Safety and Effectiveness Study of G207, a Tumor-Killing Virus, in Patients With Recurrent Brain Cancer

This clinical trial will study the safety and effectiveness of an engineered herpes virus, G207, administered directly into the brain of patients with recurrent brain cancer. G207 has been modified from the herpes virus that causes cold sores (called herpes simplex virus type 1 or HSV-1). G207 has been designed so that it should kill tumor cells, but not harm normal brain cells. G207 has been shown to be safe in animal testing completed to date and in previous studies in patients with brain tumors. This is a phase Ib/II study. In the phase Ib portion of the study, patients will receive G207 at a dose that is higher than tested in previous human studies. Patients will initially receive 15% of the assigned dose injected directly into the brain tumor. Approximately two days later, as much of the tumor as possible will be surgically removed, and more G207 will be injected into the brain tumor bed. Patients will be monitored, and medical tests will be done at specific study timepoints. The phase II portion will begin only if there are no safety concerns in the phase Ib portion. The goals of the phase II portion of the study are to determine the safety of G207 and to study patient survival at six months after G207 dosing. In the phase II portion of the study, patients will receive a single dose of G207 at the highest dose determined to be safe in the phase Ib portion of the study. The tumor will be removed, and G207 will be injected into any remaining tumor tissue in the brain tumor bed. Patients will be closely monitored, medical tests will be performed at specific study visits, and survival will be evaluated.