Cases Of Primary Graft Failure Research Articles

Outcomes with allogeneic stem cell transplant using cryopreserved versus fresh hematopoietic progenitor cell products

BackgroundAllogeneic hematopoietic stem cell transplant (alloHSCT) is a mainstay of treatment for hematologic malignancies such as acute leukemias and aggressive lymphomas. Historically, fresh hematopoietic progenitor cell (HPC) products have been preferred to cryopreserved products (cryo-HPC) due to concerns of loss of stem cell viability and number with the cryopreservation procedure. ObjectiveWe aimed to analyze the outcomes of patients who received cryo-HPCs during the COVID-19 pandemic and compare this against historical cohorts that received fresh HPC. Study DesignA retrospective chart review was conducted on all adult patients who received a peripheral blood alloHSCT in British Columbia, Canada between June 2017 and November 2021. Baseline characteristics, Kaplan-Meier (KM) overall survival (OS), engraftment, and incidences of acute and chronic graft versus host disease were compared between patients who received cryo-HPCs and fresh HPCs. Univariable analysis followed by multivariable analysis was performed using a backward stepwise selection procedure to generate predictors of OS, cumulative incidence of relapse (CIR), nonrelapse mortality (NRM), and primary and secondary graft failure. ResultsThree hundred eighty-three patients were included in the analysis, with cryo-HPC representing 40%. Median viability was higher in the fresh-HPC group at 99.2% (IQR 98.3–99.5) versus cryo-HPCs at 97.0% (96.0, 98.6) (P < 0.01). The 12-month actuarial survivals were 77% in the fresh HPC and 75% in the cryo-HPC groups (P = 0.21). There were no differences between cryo-HPCs and fresh HPCs on univariable analysis of OS, CIR, or NRM. There was a shorter median time to platelet engraftment in patients receiving fresh HPC at 17 days (IQR 16, 20) versus cryo-HPC at 21 days (IQR 18, 29), P < 0.001. There was a shorter median time to neutrophil engraftment in the fresh HPC group at 17 days (IQR 14, 20) versus 20 days (17, 23), P < 0.001. Cryo-HPC accounted for 5 out of 6 cases of primary graft failure (P = 0.04), and 3 out of five cases of secondary graft failure (P = 0.39). There were no significant differences in acute GVHD between the fresh HPC and cryo-HPC groups (P = 0.34). The incidence of moderate or severe chronic GVHD was 32% in the fresh-HPC group and 17% in the cryo-HPC group (P < 0.001).In multivariable analysis, cryopreservation did not emerge as an independent predictor of OS, CIR, NRM, primary GF or secondary GF. However, viability <90% on arrival at our center was a significant predictor of OS (HR 5.3, 2.3–12.3, P < 0.01), primary graft failure (OR 36.3, 5.4–210.2, P < 0.01), and secondary graft failure (OR 18.4, 1.7–121.1, P < 0.01). ConclusionsPatients who received cryo-HPCs had similar OS and relapse rates to those who received fresh-HPCs but typically took 2–3 days longer to achieve engraftment of platelets or neutrophils and were associated increased primary graft failure. However, after accounting for multiple variables, cryopreservation was no longer a significant predictor of survival or engraftment while viability <90% emerged as an important predictor of OS, primary graft failure, and secondary graft failure. If confirmed, this suggests that viability on arrival at the infusion center may be a good quality control indicator used to identify HPC products that may warrant recollection if the risk of graft failure is sufficiently increased.

Comparison of hematopoietic stem cell transplantation and repeated intensified immunosuppressive therapy as second-line treatment for relapsed/refractory severe aplastic anemia.

The optimal treatment for patients with severe aplastic anemia (SAA) who fail an initial course of antithymocyte globulin (ATG) plus cyclosporine has not yet been established. We compared the effectiveness of allogeneic hematopoietic stem cell transplantation (allo-HSCT) (n = 36) with repeated immunosuppressive therapy (IST) (n = 33) for relapsed/refractory SAA between 2007 and 2022. In the IST group, patients were retreated with ATG (n = 16) or high-dose cyclophosphamide (n = 17). The overall response rate was 57.6% at 6 months and 60.6% at 12 months. In the allo-HSCT group, patients received a transplant from a matched sibling donor (n = 6), matched unrelated donor (n = 7), or haploidentical donor (n = 23). All patients achieved neutrophil engraftment, and there were no cases of primary graft failure. The cumulative incidences (CIs) of grades II-IV and III-IV acute graft-versus-host disease (GVHD) were 36.1% ± 0.7% and 13.9% ± 0.3% at day +100, respectively. The 4-year CI of chronic GVHD (cGVHD) was 36.2% ± 0.7%, with moderate to severe cGVHD at 14.9% ± 0.4%. Compared with IST, HSCT recipients showed much higher hematologic recovery rate at 3, 6, and 12 months (63.9%, 83.3%, and 86.1%, respectively, p < 0.001). The estimated 4-year overall survival (OS) (79.8% ± 6.8% vs. 80.0% ± 7.3%, p = 0.957) was similar; however, the failure-free survival (FFS) was significantly better in the HSCT group (79.8% ± 6.8% vs. 56.6% ± 8.8%, p = 0.049). Of note, children in the HSCT cohort were all alive without treatment failures, exhibiting superior OS (100% vs. 50.0% ± 17.7%, p = 0.004) and FFS (100% vs. 50.0% ± 17.7%, p = 0.004) than children in the IST cohort. Subgroup analysis revealed that younger patients (age ≤ 35 years), especially children, and those with refractory SAA benefited more from HSCT. Therefore, for these patients, salvage HSCT may be more preferable than a second course of IST.

Itacitinib for Prevention of Graft-Versus-Host Disease and Cytokine Release Syndrome with T-Cell Replete Peripheral Blood Haploidentical Transplantation

Introduction: Haploidentical peripheral blood allogeneic hematopoietic cell transplantation (PB haplo-HCT) can be complicated by graft-versus-host disease (GVHD) and cytokine release syndrome (CRS). Acute GVHD rates are higher with PB grafts compared with bone marrow, affecting 35-45% of patients and outcomes are poor in steroid refractory cases. Severe CRS occurs in 10-15% of patients receiving PB haplo-HCT and is associated with high non-relapse mortality and one-year overall survival between 25-30%. As interferon-γ and IL-6 are important mediators in both acute GVHD and CRS, we hypothesized that JAK1 inhibition with itacitinib could prevent these toxicities without impairing engraftment. Here we report outcomes from our study of itacitinib with haplo-HCT (NCT03755414). Methods: Patients with AML, MDS, ALL, or NHL in remission undergoing PB haplo-HCT were treated with itacitinib 200 mg/day on days -3 through +100 (first 20 patients) or 180 (second 22 patients), followed by a taper. Myeloablative and reduced intensity conditioning were allowed. GVHD prophylaxis was tacrolimus, mycophenolate mofetil, and post-transplant cyclophosphamide. Primary outcomes were incidence of primary graft failure and incidence of grade III-IV acute GVHD. Secondary outcomes included incidence and severity of CRS, relapse, GRFS, and overall survival. Results: Forty-two patients were enrolled and underwent transplantation on study between November 2019 and December 2022, median days of follow up was 453 days (range 142-1259). The patient population had a median age of 60 years (20 - 73 years) with the majority of patients having AML (AML 60%, ALL 21%), MDS 10%, MF 5%, NHL 4%). All patients with AML, MDS, or ALL were in a complete morphologic remission, although 45% had disease by either cytogenetics, next generation sequencing, or measurable residual disease assay (flow cytometry for AML/MDS, NGS for ALL). There were no cases of grade III-IV acute GVHD. The cumulative incidence of grade II acute GVHD on day 100 was 17.3% (95% CI, 7% - 31%), day 180 was 20.5% and day 365 was 20.5%. There were no cases of severe CRS with 90% of patients having grade 1 CRS and 10% having no CRS. No anti-IL6R or steroid therapy was used. There were no cases of primary graft failure. The cumulative incidence of relapse at 1 year was 10% (95% CI, 3% to 22%) and at 2 years was 14% (95% CI, 5% to 29%). In patients who survived without relapse to day 100, the 1-year cumulative incidence of moderate or severe chronic GVHD was 5% (95% CI 1% - 17%). The refined GRFS at day +180 was 85% (95% CI 69% - 93%) and at day +365 was 79% (95% CI 62% - 89%). Overall survival at 180 days 87% (95% CI 72% - 94%) and at 1 year was 80% (95% CI 63% - 90%). Analysis of peripheral blood mononuclear cells at day +28, +60, and +100, revealed that patients on itacitinib, compared with control haplo-HCT patients, had lower numbers of CD4 and CD8 central memory T cells, lower numbers of CD4 and CD8 naïve T cells, and higher numbers of classical monocytes, nonclassical monocytes, and both myeloid and plasmacytoid dendritic cells. In itacitinib treated patients, T-cell subsets expressed lower LAG3 and PD-1 and higher TIGIT, while monocytes expressed higher HLA-DR, CD80, and CD86. Conclusions: Itacitinib with PB haplo-HCT was safe with low rates of acute and chronic GVHD, without increased risk of relapse or transplant related mortality. Severe CRS was not seen in this trial, and no anti-IL6 or steroid therapy was used. The addition of Jak inhibition to standard PtCy based GVHD prophylaxis was associated with encouraging rates of GRFS and OS on this pilot and expansion study. Patients on itacitinib have unique immune reconstitution characteristics both in terms of PBMC counts and signaling markers within subsets.

Splenic Irradiation Prior to Allogeneic Hematopoietic Cell Transplantation for Patients with Myelofibrosis

Background: Myelofibrosis (MF) is a clonal stem cell neoplasm characterized by excess fibrous tissue formation in the bone marrow. Allogeneic hematopoietic cell transplantation (HCT) is the only curative treatment for MF. Patients with MF often have compensatory splenic extramedullary hematopoiesis leading to splenomegaly, which is associated with delayed engraftment and decreased survival post-HCT. Several Janus kinase (JAK) inhibitors are approved to treat splenomegaly and systemic symptoms in MF patients. However, JAK inhibitor therapy does not always lead to complete resolution of splenomegaly. Therefore, splenic irradiation (RT) prior to HCT may benefit patients with persistent splenomegaly, yet research investigating outcomes of this therapeutic approach is limited. Methods: We conducted a single-center, retrospective cohort study of MF patients to characterize the feasibility of splenic RT and assess engraftment rates and post-transplant outcomes with this approach. Forty-eight MF patients who underwent HCT at Massachusetts General Hospital between 2011 to 2021 were identified using an institutional transplant database. Patient disease- and transplant-related characteristics were summarized according to splenic RT within 3 months prior to transplant. Results: Baseline disease- and transplant-related characteristics are displayed in Table 1. Among all patients, twenty-nine (60%) were male, and the median age was 67 years (range, 53-77). All patients received reduced intensity conditioning, with a majority (81%) receiving fludarabine with melphalan. Seventy-three percent of patients had a JAK2 mutation and 46% received ruxolitinib (RUX) prior to HCT. A total of 17 (35%) patients received splenic RT prior to transplant. Splenic RT ranged from 2 daily doses of 1 Gy to 5 daily doses of 1.5 Gy, with total radiation ranging from 2 Gy to 7.5 Gy. Splenic RT was administered at a median of 13 days prior to transplant (range, 7-69 days). All splenic RT patients had splenomegaly prior to transplant, and 11 (65%) were treated with RUX prior to HCT. Patients receiving splenic RT had significantly larger spleen sizes prior to transplant (23.1 v. 17.3 cm, p<0.01), and were more likely to have at least one high molecular risk (HMR) mutation than patients in the no RT group (83% v. 33%, p=0.01). For the entire cohort, the median days to neutrophil engraftment and platelet engraftment was 14 and 23, respectively. Among splenic RT patients, there was one case of primary graft failure and one case of secondary graft failure. The median days to neutrophil engraftment was 15 (IQR, 13-19) for the RT group and 13 (IQR, 12-14) for the no RT group (p=0.07). The median days to platelet engraftment was 32 (IQR, 25-108) for the RT group and 22 (IQR, 18-25) for the no RT group (p<0.01). Three splenic RT patients (18%) died early without platelet engraftment. When RUX was accounted, patients with RT and RUX had a substantially delayed platelet engraftment compared to no RT and/or no RUX (69.5 days vs 19.5-22.5 days, p=0.03) [Figure 1]. For the entire cohort, the 3-year overall survival (OS) and progression-free survival (PFS) was 67% (95%CI: 50%-79%) and 61% (95%CI: 45%-74%), respectively. The cumulative incidence of non-relapse mortality (NRM) and relapse was 26% (95%CI: 13%-40%) and 13% (95%CI: 5%-24%), respectively. Despite delayed platelet engraftment, survival outcomes were not different between RT and no RT, regardless of pre-HCT RUX exposure. Conclusion: Splenic RT administration prior to HCT appears feasible and associated with acceptable engraftment and clinical outcomes for MF patients with splenomegaly at the time of transplant. The persistence of massive splenomegaly at transplant following pre-transplant RUX is likely indicative of higher risk disease and remains associated with longer time to platelet engraftment, despite the addition of splenic RT. Larger prospective studies are required to fully assess the clinical impact of splenic RT in the transplant setting, especially in combination with other therapeutic strategies. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

CT-163 Outcomes of Hematological Malignancy Patients Who Underwent Haploidentical SC Transplant With ATG of 2 Mg/kg Based Conditioning Regimen

Hematopoietic stem cell transplantation from human leukocyte antigen (HLA)-haploidentical family members (Haplo-HSCT) offers a potential cure for patients with hematological malignancies who lack an HLA-matched donor. Haplo-HSCT with post-transplant cyclophosphamide (PTCY) is associated with induced immune tolerance, rapid hematopoietic recovery, lower graft-versus-host disease (GVHD), and lower non-relapse mortality (NRM). We noticed a high incidence of high-grade GVHD, so we added antithymocyte globulin (ATG) to the Haplo-HSCT transplant platform. Here we review the outcomes of patients who received PTCY and ATG 2 mg/kg (ATG-2). We retrospectively reviewed the medical records of all patients who underwent Haplo-HSCT for malignant hematologic disorders, using myeloablation, ATG-2, and PTCY for GVHD prophylaxis. We analyzed the patient's characteristics and outcomes of the transplant. We used the Kaplan-Meier method to estimate survival probabilities. Statistical analysis was performed with EasyMedStat. Fifty-three-patients were reviewed, 26 (49.1%) males and 27 (50.9%) Females. The majority of patients had AML (60%). Other diagnoses included ALL, CML, MDS, APL, and BPDCN. Seventy-one percent of patients received bone marrow harvested cells and 27% received PBSCT and 2% received both BM and PBSCT. The conditioning was myeloablative in the form of Thiotepa/Busulfan/Fludarabine (73.5%) for myeloid malignancies and Fludarabine/TBI 1000 cGy (26.4%) for lymphoid malignancies. The median duration of follow-up was 15 months. At 12 months, the overall survival (OS) was 73.4% (95% CI: 59.3-83.3), and the relapse-free survival (RFS) was 70.3% (95% CI: 55.6-80.9). 33% of patients developed GII to IV acute GVHD and 17% of patients developed extensive chronic GVHD. There were no cases of primary graft failure (GF), but two patients developed secondary GF. One-third of patients developed hemorrhagic cystitis (33.9%) and the majority of patients (90.5%) developed CMV reactivation. Only two patients developed Veno-occlusive disease (VOD). Haplo-HSCT for hematological malignancies with myeloablative conditioning, PTCY and ATG 2 mg/kg is feasible and associated with favorable OS, and RFS. The risk of GVHD, VOD, and GF is comparable to other case series.

Low-Dose Total Body Irradiation Added to Fludarabine and Busulfan Reduced-Intensity Conditioning Reduces Graft Failure in Patients with Myelofibrosis

Allogeneic hematopoietic cell transplantation (alloHCT) is indicated for patients with intermediate-risk or high-risk myelofibrosis (MF) and remains the sole potential cure. Reduced-intensity conditioning (RIC) is commonly used because of older patient age, comorbidities, and a high incidence of transplantation-related mortality. Patients with MF are at increased risk of graft failure (GF), which is more common with RIC regimens, and is associated with shortened overall survival (OS). Owing to the high rate of GF with conventional fludarabine (Flu) and busulfan (Bu) RIC, we added low-dose total body irradiation (TBI; 200 cGy) for patients with MF. We retrospectively compared alloHCT outcomes in adult patients with MF who received RIC with Flu/Bu/TBI and those who received RIC with Flu/Bu. The primary endpoint was the incidence of GF. Secondary endpoints included time to engraftment, acute and chronic graft-versus-host disease (GVHD), hepatic sinusoidal obstruction syndrome (SOS), nonrelapse mortality, overall response rate, progression-free survival, and OS. Of 33 patients who underwent alloHCT, 8 received Flu/Bu RIC and 25 received Flu/Bu/TBI RIC. GF occurred in 50% of the Flu/Bu recipients (all secondary GF) and in 4% of the Flu/Bu/TBI recipients (1 case of primary GF;relative risk, .08; 95% confidence interval [CI], .01 to .62; P=.0016). GF incidence was similar with related or unrelated donors and in patients who did and did not receive Janus-associated kinase inhibitors prior to alloHCT. Molecular remission and donor chimerism ≥99% were significantly more common with Flu/Bu/TBI. No significant differences in acute GVHD, chronic GVHD, or time to engraftment were observed. SOS occurred in none of the 8 patients who received Flu/Bu and in 6 of the 25 patients who received Flu/Bu/TBI, but this difference did not reach statistical significance. Progression or relapse at 1 year was less common with Flu/Bu/TBI (0% versus 63%; P < .001). The median OS was 49 months for Flu/Bu/TBI recipients and 30.8 months for Flu/Bu recipients (hazard ratio, .98; 95% CI, .33 to 2.88; P=.97). Flu/Bu/TBI resulted in a significant reduction in GF and a significant improvement in the frequency of molecular remission and full donor chimerism compared with Flu/Bu. The addition of low-dose TBI to Flu/Bu successfully mitigates against GF in patients with MF without increased rates of complications.

CD34+ -selected hematopoietic stem cell transplant conditioned with a myeloablative regimen in patients with advanced myelofibrosis.

Allogeneic hematopoietic stem cell transplantation (Allo-HCT) remains the only curative treatment for myelofibrosis (MF). Transplantation in patients with MF is mostly done using a reduced intensity conditioning regimen with calcineurin inhibitors for graft versus host disease (GVHD) prophylaxis. Here we sought to evaluate outcomes of patients who underwent an ex vivo CD34+ -selected allo-HCT using myeloablative conditioning (MAC). Twenty-seven patients were included in this retrospective analysis. All patients were conditioned with busulfan, melphalan and fludarabine and antithymocyte globulin to prevent graft rejection. G-CSF mobilized peripheral blood stem cell grafts were depleted of T-cells using immunomagnetic CD34+ selection by CliniMACS device. Median follow-up among survivors was 50.6 months. The estimated 3-year overall survival, relapse free survival and the combined endpoint of GVHD/relapse free survival were 88% (95% CI, 75-100%), 80% (95% CI, 66-98%) and 74% (95% CI, 59-93%), respectively. The cumulative incidence of grade II-IV acute GVHD at day 100 was 33.3% (95% CI 16.4-51.3%), and two patients suffered chronic GVHD. There were no cases of primary graft failure. However, delayed graft failure occurred in two patients. We conclude that CD34+ selected allo-HCT with a MAC resulted in high survival rates in this cohort of patients with MF.

Granulocyte Transfusions in Patients with Chronic Granulomatous Disease Undergoing Hematopoietic Cell Transplantation or Gene Therapy.

Granulocyte transfusions are sometimes used as adjunctive therapy for the treatment of infection in patients with chronic granulomatous disease (CGD). However, granulocyte transfusions can be associated with a high rate of alloimmunization, and their role in CGD patients undergoing hematopoietic cell transplantation (HCT) or gene therapy (GT) is unknown. We identified 27 patients with CGD who received granulocyte transfusions pre- (within 6 months) and/or post-HCT or GT in a retrospective survey. Twelve patients received granulocyte transfusions as a bridge to cellular therapy. Six (50%) of these patients had a complete or partial response. However, six of 10 (60%) patients for whom testing was performed developed anti-HLA antibodies, and three of the patients also had severe immune-mediated cytopenia within the first 100 days post-HCT or GT. Fifteen patients received granulocyte transfusions post-HCT only. HLA antibodies were not checked for any of these 15 patients, but there were no cases of early immune-mediated cytopenia. Out of 25 patients who underwent HCT, there were 5 (20%) cases of primary graft failure. Three of the patients with primary graft failure had received granulocyte transfusions pre-HCT and were subsequently found to have anti-HLA antibodies. In this small cohort of patients with CGD, granulocyte transfusions pre-HCT or GT were associated with high rates of alloimmunization, primary graft failure, and early severe immune-mediated cytopenia post-HCT or GT. Granulocyte transfusions post-HCT do not appear to confer an increased risk of graft failure.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10875-022-01261-1.

Outcomes of Descemet stripping endothelial keratoplasty in cases of corneal endothelial dysfunction

Automated microkeratome is commonly used to get donor lenticules for Descemet stripping endothelial keratoplasty (DSEK); however, manual dissection of donor lenticules is also being done with good outcomes. The aim of this study was to describe the results of manual DSEK performed in cases of corneal endothelial dysfunction caused due to pseudophakic bullous keratopathy, iridocorneal endothelial syndrome, and postpenetrating keratoplasty graft failure. This was a retrospective observational study. The medical records of all patients with corneal decompensation who underwent DSEK at a tertiary care center performed by the same surgeon were reviewed. A standard DSEK with manually dissected donor lenticules was performed in all cases with the exception of the Descemet membrane not being removed in two cases. A comprehensive ophthalmic examination was performed preoperatively and at each postoperative visit in all patients. Eight eyes of seven patients (four males and three females) were included. The mean age was 64.8 years (range, 49-74 years). The average follow-up was 10.9 months (range, 5-22 months). There was one case of primary graft failure which was managed by repeat DSEK. In the rest, corneas remained clear at the last follow-up. No rebubbling was done as none of the cases showed graft detachment. The preoperative best-corrected visual acuity (BCVA) was 20/2000 or less, and postoperatively, BCVA attained was 20/30 in four eyes and one eye achieved 20/80. Manual DSEK performed in eyes with corneal decompensation allowed rapid restoration of corneal clarity while minimizing intraoperative and postoperative complications.

Reduced-Intensity/Reduced-Toxicity Conditioning Approaches Are Tolerated in XIAP Deficiency but Patients Fare Poorly with Acute GVHD.

X-linked inhibitor of apoptosis (XIAP) deficiency is an inherited primary immunodeficiency characterized by chronic inflammasome overactivity and associated with hemophagocytic lymphohistiocytosis (HLH) and inflammatory bowel disease (IBD). Allogeneic hematopoietic cell transplantation (HCT) with fully myeloablative conditioning may be curative but has been associated with poor outcomes. Reports of reduced-intensity conditioning (RIC) and reduced-toxicity conditioning (RTC) regimens suggest these approaches are well tolerated, but outcomes are not well established. Retrospective data were collected from an international cohort of 40 patients with XIAP deficiency who underwent HCT with RIC or RTC. Thirty-three (83%) patients had a history of HLH, and thirteen (33%) patients had IBD. Median age at HCT was 6.5 years. Grafts were from HLA-matched (n = 30, 75%) and HLA-mismatched (n = 10, 25%) donors. There were no cases of primary graft failure. Two (5%) patients experienced secondary graft failure, and three (8%) patients ultimately received a second HCT. Nine (23%) patients developed grade II–IV acute GVHD, and 3 (8%) developed extensive chronic GVHD. The estimated 2-year overall and event-free survival rates were 74% (CI 55–86%) and 64% (CI 46–77%), respectively. Recipient and donor HLA mismatch and grade II–IV acute GVHD were negatively associated with survival on multivariate analysis with hazard ratios of 5.8 (CI 1.5–23.3, p = 0.01) and 8.2 (CI 2.1–32.7, p < 0.01), respectively. These data suggest that XIAP patients tolerate RIC and RTC with survival rates similar to HCT of other genetic HLH disorders. Every effort should be made to prevent acute GVHD in XIAP-deficient patients who undergo allogeneic HCT.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10875-021-01103-6.

Transplantation of allogeneic cryopreserved hematopoietic cell grafts during the Covid-19 pandemic: A National Marrow Donor Program perspective.

Transplantation of allogeneic cryopreserved hematopoietic cell grafts during the Covid-19 pandemic: A National Marrow Donor Program perspective.

Allogeneic Hematopoietic Stem-Cell Transplantation in Patients with GATA 2 Deficiency: Influence of Donor Stem Cell Source and Post-Transplantation Cyclophosphamide

Background: We recently reported on the single-institution experience with allogeneic hematopoietic stem cell transplantation (HSCT) in 22 consecutive patients with GATA2 deficiency or the MonoMAC syndrome and observed a disease-free survival of nearly 90%. However, despite 10/10 HLA match of matched related donors (MRD) and matched unrelated donors (URD), there was a 25% incidence of grades III-IV acute graft-versus-host disease (GVHD) with tacrolimus/methotrexate (Tacro/MTX). In contrast, there was no grade III-IV acute GVHD in the haploidentical related donor (HRD) recipients, all of whom received GVHD prophylaxis with post-transplantation cyclophosphamide (PT/Cy) followed by tacrolimus/mycophenolate (tacro/MMF). Based on this initial experience, the protocol was subsequently amended to incorporate PT/Cy in all patients. We now report on this expanded cohort of a total of 59 patients, representing the largest experience with HSCT for GATA2 deficiency. Methods: This single-institution study was conducted at the National Institutes of Health Clinical Center between 2013 and 2020 (ClinicalTrials.gov Identifier: NCT01861106). Patients between 12 to 60 years of age were eligible if they had a deleterious mutation in the GATA2 gene, or clinical picture of the MonoMAC syndrome. Although the primary endpoints were engraftment and reversal of the clinical phenotype, a secondary endpoint was added to determine if PT/Cy in the MRD and URD reduced the incidence of grade III-IV aGVHD without compromising the overall and disease-free survival. Immune reconstitution at 100 days, 6, 12, 24, 36 months was analyzed. Results: 59 patients (median age at diagnosis 24 years; IQR 20-32) with GATA2 deficiency or the MonoMAC syndrome underwent allogeneic HSCT. MRD and URD recipients received busulfan for four days (targeted to an AUC 3600-4800) and fludarabine, whereas HRD recipients received two days of low dose cyclophosphamide, 5 days fludarabine, 200cGY total body irradiation, and two or three days of busulfan depending upon the presence or absence of clonal cytogenetic abnormalities. Donor sources included: 11 MRD, 31 URD, and 17 HRD. Median follow-up was 2 years [IQR 1-4], 88% (52/59) are currently alive. Seven deaths have occurred, including: persistent AML (n=1); infection (n=4); poor graft function and cardiac arrest (n=1) and from HPV-associated metastatic cancer (n=1). All of the patients who received HRD transplant are alive. Median time to neutrophil engraftment was 15 days (IQR 13-17) and 19.5 days (IQR 16-25) for platelets. Ninety three percent (55/59) of patients had blood test results after 100 days post-transplant to assess immune reconstitution; eighty one percent (45/55) had normal absolute monocyte counts, 67% (37/55) had normal absolute NK cell counts and 89% (49/55) had normal B cells counts. There was one case of primary graft failure in a recipient of an URD-transplant, and one secondary graft rejection in a recipient of HRD-transplant. Fifty-four percent (32/59) of patients had pre-HSCT myelodysplastic syndrome (MDS), and only two relapsed post-HSCT. Forty two percent (25/59) had abnormal cytogenetics pre-HSCT; amongst 23 patients with serial pre/post bone marrow cytogenetic evaluations, 19 had established normal cytogenetics post-HSCT. Forty five percent (19/42) of MRD/URD patients received Tacro/MTX for GVHD prophylaxis, and 31.5% (6/19) developed grade III-IV acute GVHD (aGVHD). In contrast, 55% (23/42) MRD/URD patients received PT/Cy for GVHD prophylaxis, and none developed grade III-IV aGVHD (p 0.0052). Five percent (1/17) of HRD recipients developed grade III-IV aGVHD. Forty two percent (8/19) of MRD/URD patients who received post-transplant Tacro/MTX had chronic GVHD, 4.3% (1/23) of MRD/URD patients who received PT/Cy developed cGVHD, and 5.8% (1/17) of HRD patients developed cGVHD within the first 2 years post-transplant. Conclusions: Allogeneic HSCT using a busulfan-based regimen in GATA2 deficiency results in nearly a 90% disease-free survival with long-term immune reconstitution. The use of PT-Cy reduced the risk of severe aGVHD and cGVHD and did not increase the risk of relapse or progression of MDS/AML. With earlier recognition of the disease, and the use of PT/Cy more broadly, these results are expected to continue to improve. Disclosures Notarangelo: NIAID, NIH: Research Funding.

Combined Epithelial, Stromal, and Anterior Chamber Ingrowth After Penetrating Keratoplasty

Purpose: To present a case of primary graft failure after penetrating keratoplasty found to have epithelial ingrowth into the host stroma on histopathologic analysis. Methods: This is a single observational case report. Results: We herein describe the clinical course of a case of primary graft failure after penetrating keratoplasty. The corneal button was sent for histopathologic analysis. Analysis of the patient's failed corneal button revealed circumferential epithelial full-thickness wound invasion and stromal epithelial invasion into corneal stroma. Conclusions: Based on histopathologic analysis and this patient's presentation, the stromal ingrowth followed recipient epithelial invasion of the wound and stromal invasion through clefts in the donor corneal edges. Cases of primary graft failure should be assessed for histopathologic evidence of epithelial stromal ingrowth, despite its rarity. To our knowledge, epithelial ingrowth into the corneal donor stroma after penetrating keratoplasty has not been previously reported.

Reduced Intensity Conditioning Regimen with a Variety of Stem Cell Grafts Is Well Tolerated, and Results in Timely and Sustained Donor Engraftment in Patients with a Diversity of Nonmalignant Diseases

<h3>Objectives</h3> To evaluate engraftment, acute graft-versus-host disease (aGVHD), and overall survival of a reduced intensity conditioning regimen. <h3>Methods</h3> From 2011 to 2019, 69 patients (table 1) with nonmalignant conditions (figure 1) underwent hematopoietic cell transplantation (HCT) following a novel reduced intensity conditioning regimen of dose-adjusted alemtuzumab (0.2-2.2 mg/kg), hydroxyurea (30 mg/kg/day), fludarabine (150 mg/m2), melphalan (140 mg/m2) and thiotepa (200 mg/m2) with GVHD prophylaxis of tacrolimus and mycophenolate mofetil. Forty-nine (71%) were enrolled on clinical trial NCT01962415. Grafts were unmanipulated, with the exception of 5 mismatched and/or PBSC grafts that were ex-vivo T-cell depleted. All patients were recipients of their first HCT, except for a patient with relapsed hematophagocytic lymphohistiocytosis, who received second transplant more than 7 years from the first. <h3>Results</h3> Donor neutrophil engraftment occurred in 68 of 69 patients at a median of 14 days (range 9-33) and platelet engraftment (>50K) occurred in 68 of 69 patients at a median of 37 days (range 14-105). Sustained donor chimerism was excellent (figure 2). There was 1 case of primary graft failure (GF) and 4 cases of secondary GF; 4 of 5 patients successfully underwent a second transplant using busulfan-based reduced toxicity conditioning. Patients endured minimal organ toxicity with one case of venoocclusive disease after first HCT which responded to defibrotide, no cases of hemorrhagic cystitis or pericardial effusions, no need for dialysis, and no persistent organ toxicity or failure. Fifteen (22%) developed grade II-IV aGVHD and 6 (9%) developed grade III aGVHD. There was no grade IV aGVHD, no therapy-refractory GVHD, or death due to GVHD. With an average follow up of 5 years (range 97 days-8 years), the overall survival of this cohort is 91%. <h3>Conclusion</h3> This regimen has demonstrated safety and efficacy with a low rate of severe GVHD for 28 unique nonmalignant conditions, including inborn errors of metabolism, immunodeficiencies, and transfusion-dependent anemias.

Non-Myeloablative Bone Marrow Transplant with Post-Transplant Cyclophosphamide Plus Thiotepa Improves Donor Engraftment in Patients with Transfusion Dependent Thalassemia: Results of an International Consortium (VGC2)

<h3>Background</h3> Post-transplant cyclophosphamide (PTCy) enables allogeneic hematopoietic cell transplant (Allo-HCT) across the human leukocyte antigen barrier. Allo-HCT for severe transfusion dependent thalassemia is restricted in its application due to limited donor availability, graft rejection, and regimen-related toxicities. We explored the use of a common non-myeloablative (NMA) conditioning regimens with PTCy based graft-versus-host disease (GvHD) prophylaxis for matched related, haploidentical, and unrelated donors in the setting of a collaborative consortium. <h3>Methods</h3> A multicenter learning collaboration involving 3 centers used an augmented NMA conditioning with PTCy developed by John Hopkins group (Bolaños-Meade, Blood 2012). All patients received common conditioning regimen consisting of ATG 4.5 mg/kg, fludarabine 150 mg/m², cyclophosphamide 29 mg/kg, thiotepa (10 mg/kg on day -7) and TBI 200 cGy. Graft versus host disease (GvHD) prophylaxis was PTCy 50 mg/kg on days +3 and +4, MMF, and sirolimus. To improve engraftment rates, all patients received preconditioning with hydroxyurea 30mg/kg x 60 days (Figure 1). Most patients received G-primed bone marrow as stem cell source. Two patients received matched related donor (MRD), 4 patients haploidentical, and 3 patients matched unrelated donor (I-MUD, 2-mismatched MUD) bone marrow transplants (Figure 2). <h3>Results</h3> A total of 9 patients with transfusion dependent thalassemia were included with a median follow-up time of 371 days. One case of primary graft failure was seen in the haploidentical cohort at D+32; 89% (8/9) patients successfully engrafted. Two cases each of mild gut and skin acute GvHD and one case each of limited gut and skin chronic GvHD were seen in transplanted patients. No cases of grades III-IV acute or severe, chronic GvHD were seen. All patients are alive, thalassemia free survival (TFS) was 100% in the MRD and M/MUD recipients, but 75% (3/4) in the haploidentical cohort. There was no statistical difference between groups in regards to neutrophil or platelet engraftment, age, TNC or CD34+ cell dose. No engrafted patient required long-term immunosuppression therapy, and all remain transfusion independent. <h3>Conclusion</h3> We have shown the feasibility of NMA conditioning with PTCy plus thiotepa for severe transfusion dependent thalassaemia. A phase II study will help determine the optimal regimen with least toxicity and improved thalassaemia free survival.

Cord Blood Transplantation Is an Effective Treatment Option in Patients with Myelodysplastic and Myeloproliferative Syndromes

Background: Few registry studies have investigated the use of cord blood transplantation (CBT) for treatment of patients with myelodysplastic syndrome (MDS) and myeloproliferative disorders (MPN). To date, the outcomes reported have been not encouraging with excess of graft failures [1] and poor disease-free survival (DFS) [2]. The major obstacle to the success of CBT in this high-risk population has been related to the high rate of non-relapse mortality (NRM) due to the delayed time to engraftment. In this single-center study we retrospectively investigated clinical outcomes in patients with MDS and MPN undergoing a CBT. Methods: We reviewed clinical outcomes in 65 consecutive patients with either MDS (n=42) or MPN (n=23) who received a CBT at our institution between 2006 and 2018. The conditioning regimens used consisted of Cyclophosphamide (CY), Fludarabine (FLU), and total body irradiation (TBI) 13.2 Gy (n=16); Treosulfan, FLU, and TBI 2 Gy (n=26); Busulfan, CY, and FLU (n=6); or CY, FLU, and TBI (2 to 4 Gy) (n=17). All patients received Cyclosporine and Mycophenolate Mofetil for graft-versus-host disease (GVHD) prophylaxis. Cord blood units were HLA-typed at the antigen level for HLA-A and B, and high resolution for HLA-DRB1. Disease risk was classified as low to intermediate (n=37) and high to very high (n=28). Cytogenetics risk at diagnosis was favorable, intermediate and unfavorable in 11 (17%), 33 (51%) and 21 (32%) patients, respectively. Among patients with MDS, the R-IPSS score was low in 6 (14%), intermediate in 18 (43%), high in 8 (19%), and very-high in 10 (24%). Engraftment, relapse, NRM, and acute GVHD were calculated using cumulative incidence estimates adjusting for the appropriate competing risks. DFS and overall survival (OS) were assessed using the Kaplan-Meier method. Results: Patient characteristics are shown in Table 1. Median follow-up was 4.2 years (range, 0.5-12). The median age and weight were 46 years (range, 1-71) and 71 kg (range, 10-116). Six (9%) patients had failed a prior HCT. 56 (86%) patients received 2 cord blood units to achieve the required cryopreserved cell dose. The median cell doses infused were 2.6 x 107 (range, 1.4-15) TNC/kg and 0.12 x 106 (range, 0.02-0.78) CD34+ cells/kg. Neutrophils (&gt;500 for 3 days) and platelet (&gt;20x109/L for 7 days transfusion free) engraftment occurred at a median time of 20 days (range, 6-89) and 35 days (range, 13-85), respectively. There were only 4 (6%) cases of primary graft failure, 2 of which were patients with MDS and 2 patients with MPN, and no cases of secondary graft failures. 76% of MDS patients and 52% of MPN patients achieved platelet engraftment by day 100. OS at 3 years was 60% (95% Confidence Interval, CI: 47-71) and specifically was 63% (95% CI: 47-76) for MDS patients and 55% (95% CI: 32-73) for MPN patients. Disease free survival at 3 years was 54% (95% CI: 41-66) with a cumulative incidence of relapse of 21% (95% CI: 11-32). The cumulative incidence of NRM at day 100 and at 3 years were 9% (95% CI: 4-17) and 25% (95% CI: 15-36), respectively. No differences in DFS, relapse incidence, and NRM were seen between MDS and MPN patients (Table 2). The cumulative incidence of acute GVHD grade II-IV and III-IV were 74% (95% CI: 61-82) and 21% (95% CI: 12-32), respectively. Seventeen (26%) patients developed late acute GVHD at a median time of 186 days (range, 101-379), and 10 (15%) had overlap syndrome. Twenty-three (35%) patients were diagnosed with classical chronic GVHD: 18 (27%) with mild, 3 (5%) with moderate, and only two (3%) with severe grade. Conclusions: The results presented herein demonstrate that in patients with MDS and MPN undergoing CBT sustained engraftment was achievable without excessive graft failures. The rates of OS and DFS at 3 years were extremely encouraging and similar to what was observed after matched related and unrelated donors' transplants. [3,4]. Overall, our data suggest that CBT should be considered as a valid option for this high-risk population in case of lack of conventional donors. Disclosures Delaney: Biolife Solutions: Membership on an entity's Board of Directors or advisory committees; Nohla Therapeutics: Employment, Equity Ownership. Milano:ExCellThera: Research Funding; Amgen: Research Funding.

Learning Descemet Membrane Endothelial Keratoplasty: A Survey of U.S. Corneal Surgeons.

The transition to Descemet membrane endothelial keratoplasty (DMEK) is frequently challenging, requiring the adoption of new techniques, skills, and methods. We sought to draw on surgeons' initial experiences with DMEK to characterize the learning curve associated with this procedure and identify factors that could be linked to the frequency of primary graft failure (PGF) in the first 10 cases. We invited corneal surgeons based in the United States who started performing the DMEK procedure within the past 2 years to answer a 12-question survey using an online survey platform. We analyzed quantitative and qualitative data. A Fisher exact test was used to determine whether preoperative approaches to preparation were associated with decreased PGF rates. A total of 100 US-based corneal surgeons replied from 34 of 50 states. Of these, 68% reported that DMEK comprised a majority of their endothelial keratoplasty cases. Approximately half of surgeons (52%) had performed more than 20 DMEK cases by the time of the survey, and 51% felt equally comfortable performing DMEK relative to Descemet stripping endothelial keratoplasty. Among the respondents, 37% answered that they had experienced PGF in the first 10 cases. Scrubbing in with an experienced colleague before surgery was associated with a decreased likelihood of at least one case of PGF (31%, P = 0.049), but not participation in a wet lab with an experienced instructor or mentor (38%, P = 0.50), nor having an eye bank representative present in the operating room (43%, P = 0.886). The collective experience of 100 surgeons beginning DMEK confirms the importance of mentorship and that the accompaniment of an experienced colleague during the learning curve is associated with lower rates of PGF.

Descemet Membrane Endothelial Keratoplasty for Corneal Decompensation Secondary to Phakic Intraocular Lenses.

Purpose To describe the surgical technique and clinical outcomes of bilensectomy (pIOL explant and phacoemulsification), followed by DMEK performed for bullous keratopathy secondary to pIOL. Methods Seven eyes of seven patients, who developed corneal decompensation after pIOL implantation, underwent bilensectomy followed by DMEK in a two-step procedure. Main outcome measures included uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), refraction, endothelial cell density (ECD) at 1, 3, 6, and 12 months, and intraoperative and postoperative complications. Results DMEK was performed at a mean time of 9.83 ± 8.23 months after bilensectomy. BCVA (log MAR) improved in all eyes, increasing from 1.11 ± 0.78 preoperatively to 0.54 ± 0.21, 0.28 ± 0.23, 0.21 ± 0.21, and 0.17 ± 0.17 at 1, 3, 6, and 12 months after DMEK. One year after surgery, mean spherical equivalent and cylinder were −0.70 ± 0.92 D and −1.50 ± 0.54 D, respectively. ECD decreased by 62 ± 4%, 69 ± 4%, 74 ± 4%, and 77 ± 3% at 1, 3, 6, and 12 months after DMEK. There was one case of primary graft failure and no other postoperative complications. Conclusions The two-step technique bilensectomy followed by DMEK is a feasible technique for the management of bullous keratopathy secondary to pIOL, providing a fast visual recovery with good visual and refractive results.

Results After Implementing a Program of Intensive Care to Facilitate Organ Donation

A program of intensive care to facilitate organ donation (ICOD) represents one of the ways to increase donation rate following brain death (BD). ObjectivesTo analyze the impact and cost-effectiveness of setting up an ICOD strategy. MethodRetrospective cases of BD donors from the Spanish region La Rioja were included, after implementation of an ICOD program (2011–2016). This was activated in cases of devastating neurologic injury where treatment had been rejected following therapeutic futility criteria. Follow-up of kidney and liver transplant patients with the obtained grafts was carried out. ResultsA total of 134 potential donors were admitted to intensive care unit (ICU), of whom 106 were selected under the ICOD strategy. BD was diagnosed in 108 cases (25 conventional donors, 83 ICOD donors). A total of 21.6% of potential ICOD donors did not evolve to BD, subsequently dying in the ICU. ICOD cases accounted for more than 50% of donors each year. This cohort had an average stay of 2.4 days in the ICU and accounted for a small proportion of total ICU admissions. A total of 68 (81.9%) ICOD donors were finally effective and 146 grafts were extracted, the majority being abdominal organs (liver and kidney). Probability of survival 1 year after liver transplant (ICOD donor) was 90.9%, with 1 case of primary graft failure. Survival 1 year after kidney transplant (ICOD donor) was 92.7%. No differences were detected in survival rates of kidney and liver transplant patients regarding donor type (ICOD vs conventional). ConclusionsImplementation of an ICOD program allows an increase in the pool of valid and quality grafts for transplant as well as implying a minimum consumption of intensive medicine resources. The results in transplant patients support this strategy.

New Graft Insertion Device for Descemet Stripping Automated Endothelial Keratoplasty.

Corneal endothelial dysfunction is a major indication for corneal graft surgery worldwide, and although surgical intervention through a range of posterior lamellar surgeries has proven to be hugely beneficial, challenges remain. This is especially so where the anterior chamber is relatively shallow, as is often the case in the Asian population, though not exclusively so. In this study, we introduce a new insertion device to deliver endothelial graft tissue for Descemet stripping automated endothelial keratoplasty (DSAEK). A new surgical tool was designed and manufactured so as to enable a 1-step insertion of corneal graft tissue into the anterior chamber based on a pressure-flow concept, rather than the a pull-through one. This was tested ex vivo to assess endothelial cell damage, and then performed in 12 first-in-human surgeries. Precut DSAEK lenticules implanted in donor corneas ex vivo through the new technique showed that less endothelial cell damage occurs compared with a pull-through technique. Grafts were successful in all patients receiving the new surgery, with no cases of primary graft failure. The newly developed DSAEK inserter is a simple and useful tool for endothelial graft delivery, lessening intraoperative mechanical stress on the graft tissue.