Clinical trials for glioblastoma multiforme using adenoviral vectors.

Gliomas are among the most lethal malignancies, and constitute more than 70% of all brain tumors. Standard therapy includes surgical resection followed by adjuvant radiotherapy and/or chemotherapy. Malignant gliomas are considered to be non-curable, and the overall prognosis of treatment success is poor with a mean survival of 14.6 months after diagnosis and a 5-year survival rate of 9.8%. The diffusely infiltrating property of the tumors makes total surgical excision often impossible, leading to eventual tumor recurrence. The maximum radiation dose that can be administered to the brain is limited to approximately 60 Gy, which is usually not sufficient to completely eradicate the tumor given that some brain tumors are resistant to radiotherapy. The limitations and short-comings of the available treatment options have provided the impetus to test novel therapy modalities to improve quality of life and increase survival of patients with gliomas.