Allogeneic Stem Cell Transplantationin Relapsed Hematological Malignancy: Early GVHD Prophylaxis

In this study, the investigators will utilize a regimen combining low dose total body
irradiation and rabbit ATG to facilitate stem cell transplantation (SCT) with HLA matched
related and unrelated donors. Based on the hypothesis that early treatment interventions have
significant late effects in allogeneic SCT, a simple intervention, varying the duration of
intense immunosuppression following SCT, will be investigated in this study. This may allow
more robust recovery of donor immune system cells in the first two months following
transplantation and eventually result in lower risk of cancer relapse, while maintaining
effective graft versus host disease (GVHD) control. Patients will be randomly assigned to
receive GVHD prevention therapy using one of two different immunosuppressive regimens with
tacrolimus & mycophenolate mofetil (MMF). Patients assigned to the investigational group will
receive MMF for 15 days following SCT with growth factor support using granulocyte macrophage
colony stimulating factor (GM-CSF) beginning on post-transplant day 4. Patients randomized to
the standard treatment group will receive MMF for 30 days following SCT with cytokine support
using granulocyte colony stimulating factor (G-CSF) beginning on post-transplant day 4. If
one of these treatment groups demonstrates an improvement in donor immune cell recovery,
there may be a slow increase in the likelihood of patients being assigned to that more
successful treatment group. Eventually the two groups will be compared with respect to the
likelihood of either relapse or GVHD developing.

Inclusion Criteria

- Any of the following high risk or recurrent hematological malignancies:

- Hodgkin lymphoma (HL)

- Non-Hodgkin lymphoma (NHL)

- Chronic lymphocytic leukemia (CLL)

- Multiple myeloma (MM)

- Acute myelogenous leukemia (AML)

- Acute lymphocytic leukemia (ALL)

- Chronic myelogenous leukemia (CML)

- Myelodysplastic syndrome (MDS)

*Note: Determination that the malignancy is high risk will be made by the
investigator.

- Investigator determination that the patient is an appropriate candidate for reduced
intensity allogeneic SCT with the standard Massey Cancer Center-Virginia Commonwealth
Health System Bone Marrow Transplant MCC-VCUHS BMT Program regimen employed in this
trial

- Patients with or without previous myeloablative autologous transplant

- HLA-matched stem cell donor, either related (6/6 or 5/6 loci matched) or unrelated
(8/8 or 7/8 loci matched)

*Note: Unrelated donors must be matched at HLA-A, -B, -C, and -DRB1 loci. However, a
single locus mismatch will be acceptable in the event a more closely matched donor is
not available.

- Age ≥ 40 to < 75 years; patients 18 to 39 years of age will be eligible only if the
investigator has determined that the patient has comorbidity(ies) precluding
conventional allogeneic transplantation with full intensity myeloablative conditioning

- Karnofsky Performance Status of 70-100%

- Negative serology for HIV

- Women who are not postmenopausal or have not undergone hysterectomy must have a
documented negative serum pregnancy test per standard MCC-VCUHS BMT Program guidelines

- Ability to understand and the willingness to sign a written informed consent document
*Note: The consent form must be signed and dated prior to initiation of SCT
preparative treatments.

Exclusion Criteria

- Previous therapeutic radiation therapy (RT) that exceeds critical structure tolerance
doses as determined by a radiation oncologist

- Uncontrolled viral, fungal, or bacterial infection

- Active meningeal or central nervous system disease

- Previous therapy with rabbit anti-thymocyte globulin (ATG); previous treatment with
equine ATG is allowed if more than 3 months ago

*Note: Previous myeloablative autologous transplant is permitted but not required.

- Pregnancy or breastfeeding

- Medical, psychological, or social condition that, in the opinion of the investigator,
may increase the patient's risk or limit the patient's adherence with study
requirements