Superior in vivo experimental antitumour activity of vinflunine, relative to vinorelbine, in a panel of human tumour xenografts.

The antitumour activity of vinflunine, 20',20'-dichloro-3',4'-dihydrovinorelbine, a fluorinated Vinca alkaloid obtained by reaction in superacid media, was evaluated in comparison with vinorelbine against a series of subcutaneously-implanted human tumour xenografts. The tumours studied were established from bladder (BXF1299), pancreas (PAXF546), kidney (RXF944LX), colon (DLD-1, HT-29, TC37), central nervous system (SF-295), small cell lung (NCI-H69) and prostate (PC-3). Vinflunine or vinorelbine was administered as four weekly intraperitoneal treatments, within dose ranges of 5-80 or 0.63-10 mg/kg/injection, respectively. The overall antitumour activity of vinflunine was superior to that of vinorelbine. Vinflunine showed high activity against RXF944LX and NCI-H69 xenografts and moderate activity against PAXF546, PC-3 and TC37 tumours, achieving an overall response of 64%. This contrasts with a 27% response with vinorelbine, which proved only moderately active against RXF944LX and TC37 xenografts. These results confirm and extend our previous report of the broad spectrum of in vivo antitumour activity of vinflunine and reinforce its potential as a valuable addition to current chemotherapeutic agents.