Phase I and pharmacological study of an oxaliplatin and carboplatin combination in advanced malignancies

Phase I and pharmacokinetic study to determine the maximal tolerated dose and the recommended dose, as well as the optimal sequence of a carboplatin/oxaliplatin combination delivered every 3 weeks.

Patients received either carboplatin [area under the curve (AUC)-based individually calculated dose (starting dose AUC 4 mg.min/ml), 1 h intravenous (i.v.) infusion] followed by oxaliplatin (110 mg/m(2), 2 h i.v. infusion), every 3 weeks, or the reverse sequence.

Sixteen patients were included and only one dose level was assessed. In group A, 10 patients received 23 cycles of carboplatin followed by oxaliplatin. In group B, 6 patients received 20 cycles with the reverse sequence. Delayed recovery from hematological toxicities was treatment-limiting, with mainly moderate thrombocytopenia and neutropenia as dose-limiting toxicities for group A (5 of 10 patients for each) and thrombocytopenia for group B (3 of 6 patients). No febrile neutropenia or grade 3/4 non-hematological toxicity occurred. Pharmacokinetic analysis showed similar mean total platinum AUCs for the two groups: 37.2 +/- 13.7 and 33.6 +/- 9.9 mg.h/l, respectively. One complete response and two partial responses (World Health Organization-International Union Against Cancer criteria, response rate 18.8%) were seen in ovarian, Fallopian and neuroendocrine carcinomas, respectively.

This platinum combination appears feasible and active at the dose of AUC 4 mg.min/ml for carboplatin (Chatelut formula) and oxaliplatin 110 mg/m(2); however, it does not allow a significant increase in platinum dose-intensity delivery.