Phase I clinical and pharmacokinetic study of trabectedin and cisplatin in solid tumours.

AIM OF THE STUDY: To define the maximum tolerated dose (MTD) and toxicity of trabectedin (T) and cisplatin (C) given on days 1 and 8 every 3 weeks to adult patients with advanced solid tumours. Plasma pharmacokinetics at cycle 1 and a preliminary anti-tumour activity assessment in ovarian and non-small cell lung cancer (OC, NSCLC) were secondary objectives. METHODS: In the dose finding part (DFP) of the study the dose of T given at each administration was escalated by 100 microg/m(2) increments from 300 microg/m(2) up to the MTD, with a fixed dose of C of 40 mg/m(2). The recommended dose (RD) was assessed in the previously treated and untreated OC and NSCLC patients in the expansion of the RD (ERD) part of the study. T was administered with corticosteroids pre-medication as 3-h infusion and C as 30-min infusion. RESULTS: Thirty-nine patients were treated in the DFP and 10 in the ERD. The MTD of T was 700 microg/m(2) due to dose-limiting neutropaenia and the RDs in the previously treated/untreated patients were 500 and 600 microg/m(2), respectively. Most common toxicities were nausea/vomiting (67%), asthenia/fatigue (55%) and reversible ASAT/ALAT elevation (51%). Time to recovery from myelosuppression was dose-dependent and treatment could be repeated after > or = 4 weeks in the majority of patients at 600 microg/m(2). Confirmed partial responses were observed in 4 of 13 evaluable OC patients and in 1 with uterine leiomyosarcoma. No pharmacokinetic interaction was observed. CONCLUSION: The administration of T and C on days 1 and 8 resulted in prolonged neutropaenia requiring treatment delay. The evaluation of a single every 3 week schedule is worthwhile because of the hints of anti-tumour activity observed in OC.