This study has three parts:

1. Screening Period (about 10 days):
You will go to the clinic for tests like a brain scan (MRI), blood tests, heart check (EKG), and physical and brain exams.

2. Study Dosing Period:
You will get a medicine called BRiTE through a small tube in your vein using a portable pump. It will run for 4 days. Then, you will not get any medicine for 24 days. This is called one cycle. You will go through 3 cycles like this.

3. Follow-Up Period:
Doctors will keep checking on you with exams, blood tests, heart checks, and brain scans. You will visit the clinic every 8 weeks to make sure everything is going well.

This study is for people who have a very serious kind of brain cancer called glioblastoma. It must be either newly found or has come back again. Doctors call this Grade 4 glioblastoma, which means it is the most severe kind.

People in this study must:

• Be 18 years old or older.
• Have a serious brain cancer called Grade 4 glioblastoma in a part of the brain called the supratentorial region.
• Have a special change in their cancer called the EGFRvIII mutation.

If they were just diagnosed, they must have had surgery to remove the tumor.
If their cancer came back, it must be confirmed by a scan or test and be no bigger than 4 centimeters.

They cannot join the study if:

• They have HIV and low immune cell counts.
• They have an active hepatitis B infection.
• They have an autoimmune disease that needed strong medicine in the past 3 months.

This study is trying to find the safest and best amount of a new medicine called BRiTE for people who have a serious brain cancer called glioblastoma. Some people are newly diagnosed, and some have had the cancer come back.
BRiTE is a kind of medicine called immunotherapy. It helps the body's immune system work better. It helps special cells called T cells find and destroy cancer cells.