A phase I and pharmacokinetic study of intraperitoneal carboplatin and etoposide.

BACKGROUND: We attempted to determine the maximum tolerated dose and toxicity of etoposide (VP-16) when administered in combination with carboplatin (CBDCA) (300 mg m-2) and administered via the intraperitoneal (IP) route. METHODS AND MATERIALS: A total of 26 patients were treated on this trial. CBDCA was administered at a fixed dose of 300 mg m-2) while VP-16 was started at a dose of 200 mg m-2 and escalated at 50 mg m-2 increments. Both agents were mixed together in 2 litres of 5% Dextrose and administered as quickly as possible into the peritoneal cavity. Pharmacokinetic studies were performed at the maximum tolerated dose (MTD). RESULTS: The MTD for this regimen was CBDCA 300 mg m-2 and VP-16 350 mg m-2. Patients > or = 70 years of age or who had received more than six cycles of previous chemotherapy, tolerated this regimen poorly. The MTD for this group of patients was CBDCA 200 mg m-2 and VP-16 50 mg m-2. Neutropenia was the dose limiting toxicity for both groups. The mean peritoneal/plasma peak ratio was 18.3 for CBDCA and 12.7 for VP-16. The pharmacologic advantage (peritoneal/plasma AUC ratio) was 14.9 for CBDCA and 8.8 for VP-16. Although measurable disease was not a requirement for entrance into this study a response rate of 27% was noted in 15 patients with evaluable disease who had ovarian cancer. CONCLUSIONS: A pharmacologic advantage exists for both CBDCA and VP-16 when administered together via the IP route.