The purpose of this Phase 1/2, open-label, single-arm study is to determine the safety and the maximal tolerated dose (MTD) of VAL-083 in patients with recurrent malignant glioma. Pharmacokinetic (PK) properties will be explored and tumor responses to treatment will be evaluated.  Recurrent glial tumors of the brain continue to be one of the most challenging malignancies to treat. Median survival for patients with recurrent disease is approximately 6 months for glioblastoma multiforme. Bevacizumab is used for treatment of recurrent disease; however patients who fail bevacizumab do not have many treatment options.

Metastases to the brain are the most common intracranial tumors in adults and occur ten times more frequently than primary brain tumors. It is estimated that 8 - 10% of cancer patients may develop symptomatic metastatic tumors in the brain. Systemic therapy is rarely used for primary treatment of brain metastases because many tumors that metastasize to the brain are not chemosensitive or have been already heavily pretreated with potentially effective agents, and poor penetration through the blood brain barrier is an additional concern.

Dianhydrogalactitol (DAG) rapidly penetrates both the cerebrospinal fluid (CSF) and the blood-brain barrier and accumulates in brain tissue. Clinical study of DAG in patients with GBM or with progressive secondary brain tumors is warranted. Patients with secondary brain metastases were allowed to enroll into the current protocol in Cohorts 2 and 3; however, enrollment ceased with Amendment 5 and will not be continued beyond Cohort 3.

This study will utilize a standard 3 + 3 dose escalation design, until the MTD or the maximum specified dose has been reached. In Phase 2, additional patients with GBM will be treated at the MTD (or other selected optimum Phase 2 dose) to measure tumor responses to treatment.