This Phase II clinical trial is an open label, single arm, multicenter study of the combination of intravenously administered SGT-53 and oral temozolomide in patients with confirmed glioblastoma who have proven tumor recurrence or progression. The objective of this trial is to assess 6 month progression free survival (PFS), overall survival (OS), anti-tumor activity, safety and possibly to evaluate, nanoparticle delivery to tumor site, and the induction of apoptosis in the tumor..