A phase I study with an expanded cohort to assess the feasibility of intraperitoneal carboplatin and intravenous paclitaxel in untreated ovarian, fallopian tube, and primary peritoneal carcinoma: A Gynecologic Oncology Group study.

OBJECTIVE: This study aimed to determine the first-cycle maximum tolerated dose (MTD) of intraperitoneal carboplatin in combination with intravenous paclitaxel and then assess the feasibility of this dose over multiple cycles.

METHODS: Beginning at an intraperitoneal (IP) carboplatin dose area under the curve (AUC) of 5 and a fixed intravenous dose of 175mg/m(2) paclitaxel, patients were entered on a dose-escalating phase evaluating first-cycle dose-limiting toxicity (DLT). After estimating the MTD, cohorts of 20 patients were then entered in an expanded phase to evaluate DLT over four cycles.

RESULTS: Twenty-one patients were entered on the dose-escalating phase. A first-cycle MTD of carboplatin at AUC 8 was tolerated although thrombocytopenia was dose-limiting over multiple cycles. An additional 69 patients were treated in expanded cohorts. Only 5/90 (5.6%) patients discontinued treatment because of a port problem. Four-cycle DLT required de-escalation to a carboplatin AUC of 6, and even at that dose, there were 14 dose-limiting toxic effects in 40 patients (35%). Seven dose-limiting toxicities were due to neutropenia, and 6 were due to grade 3/4 thrombocytopenia. Six cycles of therapy were completed in 75% of eligible patients, but dose adjustments were required.

CONCLUSIONS: The first-cycle MTD did not predict the tolerability of this regimen over multiple cycles. Using an IP carboplatin dose of AUC 6 in combination with paclitaxel, the regimen can be administered with a high completion rate over multiple cycles. Because neutropenia is a frequent DLT, the addition of hematopoietic growth factors may permit a high completion rate while maintaining this dose.