Clinical trials

The purpose of this research study is to test the safety and effectiveness of a cell therapy at different doses for children and young adults with recurrent or progressive brain tumors. Recurrent/recurred means a tumor that has gone away and then came back. This cell therapy is called B7- H3.CD28Z.CART, referred to as B7-H3 CAR T cells. B7-H3 is a protein that is over-expressed on many tumor cells, making it a good target for cancer cell therapy. The names of the study investigational therapies involved in this study are: * Fludarabine (a type of chemotherapy) * Cyclophosphamide (a type of chemotherapy) * B7-H3 CAR T cells (a type of cellular therapy)

The goal of this research study is to test if a new cell therapy (B7-H3.CD28Z.CART / B7-H3 CAR T cells) is safe and effective in treating children and young adults with solid cancers whose tumors have returned or stopped responding to standard treatments (relapsed or refractory) and have been identified with a B7-H3 marker. The names of the treatment interventions used in this study are: * B7-H3.CD28Z.CART / B7-H3 CAR T cells * Fludarabine * Cyclophosphamide