The proposed trial is a single arm, non-randomized, single center pilot study utilizing CliniMACS CD34 Reagent System for patients following allogeneic hematopoietic stem cell transplant (HSCT) requiring treatment of graft dysfunction or failure.

The primary objective of the study is to estimate the incidence of engraftment with sustained recovery of blood counts, including, absolute neutrophil cell (ANC) and platelet engraftment.

• ANC engraftment is defined as ANC of ≥ 0.5 × 10^9/L for three consecutive laboratory values obtained on different days. Date of ANC recovery is the date of the first of three consecutive laboratory values where the ANC is ≥ 0.5 × 10^9/L.
• Platelet engraftment should reflect no platelet transfusions administered for seven consecutive days. Report the date of the first of three consecutive laboratory values ≥ 20 × 10^9/L obtained on different days.

The secondary objective of the study is to estimate the incidence of Graft-versus-host disease (GvHD) and side effects that can be attributed to the CliniMACS CD34 Selected Cellular Product.

Inclusion Criteria:

• Recipient of allogeneic transplantation, adult ≥18 years, from any type of donor including matched related, matched unrelated, mismatched related or mismatched unrelated or haploidentical donor transplant.

• Documented evidence of graft dysfunction or failure (a-c):

  1. Primary graft Failure: Graft failure is defined as failure to achieve neutrophil engraftment by day +28 or lack of donor chimerism > 50% by day 45 not due to the underlying malignancy;
  2. Poor graft function is defined by at least 2 of the following 3 criteria: Hemoglobin < 8 g/dL, ANC < 0.5x109/L, and platelets < 20x109/L. The cytopenia must be unexplained (such as by disease relapse) and unresponsive to hematopoietic growth factors and must last at least 4 weeks;
  3. Secondary graft failure is defined as poor graft function associated with donor chimerism < 5% after initial engraftment

• Transplanted donor availability

• Negative pregnancy test within seven (7) days of product infusion for women of childbearing potential.

Exclusion Criteria:

• Graft failure due to disease relapse or evidence of disease relapse or progression
• Donor unavailable or unable to collect peripheral HPC by apheresis
• Responsive to conventional measures (such as, hematopoietic growth factor)
• Allergic reaction to murine proteins or iron dextran
• Women of childbearing potential with positive serum HCG

All of the individual participant data collected during the trial, after deidentification, will be shared upon reasonable request provided the investigator whose proposed use of the data has been approved by an independent review committee ("learned intermediary") identified for this purpose executes a data use agreement with NYU Langone Health. Requests may be directed to: Jingmei.hsu@nyulangone.org. The protocol and statistical analysis plan will be made available on Clinicaltrials.gov only as required by federal regulation or as a condition of awards and agreements supporting the research.

No time limit.

Requests should be directed to Jingmei.hsu@nyulangone.org. To gain access, data requestors will need to sign a data access agreement.