- Patient has recovered from toxicity of prior therapies; an interval of at least 12 weeks must have elapsed since the completion of radiation therapy; at least 6 weeks since the completion of nitrosourea-containing chemotherapy regimen; and at least 4 weeks since the completion of a non-nitrosourea-containing cytotoxic chemotherapy regimen; if a patient's most recent treatment was with a targeted agent only; and s/he has recovered from any toxicity of this targeted agent, then a waiting period of only 2 weeks is needed from the last dose and the start of study treatment, with the exception of bevacizumab where a wash out period of at least 4 weeks is required before starting study treatment