Study of Nonmyeloablative Peripheral Blood Stem Cell Transplant With High-dose Posttransplantation Cyclophosphamide in Hematopoietic Malignancies Including Those That Are Challenging to Engraft

Inclusion Criteria

• •The following are eligibility for study entry and transplantation.
• •Presence of a suitable related, HLA-haploidentical or HLA-matched stem cell donor
• •The donor and recipient must be identical at least one allele of each of the following genetic loci: HLA-A, HLA-B, HLA-Cw, HLA-DRB1, and HLA-DQB1. A minimum match of 5/10 is therefore required for related donors, and will be considered sufficient evidence that the donor and recipient share one HLA haplotype.
• •Eligible diagnoses:
• •Myelodysplastic syndrome (MDS) including chronic myelomonocytic leukemia \[CMML\] with at least one poor risk factor
• •No active extramedullary leukemia or known active CNS involvement by malignancy. Such disease treated into remission is permitted.
• •Any previous autologous HSCT must have occurred at least 3 months prior to start of conditioning
• •No previous allogeneic HSCT
• •Adequate end-organ function Note: Infection is permitted if there is evidence of response to medication. Eligibility of HIV infected patients will be determined on a case-by-case basis.
• •ECOG performance status \< 2 or Karnofsky or Lansky score \> 60.
• •Age \> 18 years and older.
• •Not pregnant or breast-feeding.
• •No uncontrolled infection.
• •Eligible diagnoses:
• •Myelodysplastic syndrome (MDS) including chronic myelomonocytic leukemia \[CMML\] with at least one of the following poor-risk features
• •SLL or CLL with 17p deletion, or with progression \< 6 months after second or greater treatment regimen. Must have the following to be an acceptable candidate as well:
• •* \< 20% of bone marrow cellularity involved by SLL/CLL (to lower risk of graft rejection)
• •* No lymph nodes \> 5 cm in any dimension
• •* No massive splenomegaly, defined as \> 6 cm below the left costal margin
• •T-cell PLL in PR or better prior to transplantation. Must also have \< 20% of bone marrow cellularity involved by PLL (to lower risk of graft rejection).
• •Interferon- or tyrosine kinase-refractory CML in first chronic phase, TKI-intolerant CML in first chronic phase, or CML in second or subsequent chronic phase
• •Philadelphia chromosome negative myeloproliferative disease (including myelofibrosis)
• •o Intermediate-2 or High risk score by DIPSS Plus is required for a diagnosis of myelofibrosis
• •Multiple myeloma or plasma cell leukemia with a PR or better to the last treatment regimen, based on the International Myeloma Working Group (IMWG) criteria.49
• •Hematologic malignancy in complete remission with minimal residual disease (MRD) non detectable OR detectable by conventional cytogenetics, FISH, flow cytometry, or molecular testing or hematologic malignancies in partial remission
• •Donor eligibility
• •Donors must be either:
• •HLA-haploidentical or HLA-identical relatives of the patient based on allele or allele group level typing as defined in Section 4.1.
• •Medically fit to and willing to donate
• •Lack of recipient anti-donor HLA antibody
• •Has not donated blood products to patient