University of California, San Francisco – Chronic Myeloid Leukemia

Access Program Information

This protocol provides expanded access to bone marrow transplants for children who lack a
histocompatible (tissue matched) stem cell or bone marrow donor when an alternative donor
(unrelated donor or half-matched related donor) is available to donate. In this procedure,
some of the blood forming cells (the stem cells) are collected from the blood of a partially
human leukocyte antigen (HLA) matched (haploidentical) donor and are transplanted into the
patient (the recipient) after administration of a “conditioning regimen”. A conditioning
regimen consists of chemotherapy and sometimes radiation to the entire body (total body
irradiation, or TBI), which is meant to destroy the cancer cells and suppress the
recipient’s immune system to allow the transplanted cells to take (grow). A major problem
after a transplant from an alternative donor is increased risk of Graft-versus-Host Disease
(GVHD), which occurs when donor T cells (white blood cells that are involved with the body’s
immune response) attack other tissues or organs like the skin, liver and intestines of the
transplant recipient. In this study, stem cells that are obtained from a partially-matched
donor will be highly purified using the investigational CliniMACS® stem cell selection
device in an effort to achieve specific T cell target values. The primary aim of the study
is to help improve overall survival with haploidentical stem cell transplant in a high risk
patient population by limiting the complication of GVHD.