- Any number of prior therapies is permitted; from the start of study treatment, the following time periods must have elapsed: 6 weeks from nitrosourea-containing chemotherapy, 4 weeks from non-nitrosourea-containing cytotoxic chemotherapy (except 23 days from last daily dose of temozolomide taken in a 5 of 28 day regimen), and 2 weeks from last dose of a targeted agent (except 4 weeks for bevacizumab); there is no time period requirement for prior radiation therapy