Because the patient will receive cells with a new gene in them, they will be followed for a total of 15 years to see if there are any long-term side effects of the gene transfer.
Before the conditioning treatment for the transplant, we collected 30 mL (6 teaspoonfuls) of blood from the patient, which we made into a cell line that grows in the laboratory by mixing the blood with a virus called EBV. Some of the cells from this blood were mixed with T cells from the blood stem cell donor, to stimulate cells that might cause GvHD. We then added an investigational agent called RFT5-dgA. The RFT5-dgA helped to get rid of donor T cells that might cause GvHD. To get iCasp9 into the remaining T cells, we have to insert the iCasp9 gene into these cells. This is done with a virus called a retrovirus that has been made for this study, and will carry the iCasp9 gene into the T cells. The virus also has another gene called CD19, which will make the cells express the CD19 protein on their surface. We will not inject the virus directly into the patient, but only into the special T cells we have made in the laboratory. After we have put the virus into the cells, we will select the T cells that have CD19 on their surface, so we know these cells will also have the iCasp9 gene. We will perform tests on the specially treated cells before giving them to the patient, to ensure they only carry the iCasp9 gene, and not the virus itself. This should ensure that no virus can come out of the cells and infect other cells in the body.
TREATMENT PLAN:
To prepare the body for transplantation, the patient will be given high-dose chemotherapy. Further discussion of the treatment plan for the stem cell transplant will be discussed with the patient separately, and they will sign a separate consent form.
If the patient is doing well after the transplant, and they do not have serious GvHD, they will be eligible to receive the special T cells from Day 30 to 90 post-transplant. The specially selected and treated T cells will be given by vein, once. The cells will be given between Day 30 and day 90 after the patient receives their stem cell transplant. We will give special medicines before the IV starts to help prevent allergic reactions that might occur. Because there is a possibility that the specially treated T cells can cause or worsen GvHD, we will not be able to give these cells if the patient already has significant GvHD.
If the patient develops GvHD after being given the specially treated T cells, we will prescribe the new drug that has been shown to kill cells carrying iCasp9. The drug's name is AP1903. It has been tested in normal healthy volunteers, and has not caused any bad effects, but it is not approved by the FDA. Although the drug is not approved by the FDA, the FDA has allowed us to use the drug for this study. This drug will be given as a 2-hour intravenous infusion. We will take 10 mL (2 teaspoonfuls) of blood on days 2, 4, 7 and 14 after the infusion to check if the drug has been successful in killing the specially treated cells. If the patient has mild GvHD, and if the GvHD does not get better with AP1903, we will give the patient additional medicines that are usually used to treat GvHD. If the patient has serious GvHD, we will immediately give additional medicines that are usually used to treat GvHD, as well as AP1903. In some cases though, GvHD does not respond to treatments.
