MTOR and glioblastoma: Regarding recurrent glioblastoma, clinical trials have considered erlotinib alone207–210 or a combination of erlotinib and carboplatin (chemotherapy),211 erlotinib and sorafenib (Raf inhibitor),212 or erlotinib and mTOR inhibitors (sirolimus and temsirolimus).213,214 These trials have not resulted in positive outcomes, with the average PFS of patients ranging from 6–11 weeks.