New treatments are greatly needed for patients with recurrent glioblastoma. Metronomic temozolomide is a standard treatment option but has, at best, modest activity. The nanoliposomal irinotecan may be much more active than the parent compound irinotecan since nanoliposomal irinotecan's ability to cross the blood brain barrier is improved. This phase I study will establish the MTD of the combination of nanoliposomal irinotecan in combination with temozolomide safety and preliminary clinical efficacy of the combination of nanoliposomal irinotecan and metronomic temozolomide.