Phase I study of weekly oxaliplatin in relapsed or refractory pediatric solid malignancies

Purpose: To explore feasibility, maximum-tolerated dose (MTD), and recommended dose (RD) for phase II studies of weekly oxaliplatin for the treatment of relapsed or refractory pediatric solid malignancies. Patients and Methods: Eligible patients were 6 months to 21 years old, had a diagnosis of a solid malignancy, and had experienced treatment failure with at least two or more previous lines of therapy. The phase I study was multicentric, open-label, and nonrandomized. It foresaw two phases: a dose-escalation phase (comprising six levels) to find the RD and an extension at the RD to evaluate the cumulative toxicity. Oxaliplatin was administered intravenously over 2 hours on days 1, 8, and 15 of a 28-day cycle. Results: Forty-five patients were enrolled: 29 patients in the dose-escalation phase and 16 patients in the extension at the RD. Median age was 9.5 years (range, 2.8 to 20.0 years) and 7.8 years (range, 1.8 to 19.2 years), respectively. The dose-limiting toxicities during the first treatment cycle were grade 3 (G3) sepsis at 50 mg/m², G3 dysesthesia at 90 mg/m², and G3 dysesthesia and G3 paresthesia at 110 mg/m ², thus the MTD and RD was 90 mg/m². No case of ototoxicity was reported. Stable disease was reported in seven patients (16.3%), and confirmed partial response was observed in two patients (4.7%), one with neuroblastoma and one with osteosarcoma. Conclusion: Oxaliplatin administered in a weekly schedule has an acceptable safety profile, different from cisplatin and carboplatin, and shows activity in children with relapsed or refractory solid tumors, suggesting further investigation in pediatric malignancies.