Phase I clinical study of a novel lipophilic platinum complex (SM-11355) in patients with hepatocellular carcinoma refractory to cisplatin/lipiodol.

SM-11355 is a platinum complex developed to treat hepatocellular carcinoma (HCC). It is administered via the hepatic artery, using a carrier, lipiodol, that consists of ethyl esters of iodized poppy seed oil. We have performed a phase I clinical trial of an SM-11355-lipiodol formulation in 11 HCC patients, in order to investigate the maximum allowable dose and to maximize the efficacy and safety of the drug in the treatment of HCC. The SM-11355 arterial infusion suspension was administered at doses of 6, 12 and 20 mg ml(-1) in a maximum lipiodol volume of 6 ml. An antitumour efficacy rating of complete response was achieved for one patient and a partial response rating was achieved for a second patient, giving an overall response rate of 18.2%. Anorexia, nausea and vomiting, pyrexia, thrombocytopenia and increases in AST, ALT and total bilirubin were observed as adverse effects, but each was transient and each patient had recovered completely by 4 weeks after drug administration. Hence, we concluded that the maximum allowable dose was not reached in this study. Overall, our results suggest that SM-11355 is effective in treating HCC and we suggest that the dose for early phase II trials should be 20 mg ml(-1).