The purpose of this study is to see if a new treatment could help patients who have osteosarcoma that does not go away with treatment (is refractory) or comes back after treatment (is recurrent).This study is testing a combination of study therapies, UB-TT170 and genetically modified chimeric antigen receptor T lymphocyte (CAR T) cells, which work together in a way that is different from chemotherapy.
In this study, researchers will take some of your blood and remove the T cells in a process called "apheresis". Then the T cells are taken to a lab and changed to CAR T cells that recognize the flags from UB-TT170. Once researchers think they have grown enough CAR T cells, called antiFL(FITC-E2) CAR T cells, to fight your cancer, you may get some chemotherapy to make room in your body for the new cells and then have those cells put back in your body.
A few days after the you get your CAR T cell infusion you will start to get infusions of UB-TT170, with the dose slowly increasing for the first few infusions until you have reached a maximum dose that you will get on a regular schedule. The UB-TT170 will attach to your tumor cells and flag them so that they attract the CAR T cells. When the CAR T cells see the labeled tumor cells they can kill the tumor cells.
The active part of the study lasts about 8 months, and if you get the CAR T cell infusion you will be in long-term follow-up for 15 years.