to 320 mg/m2 every 3 weeks for further development of vinflunine. Three partial responses (two in breast carcinoma. one in renal cell carcinoma) suggest that activity is likely to be seen in less heavily pretreated patient populations.