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Prophylactic donor lymphocyte infusion after haploidentical hematopoietic cell transplantation and post-transplant cyclophosphamide for treatment of high-risk myeloid neoplasms in children: A retrospective study
Qi, S. S., Chen, Z., Du, Y., Sun, M., Wang, Z., Long, F., Luo, L., Xiong, H.
Pediatric blood & cancer. 2023;:e30659
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Editor's Choice
Abstract
BACKGROUND Post-transplant cyclophosphamide (PTCy) has been recommended for prevention of graft-versus-host disease (GvHD) following haploidentical hematopoietic cell transplantation (haplo-HCT) for treatment of malignant blood diseases, but disease relapse remains a problem. Although donor lymphocyte infusion (DLI) is reported to be effective for treating post-transplantation relapse, the efficacy and safety of prophylactic-DLI (pro-DLI) post haplo-HCT, and PTCy in pediatric patients with hematological malignancies is unknown. METHODS We retrospectively analyzed the outcomes of 54 pediatric patients with high-risk myeloid neoplasms who received a PTCy regimen for GvHD prophylaxis and pro-DLI after haploidentical peripheral blood stem cell transplantation. The high-risk myeloid neoplasms in this cohort included acute myeloid leukemia (n = 46) and myelodysplastic syndromes (n = 8). RESULTS Median follow-up was for 19.7 (range: 3.4-46.6) months. The cumulative incidences of grade II-IV and III-IV acute GvHD were 37.0% (95% CI: 22.7%-48.7%) and 16.7% (95% CI: 6.1%-26.0%), respectively. There were no graft-failure events, and the 2-year rate of moderate/severe chronic GvHD was 8.1% (95% CI: 0%-16.7%). The 2-year non-relapse mortality, relapse, disease-free survival, GvHD-free relapse-free survival, and overall survival rates were 5.1% (95% CI: 0%-11.7%), 16.6% (95% CI: 5.3%-26.6%), 78.9% (95% CI: 68.0%-91.6%), 62.2% (95% CI: 49.4%-78.3%), and 87.3% (95% CI: 78.3%-97.4%), respectively. CONCLUSIONS Prophylactic donor lymphocyte infusion in the setting of haploidentical hematopoietic cell transplantation with post-transplant cyclophosphamide appears to be effective and safe in pediatric patients with high-risk myeloid neoplasms.
PICO Summary
Population
Children with high-risk myeloid neoplasms undergoing haploidentical peripheral blood transplant at a single centre in China (n=54)
Intervention
Post-transplant cyclophosphamide (PTCy) regimen for GvHD prophylaxis and prophylactic donor lymphocyte infusion (pro-DLI)
Comparison
None
Outcome
Median follow-up was for 19.7 (range: 3.4-46.6) months. The cumulative incidences of grade II-IV and III-IV acute GvHD were 37.0% (95% CI: 22.7%-48.7%) and 16.7% (95% CI: 6.1%-26.0%), respectively. There were no graft-failure events, and the 2-year rate of moderate/severe chronic GvHD was 8.1% (95% CI: 0%-16.7%). The 2-year non-relapse mortality, relapse, disease-free survival, GvHD-free relapse-free survival, and overall survival rates were 5.1% (95% CI: 0%-11.7%), 16.6% (95% CI: 5.3%-26.6%), 78.9% (95% CI: 68.0%-91.6%), 62.2% (95% CI: 49.4%-78.3%), and 87.3% (95% CI: 78.3%-97.4%), respectively.
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The infusion of ex vivo, interleukin-15 and -21-activated donor NK cells after haploidentical HCT in high-risk AML and MDS patients-a randomized trial
Lee, K. H., Yoon, S. R., Gong, J. R., Choi, E. J., Kim, H. S., Park, C. J., Yun, S. C., Park, S. Y., Jung, S. J., Kim, H., et al
Leukemia. 2023
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Editor's Choice
Abstract
Clinical effect of donor-derived natural killer cell infusion (DNKI) after HLA-haploidentical hematopoietic cell transplantation (HCT) was evaluated in high-risk myeloid malignancy in phase 2, randomized trial. Seventy-six evaluable patients (aged 21-70 years) were randomized to receive DNKI (N = 40) or not (N = 36) after haploidentical HCT. For the HCT conditioning, busulfan, fludarabine, and anti-thymocyte globulin were administered. DNKI was given twice 13 and 20 days after HCT. Four patients in the DNKI group failed to receive DNKI. In the remaining 36 patients, median DNKI doses were 1.0 × 10(8)/kg and 1.4 × 10(8)/kg on days 13 and 20, respectively. Intention-to-treat analysis showed a lower disease progression for the DNKI group (30-month cumulative incidence, 35% vs 61%, P = 0.040; subdistribution hazard ratio, 0.50). Furthermore, at 3 months after HCT, the DNKI patients showed a 1.8- and 2.6-fold higher median absolute blood count of NK and T cells, respectively. scRNA-sequencing analysis in seven study patients showed that there was a marked increase in memory-like NK cells in DNKI patients which, in turn, expanded the CD8(+) effector-memory T cells. In high-risk myeloid malignancy, DNKI after haploidentical HCT reduced disease progression. This enhanced graft-vs-leukemia effect may be related to the DNKI-induced, post-HCT expansion of NK and T cells. Clinical trial number: NCT02477787.
PICO Summary
Population
Adults 21-70 years undergoing haploidentical transplant for high-risk myeloid malignancy from a single centre in Korea (n=76)
Intervention
Two doses of donor-derived natural killer cell infusion (DNKI) on day 13 and day 20 (n=40)
Comparison
No NK cell infusion (n=36)
Outcome
Intention-to-treat analysis showed a lower disease progression for the DNKI group (30-month cumulative incidence, 35% vs 61%; subdistribution hazard ratio, 0.50). Furthermore, at 3 months after HCT, the DNKI patients showed a 1.8- and 2.6-fold higher median absolute blood count of NK and T cells, respectively. scRNA-sequencing analysis in seven study patients showed that there was a marked increase in memory-like NK cells in DNKI patients which, in turn, expanded the CD8(+) effector-memory T cells.
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Donor lymphocyte infusions after haploidentical stem cell transplantation with PTCY: A study on behalf of the EBMT cellular therapy & immunobiology working party
Santoro, N., Mooyaart, J. E., Devillier, R., Koc, Y., Vydra, J., Castagna, L., Gülbas, Z., Martin, J. D., Araujo, M. C., Kulagin, A., et al
Bone marrow transplantation. 2022
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Editor's Choice
Abstract
Donor lymphocyte infusion (DLI) is a treatment option to prevent or treat relapse after allogeneic hematopoietic cell transplantation (HCT). We here report data for 173 patients who received one or multiple DLIs after haploidentical-HCT with post-transplant cyclophosphamide (PTCY) at 47 EBMT centers from 2009 to 2018. Indication for DLI was: prophylactic for 59(34.3%), preemptive for 20(11.6%), and therapeutic for 93(54.1%). For the prophylactic group, the median number of DLIs was 1 (IQR:1-2.5) with a median first dose of 0.1 × 10(6) CD3+ T cell/kg, for the preemptive 2 (IQR:1-3) with 0.5 × 10(6) CD3+ T cell/kg, for the therapeutic 1 (IQR:1-3) with 1 × 10(6)CD3+ Tcell/kg, respectively. OS after first DLI was 61% (46-75%) for prophylactic, 40% (19-61%) for preemptive, and 22% (13-31%) for therapeutic. CI of II-IV aGVHD and cGVHD was 17%(7-27%) and 53% (40-67%) for the prophylactic, 20% (2-38%) and 21% (3-39%) for the preemptive, 17% (9-24%) and 24% (15-33%) for the therapeutic group, respectively. Our data show great variability in the indications and modalities of DLI across responding EBMT centers. Survival rates remain relatively low in patients with active disease. While the cumulative incidence of aGVHD appears acceptable, we showed a high incidence proportion of cGVHD in the prophylactic group, compared with preemptive and therapeutic DLI. These data should be investigated further in prospective clinical trials.
PICO Summary
Population
Adults drawn from 47 EBMT centres receiving donor lymphocyte infusions (DLIs) after haploidentical transplant with post-transplant cyclophosphamide (n=173)
Intervention
DLIs for a prophylactic indication (n=59)
Comparison
DLIs for a pre-emptive indication (n=20), or a therapeutic indication (n=93)
Outcome
For the prophylactic group, the median number of DLIs was 1 (IQR:1-2.5) with a median first dose of 0.1 × 10(6) CD3+ T cell/kg, for the pre-emptive 2 (IQR:1-3) with 0.5 × 10(6) CD3+ T cell/kg, for the therapeutic 1 (IQR:1-3) with 1 × 10(6)CD3+ Tcell/kg, respectively. Overall survival after first DLI was 61% (46-75%) for prophylactic, 40% (19-61%) for pre-emptive, and 22% (13-31%) for therapeutic. Cumulative incidence of II-IV acute GVHD and chronic GVHD was 17%(7-27%) and 53% (40-67%) for the prophylactic, 20% (2-38%) and 21% (3-39%) for the pre-emptive, 17% (9-24%) and 24% (15-33%) for the therapeutic group, respectively.
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Donor lymphocyte infusion after haploidentical hematopoietic stem cell transplantation for acute myeloid leukemia
Harada, K., Mizuno, S., Yano, S., Takami, A., Ishii, H., Ikegame, K., Najima, Y., Kako, S., Ashida, T., Shiratori, S., et al
Annals of hematology. 2022
Abstract
Although haploidentical donor lymphocyte infusion (DLI) is a valid treatment option for relapsed acute myeloid leukemia (AML), the incidence and risk factors for graft-versus-host disease (GVHD) and the efficacy of haploidentical DLI have not been fully evaluated. We retrospectively analyzed the outcomes after haploidentical DLI for 84 patients with AML using a nationwide database and additional questionnaires. The median number of DLI cycles and infused CD3(+) cell dose was 1 and 1.0 × 10(6)/kg, respectively. The infused CD3(+) cell count of 5.0 × 10(5)/kg or higher was associated with acute GVHD (grade II-IV, 32.1% vs. 10.5%, p = 0.03; grade III-IV, 21.4% vs. 5.3%, p = 0.10). Patients who developed grade III-IV acute GVHD more frequently succumbed to treatment-related mortality (46.7% vs. 15.8% at 1 year, p = 0.002), although the relapse-related mortality was significantly low (40.0% vs. 72.2% at 1 year, p = 0.025). The overall response to DLI was significantly higher in the preemptive DLI group (47.4%) than in the therapeutic group (13.9%, p = 0.002). In the multivariate analysis, preemptive DLI was the predictive factor for overall response (odds ratio, 5.58; p = 0.003). Our results indicated the substantial risk of acute GVHD after haploidentical DLI with CD3(+) cell count of 5.0×10(5)/kg or higher and the favorable outcomes after preemptive DLI.
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Haploidentical transplantation has a superior graft-versus-leukemia effect than HLA-matched sibling transplantation for Ph- high-risk B-cell acute lymphoblastic leukemia
Fan, M., Wang, Y., Lin, R., Lin, T., Huang, F., Fan, Z., Xu, Y., Yang, T., Xu, N., Shi, P., et al
Chinese medical journal. 2021
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Abstract
BACKGROUND Compared with human leukocyte antigen (HLA)-matched sibling donor (MSD) transplantation, it remains unclear whether haploidentical donor (HID) transplantation has a superior graft-versus-leukemia (GVL) effect for Philadelphia-negative (Ph-) high-risk B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to compare the GVL effect between HID and MSD transplantation for Ph- high-risk B-ALL. METHODS This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Immunosuppressant withdrawal and prophylactic or pre-emptive donor lymphocyte infusion (DLI) were administered in patients without active graft-versus-host disease (GVHD) to prevent relapse. All patients with measurable residual disease (MRD) positivity post-transplantation (post-MRD+) or non-remission (NR) pre-transplantation received prophylactic/pre-emptive interventions. The primary endpoint was the incidence of post-MRD+. RESULTS A total of 335 patients with Ph- high-risk B-ALL were enrolled, including 145 and 190, respectively, in the HID and MSD groups. The 3-year cumulative incidence of post-MRD+ was 27.2% (95% confidence interval [CI]: 20.2%-34.7%) and 42.6% (35.5%-49.6%) in the HID and MSD groups (P = 0.003), respectively. A total of 156 patients received DLI, including 60 (41.4%) and 96 (50.5%), respectively, in the HID and MSD groups (P = 0.096). The 3-year cumulative incidence of relapse was 18.6% (95% CI: 12.7%-25.4%) and 25.9% (19.9%-32.3%; P = 0.116) in the two groups, respectively. The 3-year overall survival (OS) was 67.4% (95% CI: 59.1%-74.4%) and 61.6% (54.2%-68.1%; P = 0.382), leukemia-free survival (LFS) was 63.4% (95% CI: 55.0%-70.7%) and 58.2% (50.8%-64.9%; P = 0.429), and GVHD-free/relapse-free survival (GRFS) was 51.7% (95% CI: 43.3%-59.5%) and 37.8% (30.9%-44.6%; P = 0.041), respectively, in the HID and MSD groups. CONCLUSION HID transplantation has a lower incidence of post-MRD+ than MSD transplantation, suggesting that HID transplantation might have a superior GVL effect than MSD transplantation for Ph- high-risk B-ALL patients. TRIAL REGISTRATION ClinicalTrials.gov: NCT01883180, NCT02673008.
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Safety and efficacy of the low-dose memory (CD45RA-depleted) donor lymphocyte infusion in recipients of aß T cell-depleted haploidentical grafts: results of a prospective randomized trial in high-risk childhood leukemia
Dunaikina, M., Zhekhovtsova, Z., Shelikhova, L., Glushkova, S., Nikolaev, R., Blagov, S., Khismatullina, R., Balashov, D., Kurnikova, E., Pershin, D., et al
Bone marrow transplantation. 2021
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Editor's Choice
Abstract
Depletion of aß T cells from the graft prevents graft-vs.-host disease (GVHD) and improves outcome of HSCT from haploidentical donors. In a randomized trial, we aimed to evaluate the safety and efficacy of low-dose memory (CD45RA-depleted) donor lymphocytes (mDLI) after HSCT with aß T-cell depletion. A cohort of 149 children was enrolled, 76 were randomized to receive scheduled mDLI and 73 received standard care. Conditioning was based on either 12?Gy total body irradiation or treosulfan. Rabbit antithymocyte globulin was replaced by tocilizumab and abatacept. Primary end points were the incidence of acute GVHD grades II-IV and the incidence of cytomegalovirus (CMV) viremia. The incidence of grades II-IV aGVHD was 14% in the experimental arm and 12% in the control arm, p-0.8. The incidence of CMV viremia was 45% in the experimental arm and 55% in the control arm, p-0.4. Overall, in the total cohort 2-year NRM was 2%, cumulative incidence of relapse was 25%, event-free survival 71%, and overall survival 80%, without difference between the study arms. Memory DLI was associated with improved recovery of CMV-specific T-cell responses in a subcohort of CMV IgG seropositive recipients.
PICO Summary
Population
Children with high-risk leukaemia undergoing of aß T cell-depleted haploidentical transplantation (n=149)
Intervention
Scheduled mDLI: low-dose memory (CD45RA-depleted) donor lymphocytes (Experimental arm, n=76)
Comparison
Standard care (Control arm, n=73)
Outcome
The incidence of grades II-IV aGVHD was 14% in the experimental arm and 12% in the control arm. The incidence of CMV viremia was 45% in the experimental arm and 55% in the control arm. Overall, in the total cohort 2-year NRM was 2%, cumulative incidence of relapse was 25%, event-free survival 71%, and overall survival 80%, without difference between the study arms. Memory DLI was associated with improved recovery of CMV-specific T-cell responses in a subcohort of CMV IgG seropositive recipients.
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CTLA4Ig-primed donor lymphocyte infusions following haploidentical transplantation improve outcome with a distinct pattern of early immune reconstitution as compared to conventional donor lymphocyte infusions in advanced hematological malignancies
Jaiswal, S. R., Bhakuni, P., Bhagawati, G., Aiyer, H. M., Soni, M., Sharma, N., Jaiswal, R. R., Chakrabarti, A., Chakrabarti, S.
Bone marrow transplantation. 2021;56(1):185-194
Abstract
CTLA4Ig has a unique property to spare or even potentiate natural killer (NK) cell-mediated cytotoxicity, whilst inhibiting T cell activation. We explored the efficacy of prophylactic DLI following CTLA4Ig (CTLA4Ig-DLI group, n = 75), compared to conventional DLI (DLI group, n = 50), in patients with advanced hematological malignancies receiving PTCy-based haploidentical transplantation. Acute and chronic GVHD in the CTLA4Ig-DLI group were 9.6% and 15.3% compared to 18.8% [p = 0.09] and 36.5% [p = 0.01] in the DLI group. Both non-relapse mortality (4% vs 14.4%) and disease progression (DP) (15.7% vs 31.1%) were lower in CTLA4Ig-DLI group (p = 0.04). GVHD and progression-free survival was significantly improved in the CTLA4Ig-DLI group (p = 0.001). The recovery of CD56(dim)NK cells, NKG2A-KIR + NK subsets and Tregs was significantly better in the CTLA4Ig-DLI group at all time points and memory T cells at day +90. Immune recovery in relation to DP showed distinct patterns, with T cell subsets in the DLI group and NKG2A(-)KIR(+)NK cells in CTLA4Ig-DLI group having favorable impact. CTLA4Ig-DLI was thus associated with an improved outcome, possibly on account of the distinct pattern of immune recovery shown with this novel approach.
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Early and Sustained Expansion of Adaptive Natural Killer Cells Following Haploidentical Transplantation and CTLA4Ig-Primed Donor Lymphocyte Infusions Dissociate Graft-versus-Leukemia and Graft-versus-Host Effects
Jaiswal, S. R., Chakraborty, S., Lakhchaura, R., Shashi, P., Mehta, A., Soni, M., Chakrabarti, S.
Transplantation and cellular therapy. 2021;27(2):144-151
Abstract
BACKGROUND Adaptive or memory natural killer (NK) cells with epigenetic imprints similar to memory T cells have been shown to develop in response to cytomegalovirus (CMV) infection with upregulation of activating receptor NKG2C. These cells have been shown to possess strong anti-tumour efficacy both in-vitro as well as in-vivo. OBJECTIVES To determine if reconstitution of adaptive NK cells (CD56(dim)NKG2C(+)NKG2A(-)) in patients with advanced leukemia undergoing haploidentical HCT had any impact on disease progression (DP). STUDY DESIGN The study cohort comprised of 60 patients with advanced acute leukemia, aged 2-65 years, receiving myeloablative PTCy based haploidentical transplantation from CMV seropositive donors, followed by CTLA4Ig-primed donor lymphocyte infusions (DLI). They were evaluated for the kinetics of reconstitution of adaptive NK cells, both phenotypic and functional, at days +30,+60, +90 and at regular intervals, to 3 years of follow-up, in relation to DP. Reconstitution of adaptive NK cells was compared with a retrospective cohort of patients in the same protocol receiving DLI without CTLA4Ig. RESULTS Non-relapse mortality, acute and chronic GVHD were 5.1%, 10.3% and 14.5%. DP was 17.5% at a median follow-up of 28 months. Adaptive NK cells were significantly higher in patients without DP at days+30, +60 and +90 (p = 0.0001), irrespective of CMV reactivation and remained elevated until 36 months post-HCT. These cells maintained their functional competence as measured by robust interferon-gamma production with higher expressions of KIR, NKG2D and CD57, without any increase in PD1 expression. Grafts from donors with higher adaptive NK cells were associated with a lower risk of DP (p = 0.0001). In multivariate analysis, adaptive NK cell recovery at day +90 had the most favorable impact on DP (HR-0.7). Tregs reconstituted briskly along with the adaptive NK cells and were sustained as well, without compromising the GVL effect. Comparison with a retrospective cohort receiving the same protocol with DLI without CTLA4Ig, showed a superior reconstitution of adaptive NK cells in those receiving CTLA4Ig-DLI (p < 0.0001). CONCLUSION Our study suggests that myeloablative transplantation from CMV seropositive haploidentical donors augmented with CTLA4Ig-primed DLI might favor early and sustained expansion of functionally competent adaptive NK cells irrespective of CMV reactivation, with a favorable outcome.
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Feasibility and Efficacy of CD45RA+ Depleted Donor Lymphocytes Infusion After Haploidentical Transplantation With Post-Transplantation Cyclophosphamide in Patients With Hematological Malignancies
Castagna, L., Valli, V., Timofeeva, I., Capizzuto, R., Bramanti, S., Mariotti, J., De Philippis, C., Sarina, B., Mannina, D., Giordano, L., et al
Transplantation and cellular therapy. 2021
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Editor's Choice
Abstract
Allogeneic stem cell transplantation from haploidentical donor using post-transplantation cyclophosphamide has been used to cure hematological diseases. Because of slow immunological reconstitution, there is an increased incidence of viral infection. The aim of our study was to prospectively evaluate the efficacy and the feasibility of a CD45RA+ depleted donor lymphocytes infusion (DLI) in terms of reduction of viral infection early after haploidentical transplantation. This a prospective single-center study. We enrolled 23 patients, of whom 19 were evaluable. Graft-versus-host disease (GVHD) prophylaxis was the same for all patients. The primary endpoint was 100-day cumulative incidence of viral infections. The primary endpoint was met, because the 100-day cumulative incidence of viral infection was 32%. The median time from transplantation to first CD45RA+ depleted DLI was 55 days (range, 46-63). 28% of patients had cytomegalovirus reactivation, no patients reactivated human herpesvirus-6; 1 patient developed BK virus related hemorrhagic cystitis. Most of the patients received the planned 3 infusions. Only 1 patient had development of grade 2 acute GVHD, and 2 patients had moderate chronic GVHD. All evaluable patients were off immunosuppressive therapy at last follow-up. The median follow-up was 12 months (range, 3-23), the 1-year overall survival and progression-free survival were 79% and 75%, respectively; the 100-day and 1-year NRM were 5% and 12%, respectively. CD45RA+ depleted DLI are feasible in patients treated with haploidentical transplantation. The toxic profile is good with a low risk for development of both acute and chronic GVHD.
PICO Summary
Population
Patients with haematological malignancies (n=23)
Intervention
Haploidentical stem cell transplantation with CD45RA+ depleted donor lymphocytes infusion (DLI)
Comparison
None
Outcome
The 100-day cumulative incidence of viral infection was 32%. The median time from transplantation to first CD45RA+ depleted DLI was 55 days (range, 46-63). 28% of patients had cytomegalovirus reactivation, no patients reactivated human herpesvirus-6; 1 patient developed BK virus related hemorrhagic cystitis. Most of the patients received the planned 3 infusions. Only 1 patient had development of grade 2 acute GVHD, and 2 patients had moderate chronic GVHD. All evaluable patients were off immunosuppressive therapy at last follow-up. The median follow-up was 12 months (range, 3-23), the 1-year overall survival and progression-free survival were 79% and 75%, respectively; the 100-day and 1-year NRM were 5% and 12%, respectively.
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Serotherapy-Free Regimen Improves Non-Relapse Mortality and Immune Recovery Among the Recipients of aß TCell-Depleted Haploidentical Grafts: Retrospective Study in Childhood Leukemia
Shelikhova, L., Glushkova, S., Nikolaev, R., Dunaikina, M., Zhekhovtsova, Z., Blagov, S., Khismatullina, R., Balashov, D., Kurnikova, E., Pershin, D., et al
Transplantation and cellular therapy. 2021;27(4):330.e1-330.e9
Abstract
Depletion of aß T cells from the graft prevents graft-versus-host disease (GVHD) and improves the outcome of hematopoietic stem cell transplantation (HSCT) from haploidentical donors. Delayed recovery of adaptive immunity remains a problem, which can be approached by adoptive T-cell transfer. In a randomized trial, we have assessed the safety and efficacy of low-dose memory (CD45RA-depleted) donor lymphocytes (mDLI) after HSCT with aß T-cell depletion. Antithymocyte globulin (ATG) is viewed as an essential component of preparative regimen, critical for both prevention of graft failure and GVHD. Variable pharmacokinetics of ATG may significantly affect lymphocyte subpopulations after HSCT. To uncover the potential of mDLI, we replaced rabbit ATG with tocilizumab and abatacept. Here we compare post hoc the immune recovery and the key clinical outcomes, including nonrelapse mortality (NRM), overall- and event-free survival (OS and EFS), between the cohort enrolled in the prospective randomized trial and a historical cohort, comprised of patients grafted with a conventional ATG-based HSCT with aß T cell depletion. A cohort of 149 children was enrolled in the prospective trial and 108 patients were selected as historical controls from a prospectively populated database. Patient population was comprised of children with high-risk hematologic malignancies, with more than 90% represented by acute leukemia. Median age at enrollment was 8.8 years. In the prospective cohort 91% of the donors were haploidentical parents, whereas in the historical cohort 72% of the donors were haploidentical. Conditioning was based on either 12Gy total body irradiation or treosulfan. Thiotepa, fludarabine, bortezomib, and rituximab were used as additional agents. Patients in the historical cohort received rabbit ATG at 5 mg/kg total dose, while prospective cohort patients received tocilizumab at 8 mg /kg on day -1 and abatacept at 10 mg/kg on days 0, 7, 14, and 28. Patients in the prospective trial cohort were randomized 1:1 to receive mDLI starting on day 0, whereas 69% of historical cohort patients received mDLI after engraftment, as part of previous trials. Primary engraftment rate was 99% in the prospective cohort and 98% in the historical cohort. The incidence of grade II-IV aGVHD was 13% in the prospective cohort and 16 % in the control group. Chronic GVHD developed among 13% (historical) and 7% (prospective) cohorts (P = .07). The incidence of cytomegalovirus viremia was 51% in the prospective cohort arm and 54% in the historical control arm (p = ns). Overall, in the prospective cohort 2-year NRM was 2%, incidence of relapse was 25%, EFS was 71%, and OS was 80%, whereas in the historical cohort 2-year NRM was 13%, incidence of relapse was 19%, EFS was 67%, and OS was 76%, difference non-significant for relapse and survival. NRM was significantly improved in the ATG-free cohort (P = .002). Recovery of both aß- and ?d- T cells was significantly improved at days +30 and +60 after HSCT in recipients of ATG-free preparative regimens, as well as recovery of naïve T cells. Among the recipients of aß T-cell-depleted grafts, replacement of ATG with nonlymphodepleting abatacept and tocilizumab immunomodulation did not compromise engraftment and GVHD control and was associated with significantly lower NRM and better immune recovery early after HSCT.