Background:
- High-risk hematologic malignancies generally are incurable without an allogeneic
hematopoietic cell transplant (HCT), but even HCT is associated with high risk of
relapse and very poor overall survival.
- Prophylactic donor lymphocyte infusions (DLI) have been used to prevent relapse in
high-risk diseases; preemptive DLIs have been used for MRD positivity or decreasing
donor chimerism post-transplant; and, therapeutic DLIs have been used to treat overt
morphologic relapse post-transplant.
- Prophylactic, preemptive, and therapeutic DLIs can cause significant
graft-versus-host disease (GVHD), both acute and chronic, based on the dose of
lymphocytes, timing of the infusion, and use of preparative chemotherapy, although
these same factors also may impact on the therapeutic efficacy (graft-versus-tumor
immunity of the DLI).
- Post-transplantation cyclophosphamide (PTCy) reduces rates of severe acute and
chronic graft-versus-host disease (GVHD) and the immunosuppressive burden after HCT.
- In pre-clinical HCT models, very large DLI doses can be given after PTCy, even as
early as 24 hours after PTCy treatment, and significant GVHD is not induced,
different from that seen for DLI infusions in mice treated with T-cell-depleted HCT,
in which fatal GVHD is rapidly induced. This effect in PTCy-treated mice is
dependent on Foxp3+ regulatory T cells.
- In patients treated at the NIH Clinical Center, DLI has been given for clinical
reasons as early as 1 month post-transplant in PTCy-treated patients for infection,
falling chimerism, or relapse and did not cause GVHD in these settings when
additional conditioning was not given and T-cell-depleting antibodies were not used,
both of which may disrupt the regulatory mechanisms induced after PTCy that are
needed to control GVHD.
- The early integration of immunotherapeutic strategies, such as DLIs, after PTCy has
the potential to prevent relapse in patients with high-risk hematologic
malignancies, which may result in improved survival in such patients.
Objectives:
-To determine the maximally tolerated dose of DLI that can be safely administered after
HLA-matched-related HCT and after HLA-haploidentical HCT
Eligibility:
-Recipient Participant:
- Histologically or cytologically confirmed hematologic malignancy classified as high
or very high disease risk by the Refined Disease Risk Index for HCT
- Age 18-65
- At least one potentially suitable human leukocyte antigen (HLA)-matched related or
HLA-haploidentical donor.
- Karnofsky performance score >=60
- Adequate organ function
Design:
- Open-label, single-center, non-randomized, phase I/II study
- All recipient participants will receive myeloablative conditioning,
HLA-matched-related or HLA-haploidentical bone marrow HCT, GVHD prophylaxis
including post- transplantation cyclophosphamide, and prophylactic donor lymphocyte
infusion
- There will be 2 cohorts of recipient participants: one with HLA-matched-related
donors and one with HLA-haploidentical donors
- For HLA-matched HCT, the study will proceed to a small, three-level [1) DLI: 1 x
10^6 CD3+ cells/kg on day +7, 2) DLI: 3 x 10^6 CD3+ cells/kg on day +7, 3) DLI: 1 x
10^7 CD3+ cells/kg on day +7] phase I dose escalation study based on the standard
3+3 approach
- For HLA-haploidentical HCT, the study will proceed to a small, three-level [1) DLI:
1 x 10^5 CD3+ cells/kg on day +7, 2) DLI: 3 x 10^5 CD3+ cells/kg on day +7, 3) DLI:
1 x 10^6 CD3+ cells/kg on day +7] phase I dose escalation study based on the
standard 3+3 approach
- Recipient participants will be evaluated for development of steroid-refractory grade
III- IV acute GVHD (aGVHD) at day +60 as the dose-limiting toxicity.
- Phase II will proceed with DLI at the dose level (separately determined for each HLA
cohort) which is associated with 0-1 of 6 recipient participants with steroid
refractory grade III-IV aGVHD at day +60 and the least amount of toxicity.
- Simon optimal two-stage phase II trial design, to rule out excess steroid refractory
grade III-IV aGVHD with the addition of prophylactic DLI, will be used in the phase
II portion of the study which will enroll an additional 14 evaluable subjects in
each cohort.