- Any other prior therapy directed at the malignant tumor, including chemotherapy, biological/targeted (non-cytotoxic) agents, and immunologic agents, must be discontinued at least three weeks prior to registration; chimeric or human or humanized monoclonal antibodies (including bevacizumab) or vascular endothelial growth factor (VEGF) receptor fusion proteins (including VEGF TRAP/aflibercept) must be discontinued for at least 12 weeks prior to registration