2.4 Gene Transfer into Human Subjects 
The methods we will utilize to transfer cytokine genes into cells are virtually identical to those employed 
in previously approved human gene transfer studies in which tumor infiltrating lymphocytes (TELs) were 
modified by retroviral gene mediated transduction and administered to cancer patients (14). In this earlier 
Phase I study of retroviral mediated gene transfer, TELs were genetically modified to express the 
neomycin phosphotransferase (neo^) gene. Following intravenous infusion, polymerase ch^ reaction 
analysis consistently demonstrated the presence of genetically modified cells in the circulation for as long 
as two months after administration. No infectious retroviruses were identified in these patients and no 
side effects due to gene transfer were noted in any patients (14). Additional Phase I clinical protocols 
employing similar retroviral gene transfer methods have recently been approved by the Recombinant 
DNA Advisory Committee (RAC). Our Phase I study of human cancer patients will utilize the same gene 
transfer methods and safety testing procedures employed in these previously approved investigations. 
2.5 Single Patient IL-2 Gene Therapy of Glioblastoma 
2.5.1. Patient History 
We have treated one glioblastoma multiforme (GBM) patient with IL-2 gene therapy. The patient is a 52 
year old female with GBM of the right temporal lobe diagnosed in 1/92. She was initially treated with 
surgical resection, conventional radiotherapy and PCV chemotherapy (procarbazine, CCNU and 
vincristine). Nine months later, a second resection was performed for tumor recurrence. Tumor 
pathology revealed a GBM at re-resection. The patient's tumor progressed after experimental treatment 
with accutane and with an I^^ ^ radioisotope labeled anti-tenacin monoclonal antibody. Subsequently, the 
patient was treated with experimental stereotactic radiation therapy designed to encompass the site of 
tumor involvement. 
2.5.2. IL-2 Gene Therapy 
EL-2 gene therapy was initiated in January 1993, approximately one year after the first tumor resection. 
The patient received nine subcutaneous injections at 2 to 4 week intervals with either autologous, 
irradiated EL-2 transduced tumor cells or a mixture of irradiated tumor cells and irradiated DL-2 
transduced fibroblasts. A tenth iinjection was performed approximately 3 months after the ninth 
inoculation. Two IL-2 retroviral vectors were employed in this study. The retroviral vector 
DC/AD/R/IL-2 (kindly provided by Dr. Bemd Gansbacher) utilized an adenosine deaminase promoter to 
drive IL-2 expression while the retroviral vector GlNaCvi2.23 (kindly provided by Genetic Therapy Inc.) 
employed a c^omegalovirus promoter (Figure 1). 
Figure 1 
Retroviral Vector DC/ADA/RyiL-2 
LTR 
[6181 
Retroviral Vector G1NaCvi2.23 
Recombinant DNA Research, Volume 19 
