The purpose of this study is to find out what effects, good or bad, pazopanib (GW786034),
National Service Center (NSC) # 737754, has on children, adolescents and young adults
between 12 months and less than or equal to 18 years of age with relapsed or refractory
rhabdomyosarcoma, non rhabdomyosarcomatous soft tissue sarcoma, Ewing sarcoma, relapsed or
refractory osteosarcoma, neuroblastoma (measurable and/or evaluable), or hepatoblastoma.
This is a two-stage open label phase II trial of pazopanib in children, adolescents and
young adults with recurrent or refractory solid tumors. Eligible subjects will receive
pazopanib daily as an oral tablet (450 mg/m^2/dose) or as a powder for suspension (225
mg/m^2/dose) in 28 day cycles. The maximum dose to be administered daily for tablets is 800
mg and for suspension 400 mg. Subjects will be closely monitored with clinical and
laboratory observations for side effects. Response to treatment will be evaluated using
appropriate imaging studies. In the absence of severe toxicity or progressive disease,
subjects may continue receiving pazopanib.