Trial Information

Phase I Study of Anti-Human CD45 Monoclonal Antibodies in Patients With Advanced Leukemia Prior to Allogeneic Stem Cell Transplantation (ADVL)

Patients are given high doses of chemotherapy before receiving a stem cell transplant to
keep their immune system from rejecting the donor stem cells and to kill any diseased cells
that remain in the body. To try and improve on the results of transplants that use high dose
chemotherapy alone, we are adding an agent called anti-CD45 to the treatment prior to the
stem cell transplant. Anti-CD45 is an antibody that specifically finds and destroys leukemia
cells.

Patients will receive the anti-CD45 with high dose chemotherapy (including Ara-C and
Cyclophosphamide) and radiotherapy. Patients will also receive Mesna which is a drug that
helps prevent bladder damage which can be caused by the cyclophosphamide. High dose
radiotherapy is also known as Total Body Irradiation or TBI.

Patients will receive the anti-CD45, high dose chemotherapy, and high dose radiotherapy
before the stem cell transplant. We expect participation in this study will last 2 years.

A summary of the treatment follows:

- Day - 7: Ara-C, Cyclophosphamide, Mesna

- Day - 6: Ara-C, Cyclophosphamide, Mesna

- Day - 5: Ara-C, Anti-CD45

- Day - 4: Anti-CD45, TBI

- Day - 3: Anti-CD45, TBI

- Day - 2: Anti-CD45, TBI

- Day - 1: TBI

- Day 0: Stem Cell Infusion (transplant)