Pediatric phase I trial of carboplatin: a Childrens Cancer Study Group report.

Carboplatin is one of a series of cisplatin analogs now undergoing clinical investigation. Phase I and II trials in adults demonstrate activity in a number of human cancers and less toxicity than might be expected with the parent compound. This phase I trial was undertaken to establish the maximum tolerated dose and the recommended phase II dose in children treated by a 1-hour iv infusion every 4 weeks. Twenty-nine patients with recurrent or progressive tumor were entered in this study at the Children's Hospital of Los Angeles and Children's Memorial Hospital in Chicago between April 12, 1983, and November 27, 1984. Beginning with a dose of 350 mg/m2 (about 80% of the adult phase II dose), we escalated the dose in groups of patients to 670 mg/m2; dose-limiting myelosuppression was encountered at this dose. Fifty-seven infusions are at least partially evaluable for toxicity. Asymptomatic hypomagnesemia, hypocalcemia, and ototoxicity were observed infrequently, and nausea and vomiting were mild. One patient with a mixed glioma of the posterior fossa achieved a good partial response lasting 9 months. Stable disease for greater than or equal to 6 months was observed in three patients: one each with ependymoma, brain stem glioma, and spinal cord astrocytoma. The recommended pediatric phase II dose is 560 mg/m2 given as a 1-hour iv infusion every 4 weeks.