Treatment of B-Chronic Lymphocytic Leukemia (B-CLL) With Autologous CD40 Ligand and IL-2-Expressing Tumor Cells

Overview

We would like patients to be in a research study to determine the safety and effectiveness of special cells that may make their own immune system fight their cancer. To do this, we will put a special gene into cancer cells that have been taken from the patients body. This will be done in the laboratory. This gene will make the cells produce interleukin 2 (IL-2), which is a natural substance that may help their immune system kill cancer cells. Additionally, we will stimulate the cancer cells with normal embryonic fibroblasts (cells that develop into normal connective tissues in the body) so that they will make another natural protein called CD40 ligand (CD40L). Studies of cancers in animals suggest IL-2 performs better when mixed with CD40L. Some of these cells will then be put back into the patients body with the goal that they will act like a vaccine and stimulate their immune system to attack the CLL cells. Studies of cancers in animals and in cancer cells that are grown in laboratories suggest that combining substances like IL-2 and CD40L with cancer cells help the body recognize and kill cancer cells. We have already conducted a study similar to this in patients with CLL. In that study, the subjects received about three months of injections (shots). In those subjects we saw some changes in the subject's immune system that might indicate that the modified cells were helping their immune system fight the cancer. However, in most of the subjects this change in the immune system went away after the injections were stopped. In this study we want to see if we can make the change in the immune system last longer by giving more injections over a longer period of time. We hope that this might produce a better response directed at the CLL cells. We will also be looking at the effect on cells called cancer stem cells which grow into the CLL cells we see in the blood. Specifically, this study will allow subjects to receive the injections for up to one year.

Previously, some of the cancer cells taken from the patients body were separated in the laboratory and a specially produced human virus (adenovirus) that carries the IL-2 gene was put into the cells. Adenovirus is a common virus found in human respiratory systems. In its normal state, it can reproduce and cause a respiratory infection. Respiratory illnesses caused by adenovirus infections range from the common cold to pneumonia, croup and bronchitis. This adenovirus has been changed in the laboratory so that it is not likely to reproduce or cause an infection once it is in the patients body. The gene transfer method used in this study tries to add copies of the IL2 gene that increases the immune response against a tumor. The rest of the cancer cells have been stimulated to express on their surface a substance called the human CD40L. These substances (IL-2 and CD40L), already naturally present in the patients body, are meant to help the immune system fight the cancer. In this study, the modified cancer cells will be injected under the skin. The patient will normally have the shots as an outpatient. The patient will receive the first eight (8) shots at 1-2 week intervals. They will then receive four (4) shots at 4 weekly intervals. After these first twelve shots, we will assess how the cancer is responding to these modified cells. If the cancer is not getting worse, the patient may receive an additional six (6) shots. These shots will again be given at 4 weekly intervals. In total, the patient may receive up to eighteen (18) shots over a period of one year. These shots must be given at the Methodist Hospital. Following these injections, the patient will be seen yearly for check-ups for 2 years after the first injection. TESTS DURING AND AFTER EXPERIMENTAL TREATMENT: A complete history and physical examination is necessary before the patient can be enrolled in the study. A physical examination will also be performed each time they are receive a shot of the modified cells. The place on the body where the patient has received their shots will be examined during the physical exam. As mentioned above, the patient will then have yearly checkups for the 2 years after the first injection. After this, we will call the patients physician for updates on the patients health. These calls will be made annually until 5 years after the first injection. To study how the modified cells are working in the body, we will take blood samples prior to each shot, then every four weeks for six months after the last injection, and then 2 years after the first injection. The amount of blood that will be obtained for these tests is approximately 2-3 tablespoonfuls, which is considered to be a safe amount. If the patient has a central line (an IV line that has been placed in a large blood vessel that is meant to be used for long periods of time), the blood will be taken from it, so that extra "sticks" should not be needed. Additional office visits may be necessary to obtain this blood. The maximum total amount of blood to be collected from the patient is 78 tablespoons.