HAP2HCT: Partially Matched Family Donor Bone Marrow Transplant in Children and Young Adults with High Risk Cancer

Brief Summary

Allogeneic hematopoietic cell transplant (HCT) is a potential curative therapy for various pediatric hematologic malignancies. However, many eligible pediatric recipients will not have a human leukocyte antigen (HLA)-matched related/sibling donor or a HLA-matched unrelated donor.  Yet, nearly all patients will likely have a readily available haploidentical (partially matched related) donor.

In this study, participants with high-risk hematologic malignancies undergoing HCT who lack an available suitable HLA-matched related/sibling donor or matched unrelated donor will receive a TCRαβ-depleted haploidentical donor HCT with additional memory cell donor leukocyte infusion (DLI). One course of blinatumomab will be empirically added for patients with CD19+ malignancy.

Prior research has shown that elective depletion of CD45RA+ cells provides efficient depletion of B cells and acute GVHD inducing naïve T cells, while preserving hematopoietic progenitor cells and memory T cells. This Phase II protocol builds upon the improved outcomes seen in a previous study by attempting to identify the maximum effective dose of haploidentical donor memory T cells in the early post-transplant setting.

Primary Objectives

• To determine the maximum effective dose for prophylactic CD45RA-depleted DLI when given in the early post-engraftment period
• To assess the efficacy of TCRαβ-depleted progenitor cell graft with additional memory T-cell DLI, plus selected use of blinatumomab, in haploidentical donor hematopoietic cell transplantation for hematologic malignancies

Eligibility Criteria

Inclusion criteria include:

For haploidentical donor:

• At least single haplotype matched (≥ 3 of 6) family member
• At least 18 years old
• Not pregnant or breastfeeding
• HIV negative

For transplant recipient:

• 21 years or younger
• Does not have a suitable HLA-matched sibling donor or volunteer 10/10 HLA-matched unrelated donor available in time for progenitor cell donation
• Has a suitable single haplotype matched (≥ 3 of 6) family member donor
• Diagnosed with high risk hematologic malignancy
• No prior allogeneic HCT
• No autologous HCT within previous 12 months

Study Sites

St. Jude Children’s Research Hospital, Memphis, Tennessee

About this study

This clinical trial will test a type of hematopoietic (blood-making) cell transplant in children and young adults with certain high-risk cancers that are hard to treat. A hematopoietic cell transplant is also known as a bone marrow transplant or stem cell transplant.

This type of transplant replaces damaged or destroyed blood and bone marrow cells with healthy ones from another person. The person who gives you the healthy cells is called a donor.

When patients require a bone marrow transplant, the first type of donor to be considered is a matched sibling (brother or sister) donor.  For patients who have no matched siblings, a matched unrelated volunteer donor is looked at next.  If you have no matched unrelated donor, or if the donor is not available, a partially matched family member donor, such as a parent, sibling, aunt or uncle may be considered.

This study is for patients who do not have a suitable donor match. In this clinical trial, your donor will be a partially matched family member.

Purpose of this clinical trial

The main goal of this study is to learn more about new methods of transplanting blood cells donated by a family member. Researchers will look at how chemotherapy, the transplant cell product and the additional white blood cell infusion affect your body, disease and overall survival.

Eligibility overview

For transplant recipient:

• 21 years or younger
• Does not have a suitable sibling donor or volunteer unrelated donor
• Has a suitable single haplotype matched family member donor
• Diagnosed with high risk hematologic malignancy
• No prior allogeneic stem cell transplant