This phase II trial studies how well cabozantinib-s-malate works in treating younger patients with sarcomas, Wilms tumor, or other rare tumors that have come back, do not respond to therapy, or are newly diagnosed. Cabozantinib-s-malate may stop the growth of tumor cells by blocking some of the enzymes needed for tumor growth and tumor blood vessel growth.
I. To determine the objective response rate (complete response + partial response) of cabozantinib-s-malate (XL184) in children and young adults.
I. To further define XL184 related toxicities in pediatric, adolescent and young adult patients.
II. To further define XL184 pharmacokinetics in the pediatric and adolescent patients.
I. To estimate 1-year time to progression, progression free survival (PFS) and overall survival for each stratum, and if feasible to compare to historical controls.
II. To assess the effect of XL184 on patients’ immune cell subsets.
III. To obtain tumor tissue (snap frozen, formalin-fixed and paraffin-embedded [FFPE] blocks, or unstained slides) from diagnosis, recurrence, or both, for possible future studies.
Patients receive cabozantinib-s-malate orally (PO) once daily (QD) on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.
After completion of study treatment, patients are followed up at 30 days, every 6 months for 1 year and then annually for up to 5 years.