Bevacizumab With or Without Trebananib in Treating Patients With Recurrent Brain Tumors

This partially randomized phase II trial with a safety run-in component studies the side effects and how well bevacizumab given with or without trebananib works in treating patients with brain tumors that have come back (recurrent). Immunotherapy with monoclonal antibodies, such as bevacizumab, may induce changes in the body\'s immune system and interfere with the ability of tumor cells to grow and spread. Trebananib may stop the growth of tumor cells by blocking blood flow to the tumor. It is not yet known whether giving bevacizumab together with trebananib is more effective than bevacizumab alone in treating brain tumors.