Extended phase I evaluation of vincristine, irinotecan, temozolomide, and antibiotic in children with refractory solid tumors.

Background: The combination of irinotecan, temozolomide, and vincristine is appealing because of potentially synergistic mechanisms of action and non-overlapping toxicities. This phase I study was designed to determine the toxicity and maximum tolerated dose (MTD) of escalating daily protracted doses of irinotecan given in this combination. With extended accrual, we more fully explored the toxicity of multiple courses at the MTD.