Main

Inclusion Criteria:

- Age 19 years and older

- Phase Ib: Histologically confirmed recurrent glioblastoma multiforme or gliosarcoma
(recurrent anaplastic astrocytoma also included in phase Ib) that is progressive
despite previous radio- or chemotherapy

- Phase II: Histologically confirmed recurrent glioblastoma multiforme or gliosarcoma
that is progressive despite previous radio- or chemotherapy

- Enhancing brain tumor measures at least 1.0 cm in diameter and evaluable by MRI
within 14 days of G207 administration (and proposed area of study drug inoculation
appears to be resectable en bloc--for phase Ib only)

- Steroid regimen stable for at least 1 week prior to G207 inoculation

- Karnofsky Performance Status 70% or greater

- Failed external beam radiotherapy of at least 5000 cGy 4 weeks or longer prior to
G207 administration

- Candidate for brain tumor resection

- Females: negative urine pregnancy test within 24 hours prior to G207 administration

- Willing to use effective barrier birth control

- Able to give informed consent

Main Exclusion Criteria:

- Multiple (more than one) intracranial malignant glioma lesions

- Documented extracranial metastases

- Laboratory test values (CBC, platelets, clinical chemistry, liver and renal function
tests) outside protocol specified limits

- Chemotherapy, cytotoxic or immunotherapy within 6 weeks of G207 administration

- Any contraindication for undergoing MRI such as pacemakers, infusion pumps, aneurysm
clips, metal prosthesis, former welders etc.

- Surgical resection within 4 weeks of G207 administration

- Pregnant or nursing females

- History of any of the following: HIV seropositive (historical or known); other
investigational agents or vaccinations within 30 days; encephalitis, multiple
sclerosis or other CNS infection; prior gene transfer therapy or prior therapy with a
cytolytic virus of any type

- Any of the following concurrent conditions: evidence of active herpes infection;
requires antiviral therapy for HSV at baseline; previous history or current diagnosis
of other cancer except curative cervical cancer in situ or basal or squamous cell
carcinoma of the skin; active uncontrolled infection, granulocytopenia, any unstable
or severe medical condition that precludes surgery; alcohol or other substance abuse