Low-dose thymoglobulin for prevention of chronic graft-versus-host disease in transplantation from an HLA-matched sibling donor

Anti-T-lymphocyte globulin improves GvHD-free and relapse-free survival in myelofibrosis after matched related or unrelated donor transplantation

Acute and chronic graft-versus-host disease (GvHD) are major complications of allogeneic hematopoietic cell transplantation (alloHCT). In vivo T-cell depletion with anti-T-lymphocyte globulin (ATLG) as part of the conditioning regimen prior to alloHCT is frequently used as GvHD prophylaxis, but data on its role in myelofibrosis is scarce. We took advantage of an international collaborative network to investigate the impact of ATLG in myelofibrosis undergoing first alloHCT. We included 707 patients (n = 469 ATLG and n = 238 non-ATLG prophylaxis). The cumulative incidence of acute GvHD grade II-IV was 30% for the ATLG group vs. 56% for the non-ATLG group (P < 0.001). Acute GvHD grade III-IV occurred in 20% vs. 25%, respectively (P = 0.01). Incidence of mild-to-severe chronic GvHD was 49% vs. 50% (P = 0.52), while ATLG showed significantly lower rates of severe chronic GvHD (7% vs. 18%; P = 0.04). GvHD-free and relapse-free survival (GRFS) at 6 years was 45% for the ATLG group vs. 37% for the non-ATLG group (P = 0.02), driven by significantly improved GRFS of ATLG in matched related and matched unrelated donors. No significant differences in risk for relapse, non-relapse mortality, and overall survival were observed. Multivariable modeling for GRFS showed a 48% reduced risk of GvHD, relapse, or death when using ATLG.

Improved Long-Term Net Survival after Allogeneic Hematopoietic Cell Transplantation in Patients with Hematologic Malignancies over Two Decades

Allogeneic (allo-) hematopoietic cell transplantation (HCT) has evolved as a curative therapy for hematologic malignancies and diseases, with practice changes over the past 2 decades. This study aimed to evaluate the change in 5-year net survival (NS) of allo-HCT recipients in a population-based cohort over the past 2 decades, which allows the estimation of a more HCT-specific long-term survival rate by considering background mortality changes. This study included 42,064 patients with hematologic malignancies who underwent their first allo-HCT in Japan between 2000 and 2018 and were reported to the Transplant Registry Unified Management Program. We compared the 5-year NS after allo-HCT in 4 consecutive HCT periods (2000 to 2004, 2005 to 2008, 2009 to 2012, and 2013 to 2018). The 5-year NS of the latest period was estimated using the period analysis method. Adjusted excess hazard ratios (EHRs) for 5-year NS over the HCT period were analyzed using an EHR model. In addition to the analysis of all hematologic malignancies, adjusted 5-year NS for each major hematologic malignancy, including acute myelogenous leukemia, acute lymphoblastic leukemia (ALL), myelodysplastic syndrome, adult T cell leukemia/lymphoma, chronic myeloid leukemia (CML), and malignant lymphoma, was analyzed. The probability of adjusted 5-year NS after HCT improved significantly over time: 35% in 2000 to 2004, 39% in 2005 to 2008, 45% in 2009 to 2012, and 49% in 2013 to 2018. The adjusted EHRs were .90 (95% confidence interval [CI], .86 to .93) in the 2005 to 2008 period, .77 (95% CI, .74 to .80) in the 2009 to 2012 period, and .65 (95% CI, .63 to .68) in the 2013 to 2018 period, with the 2000 to 2004 period as the reference. The 5-year NS improved among all hematologic malignancies, with a significant improvement in CML and ALL. The changes in 5-year NS from the 2000 to 2004 period to the 2013 to 2018 period ranged from 46% to 66% in CML and from 41% to 59% in ALL. In addition to the large improvement of 1-year NS, smaller but continued improvement in NS between 1 and 5 years after transplantation was observed. NS at 5 years conditional on being alive at 1 year increased from 64% in 2000 to 2004 to 73% in 2013 to 2018. Even after subtracting the background mortality in the general population, we found a significant improvement in long-term allo-HCT-specific survival rates for patients with hematologic malignancies over the past 2 decades in Japan.

Dynamic changes in physical function during intensive chemotherapy affect transplant outcomes in older adults with AML

Introduction

Intensive chemotherapy (IC) can affect all geriatric assessment (GA) domains in older adults with acute myeloid leukemia (AML), but data on the effects of these changes on transplant outcomes are lacking.

Methods

Therefore, we prospectively assessed the prognostic role of GA domains at diagnosis and allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 51 patients with AML aged ≥60 years who achieved complete remission after IC. We performed both baseline and pre-allo-HSCT GA; moreover, physical function, including a short physical performance battery (SPPB), cognitive function, psychological function, nutritional status, and social support were examined.

Results

All GA domains showed dynamic changes between the two time points. The directions of change were statistically significant for social support, self-reported physical and psychological functions, and distress, but not for nutritional status, cognitive function, or physical function. Among all GA domains at each time point, only poor physical function and its submaneuvers at diagnosis but not at allo-HSCT were significantly associated with inferior survival. In particular, since the direction of change varied between patients, we found that patients whose physical function improved before allo-HSCT were more likely to survive longer than those with persistently impaired SPPB (55.6% vs. 28.6%, p=0.268). Finally, persistent impairment in SPPB (28.6% vs. 65.9%, p=0.006), tandem stand (0% vs. 63.3%, p=0.012), sit-and-stand (41.2% vs. 70.6%, p=0.009), and gait speed (38.5% vs. 68.4%, p=0.027) further strongly predicted inferior survival.

Discussion

This study showed that IC courses can induce dynamic changes in different directions in the GA domains of each patient and that changes in objectively measured physical function can predict transplant outcomes.

[Efficacy analysis of anti-thymocyte globulin regimens with different timing strategies for matched sibling donor hematopoietic stem cell transplantation]

Objective: To compare the effects of two administration time strategies for rabbit antihuman thymocyte immunoglobulin (rATG) of 5mg/kg total dose in matched sibling donor hematopoietic stem cell transplantation (MSD-HSCT) . Methods: This study retrospectively analyzed the clinical data of 32 patients who received MSD-HSCT with 5 mg/kg rATG conditioning regimen at the Department of Hematology of the First Medical Center of the People's Liberation Army General Hospital from October 2020 to April 2022. The patients were classified into two groups: the 4d-rATG group (16 cases), who received antithymocyte globulin (ATG) from day -5 to day -2, and the 2d-rATG group (16 cases), who received ATG from day -5 to day -4. Between the two groups, the transplantation outcomes, serum concentrations of active antithymocyte globulin (ATG) in patients from -4 days to 28 days after graft infusion (+28 days), and the reconstitution of lymphocyte subsets on days +30, +60, and +90 were compared. Results: The cumulative incidences of acute graft-versus-host disease at 100 days after graft infusion were 25.0% (95% CI 7.8% -47.2% ) and 18.8% (95% CI 4.6% -40.2% ) (P=0.605) in the 4d-rATG group and 2d-rATG group, respectively. The 1-year cumulative incidences of chronic graft-versus-host disease were 25.9% (95% CI 8.0% -48.6% ) and 21.8% (95% CI 5.2% -45.7% ) (P=0.896). The 1-year cumulative incidence of relapse was 37.5% (95% CI 18.9% -65.1% ) and 14.6% (95% CI 3.6% -46.0% ) (P=0.135), and the 1-year probabilities of overall survival were 75.0% (95% CI 46.3% -89.8% ) and 100% (P=0.062). The total area under the curve (AUC) of serum active ATG was 36.11 UE/ml·d and 35.89 UE/ml·d in the 4d-rATG and 2d-rATG groups, respectively (P=0.984). The AUC was higher in the 4d-rATG group than that in the 2d-rATG group (20.76 UE/ml·d vs 15.95 UE/ml·d, P=0.047). Three months after graft infusion, the average absolute count of CD8(+) T lymphocytes in the 4d-rATG group was lower than that in the 2d-rATG group (623 cells/μl vs 852 cells/μl, P=0.037) . Conclusion: The efficiencies of GVHD prophylaxis in MSD-PBSCT receiving 4d-ATG regimen and the 2d-rATG regimen were found to be similar. The reconstruction of CD8(+)T lymphocytes in the 2d-rATG group was better than that in the 4d-rATG group, which is related to the lower AUC of active ATG after transplantation.

Polyclonal anti-thymocyte globulins for the prophylaxis of graft-versus-host disease after allogeneic stem cell or bone marrow transplantation in adults

BACKGROUND

Allogeneic haematopoietic stem cell transplantation (SCT) is an established treatment for many malignant and non-malignant haematological disorders. Graft-versus-host disease (GVHD), a condition frequently occurring after an allogeneic SCT, is the result of host tissues being attacked by donor immune cells. It affects more than half of the patients after transplant either as acute and or chronic GVHD. One strategy for the prevention of GVHD is the administration of anti-thymocyte globulins (ATGs), a set of polyclonal antibodies directed against a variety of immune cell epitopes, leading to immunosuppression and immunomodulation.

OBJECTIVES

To assess the effect of ATG used for the prevention of GVHD in patients undergoing allogeneic SCT with regard to overall survival, incidence and severity of acute and chronic GVHD, incidence of relapse, non-relapse mortality, graft failure and adverse events.

SEARCH METHODS

For this update we searched the CENTRAL, MEDLINE, Embase, trial registers and conference proceedings on the 18th November 2022 along with reference checking and contacting study authors to identify additional studies. We did not apply language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) investigating the impact of ATG on GVHD prophylaxis in adults suffering from haematological diseases and undergoing allogeneic SCT. The selection criteria were modified from the previous version of this review. Paediatric studies and studies where patients aged < 18 years constituted more than 20 % of the total number were excluded. Treatment arms had to differ only in the addition of ATG to the standard GVHD prophylaxis regimen.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by the Cochrane Collaboration for data collection, extraction and analyses.

MAIN RESULTS

For this update we included seven new RCTs, leading to a total of ten studies investigating 1413 participants. All patients had a haematological condition which warranted an allogeneic SCT. The risk of bias was estimated as low for seven and unclear for three studies. ATG probably has little or no influence on overall survival (HR (hazard ratio) 0.93 (95 % confidence interval (CI) 0.77 to 1.13, nine studies, n = 1249, moderate-certainty evidence)). Estimated absolute effect: 430 surviving people per 1000 people not receiving ATG compared to 456 people surviving per 1000 people receiving the intervention (95 % CI 385 to 522 per 1000 people). ATG results in a reduction in acute GVHD II to IV with relative risk (RR) 0.68 (95 % CI 0.60 to 0.79, 10 studies, n = 1413, high-certainty evidence). Estimated absolute effect: 418 acute GVHD II to IV per 1000 people not receiving ATG compared to 285 per 1000 people receiving the intervention (95 % CI 251 to 331 per 1000 people). Addition of ATG results in a reduction of overall chronic GvHD with a RR of 0.53 (95 % CI 0.45 to 0.61, eight studies, n = 1273, high-certainty evidence). Estimated absolute effect: 506 chronic GVHD per 1000 people not receiving ATG compared to 268 per 1000 people receiving the intervention (95 % CI 228 to 369 per 1000 people). Further data on severe acute GVHD and extensive chronic GVHD are available in the manuscript. ATG probably slightly increases the incidence of relapse with a RR of 1.21 (95 % CI 0.99 to 1.49, eight studies,  n =1315, moderate-certainty evidence). Non relapse mortality is probably slightly or not affected by ATG with an HR of 0.86 (95 % CI 0.67 to 1.11, nine studies, n=1370, moderate-certainty evidence).   ATG prophylaxis may result in no increase in graft failure with a RR of 1.55 (95 % CI 0.54 to 4.44, eight studies, n = 1240, low-certainty evidence).  Adverse events could not be analysed due to the serious heterogeneity in the reporting between the studies, which limited comparability (moderate-certainty evidence) and are reported in a descriptive manner.   Subgroup analyses on ATG types, doses and donor type are available in the manuscript.

AUTHORS' CONCLUSIONS

This systematic review suggests that the addition of ATG during allogeneic SCT probably has little or no influence on overall survival. ATG results in a reduction in the incidence and severity of acute and chronic GvHD. ATG intervention probably slightly increases the incidence of relapse and probably does not affect the non relapse mortality. Graft failure may not be affected by ATG prophylaxis. Analysis of data on adverse events was reported in a narrative manner. A limitation for the analysis was the imprecision in reporting between the studies thereby reducing the confidence in the certainty of evidence.

Clinical Benefit of Low-Dose Antithymocyte Globulin-Thymoglobulin as Graft-versus-Host Disease Prophylaxis in Patients Receiving Allogeneic Peripheral Blood Stem Cell Transplantation from HLA-Identical Donors

Graft-versus-host disease (GVHD) is a major complication of allogeneic peripheral blood stem cell transplantation (PBSCT). Previous randomized studies have already shown that the use of several types of antihuman T lymphocyte immune globulin (ATG) as GVHD prophylaxis can reduce the incidence of acute GVHD and chronic GVHD. However, the efficacy and safety of PBSCT from HLA-identical donors with low-dose ATG remain unclear. This study aimed to clarify the efficacy and safety of PBSCT from HLA-identical donors with low-dose ATG compared with PBSCT from HLA-identical donors without ATG. To do so, we retrospectively analyzed the outcomes of patients who underwent allogeneic PBSCT from HLA-identical donors with low-dose ATG-thymoglobulin (ATG-T; 2.5 mg/kg) versus those who did not receive ATG-T. Patient data were collected retrospectively from the medical records of Anjo Kosei Hospital. This study was conducted from 2009 to the final follow-up in October 2022. Forty-seven of 91 patients received ATG-T between January 2009 and March 2020. ATG-T reduced the incidence rates of moderate-to-severe chronic GVHD (hazard ratio [HR], .15; 95% confidence interval [CI], .057 to .41; P < .0010) and nonrelapse mortality (HR, .21; 95% CI, .0058 to.75, P = .016) without increasing the risk of relapse. Overall survival did not differ significantly between the 2 groups; however, the low-dose ATG-T group had better moderate-to-severe chronic GVHD-free, relapse-free survival rates (HR, .47; 95% CI, .27 to .80, P = .0054) than the non-ATG-T group. In addition, multistate analysis revealed that the low-dose ATG-T group had better current GVHD-free, relapse-free survival at 24 months after transplantation (45% [95% CI, 29% to 63%)] versus 21% [95% CI, 9.1% to 34%]; P = .015). Low-dose ATG-T was not associated with increased incidence of infections or adverse events. Our findings suggest that low-dose ATG-T can be beneficial for patients receiving PBSCT from HLA-identical donors. © 2023 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Anti-thymocyte globulin could potentially overcome an adverse effect of acute GVHD in matched-related PBSCT

BACKGROUND

Previous Japanese studies have shown that bone marrow transplantation (BMT) is associated with a better survival compared with peripheral blood stem cell transplantation (PBSCT) from matched related donors (MRDs). PBSCT recipients showed a higher incidence of severe graft-versus-host disease (GVHD) and non-relapse mortality (NRM) than BMT recipients. In recent years, the efficacy and safety of anti-thymocyte globulin (ATG) for PBSCT recipients has been reported from around the world.

OBJECTIVE

We aimed to compare BMT and PBSCT to identify current improvements and unmet needs among PBSCT recipients from MRDs. Moreover, we evaluated the impact of ATG administration on the outcomes for PBSCT recipients.

STUDY DESIGN

We retrospectively analyzed patients aged 16 years or older with acute leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who received their first BMT or PBSCT from MRDs between 2009 and 2018 in Japan.

RESULTS

In total, 3599 transplantations were performed (BMT, 1218; PBSCT without ATG [PBSCT-ATG(-)], 2288; and PBSCT with ATG [PBSCT-ATG(+)], 93). The PBSCT-ATG(-) group had a higher NRM rate (hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.08-1.57; p = 0.005) and lower overall survival (OS) rate (HR, 1.16; 95% CI, 1.04-1.30; p = 0.011) than the BMT group. Furthermore, the PBSCT-ATG(-) group had a higher incidence of grade III-IV, stage 2-4 gut, high-risk, and steroid-refractory acute GVHD than the BMT group. Acute GVHDs had a negative impact on NRM and OS rates. PBSCT-ATG(-) was also associated with a higher risk of chronic GVHD (HR: 1.89; 95% CI: 1.24-1.57; p < 0.001) and extensive chronic GVHD (HR: 1.44; 95% CI: 1.23-1.68; p < 0.001). The incidence of acute GVHD, chronic GVHD, and NRM and chronic GVHD-free relapse-free survival rates were comparable between the PBSCT-ATG(+) and BMT groups. The OS rate of patients with acute GVHD in the three donor groups was similar. Patients treated with reduced-intensity conditioning in the PBSCT-ATG(+) group had a higher relapse rate and lower OS rate than those in the BMT group.

CONCLUSIONS

In this Japanese cohort, standard calcineurin inhibitor-based GVHD prophylaxis was not sufficient for PBSCT recipients from MRDs because of the high incidence of severe acute GVHD. Moreover, prophylactic ATG was found to be a promising strategy against GVHD.