Hemopoietic Stem Cell Transplantation Research Articles

Substrate Reduction Therapy for Krabbe Disease: Exploring the Repurposing of the Antibiotic D-Cycloserine.

Krabbe disease is a lysosomal storage disease that is caused by a deficiency in galactosylceramidase. Infantile onset disease is the most common presentation, which includes progressive neurological deterioration with corresponding demyelination, development of globoid cells, astrocyte gliosis, etc. Hemopoietic stem cell transplantation (HSCT) is a disease modifying therapy, but this intervention is insufficient with many patients still experiencing developmental delays and progressive deterioration. Preclinical studies have used animal models, e.g., twitcher mice, to test different experimental therapies resulting in developments that have led to progressive improvements in the therapeutic impact. Some recent advances have been in the areas of gene therapy and substrate reduction therapy (SRT), as well as using these in combination with HSCT. Unfortunately, new experimental approaches have encountered obstacles which have impeded the translation of novel therapies to human patients. In an effort to identify a safe adjunct therapy, D-cycloserine was tested in preliminary studies in twitcher mice. When administered as a standalone therapy, D-cycloserine was shown to lengthen the lifespan of twitcher mice in a small but significant manner. D-Cycloserine is an FDA approved antibiotic used for drug resistant tuberculosis. It also acts as a partial agonist of the NMDA receptor, which has led to numerous human studies for a range of neuropsychiatric and neurological conditions. In addition, D-cycloserine may inhibit serine palmitoyltransferase (SPT), which catalyzes the rate-limiting step in sphingolipid production. The enantiomer, L-cycloserine, is a much more potent inhibitor of SPT than D-cycloserine. Previously, L-cycloserine was found to act as an effective SRT agent in twitcher mice as both a standalone therapy and as part of combination therapies. L-Cycloserine is not approved for human use, and its potent inhibitory properties may limit its ability to maintain a level of partial inactivation of SPT that is also safe. In theory, D-cycloserine would encompass a much broader dosage range to achieve a safe degree of partial inhibition of SPT, which increases the likelihood it could advance to human studies in patients with Krabbe disease. Furthermore, additional properties of D-cycloserine raise the possibility of other therapeutic mechanisms that could be exploited for the treatment of this disease.

Changing Trends of Candida Species and Antifungal Susceptibility Profile of Candida Bloodstream Isolates: A 5-Year Retrospective Survey

Background: Candida species have emerged as one of the most common causes of bloodstream infections (BSIs). There are limited data on the distribution of Candida spp. and susceptibility by year. Objectives: In this study, we analyzed changes in the distribution of Candida spp. and their antifungal susceptibility profiles from blood cultures. Methods: Records from January 2016 to December 2020 were obtained from the microbiology laboratory in Istanbul. Antifungal susceptibility tests were performed using the VITEK 2 compact system and evaluated according to EUCAST breakpoints. A total of 241 unique candidemia episodes were included in this study. Results: Candida albicans was the predominant pathogen (n = 95, 39.42%), followed by C. parapsilosis (n = 82, 34.02%), C. glabrata (n = 18, 7.47%), C. tropicalis (n = 17, 7.05%), C. krusei (n = 15, 6.22%), and other Candida spp. (n = 14, 5.79%). There was no statistically significant difference in the percentage of episodes of Candida spp. After data analysis, a tendency to shift from C. albicans to C. parapsilosis was observed in the period analyzed in this study. Candida albicans was the most common species in intensive care units (ICUs), hematology and hemopoietic stem cell transplantation units, and surgical clinics, with C. parapsilosis predominant in medical clinics. In general, micafungin susceptibility was the highest, and fluconazole was the lowest. There was reduced sensitivity to fluconazole and voriconazole for C. albicans and C. parapsilosis over 5 years. Conclusions: Detecting changes in the distribution of Candida spp. and antifungal susceptibility over time will lead to the selection of appropriate empirical therapy and monitor phenomena of antifungal resistance. Empirical treatment with antifungal agents is associated with high costs, toxicities, and risk of antifungal resistance. Therefore, it is mandatory to determine and monitor Candida spp. and antifungal susceptibility testing to select appropriate antifungal agents.

Prevalence of Chronic Oral GVHD in a Cohort of Egyptian Pediatric Patients Following Allogenic Hemopoietic Stem Cell Transplantation

The current research aims at screening a cohort of Egyptian pediatric patients after receiving allogenic hemopoietic stem cell transplant (HSCT) in order to detect prevalence and risk factors of oral chronic graft versus host disease (cGVHD).

Effects Of Chamomile In The Treatment Of Oral Mucositis Among Patients Undergoing Chemotherapy And Radiotherapy: A Systematic Review

Background: The Most common inflammatory condition seen among patients undergoing chemotherapy and radiotherapy and in patients receiving hemopoietic stem cell transplant is Oral Mucositis. Many treatments were introduced to prevent oral mucositis where chamomile is one among them where it shows anti-inflammatory properties. Aim: To assess the efficacy of chamomile in the treatment of oral mucositis when compared to other treatments. Methods: A literature review search was performed using mesh terms like oral mucositis and chamomile in Cochrane, Science direct, PubMed, Scopus, Lilacs. Among them a total of 430 articles were screened among which the full text articles are 8 and articles taken for qualitative analysis are 5 articles. PRISMA guidelines are used to report this review article. And five randomized controlled trails were considered for this review process. Results: All the studies showed positive results in the treatment of oral mucositis by using chamomile. Conclusion : In the available literature reviews, Oral Mucositis among patients undergoing chemotherapy and radiotherapy was found to be treated effectively using chamomile .

Complex Clonal Evolution Can Occur Following Transplantation for Transfusion Dependent Thalassaemia in the Context of Mixed Myeloid Chimerism and Reduced Conditioning Regimens

Haemopoietic stem cell transplantation (HSCT) is a well-established treatment modality for the cure of transfusion dependent thalassaemia (TDT) and sickle cell disease (SCD). Clonal evolution has recently been identified as a concerning event in the setting of mixed chimerism and/or ineffective haemopoiesis following conventional bone marrow transplantation and gene therapy for haemoglobinopathies. This has so far been restricted to SCD only, with the presumption that despite both conditions sharing an ineffective erythropoietic marrow compartment, there may be inflammatory and hypoxic differences enabling clonal evolution, in addition to the different exposure to hydroxycarbamide as a therapeutic agent. However, there is a need to investigate whether this may also be an occurrence in TDT.From 2011 to 2021, over a ten-year period, sixty-five consecutive paediatric patients received a sibling HSCT (n=55) or a haploidentical HSCT (n=10) for TDT in our institution. Conditioning intensity was minimised at the start of this cohort in order to limit toxicity and late effects, abandoning the use of Bu/Cy, which resulted in approximately 50% of the patients having stable mixed chimerism long-term. Sibling HSCT was conditioned with fludarabine 160 mg/m 2, treosulfan 42 g/m 2, thiotepa 10 mg/kg and ATG (Thymoglobulin) or alemtuzumab, and received GvHD prophylaxis with ciclosporin and MMF. Haploidentical HSCT was conditioned with fludarabine 150 mg/m 2, cyclophosphamide 30 mg/kg, TBI 2 or 4 Gy, and ATG 4.5 mg/kg (thiotepa 10 mg/kg added if TBI 2 Gy only) with GvHD prophylaxis provided by two doses of post-transplantation cyclophosphamide 50 mg/kg, sirolimus and MMF. All patients had pre-transplantation endogenous haemopoiesis was suppressed pre-transplantation with hypertransfusions for a minimum of 8 weeks, and/or the use of hydroxycarbamide and azathioprine. GvHD prophylaxis was provided with ciclosporin and MMF. All patients were Pesaro class I or II at the time of transplantation. The median age was 5 years (2 - 19). The median survival was 26.8 months (2.6-101.8). The OS was 93.8% and DFS was 89.2%.Three patients in this cohort developed clonal evolution in the context of myeloid mixed chimerism identified due to the development of cytopenias and transfusion dependence. All patients had a complex karyotype and it involved deletion of chromosome 7: •Patient 1 had a sibling BMT at 3 years and 2 months. Day +28 chimerism was >95% in whole blood and 95% in T cells. The myeloid fraction had a progressive reduction from day +60 onwards. At 15 months post-transplantation clonal evolution was identified [18% ring sideroblasts, 46;XY, del (7) (q22 q34) [5]/46;XY [5], chimerism 13% donor in whole marrow and 41% marrow T cells. Two months later he became red cell transfusion dependence. A second BMT with busulfan based conditioning resulted in long-term cure.•Patient 2 had a sibling BMT at 3 years and 8 months of age. Day +28 chimerism was 99% donor in whole blood and 99% donor in T cells. Day +161 post-transplantation he started requiring erythropoietin support to maintain him transfusion independent and on day +217 we first identified in the bone marrow the appearance of myeloid mixed chimerism (75% donor in whole marrow and 91% marrow T cells) and complex clonal evolution involving -7 and FISH identified deletion of one copy of KMT2E (7q22) and MET (7q31) detected [16/200]. The patient is under monitoring at present with a progressive reduction of the size of the abnormal clones.•Patient 3 had a haplo BMT at 5 years and 8 months. Day +28 chimerism was 97% donor in whole blood and 99% donor in T cells. She developed mixed myeloid chimerism following cessation of immunosuppression on day +206: 86% donor whole blood and 99% donor in T cells. At 22 months post-BMT she started to require transfusion and a complex clonal evolution involving deletion 7 in her bone marrow when the chimerism was 42% donor whole blood and 81% donor marrow T cells. FISH identified deletion of one copy of KMT2E(7q22) and MET(7q31) detected[22/100]. She is being prepared for a second bone marrow transplant.In conclusion, complex clonal evolution also occurs post HSCT in TDT, at least in the context of reduction of conditioning intensity and development of mixed myeloid chimerism. This finding warrants further investigation and may have significant implications for the design of both conventional HSCT and gene therapy strategies. DisclosuresNo relevant conflicts of interest to declare.

Incidence and Risk Factors Associated with Fatal Graft Vs Host Disease after Solid Organ Transplantation in United Network of Organ Transplant Database

INTRODUCTIONGraft vs host disease (GVHD) is a rare complication after solid organ transplantation ( ̴ 1-2% with liver and ̴ 5.6% with intestines), but is associated with high mortality (70-80%). In contrast to GVHD following hemopoietic stem cell transplant, bone marrow infiltration by donor T lymphocytes leading to cytopenia ( ̴ 80%) is a common manifestation of GVHD after solid organ transplantation (Murali et. al., 100(12), Transplantation, January 2016). The risk factors associated with GVHD occurring after solid organ transplantation have not been well characterized, but single institution studies have suggested donor/recipient (D/R) HLA mismatch, ABO incompatibility and gender mismatch playing important roles. However, some studies have identified that similarities in HLA type which permit mismatches unrecognized by the recipient as a common mechanism preventing rejection of donor lymphocytes, which then can cause GVHD in the recipient. In order to evaluate potential risk factors, we reviewed the transplant data of patients in whom GVHD was listed as the cause of death from United Network of Organ transplant database (UNOS), the database that contains all US organ transplant data.METHODSFrom the UNOS database we obtained information of patients that underwent liver or intestinal transplantation between 1987-2020 in the US. The patients for whom GVHD was reported as the cause of death were identified. Baseline D/R and transplant variables were collected. Patient or transplant related characteristics were presented via descriptive statistics. Corresponding P-values were determined using Chi-square test for categorical variables and two-sample t-test for continuous variables. The incidence of mortality caused by GVHD was estimated using the cumulative incidence method, accounting for non-GVHD related death as a competing risk. All statistical tests were two sided, and a P-value < 0.05 was considered significant.RESULTSOf a total of 179,355 patients that underwent liver transplantation, 216 (0.1%) patients had GVHD identified as the primary cause of death (GVHD group). The HLA mismatch information was available in 86,434 patients (48.2%). HLA mismatch was grouped into low level (0-3) and high level (4-6). Low level HLA mismatch was 24.6% in the GVHD group compared to 16.2% in patients that are alive or died of non-GVHD related causes (non-GVHD group). High level mismatch was 75.4% in GVHD group and 83.8% in the non-GVHD group (P=0.013). Other risk factors including gender mismatch (40.3% vs 42.5%, P=0.536), ABO incompatibility between D/R (0.5% vs 1.4%, P=0.42) and use of live donors (1.9% vs 4.3%, p= 0.09) were similar between the two groups. Patients in the GVHD group were older with median age of recipient being 59 years compared to 53 years in the non-GVHD (P<0.001). Graft failure was more common in the GVHD group compared to non-GVHD group (33.8% vs 17.1%, P<0.001).Of a total of 3,153 patients that underwent intestinal transplantation, 20 (0.6%) patients had GVHD identified as the primary cause of death (GVHD group). The HLA mismatch information was available in 2859 patients (90.6%).The high-level HLA mismatch (83.3% vs 84.7%, P=0.749), gender mismatch (40% vs 47.1%, P=0.655) and ABO incompatibility (0% vs 0.2%, P=0.757) between D/R were similar between the GVHD group and non-GVHD group among intestinal transplant patients.ConclusionsIn patients that undergo hematopoietic stem cell transplant, HLA and gender mismatch between D/R have been recognized as risk factors for GVHD. Based on the largest analysis of solid organ transplant database, traditionally considered GVHD risk factors like HLA and gender mismatch between D/R do not appear to be significantly associated with severe GVHD leading to death. Recipient age and graft failure are significantly associated with GVHD related deaths in liver transplant patients. These findings suggest that other risk factors for severe GVHD leading to death after solid organ transplant than those previously reported in single institution studies should be examined and underscore the need for additional studies. [Display omitted] DisclosuresGrunwald: Med Learning Group: Other; Agios: Consultancy; Astellas: Consultancy; Daiichi Sankyo: Consultancy; Janssen: Research Funding; Amgen: Consultancy; Pfizer: Consultancy; PRIME: Other; PER: Other; Karius: Consultancy; Sierra Oncology: Consultancy; Blueprint Medicines: Consultancy; Incyte: Consultancy, Research Funding; AbbVie: Consultancy; Bristol Myers Squibb: Consultancy; Stemline: Consultancy; Gilead: Consultancy; Cardinal Health: Consultancy; Trovagene: Consultancy; MDEdge: Other. Copelan: Amgen: Consultancy.

Efficacy and Safety of Eltrombopag Combined with Cyclosporine As First-Line Therapy in Adults with Severe Acquired Aplastic Anemia: Results of the Interventional Phase 2 Single-Arm Soar Study

Efficacy and Safety of Eltrombopag Combined with Cyclosporine As First-Line Therapy in Adults with Severe Acquired Aplastic Anemia: Results of the Interventional Phase 2 Single-Arm Soar Study

Third-Party Partially HLA Matched Fungus-Specific T-Cells (FSTs) Used to Treat Invasive Fungal Infection (IFI) with Scedosporium Aurantiacum after Allogeneic Hemopoietic Stem Cell Transplant (aHSCT)

IntroductionInvasive fungal infection (IFI) is a potentially devastating complication after allogeneic stem cell transplantation (aHSCT). Breakthrough infections are an increasing threat. The adoptive transfer of fungus-specific T cells (FSTs), analogous to virus specific T-cells for viral reactivation, may improve clinical outcomes but the delay involved in generating FSTs from the stem cell donor is problematic for this type of adoptive cell therapy. We created a bank of FSTs from normal donors for use in patients with post-transplant IFI. Here we describe the first use of partially HLA matched 3 rd party FSTs to treat IFI in a patient after aHSCT.MethodsFSTs were manufactured by stimulating G-CSF primed apheresis products overnight with monocyte derived dendritic cells pulsed with lysates from Aspergillus terreus and Candida krusei. CD137 expressing cells were isolated and cultured with CD137 negative feeders in medium supplemented with IL-2, IL-7 and IL-15 for 12 days prior to assessment of target specificity and HLA restriction. Cells consisted principally of CD4 + lymphocytes secreting TNF-α, interferon-γ and IL-17 in response to fungal antigen stimulation. Standard release criteria were applied. We commenced a phase 1 cell dose escalation trial to assess the safety and efficacy of partially HLA-DR matched 3 rd party FSTs from a cryopreserved bank in patients with proven or probable IFI after aHSCT.ResultsPatient A is a 27 year old female who underwent a myeloablative sibling haploidentical transplant for Philadelphia negative B-ALL in second remission. At day 100 she developed grade III lower GI GVHD requiring methylprednisolone and ruxolitinib for steroid dependent disease. Subsequent CMV reactivation was treated with ganciclovir. Cough in association with pulmonary infiltrates followed, and a bronchoalveolar lavage grew Scedosporium aurantiacum, Clavispora lusitania and Aspergillus fumigatus. She developed severe headache and MRI imaging showed a thin rim-enhancing 38x37 mm lesion within the right frontal lobe with moderate vasogenic oedema. Surgical drainage yielded 20 ml of frank pus that grew Scedosporium aurantiacum.Antifungal therapy was started with vorinconazole, terbinafine, amphotericin and later caspofungin. Serial imaging after 12 days showed two new hyperdense foci representing extension of infection, consistent with worsening headaches. The patient received a single infusion of 3 rd party FSTs at a dose of 1 x10 6/m 2 at day 170 post-transplant while continuing antifungal therapy with vorinconazole and terbinafine. The product consisted of 94.1% CD4 +, 3.5% CD8 + T-cells and 1% NK cells and contained CD4 + T-cells responsive to both A. terreus and C. krusei antigens presented by HLA DR*03:01 shared between product and patient. There were no infusion related adverse events. Corticosteroids and calcineurin inhibitors were continued. Within one week of FST infusion there was an increase in the number of naïve and central memory CD4 + T-cells in blood and a fall in the number of CD4 + and CD8 + T-cells expressing Tim3. Over the following 3 months, there was a gradual rise in the number of CD4 + Tem and CD4 + Temra with a later and less pronounced rise in the analogous CD8 + populations. Serial imaging demonstrated rapid regression of the pulmonary abnormalities and gradual regression of the cerebral lesion at day 150 following FST infusion. 279 days after transplant and 109 days after infusion of FSTs, the patient developed worsening of headache and MRI confirmed rupture of the abscess into the right ventricle. Headache gradually resolved and the patient was discharged from hospital 329 days after transplant with ECOG 1 and no neurological abnormalities. However she was readmitted 13 days later with more severe headache with repeat imaging confirming raised intracranial pressure. CSF showed no evidence of fungi by PCR or culture. A CSF shunt was inserted and the patient remains well.ConclusionWe report the first infusion of 3 rd party partially HLA DR matched fungus-specific T-cells for disseminated fungal infection following allogeneic stem cell transplantation. These data demonstrate the feasibility of this approach. The patient's favourable clinical outcome and phenotyping results suggest that the initial cell dose level is safe and may be associated with immune alterations that promote anti-fungal activity. Further trial recruitment is ongoing. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Early Administration of Partially HLA Matched Third Party Virus-Specific T-Cells in Conjunction with Antiviral Treatment for Initial Viral Infection after Allogeneic Stem Cell Transplant Is Safe and Leads to High Rates of Viral Control

Introduction:Reactivation of viruses such as cytomegalovirus (CMV) or Epstein Barr virus (EBV) after allogeneic hemopoietic stem cell transplant (aHSCT) is associated with increased non relapse mortality and a requirement for antivirals with mainly hemopoietic and renal toxicities that can further compromise transplant outcomes and increase health care costs. The use of 3 rd party virus specific T cells (VSTs) has been effective in treating recurrent and refractory viral reactivation after transplant and leads to rapid restoration of viral immunity. We investigated whether early administration of 3 rd party VSTs together with antiviral therapy could safely enhance immune recovery and improve viral control in patients requiring treatment for their initial CMV and EBV infection after aHSCT.Methods:We performed a single arm phase 1 clinical trial in which aHSCT patients requiring treatment for their first CMV or EBV reactivation (or EBV driven malignancy) received infusions of partially HLA matched 3 rd party VSTs within 7 days of commencing standard antiviral treatment. Patients were required to have a viral copy number of at least 1,000 copies/mL for CMV, 10,000 copies/mL of blood for EBV, or proven tissue infection irrespective of copy number for treatment initiation. T cell products were expanded from G-CSF stimulated aphereses from normal donors following peptide stimulation and CD137 magnetic bead selection. T cells were cultured for up to 12 days before specificity testing and cryopreservation. Patients were eligible to receive up to 4 doses of VSTs at 4 week intervals with products selected with a minimum of 1 of 6 HLA matches at HLA-A, -B and -DRB1 with antiviral activity demonstrated through the shared HLA molecule. The primary endpoint of the study was infusion safety.Results:Thirty aHSCT patients were treated with 1-4 VST infusions (27 CMV, 3 EBV) commencing at a median of 4 days after initiation of antiviral treatment. 27 patients were transplanted for hematological malignancies, 3 for immune deficiencies. Conditioning was myeloablative in 12 patients and the majority of patients (22/30) received in vivo T cell depletion. 7/27 CMV seropositive recipients were transplanted from CMV seronegative donors. A total of 41 infusions were given, most frequently targeting antigens presented through shared HLA molecules A2 and/or B7. All infusions were administered at a cell dose of 2 x 10 7/m 2. VST products were CD3 + (median 97.9%, range 96.2 - 99.4%), with median percentage of CD3 +CD8 + 85.8% (range 23.2 - 95.5%). There was one infusion related adverse event consisting of fever that resolved rapidly after admission and antibiotics. Overall viral response rate was 100% with a complete response rate of 94% (Figure 1). Of the 28 patients who achieved a CR (after either 1 or 2 infusions), 22 remained virus PCR negative (n = 8) or below the limit of quantitation (n = 14) for the duration of follow up. 3 patients had brief episodes of quantifiable reactivation not requiring additional therapy and 3 patients required a second infusion following initial CR. All remained PCR negative after their 2 nd CR. All 3 patients treated for EBV PTLD achieved sustained CR. Overall rates of acute and chronic GVHD post-infusion were 33% (10/30) and 20% (6/30) respectively (grade IIII/IV aGVHD 10%, severe cGVHD 7%). VST infusion was associated with a reduction in activation and inhibitory marker expression on CD4 + and CD8 + lymphocytes within the first 30 days and recovery of CD8 + (and more slowly CD4 +) CD45RA -CD62L - effector memory cells. Within the first 100 days after infusion there was an increase in interferon-γ responsiveness of blood lymphocytes. CMV and EBV specific tetramer positive T cells were detected comprising up to 13% of CD8 + cells for up to 6 months post infusion. At 1 year post transplant, non relapse mortality was 10%, cumulative incidence of relapse was 7% and overall survival was 87%.Conclusion:The combination of traditional antiviral treatment and early administration of 3 rd party VSTs is safe and achieves high rates of viral control without evidence of increased acute or chronic GVHD and with evidence of enhanced immune responses to viral antigens. 1 year overall survival was high with low rates of non relapse mortality and relapse. These encouraging results require confirmation in a prospective randomized study comparing best available therapy with best available therapy combined with early VST administration. [Display omitted] DisclosuresRitchie: Novartis: Honoraria; BMS: Research Funding; Takeda: Research Funding; CRISPR Therapeutics: Research Funding; Amgen Inc: Honoraria, Research Funding; CSL: Honoraria.

Acute Lymphoblastic Leukaemia in Johannesburg, South Africa: The State-Sector Experience

IntroductionLymphoblastic leukemia (ALL) is a neoplasm of immature lymphoid cells of either B- or T-cell lineage. B-ALL is the more common (particularly in childhood), and has a number of described recurrent genetic abnormalities with distinct clinic-pathological associations. T-ALL comprises a larger proportion of adult ALL (18-23%) than childhood cases (7-15%) in high income countries, and is genetically heterogeneous without clear prognostic associations with genetic subtypes. The frequency of T-ALL and the genetic landscape of B-ALL show regional variation. T-ALL is common among African American children (~25%), but seen infrequently in Asia (~7% of childhood cases). In B-ALL, the translocation t(12;21) and hyperdiploidy predominate among children in Europe and the USA, while KMT2A rearrangement and the translocation t(9;22) are relatively more common in Asia. There is a paucity of literature regarding ALL in Africa; the distribution of its subtypes (B vs T), its genetic composition and outcomes are not known. This study aimed to characterize ALL diagnosed in the state-sector hospitals of Johannesburg, South Africa (SA).MethodsCases diagnosed with ALL in the flow cytometry laboratory at Charlotte Maxeke Johannesburg Academic Hospital (which provides diagnostic immunophenotyping services to all state-sector hospitals of the southern Gauteng region of SA) between 2016-2019 (42 months) were identified and recorded in a database. Pertinent information was documented from the laboratory information system.ResultsALL was diagnosed in 181 patients over the time period; pertinent clinical information is reported in Table 1. T-ALL was substantially more common than reported elsewhere, comprising 31.5% and 35.2% of childhood and adult ALL, respectively. Differences were evident in the cytogenetic patterns seen in both B- and T-ALL as compared to other parts of the world. In B-ALL the translocation t(1;19) (which occurs in <10% of cases elsewhere) was the most common recurrent genetic abnormality (23.7%), and the t(9;22) had a relatively high frequency in children <13 years (8.8%) (Figure 1). In T-ALL, karyotypic abnormalities were more common than typical (seen in 80.0% of cases vs 50-70% elsewhere), with derangements of chromosome 6q being the most frequent (19%). The translocation t(10;11) (PICALM-MLLT10) and abnormalities involving the TLX1 (HOX11) and TLX3 (HOX 11L2) genes (which are among the more frequent genetic abnormalities reported internationally) were all uncommon, each occurring in only 2.4% of the cases.Disease outcomes were substantially poorer compared to those reported in high income countries, where survival rates in childhood T-ALL range from 60-80% and exceed 90% in B-ALL. At a median follow-up time of 36 months, only 68.2% (B-ALL) and 27.8% (T-ALL) of children <10 years were alive, while mortality rates among adults exceeded 80% in both T- (86.7%) and B-ALL (83.3%). Survival in patients with T-ALL did not differ between those with high vs low risk clinical features (age >10 years, white cell count >100 x10 9/L), and was significantly worse as compared to those with B-ALL (p = 0.01). Relapse was the dominant cause of death in children <10 years (more so in those with T-ALL), while death due to chemotherapy-related neutropenic sepsis was more common in older patients (particularly those with B-ALL) (Figure 2). Factors associated with disease relapse in B-ALL included KMT2A rearrangement and measurable residual disease (MRD) after induction chemotherapy (as defined by non-quantitative, non-allele specific PCR of IgH/T-cell receptor gene rearrangement status and 4 color flow cytometry (both with sensitivities >0.1%)). Notably, the high risk of relapse associated with MRD was not seen in patients with t(9;22), likely due to the use of targeted molecular therapy in these cases. No significant predictors of survival were identified in T-ALL, but the presence of MRD post-induction was associated with early death due to relapse (<12 months).ConclusionALL in SA shows distinct differences in the cytogenetic landscape, disease patterns and outcomes. The cause of the poor survival rates likely includes differences in tumour/host biology, late presentation, restricted access to haemopoietic stem cell transplantation in the SA state-sector, and suboptimal neutropenic support. Although rudimentary, available MRD testing is a valuable risk predictor in both B- and T-ALL. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Consensus guidelines for the diagnosis and management of invasive candidiasis in haematology, oncology and intensive care settings, 2021.

Patients with haematological malignancies, haemopoietic stem cell transplant recipients and patients requiring admission to intensive care settings are at high risk for invasive candidiasis (IC). Over the past decade, there has been increased reporting of non-albicans species and fluconazole resistance in Australia. These guidelines provide updated evidence-based recommendations for the diagnosis and management of IC in adult and paediatric haematology, oncology and intensive care settings. Optimal pharmacological and non-pharmacological management are discussed. Recent studies strengthen the recommendation for an echinocandin agent as first-line therapy for high-risk patients with IC. Mortality benefit has also been demonstrated for non-pharmacological management, including removal of central venous catheters, infectious diseases consultation and use of care bundles. Healthcare facilities managing immunocompromised patient populations should therefore adopt implementation strategies for these multimodal interventions.

Consensus guidelines for the diagnosis and management of invasive fungal disease due to moulds other than Aspergillus in the haematology/oncology setting, 2021.

Invasive fungal disease (IFD) due to moulds other than Aspergillus is a significant cause of mortality in patients with malignancies or post haemopoietic stem cell transplantation. The current guidelines focus on the diagnosis and management of the common non-Aspergillus moulds (NAM), such as Mucorales, Scedosporium species (spp.), Lomentospora prolificans and Fusarium spp. Rare but emerging NAM including Paecilomyces variotii, Purpureocillium lilacinum and Scopulariopsis spp. are also reviewed. Culture and histological examination of tissue biopsy specimens remain the mainstay of diagnosis, but molecular methods are increasingly being used. As NAM frequently disseminate, blood cultures and skin examination with biopsy of any suspicious lesions are critically important. Treatment requires a multidisciplinary approach with surgical debridement as a central component. Other management strategies include control of the underlying disease/predisposing factors, augmentation of the host response and the reduction of immunosuppression. Carefully selected antifungal therapy, guided by susceptibility testing, is critical to cure. We also outline novel antifungal agents still in clinical trial which offer substantial potential for improved outcomes in the future. Paediatric recommendations follow those of adults. Ongoing epidemiological research, improvement in diagnostics and the development of new antifungal agents will continue to improve the poor outcomes that have been traditionally associated with IFD due to NAM.

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy and haemopoietic stem cell transplant recipients, 2021.

Antifungal agents can have complex dosing and the potential for drug interaction, both of which can lead to subtherapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy and haemopoietic stem cell transplant recipients. Antifungal agents can also be associated with significant toxicities when drug concentrations are too high. Suboptimal dosing can be minimised by clinical assessment, laboratory monitoring, avoidance of interacting drugs, and dose modification. Therapeutic drug monitoring (TDM) plays an increasingly important role in antifungal therapy, particularly for antifungal agents that have an established exposure-response relationship with either a narrow therapeutic window, large dose-exposure variability, cytochrome P450 gene polymorphism affecting drug metabolism, the presence of antifungal drug interactions or unexpected toxicity, and/or concerns for non-compliance or inadequate absorption of oral antifungals. These guidelines provide recommendations on antifungal drug monitoring and TDM-guided dosing adjustment for selected antifungal agents, and include suggested resources for identifying and analysing antifungal drug interactions. Recommended competencies for optimal interpretation of antifungal TDM and dose recommendations are also provided.

Oromandibular parafunction in chronic graft-versus-host disease: novel association and treatment approach.

Chronic graft-versus-host disease (cGVHD) complicating allogeneic haemopoietic stem cell transplantation rarely involves the nervous system; oromandibular parafunction has not been previously reported. We describe five patients with cGVHD, presenting with bruxism, limitation of mouth opening, jaw locking, pain and masseter hypertrophy. Pathophysiological mechanisms are discussed. Targeted botulinum toxin injections were an effective treatment with minimal side-effects.

THE ROLE OF SUBPOPULATIONS OF MOBILIZED PERIPHERAL HEMATOPOIETIC STEM CELLS IN THE RESTORATION OF HEMATOPOIESIS DURING HIGH-DOSE CHEMOTHERAPY IN CANCER PATIENTS

Mobilized peripheral hematopoietic stem cells are transplanted to cancer patients as support for high-dose chemotherapy. It is believed that the effectiveness of restoring all hematopoietic sprouts during HSC transplantation depends on the total dose of CD34+ cells. At the same time, CD34+ stem cells are a heterogeneous cell pool, including progenitor cells of different levels of differentiation and different ability to proliferate. Accordingly, it can be expected that the subpopulation composit. We have studied of HSC subsets in 569 specimens of hemopoietic tissue (blood cells and LP cells) from 167 adult cancer patients and on 557 specimens of hemopoietic tissue from 263 pediatric cancer patients. Also, 61 samples of LP from 50 healthy HSC donors were studied. All patients were managed at bone marrow transplantation units of hematology malignancy and oncology department of N.N. Blokhin Cancer Research Center from 1996 to 2014. Peripheral hemopoietic stem cells (HSC) that are transplanted to cancer patients to reduce critical pancytopenia vary in subset composition and include early polypotent precursors (CD38- and/or HLA-DR-, CD90+, CD45-negative), lymphoid precursors (CD10+, CD7+, CD2+, CD19+, CD56+), megakaryocyte- (CD61+) and myeloid-committed precursors (CD117+, CD13+, CD33+). These subsets of early and committed HSC are found in different proportions in cancer patients and normal donors. So, the pool of mobilized HSC is heterogeneous and represented by pluripotent precursors and committed HSC in different proportions that are in variable, rather sophisticated interrelations. Mobilization effect of SC individual subsets is related with disease type. To achieve fast recovery of granulocyte lineages after HSC autologous or allogeneic transplantation one should not focus only on proportion of committed myeloid HSC: optimal HSC content to be transplanted should be in a certain balance.

Influence of CYP2D6 metabolizer status on ondansetron efficacy in pediatric patients undergoing hematopoietic stem cell transplantation: A case series.

Chemotherapy‐induced nausea and vomiting (CINV) is commonly experienced by patients receiving antineoplastic agents prior to hemopoietic stem cell transplant (HSCT). Ondansetron, a 5‐HT3 antagonist metabolized by CYP2D6, is an antiemetic prescribed to treat short‐term CINV, but some patients still experience uncontrolled nausea and vomiting while taking ondansetron. Adult CYP2D6 ultrarapid metabolizers (UMs) are at higher risk for CINV due to rapid ondansetron clearance, but similar studies have not been performed in pediatric patients. We performed a retrospective chart review of 128 pediatric HSCT recipients who received ondansetron for CINV prevention and had CYP2D6 genotyping for 20 alleles and duplication detection. The number of emetic episodes for each patient was collected from the start of chemotherapy through 7 days after HSCT. The average age of the cohort was 6.6 years (range: 0.2–16.7) and included three UMs, 72 normal metabolizers, 47 intermediate metabolizers, and six poor metabolizers. Because UMs are the population at risk for inefficacy, we describe the course of treatment for these three patients, as well as the factors influencing emesis: chemotherapy emetogenicity, diagnosis, and duration of ondansetron administration. The cases described support guidelines recommending non‐CYP2D6 metabolized antiemetics (e.g., granisetron) when a patient is a known CYP2D6 UM, but pediatric studies with a larger sample of CYP2D6 UMs are needed to validate our findings.

2021 Update on allogeneic hematopoietic stem cell transplant for myelofibrosis: A review of current data and applications on risk stratification and management

The number of patients with myelofibrosis (MF) undergoing an allogeneic hemopoietic stem cell transplantation (HSCT) is increasing: in the analysis of the European Group for Blood and Marrow Transplantation (EBMT) the number of MF has increased from 515 in 2014 to 748 in 2018 . This reflects the fact that HSCT is currently the only curative treatment, capable of inducing prolonged disease‐free survival. Nevertheless, several problems prevent more patients from undergoing an allogeneic HSCT: we will be discussing indications for HSCT, comorbidities, splenomegaly, older age and disease phase. Donor type and stem cell source are less of a problem. Several transplant platforms exist, including different strategies for graft versus host disease (GvHD) prophylaxis, Age tailored conditioning regimens need to be implemented, to allow older and fragile patients to undergo an allogeneic HSCT.

Prospective clinical trial of hepatitis B vaccination for children with hematological malignancies: a study on the safety and immunogenicity efficacy

ABSTRACT Children with hematological malignancies are at increased risk of hepatitis B virus infection. This study assessed the immunogenicity and safety profile of HBV vaccination in pediatric hemato-oncological children. A nonrandomized interventional study was conducted from January 2017 to February 2020 in Shanghai, China. Seventy-three pediatric hemato-oncological children with hepatitis B surface antibody (anti-HBs) titers <10 mIU/ml were recruited. The participants received three doses of recombinant HBV vaccine according to the 0-, 1-, and 6- month immunization schedule. Adverse events following immunization and anti-HBs titers (at baseline, 1 month, and 6 months after inoculation) were recorded. Forty-three males and thirty females with median ages of 9.12 and 9.60 years, respectively, were included. The mean anti-HBs titer was 4.88 ± 2.61 mIU/ml, 893.12 ± 274.12 mIU/ml, and 711.45 ± 337.88 mIU/ml at baseline, one month, and six months after inoculation, respectively (P< .001). A total of fourteen adverse events following immunization were reported, and among them, 5 (6.85%), 5 (6.85%), and 4 (5.48%) events were reported after the first, second, and third inoculation, respectively (P= .927). In conclusions, the HBV vaccine is immunogenic and safe in children with hematological malignancies. It is worth noting that the anti-HBs titer was decreased at the 6-month follow-up, and periodic monitoring of the anti-HBs titer accompanied by timely booster vaccination should be carefully considered. Abbreviations: AEFI: Adverse events following immunization; HBV: Hepatitis B virus; Anti-HBs: Antibody against hepatitis B surface antigen; HBsAg: Hepatitis B surface antigen; APC: Antigen-presenting cell; HSCT: Hemopoietic stem cell transplantation; COVID-19: Corona Virus Disease 2019

Mass Cytometry Reveals the Broad Effect of CMV Reactivation on Adaptive and Innate Immune Recovery in HSCT Patients Undergoing Adoptive T Cell Therapy for Viral Infections

Introduction. Adoptive cell therapy (ACT) with virus specific T cells (VST) has been shown to be safe and effective in controlling viraemia in recipients of haemopoietic stem cell transplant (HSCT). Long term engraftment has been demonstrated in some studies but the fate of the transferred cells is not well understood. We hypothesised that the clinical effect of ACT is mediated by interaction of transferred cells with a wide range of innate and adaptive immune cells present in the recipient at the time of ACT treatment. In order to better understand the interaction of stem cell donor-derived and adoptively transferred third-party cells, we sought to apply immune profiling by mass cytometry.Methods. Longitudinal samples from healthy individuals and collected pre- and post-donor derived and third party ACT in HSCT recipients were assessed with a 37 marker panel to identify canonical immune subsets. Cryopreserved peripheral blood mononuclear cells were thawed in batches and stained with metal-labelled antibodies and markers for DNA content and viability. Samples were acquired on the Helios upgraded CyTOF2 mass cytometer. Following sample QC and normalisation of files, viable cells were manually gated to 75 canonical populations with cell subsets enumerated and represented graphically for each sample using visualised t-stochastic neighbour embedding (ViSNE). Cell subsets were expressed as percent of total cells as well as absolute cell number (x109/L) using lymphocyte and monocyte counts from an automated whole blood analyser. This approach was taken to incorporate the large numerical changes that occur in the early months post-HSCT. Mass cytometry data was analysed with unsupervised and supervised clustering algorithms to identify immune signatures. Significance of microarray (SAM) was used to identify the cell subset changes that contributed to the differences in clusters. t-stochastic neighbour embedding (tSNE) and principal component analysis (PCA) were used to correlate immune signatures with clinical variables including patient, transplant and donor baseline characteristics and post-transplant outcomes (including CMV reactivation and disease, acute GVHD, relapse and death).Results. A total of 104 samples from 9 healthy donors and 27 HSCT recipients who received ACT on phase I and II clinical trials were available for analysis. ViSNE revealed highly detailed relationships of the 75 cell subsets within individuals longitudinally and between patients. Unsupervised clustering on all patients and time points and the healthy individuals revealed three distinct immunological signatures (Figure 1). Healthy individuals (signature A) were clearly distinguished from all patients and no patient developed a normal immune profile over the timeframe of the study (up to 6 months post HSCT). In a subset of samples from HSCT recipients a distinct immune phenotype was seen (signature C), characterised by increased CD8+ subsets (CD8em, CD8emra (both of these with and without PD1), CD8+CD57+, CD8+CD31+), NK cell subsets (CD16-, NKp46loCD56lo), NKT cells and plasmacytoid dendritic cells. Of the clinical parameters assessed, signature C was most strongly correlated with CMV reactivation. Signature B showed lower cell numbers overall and included patients with acute GVHD treated with corticosteroids and patients in whom CMV reactivation progressed to CMV disease.Conclusion. Mass cytometry and sophisticated analysis reveal an unprecedented level of detail about the relationships of immune subsets to one another at single time points and their changes over time. This approach identifies distinct global immune signatures involving changes to multiple immune subsets in patients undergoing HSCT and ACT. We have identified an immune signature associated with CMV reactivation that indicates a broader effect of CMV reactivation on immune recovery than previously recognised. As this study was not randomised and did not include a control group who were not treated with ACT, further investigation is required to define the contribution of ACT to the observed immunological changes. This global approach to immunological assessment has the potential to improve understanding of the dynamics of immunological recovery post HSCT. [Display omitted] DisclosuresGottlieb:Indee: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees.

Fludarabine/Treosulfan/Thiotepa/ATG Conditioning for Related Transplantation in b Thalassaemia Major Leads to Early and Sustained Engraftment with Low Incidence of VOD and GvHD but a High Rate of Long-Term Mixed Chimerism

Haemopoietic stem cell transplantation is a well-established treatment modality for b thalassaemia. The challenge is to minimise graft failure due to the expanded haemopoietic compartment whilst reducing the risk VOD due to the effects of iron load. From 2011 to 2016 thirty-nine consecutive sibling transplants were conditioned with fludarabine 160 mg/m2, treosulfan 42 g/m2, thiotepa 10 mg/kg and ATG (Thymoglobulin) 7.5 mg/kg (FTTA). Endogenous haemopoiesis was suppressed pre-transplantation with hypertransfusions for a minimum of 8 weeks. GvHD prophylaxis was provided with ciclosporin and MMF. The median age was 5 years (2 - 19). The source of stem cells was BM in 33 patients and mixed cord blood and BM in 6 patients. The median cell dose was 3.88 x108 TNC/kg (range 0.23 - 8.51, including patients having red cell depletion for major ABO incompatibility) and 7.19 x 106 CD34+/kg (range 2.05 - 14.43) for the patients receiving bone marrow only; 1.55 x 108 TNC/kg (range 1.27 - 3.9) and 3.32 x 106 CD34+/kg (range 2.06 - 8.79) for BM and 2.47 x 107 TNC/kg (range 0.8 - 7.32) and 0.44 x 106CD34+/kg (range 0.06 - 1.8) for cord blood for the patients receiving a combination of cord blood and bone marrow. The median survival was 25.8 months (2.6-65.9). Patients were Pesaro class I or II (Pesaro class III patients were intensively chelated pre-transplantation to reduce the stage of fibrosis and return to class I or II). All patients were evaluated with liver biopsy pre-transplantation and defibrotide prophylaxis given if Ishak stage ≥3.All patients engrafted and achieved evidence of donor haemopoiesis on day +28, and all but two patients achieved transfusion-independence and donor haematological values. Two patients had secondary graft failure: one patient had progressive reduction of donor haemopoiesis with reestablishment of ineffective thalassaemic haemopoiesis and transfusion dependence on day +313, another patient had reestablishment of ineffective thalassaemic and myelodysplastic clonal haemopoiesis with 7del on day +532; both patients established normal haemopoiesis following a second BMT. There was one death (2.7%), on day +89 due to idiopathic pneumonia syndrome. Acute GvHD ≥ grade 2 occurred in 5 patients (12.8%). Chronic limited GvHD occurred in 6 patients (15.4%) and extensive in 2 patients (5.1%). Chronic GvHD was only present at 18 months in one patient (2.7%). VOD occurred in one patient (2.7%, day +9) and responded to standard measures and defibrotide treatment. The median neutrophil engraftment was 11 days (range 9 to 21). The median platelet engraftment >20 x109/L was 27 days (range 16 to 73) and >50 x109/L was 32 days (range 19 to 73). The median time to cessation of immunosuppression was 160 days (105-309).Chimerism studies on day +28 demonstrated 97.4% in whole blood (WB) and 76.7% in T cells (T) >95%, 2.6% WB and 3.3% T >90-95%, 0% WB and 20% T >50-89%; day +90: 83.8% WB and 57.1% T >95%, 2.7% WB and 14.3% T >90-95%, 10.8% WB and 22.9% T >50-89%, 2.7% WB and 5.7% T <50%; day +180: 50% WB and 44.8% T >95%, 30% WB and 17.2% T >90-95%, 10% WB and 37.9% T >50-89%, 10% WB and 0% T <50%; and day +365: 55.6% WB and 42.3% T >95%, 7.4% WB and 19.2% T >90-95%, 14.8% WB and 18.2% T >50-89%, 22.2% WB and 19.2% T <50%.In conclusion, the 3 years' overall survival was 97.4% and the disease-free survival 90.3%. Following a second procedure for the two cases suffering secondary graft failure, the disease-free survival increased to 97.4%. Hence, FTTA leads to early and sustained engraftment with low rate of graft failure, and minimal occurrence of VOD and IPS, whilst the incidence of GvHD is low, though there is a high rate of mixed chimerism, the large majority which is stable. Further improvements to minimise unstable cases will focus in changes to serotherapy. Disclosuresde la Fuente:bluebird bio: Consultancy; Jazz Pharmaceuticals: Honoraria; HCA: Consultancy.