I. INTRODUCTION 
This study is designed primarily to evaluate the safety of using a virus created in the 
laboratory as part of a treatment for tumors of the brain. In addition, the effect of the 
treatment on the tumor will be carefully monitored. 
You are being asked to voluntarily participate in this research project to be carried out 
at Baylor College of Medicine and The Methodist Hospital. We plan to enroll approximately 
20 people into this study over several years. All research projects that are carried out in 
these institutions are governed by the rules of the Baylor College of Medicine and the 
Federal Government. Participation in these studies is entirely voluntary. You may gain no 
personal benefit from participating in this study; however, knowledge will be gained which 
will help to develop new treatments that may benefit others with similar diseases. 
Withdrawal from this study or refusal to participate for any reason may be done at any time 
and will not in any way affect the care that you receive. 
You are being asked to read the consent form carefully. It will describe the nature of 
the study and the risk, or inconveniences, that it may present to you. Please do not hesitate 
to ask any questions or discuss any issues about this study with your physician, the 
scientists involved in this study, or others you feel would be helpful. If you decide to 
participate in this study, you will be given a copy of this form. 
Summary 
There is no effective treatment for malignant brain tumors that recur following surgery, 
radiation therapy, and/or chemotherapy. Therefore, we have developed a new experimental 
approach, for the treatment of recurrent brain tumors, that takes advantage of knowledge 
gained in the fields of virology, genetics and gene therapy. The purpose of this study is to 
gain information about whether or not this new approach is safe and effective in treating 
human brain tumors. Although the findings in animals are encouraging, you will be one of 
the first humans to receive this investigational treatment for brain tumors. You have been 
offered this opportunity because, despite standard treatments including surgery, radiation 
therapy and/or chemotherapy, your tumor has reoccurred. After speaking with your doctor 
you may elect to continue with standard treatment, participate in this study, or discontinue 
all treatments. While we hope to gain information on the usefulness of this approach in 
humans, we cannot know whether your tumor will get smaller as a result of this treatment. It 
is possible that this treatment may make you worse. 
What Is Gene Therapy for Brain Tumors? 
We will attempt to change the genetic material of your brain tumor cells by inserting a 
viral gene, which is a small piece of the basic structure of the virus, into the tumor cells. The 
gene to be inserted comes from the virus that causes cold sores. The gene is called the tk 
gene. It directs the cell into which it is inserted to make a protein call thymidine kinase which 
the cells in turn can use to metabolize (break down) other substances in the cell. The way 
we will transport the tk gene into the tumor cells is to use a "vehicle" to carry the tk gene into 
the cells. An example is that if you want to move a passenger you need to put him in a car. 
The vehicle (or car) in this case is a different virus -- an adenovirus. This virus is a common 
human adenovirus that gives people sore throats. We removed a portion of the virus' 
genetic material so that it cannot cause infections. We call this vehicle a "vector." In place of 
the removed genetic material the tk gene (the passenger) was inserted into the vector. Now 
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