Management of the refractory aplastic anemia patient: what are the options?

Treatment of relapsed/refractory severe aplastic anemia in children: Evidence-based recommendations

Severe aplastic anemia (SAA) is a rare potentially fatal hematologic disorder. Although overall outcomes with treatment are excellent, there are variations in management approach, including differences in treatment between adult and pediatric patients. Certain aspects of treatment are under active investigation in clinical trials. Because of the rarity of the disease, some pediatric hematologists may have relatively limited experience with the complex management of SAA. The following recommendations reflect an up-to-date evidence-based approach to the treatment of children with relapsed or refractory SAA.

Romiplostim for Treatment of Children and Young Adults With Severe Aplastic Anemia and Myelodysplastic Syndrome

Thrombopoietin receptor agonists (TPO-RAs) induce trilineage hematopoiesis under conditions with acquired hematopoietic failure. We evaluated safety, tolerability, and preliminary efficacy of a TPO-RA, romiplostim (Nplate), with or without standard-of-care immunosuppressive therapy (±IST) for children (ages < 21 y) with newly diagnosed and relapsed/refractory severe aplastic anemia (SAA) and myelodysplastic syndrome (MDS). Data were collected from an observational study and a single arm interventional pilot study. The safety outcome was treatment-related adverse events (AEs). Efficacy was evaluated by complete hematopoietic response (CHR) at week 24. Romiplostim was commenced at 5 µg/kg/week, with dose escalation of 2.5 µg/kg/week (maximum, 20 µg/kg/dose) based on platelet response. Romiplostim was continued until CHR was observed. Ten subjects (SAA, 9 [IST, 4; without IST, 5]; MDS, 1) completed the study (median age: 9.2 y). Median romiplostim dose was 10 µg/kg/week (range: 5 to 17.5 µg/kg/week). The cumulative incidence of CHR was 70.4% (95% CI, 20.2%-92.6%). Among 21 AEs (Grade 1 to 3), 3 were attributed to romiplostim. At a median posttherapy follow-up of 10.9 months (range: 0.7 to 77.5), no clonal evolution, bone marrow fibrosis or mortality was reported. This proof-of-concept study provides data about short-term safety, tolerability, and preliminary efficacy of romiplostim (±IST) for treatment of pediatric SAA/MDS.

The state of the art in the treatment of severe aplastic anemia: immunotherapy and hematopoietic cell transplantation in children and adults

Acquired aplastic anemia (AA) is an immune-mediated bone marrow (BM) failure where marrow disruption is driven by a cytotoxic T-cell-mediated autoimmune attack against hematopoietic stem cells. The key diagnostic challenge in children, but also in adults, is to exclude the possible underlying congenital condition and myelodysplasia. The choice of treatment options, either allogeneic hematopoietic cell transplantation (alloHCT) or immunosuppressive therapy (IST), depends on the patient's age, comorbidities, and access to a suitable donor and effective therapeutic agents. Since 2022, horse antithymocyte globulin (hATG) has been available again in Europe and is recommended for IST as a more effective option than rabbit ATG. Therefore, an update on immunosuppressive strategies is warranted. Despite an improved response to the new immunosuppression protocols with hATG and eltrombopag, some patients are not cured or remain at risk of aplasia relapse or clonal evolution and require postponed alloHCT. The transplantation field has evolved, becoming safer and more accessible. Upfront alloHCT from unrelated donors is becoming a tempting option. With the use of posttransplant cyclophosphamide, haploidentical HCT offers promising outcomes also in AA. In this paper, we present the state of the art in the management of severe AA for pediatric and adult patients based on the available guidelines and recently published studies.

Guidelines for the diagnosis and management of adult aplastic anaemia: A British Society for Haematology Guideline

Pancytopenia with hypocellular bone marrow is the hallmark of aplastic anaemia (AA) and the diagnosis is confirmed after careful evaluation, following exclusion of alternate diagnosis including hypoplastic myelodysplastic syndromes. Emerging use of molecular cyto-genomics is helpful in delineating immune mediated AA from inherited bone marrow failures (IBMF). Camitta criteria is used to assess disease severity, which along with age and availability of human leucocyte antigen compatible donor are determinants for therapeutic decisions. Supportive care with blood and platelet transfusion support, along with anti-microbial prophylaxis and prompt management of opportunistic infections remain key throughout the disease course. The standard first-line treatment for newly diagnosed acquired severe/very severe AA patients is horse anti-thymocyte globulin and ciclosporin-based immunosuppressive therapy (IST) with eltrombopag or allogeneic haemopoietic stem cell transplant (HSCT) from a matched sibling donor. Unrelated donor HSCT in adults should be considered after lack of response to IST, and up front for young adults with severe infections and a readily available matched unrelated donor. Management of IBMF, AA in pregnancy and in elderly require special attention. In view of the rarity of AA and complexity of management, appropriate discussion in multidisciplinary meetings and involvement of expert centres is strongly recommended to improve patient outcomes.

Comparable outcomes with low-dose and standard-dose horse anti-thymocyte globulin in the treatment of severe aplastic anemia

BACKGROUND

The standard dose (SD) of horse anti-thymocyte globulin (hATG) ATGAM (Pfizer, USA) or its biosimilar thymogam (Bharat Serum, India) for the treatment of Aplastic Anemia (AA) is 40 mg/kg/day for 4 days in combination with cyclosporine. Data on the impact of hATG dose on long-term outcomes are limited. Here, we describe our comparative experience using 25 mg/kg/day (low-dose [LD]) hATG for 4 days with SD for the treatment of AA.

METHODS

We retrospectively studied patients with AA (age > 12 years) who received two doses of hATG combined with cyclosporine. Among 93 AA patients who received hATG, 62 (66.7%) and 31 (33.3%) patients received LD and SD hATG with cyclosporine, respectively. Among these,seventeen(18.2%) patients also received eltrombopag with hATG and cyclosporine. Overall response rates [complete response (CR) and partial response (PR)] of LD and SD hATG groups at 3 months (50% vs. 48.4%; p = 0.88), 6 months (63.8% vs. 71.4%; p = 0.67), and 12 months (69.6% vs. 79.2%; p = 0.167) were comparable. The mean (Standard Deviation) 5-year Kaplan-Meier estimate of overall survival and event-free survival was 82.1 (4.6)% and 70.9 (5.5)% for the study population. The mean (standard deviation) 5-year Kaplan-Meier estimate of overall survival and event-free survival of those who received LD hATG versus SD hATG dose was 82.9 (5·3)% versus 74.8 (10·3)% (P = 0·439), and 75.2 (6.2)% versus 61.4(11.2)% (P = 0·441).

CONCLUSION

Our study revealed that the response rates of patients with AA and LD were similar to those of patients with SD to hATG combined with cyclosporine in a real-world setting.

Eltrombopag Preserves the Clonogenic Potential of Hematopoietic Stem Cells During Treatment With Antithymocyte Globulin in Patients With Aplastic Anemia

Aplastic anemia (AA) is frequently caused by a T-cell mediated autoimmune depletion of the hematopoietic stem and progenitor cell (HSPC) compartment. Immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and cyclosporine represents the first-line treatment of AA. One side effect of ATG therapy is the release of proinflammatory cytokines such as interferon-gamma (IFN-γ), which is considered a major factor in the pathogenic autoimmune depletion of HSPC. Recently, eltrombopag (EPAG) was introduced for therapy of refractory AA patients due to its ability to bypass IFN-γ-mediated HSPC inhibition among other mechanisms. Clinical trials have evidenced that EPAG started simultaneously with IST leads to a higher response rate compared with its later administration schedules. We hypothesize that EPAG might protect HSPC from negative effects of ATG-induced release of cytokines. We observed a significant decrease in colony numbers when both healthy peripheral blood (PB) CD34⁺ cells and AA-derived bone marrow cells were cultured in the presence of serum from patients under ATG treatment, as compared with before treatment. Consistent with our hypothesis, this effect could be rescued by adding EPAG in vitro to both healthy and AA-derived cells. By employing an IFN-γ neutralizing antibody, we also demonstrated that the deleterious early ATG effects on the healthy PB CD34⁺ compartment were mediated at least partially by IFN-γ. Hence, we provide evidence for the hitherto unexplained clinical observation that concomitant use of EPAG in addition to IST comprising ATG leads to improved response in patients with AA.

[Metagenomic next-generation sequencing of plasma for the identification of bloodstream infectious pathogens in severe aplastic anemia]

Objective: To analyze the diagnostic value of cell-free plasma metagenomic next-generation sequencing (mNGS) pathogen identification for severe aplastic anemia (SAA) bloodstream infection. Methods: From February 2021 to February 2022, mNGS and conventional detection methods (blood culture, etc.) were used to detect 33 samples from 29 consecutive AA patients admitted to the Anemia Diagnosis and Treatment Center of the Hematology Hospital of the Chinese Academy of Medical Sciences to assess the diagnostic consistency of mNGS and conventional detection, as well as the impact on clinical treatment benefits and clinical accuracy. Results: ①Among the 33 samples evaluated by mNGS and conventional detection methods, 25 cases (75.76%) carried potential pathogenic microorganisms. A total of 72 pathogenic microorganisms were identified from all cases, of which 65 (90.28%) were detected only by mNGS. ②All 33 cases were evaluated for diagnostic consistency, of which 2 cases (6.06%) were Composite, 18 cases (54.55%) were mNGS only, 2 cases (6.06%) were Conventional method only, 1 case (3.03%) was both common compliances (mNGS/Conventional testing) , and 10 cases (30.3%) were completely non-conforming (None) . ③All 33 cases were evaluated for clinical treatment benefit. Among them, 8 cases (24.24%) received Initiation of targeted treatment, 1 case (3.03%) received Treatment de-escalation, 13 cases (39.39%) received Confirmation, and the remaining 11 cases (33.33%) received No clinical benefit. ④ The sensitivity of 80.77%, specificity of 70.00%, positive predictive value of 63.64%, negative predictive value of 84.85%, positive likelihood ratio of 2.692, and negative likelihood ratio of 0.275 distinguished mNGS from conventional detection methods (21/12 vs 5/28, P<0.001) . Conclusion: mNGS can not only contribute to accurately diagnosing bloodstream infection in patients with aplastic anemia, but can also help to guide accurate anti-infection treatment, and the clinical accuracy is high.

Haploidentical bone marrow transplantation in patients with relapsed or refractory severe aplastic anaemia in the USA (BMT CTN 1502): a multicentre, single-arm, phase 2 trial

BACKGROUND

Relapsed severe aplastic anaemia is a marrow failure disorder with high morbidity and mortality. It is often treated with bone marrow transplantation at relapse post-immunosuppressive therapy, but under-represented minorities often cannot find a suitably matched donor. This study aimed to understand the 1-year overall survival in patients with relapsed or refractory severe aplastic anaemia after haploidentical bone marrow transplantation.

METHODS

We report the outcomes of BMT CTN 1502, a single-arm, phase 2 clinical trial done at academic bone marrow transplantation centres in the USA. Included patients were children and adults (75 years or younger) with severe aplastic anaemia that was refractory (fulfilment of severe aplastic anaemia disease criteria at least 3 months after initial immunosuppressive therapy) or relapsed (initial improvement of cytopenias after first-line immunosuppressive therapy but then a later return to fulfilment of severe aplastic anaemia disease criteria), adequate performance status (Eastern Cooperative Oncology Group score 0 or 1, Karnofsky or Lansky score ≥60%), and the presence of an eligible related haploidentical donor. The regimen used reduced-intensity conditioning (rabbit anti-thymocyte globulin 4·5 mg/kg in total, cyclophosphamide 14·5 mg/kg daily for 2 days, fludarabine 30 mg/m2 daily for 5 days, total body irradiation 200 cGy in a single fraction), related HLA-haploidentical donors, and post-transplantation cyclophosphamide-based graft-versus-host disease (GVHD) prophylaxis. Additionally, for GVHD prophylaxis, mycophenolate mofetil was given orally at a dose of 15 mg/kg three times a day up to 1 g three times a day (maximum dose 3000 mg per day) from day 5 to day 35, and tacrolimus was given orally or intravenously from day 5 to day 180 as per institutional standards to maintain a serum concentration of 10-15 ng/mL. The primary endpoint was overall survival 1 year after bone marrow transplantation. All patients treated per protocol were analysed. This study is complete and is registered with ClinicalTrials.gov, NCT02918292.

FINDINGS

Between May 1, 2017, and Aug 30, 2020, 32 patients with relapsed or refractory severe aplastic anaemia were enrolled from 14 centres, and 31 underwent bone marrow transplantation. The median age was 24·9 years (IQR 10·4-51·3), and median follow-up was 24·3 months (IQR 12·1-29·2). Of the 31 patients who received a transplant, 19 (61%) were male and 12 (39%) female. 13 (42%) patients were site-reported as non-White, and 19 (61%) were from under-represented racial and ethnic groups; there were four (13%) patients who were Asian, seven (23%) Black, one (3%) Hawaiian/Pacific Islander, and one (3%) more than one race, with seven (23%) patients reporting Hispanic ethnicity. 24 (77%) of 31 patients were alive with engraftment at 1 year, and one (3%) patient alive with autologous recovery. The 1-year overall survival was 81% (95% CI 62-91). The most common grade 3-5 adverse events (seen in seven or more patients) included seven (23%) patients with abnormal liver tests, 15 (48%) patients with cardiovascular changes (including sinus tachycardia, heart failure, pericarditis), ten (32%) patients with gastrointestinal issues, seven (23%) patients with nutritional disorders, and eight (26%) patients with respiratory disorders. Six (19%) deaths, due to disease and unsuccessful bone marrow transplantation, were reported after transplantation.

INTERPRETATION

Haploidentical bone marrow transplantation using this approach results in excellent overall survival with minimal GVHD in patients who have not responded to immunosuppressive therapy, and can expand access to bone marrow transplantation across all populations. In clinical practice, this could now be considered a standard approach for salvage treatment of severe aplastic anaemia. Attention to obtaining high cell doses (>2·5 × 108 nucleated marrow cells per kg of recipient ideal bodyweight) from bone marrow harvests is crucial to the success of this approach.

FUNDING

US National Heart, Lung, and Blood Institute and US National Cancer Institute.

Hypoplastic myelodysplastic syndrome and acquired aplastic anemia: Immune‑mediated bone marrow failure syndromes (Review)

Hypoplastic myelodysplastic syndrome (hMDS) and aplastic anemia (AA) are rare hematopoietic disorders characterized by pancytopenia with hypoplastic bone marrow (BM). hMDS and idiopathic AA share overlapping clinicopathological features, making a diagnosis very difficult. The differential diagnosis is mainly based on the presence of dysgranulopoiesis, dysmegakaryocytopoiesis, an increased percentage of blasts, and abnormal karyotype, all favouring the diagnosis of hMDS. An accurate diagnosis has important clinical implications, as the prognosis and treatment can be quite different for these diseases. Patients with hMDS have a greater risk of neoplastic progression, a shorter survival time and a lower response to immunosuppressive therapy compared with patients with AA. There is compelling evidence that these distinct clinical entities share a common pathophysiology based on the damage of hematopoietic stem and progenitor cells (HSPCs) by cytotoxic T cells. Expanded T cells overproduce proinflammatory cytokines (interferon-γ and tumor necrosis factor-α), resulting in decreased proliferation and increased apoptosis of HSPCs. The antigens that trigger this abnormal immune response are not known, but potential candidates have been suggested, including Wilms tumor protein 1 and human leukocyte antigen class I molecules. Our understanding of the molecular pathogenesis of these BM failure syndromes has been improved by next-generation sequencing, which has enabled the identification of a large spectrum of mutations. It has also brought new challenges, such as the interpretation of variants of uncertain significance and clonal hematopoiesis of indeterminate potential. The present review discusses the main clinicopathological differences between hMDS and acquired AA, focuses on the molecular background and highlights the importance of molecular testing.

Hereditary Hemochromatosis Associated With Idiopathic Refractory Aplastic Anemia in a Five-Year-Old Boy: A Case Report

Hereditary hemochromatosis (HH) is a multisystem disease characterized by iron overload and various clinical presentations, including cirrhosis, diabetes mellitus, and heart failure. HH can be caused by the human homeostatic iron regulator (HFE) and non-HFE gene mutations. Aplastic anemia is a rare, life-threatening bone marrow failure in which fat replaces pluripotent stem cells, resulting in pancytopenia and hypoplasia of bone marrow. We present a case of a five-year-old-boy who initially presented with a large ecchymosis located at the right side of the chest and abdomen. These started suddenly after minor trauma. Later, he was diagnosed with idiopathic aplastic anemia and treated with immunosuppressive therapy (IST). As part of the workup for pancytopenia, we ordered whole exome sequencing (WES) and diagnosed the patient with autosomal recessive hereditary hemochromatosis (ARHH). The ARHH is caused by HFE pathogenic gene mutation variant (c.187C>G p homozygous genotype). After six months of IST, he still had persistent disease. Human leukocyte antigen (HLA) typing showed he has a sister who is a full match but also has ARHH. Because of this, a haploidentical hematopoietic stem cell transplantation (hHSCT) from the father was performed. The hHSCT had a successful outcome. We suggest that in children with idiopathic aplastic anemia, physicians should be aware of the possibility of co-existing hereditary hemochromatosis or secondary hemochromatosis. Serum ferritin and transferrin saturation should also be measured regularly in order to detect early hemochromatosis.

Haploidentical BMT for severe aplastic anemia with intensive GVHD prophylaxis including posttransplant cyclophosphamide

Severe aplastic anemia (SAA) is a stem cell disorder often treated with bone marrow transplantation (BMT) to reconstitute hematopoiesis. Outcomes of related HLA-haploidentical (haplo) donors after reduced-intensity conditioning with intensive graft-versus-host disease (GVHD) prophylaxis including posttransplantation cyclophosphamide are presented here from 37 SAA, 20 relapsed/refractory (R/R), and 17 treatment-naïve (TN) SAA patients. Median follow-up is 32 months (90% confidence interval [CI], 29-44). The median age was 25 (range, 4-69) years. The median time to neutrophil recovery was 17 days (range, 15-88). Four of 37 patients (11%) experienced graft failure (GF). There was 1 primary GF of 20 patients in the R/R group and 3 of 17 in the TN group at 200 cGy (1 primary, 2 secondary), but none in the 10 patients who received 400 cGy total body irradiation. Two patients with GF succumbed to infection and 2 were rescued with second haplo BMT. The overall survival for all patients is 94% (90% CI, 88-100) at 1 and 2 years. The cumulative incidence of grade II-IV acute GVHD at day 100 is 11%. The cumulative index of chronic GVHD at 2 years is 8%. Similar results were seen in 10 SAA patients who received the identical nonmyeloablative regimen with posttransplant cyclophosphamide but matched donor transplants. Haplo BMT with posttransplant cyclophosphamide represents a potential cure in SAA, with all 20 R/R currently alive, disease-free, and with no evidence of active GVHD. Extending this approach to TN patients was associated with higher GF rates, but an increase in total body irradiation dose to 400 cGy was associated with durable engraftment without greater early toxicity. Nonmyeloablative haplo BMT in TN SAA could lead to a paradigm shift, such that essentially all patients can proceed quickly to safe, curative BMT. These trials were registered at www.cincialtrials.gov as #NCT02224872) and #NCT02833805.

Risk factors associated with poor response to immunosuppressive therapy in acquired aplastic anemia: A meta-analysis of retrospective studies

Acquired aplastic anemia (AA) is a rare hematological disease characterized by bone marrow hypocellularity and varying degrees of pancytopenia. Immunosuppressive therapy (IST) is currently one of the first-line treatments for AA; however, unresponsiveness remains a major concern. Although previous studies have suggested several common risk factors for unresponsiveness, there are currently no widely accepted predictors. Therefore, a meta-analysis of clinical trials including information on factors associated with unresponsiveness of AA to IST was performed in the present study. The PubMed, Embase and Cochrane Library databases were searched for clinical studies on AA evaluating the association between risk factors and unresponsiveness to IST. After the factors were defined from the selected studies, the association between these factors and unresponsiveness to IST was analyzed using Review Manager software. A total of 10 studies comprising 1,820 cases were included in the present meta-analysis. The following factors were identified as predictors of unresponsiveness: Age (≥60 years), sex, absolute neutrophil count, severity of the disease, paroxysmal nocturnal hemoglobinuria clone, human leukocyte antigen (HLA)-DR2 and cytogenetic abnormalities (CAs). Among these factors, only age (≥60 years) [odds ratio (OR)=1.65], HLA-DR2 negativity (OR=2.72) and CAs (OR=1.93) exhibited a statistically significant association with unresponsiveness to IST (P=0.006, P=0.04 and P=0.01, respectively). In conclusion, the present meta-analysis revealed that age ≥60 years, HLA-DR2 negativity and CAs are risk factors for unresponsiveness to IST. This result may enable clinicians to select an effective therapeutic scheme for patients with AA and even provide novel clues to the pathogenesis of AA.

Pathogenesis of aplastic anemia

Aplastic anemia (AA) is a rare and life-threatening bone marrow failure (BMF) that results in peripheral blood cytopenia and reduced bone marrow hematopoietic cell proliferation. The symptoms are similar to myelofibrosis, myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) making diagnosis of AA complicated. The pathogenesis of AA is complex and its mechanism needs to be deciphered on an individualized basis. This review summarizes several contributions made in trying to understand AA pathogenesis in recent years which may be helpful for the development of personalized therapies for AA.

Idiopathic Aplastic Anemia in Children and Adults: Diagnosis, Treatments, and Management - A Review

Aplastic Anemia (AA) is also known as idiopathic aplastic anemia (IAA) and the production of new blood cells ceases in AA, which leads to an abnormal hematological syndrome such as pancytopenia and suppression of hypo-cellular bone marrow. The pathophysiology of AA in most cases is immune-mediated and is stimulated by type 1 cytotoxic T cells. Reliable early diagnostic tests of IAA are not yet available, therefore most of the cases are identified in advanced stages. Recently, abnormal immune response and hematopoietic cell deficiencies are defined genetically, such as in target cells of telomere repair gene mutations and by the dysregulation of T-cell activation pathways. Importantly, anti-thymocyte globulins and cyclosporine-associated immunosuppression are successful treatments for restoring blood cell production in most of the cases, however, clonal hematologic diseases remain challenging. In the current review, we have discussed the common practices in the treatment, pathophysiology, diagnosis, and management of AA.

Hematologic recovery induced by eltrombopag in Japanese patients with aplastic anemia refractory or intolerant to immunosuppressive therapy

Eltrombopag, an oral thrombopoietin-receptor agonist, stimulates hematopoiesis in patients with acquired aplastic anemia (AA) and has higher exposure in patients of East Asian origin. We evaluated the pharmacokinetics, efficacy, and safety of eltrombopag in Japanese patients with AA refractory or intolerant to immunosuppressive therapy (IST). Twenty-one patients (15 with non-severe AA, six with severe AA) with platelet counts < 30,000/µL received eltrombopag in a dose-escalation fashion (25, 50, 75, or 100 mg once daily) depending on individual platelet responses; the responders continued eltrombopag treatment beyond 6 months. The primary endpoint was hematologic response at 6 months, defined as improvements in blood counts or transfusion requirements. Ten (48%) patients achieved hematologic responses in at least one lineage at 6 months. Six patients achieved tri- and/or bi-lineage responses with continuation of eltrombopag treatment, with two patients no longer requiring eltrombopag treatment. The most common adverse events were nasopharyngitis and abnormal hepatic function, with the majority being grade 1 or 2. Cytogenetic abnormalities were observed in three patients; however, no progression to myelodysplastic syndrome/other malignancy was observed. Eltrombopag can safely restore multi-lineage hematopoiesis in Japanese patients with AA refractory or intolerant to IST.Clinical Trial registration NCT02148133.

Immunosuppressive therapy (IST) in adult patients with acquired aplastic anemia (AA): A single-center experience over the past 15 years

OBJECTIVE

Immunosuppressive therapy (IST) with horse anti-thymocyte globulin (hATG) and cyclosporine (CsA) is considered one of the first-line therapies in patients (pts) with acquired aplastic anemia (AA).

METHODS

In our single-center, retrospective analysis response rates (RRs) to ATG/CsA at a minimum of 6 mo were evaluated in 67 treatment-naïve (TN) AA pts (52.2% (35/67) females; median age 45 y (range 18-89 y)) being treated at the West German Cancer Center at the Department of Hematology at the University Hospital of Essen between April 2000 and December 2015.

RESULTS

Overall 6 mo RRs in TN pts following ATG/CsA were 67.2% (45/67) (5-year OS: 79.5%). In TN hATG-treated pts 6 mo RRs were 75.5% (37/49) (5-year OS: 81%) compared to 44.4% (8/18) (5-year OS 73.5%) following rabbit ATG (rATG). Response to ATG/CsA was dependent of age, absolute reticulocyte count (ARC), and disease severity. Six mo RRs to salvage ATG/CsA in relapsed/refractory (R/R) pts were 37.5% (6/16).

CONCLUSION

Our data independently confirm the findings of previous studies that hATG/CsA is superior to rATG/CsA in TN pts. The lack of hATG availability should not result in abstaining it from an indicated ATG therapy, even though ATGAM^® is not registered in Germany.

Design and development of a disease-specific quality of life tool for patients with aplastic anaemia and/or paroxysmal nocturnal haemoglobinuria (QLQ-AA/PNH)-a report on phase III

To date, instruments to measure quality of life (QoL) specifically for patients with acquired aplastic anaemia (AA) and paroxysmal nocturnal haemoglobinuria (PNH) are lacking altogether. As a consequence, this issue is either underevaluated or alternatively, instruments originally designed for cancer patients are being used. We therefore started to systematically develop a AA/PNH-specific QoL (QLQ-AA/PNH) instrument in these ultra-rare diseases according to European Organisation for Research and Treatment of Cancer (EORTC) guidelines. While phases I and II of the process have previously been published, we now report on the resulting instrument (phase III of this process). As part of the phase III of the evaluation process, we approached patients through physicians, patient support groups, and patient conferences. After participants completed the preliminary questionnaire and reported socio-demographic data, they were interviewed in person or via phone with a debriefing interview to find out whether the items were relevant, easy to understand, and acceptable to patients and whether there was anything missing in the questionnaire. We hypothesised what items could be combined into a scale and calculated Cronbach’s alpha to define its preliminary internal consistency. After definition of a priori criteria to keep or delete items, a group of six experts met in person, discussed the results, and decided on in- or exclusion. A total of 48 patients were enrolled, 21 of those suffered from AA (44%), 13 from PNH (27%), and 14 from AA/PNH syndrome (29%). The median time to complete the 69 items was 10 min (range 5–20), mean time 11 min. The compliance criterion (> 95% completion) was fulfilled by 57 items. Twenty-three items were mentioned as especially relevant by ≥ 2% of the patients. Cronbach’s alpha of the hypothesised scales ranged from 0.63 (social support) to 0.92 (fear of progression and illness intrusiveness). Finally, 47 items were kept; 16 were deleted, and 5 were changed, while 1 item expanded. This resulted in 54 items in total. As no issues were mentioned to lacking by a minimum of five patients, no items were added to the questionnaire. After completion, the AA/PNH-QoL tool (QLQ-AA/PNH) was translated according to EORTC guidelines into English, French, and Italian. For patients with PNH and AA until now, the standard assessment for QoL was to use the EORTC Quality of Life Questionnaire (QLQ-C30) or the Functional Assessment of Chronic Illness Therapy Fatigue Instrument (FACIT-Fatigue). We herewith present a new instrument aimed to be better tailored to the needs of PNH and AA patients. The anticipated fourth development phase will be performed for psychometric validation; however, we already explored the internal consistency of the hypothesised scales and found the results to be very good. Hence, the new QLQ-AA/PNH with 54 items can be used in trials and clinical studies from now on, according to EORTC strategy even if the scoring algorithm at this point is preliminary and the QLQ-AA/PNH might change slightly after phase IV. This is important, as there are no other disease-specific instruments available for AA/PNH patients right now.

A Mosquito Bite with Devastating Complications in an Immunocompromised Patient

Infectious complications such as invasive aspergillosis or infection with Stenotrophomonas maltophilia (SM) in immunocompromised patients are associated with a high mortality rate. Our report concerns a 40-year-old male newly diagnosed very severe aplastic anemia (vSAA) who in consequence of a mosquito bite was suffering from skin lesion and consecutive soft tissue phlegmon subsequent to the administration of antithymocyte globulin; a full-thickness autologous meshed skin graft successfully performed to cover skin ulcera after allogeneic stem cell transplantation (SCT). This unusual case illustrates the importance of appropriate diagnosis, anti-infective therapy and close interdisciplinary diagnostic algorithms to minimalize side effects and the selection of resistant strains and to improve patients' outcome.

Eltrombopag for Delayed Platelet Recovery and Secondary Thrombocytopenia Following Allogeneic Stem Cell Transplantation in Children

The delay in platelet recovery after hematopoietic stem cell transplantation (HSCT) is closely related to the overall survival rate of transplanted children. The use of platelet-producing agents such as eltrombopag and romiplostim has made great progress in treating diseases such as immune thrombocytopenia and aplastic anemia. However, the use of such drugs in patients with thrombocytopenia after transplantation, especially in children, is rare. This study aimed to report eltrombopag treatment for 3 children with primary platelet engraftment failure and secondary thrombocytopenia after allogeneic HSCT. Of these patients, 2 had platelets stabilized at ≥50×10/L after eltrombopag treatment and subsequent withdrawal of eltrombopag. All 3 patients showed no clear adverse reactions. The results indicated a wide application prospect of eltrombopag treatment in children with thrombocytopenia after allogeneic HSCT.

[Delayed hematologic response to immunosuppressive therapy in severe aplastic anemia]

目的

分析极重型／重型再生障碍性贫血（V/SAA）患者一线免疫抑制治疗（IST）迟发血液学反应特征，探讨难治性V/SAA尽早二次治疗的合理性。

方法

回顾性分析一线接受IST的533例V/SAA患者临床资料，定义IST后6个月内获得血液学反应为应时反应，定义6~12个月获得血液学反应为迟发反应，观察迟发反应的发生率、血液学反应质量及其影响因素。

结果

533例患者中，45例（8.44%）获得迟发反应，占未获得应时反应且继续接受环孢素A治疗患者的29.03%（45/155）。至IST后12个月及随访结束时迟发反应组血液学反应质量均劣于应时反应组（χ²=62.616，P<0.001和χ²= 6.299，P=0.043）。迟发反应组VSAA患者比例高于应时反应组（57.8％对38.3%，P=0.013），外周血网织红细胞（ARC）比例、ARC计数以及ANC更低，多因素分析显示治疗前ARC<10×10⁹/L的患者获得应时反应的机会明显减少[OR=3.641(95% CI 1.1718~7.719），P=0.001]；未发现独立预测IST后6个月无效患者获得迟发血液学反应的因素。6个月未获血液学反应患者5年总生存率为76.50%（95% CI 71.6%~81.4%）、无事件生存率为29.10%（95% CI 25.2%~33.0%），均显著低于应时反应组患者的97.6%（95% CI 96.6%~98.6%）、84.0%（95% CI 81.1%~86.9%）（P值均<0.001）。

结论

V/SAA患者IST获得迟发血液学反应难以预测，比例较小，疗效质量相对较差。难治性V/SAA患者尽早进行挽救治疗是合理的。

Aplastic anemia: Etiology, molecular pathogenesis, and emerging concepts

Aplastic anemia (AA) is rare disorder of bone marrow failure which if severe and not appropriately treated is highly fatal. AA is characterized by morphologic marrow features, namely hypocellularity, and resultant peripheral cytopenias. The molecular pathogenesis of AA is not fully understood, and a uniform process may not be the culprit across all cases. An antigen-driven and likely autoimmune dysregulated T-cell homeostasis is implicated in the hematopoietic stem cell injury which ultimately founds the pathologic features of the disease. Defective telomerase function and repair may also play a role in some cases as evidenced by recurring mutations in related telomerase complex genes such as TERT and TERC. In addition, recurring mutations in BCOR/BCORL, PIGA, DNMT3A, and ASXL1 as well as cytogenetic abnormalities, namely monosomy 7, trisomy 8, and uniparental disomy of the 6p arm seem to be intimately related to AA pathogenesis. The increased incidence of late clonal disease has also provided clues to accurately describe plausible predispositions to the development of AA. The emergence of newer genomic sequencing and other techniques is incrementally improving the understanding of the pathogenic mechanisms of AA, the detection of the disease, and ultimately offers the potential to improve patient outcomes. In this comprehensive review, we discuss the current understanding of the immunobiology, molecular pathogenesis, and future directions of such for AA.

Upfront eltrombopag monotherapy induces stable hematologic remission in pediatric patients with nonsevere idiopathic aplastic anemia

Aplastic anemia (AA) is characterized by multilineage cytopenias and bone marrow hypocellularity. Severe AA can be treated with immunosuppressive therapy (IST) and/or allogeneic hematopoietic stem cell transplantation. The thrombopoietin agonist eltrombopag has been shown to induce hematopoietic recovery and transfusion independence in adults with refractory and relapsed AA. Recently, upfront eltrombopag therapy in patients with AA in combination with IST has shown efficacy. Data for its use without concurrent IST in pediatric patients with AA remain sparse. Here we report two pediatric patients with AA not meeting severe criteria who achieved hematologic response with upfront eltrombopag monotherapy.

Value of transfusion independence in severe aplastic anemia from patients' perspectives - a discrete choice experiment

Background

Aplastic anemia is a rare, serious blood disorder due to bone marrow failure to produce blood cells. Transfusions are used to reduce risk of bleeding, infection and relieve anemia symptoms. In severe patients, transfusions may be required more than once/week. It is unclear from the patient perspective the impact that transfusions have on quality of life. This study aimed to elicit patient preferences for attributes associated with severe aplastic anemia (SAA) treatment, including transfusion independence.

Methods

An online discrete choice experiment (DCE) was conducted among patients with SAA who experienced insufficient response to immunosuppressive therapy and transfusion dependence for ≥3 months in the past 2 years. Recruitment occurred through the Aplastic Anemia and Myelodysplastic Syndromes International Foundation and referrals from clinical sites in the US and France. Respondents chose between hypothetical treatment pairs characterized by a common set of attributes: transfusions frequency, fatigue, risk of infection, and risk of serious bleeding. Conditional logit model with effects coding was used to estimate part-worth utilities for different attribute levels and the relative importance of each attribute. Predicted utility scores for transfusion frequency levels were reported.

Results

Thirty patients completed the survey. Most were age ≥ 40 years (73.3%), female (70.0%), and from the US (86.7%). 33.3% underwent bone marrow transplant; 36.7% received iron chelation therapy. Patients largely agreed that transfusion independence would result in less burden on time and costs, greater control and quality of life, less fatigue (86.7% noted each) and less scheduling around medical appointments (83.3%). The DCE found highest relative importance for risk of bleeding (0.30), followed by risk of infection (0.28), fatigue (0.23), and frequency of transfusions (0.20). More frequent transfusions resulted in lower utility, particularly when increasing monthly transfusions frequency from 4 (0.57) to 8 (0.35).

Conclusions

Our study showed that higher utility was associated with fewer transfusions in SAA patients with insufficient response to immunosuppressive therapy. While risk of bleeding, risk of infection, and fatigue were more important for patient treatment preferences, frequency of transfusions was also important.

Optimal donor for severe aplastic anemia patient requiring allogeneic hematopoietic stem cell transplantation: A large-sample study from China

HLA-haploidentical hematopoietic stem cell transplantation (HSCT) may be an option for severe aplastic anemia (SAA) patients. However, to date, no large-sample studies have been performed to determine which types of SAA patients are suitable for HLA-haploidentical HSCT. We retrospectively studied 189 consecutive patients with SAA who underwent HLA-identical or HLA-haploidentical HSCT at seven transplant centers in China. Propensity score matching (PSM) was applied in this study to reduce the influence of potential confounders. The 5-year overall survival (OS) rate was 72.0% in the HLA-haploidentical group and 76.5% in the HLA-identical group. The median time to achieve engraftment and the incidence of acute GVHD/chronic GVHD were not significantly different between the two groups. In the subgroup analysis, the outcome of patients older than 40 years in the HLA-haploidentical group was significantly poorer than that of patients younger than 40 years in the same group and that of patients older than 40 years in the HLA-identical group. Based on the above results, we suggest that HLA-haploidentical relative HSCT should be considered as a valid alternative option for patients younger than 40 years with SAA for whom no matched sibling donor is available.

First-line choice for severe aplastic anemia in children: Transplantation from a haploidentical donor vs immunosuppressive therapy

We retrospectively compared the outcomes of children with severe aplastic anemia (SAA) who received immunosuppressive therapy (IST) or who underwent hematopoietic stem cell transplantation (HSCT) from a haploidentical donor (HID), between 2007 and 2016. A total of 52 children with SAA under the age of 17 years were initially treated with IST (n = 24) or haploidentical HSCT (n = 28) as first-line treatment. The estimated 10-year overall survival was 73.4 ± 12.6% and 89.3 ± 5.8% in patients treated with IST or HID-HSCT (P = .806). The failure-free survival was significantly inferior in patients receiving IST than in those undergoing transplantation from an HID (52.6 ± 10.5% vs 89.3 ± 5.8, P = .008). In univariate and multivariate analysis, the choice of first-line immunosuppressive therapy was the only adverse predictor for failure-free survival. At the last follow-up, completely normal blood count was observed in 11 of 20 (55.0%) and 24 of 25 (96.0%) live cases in IST and HID-HSCT cohort (P = .003). These suggest that HSCT from a haploidentical donor could be considered as first-line treatment in children who lack a matched related donor, especially in experienced transplantation centers.

Role of Arsenic Trioxide in the Management of Aplastic Anemia

Aplastic anemia is a common problem in the developing world with therapeutic challenges as most of the patients are non-affording to standard care owing to resource constraints. We present the results of an open label single arm, non-randomized, single center, prospective phase II trial of the compassionate use of arsenic trioxide in patients refractory to ATG or unable to afford the standard of care therapy. The study was prematurely terminated at eighth week due to non-response in 100% of patients and death in two patients. The results are contradictory to what is already published and needs validation in a multicentric setting.

Nationwide survey on the use of eltrombopag in patients with severe aplastic anemia: a report on behalf of the French Reference Center for Aplastic Anemia

Few therapeutic options are available for patients with aplastic anemia who are ineligible for transplantation or refractory to immunosuppressive therapy. Eltrombopag was recently shown to produce trilineage responses in refractory patients. However, the effects of real-life use of this drug remain unknown. This retrospective study (2012–2016) was conducted by the French Reference Center for Aplastic Anemia on patients with relapsed/refractory aplastic anemia, and patients ineligible for antithymocyte globulin or transplantation, who received eltrombopag for at least 2 months. Forty-six patients with aplastic anemia were given eltrombopag without prior antithymocyte globulin treatment (n=11) or after antithymocyte globulin administration (n=35) in a relapsed/refractory setting. Eltrombopag (median daily dose 150 mg) was introduced 17 months (range, 8–50) after the diagnosis of aplastic anemia. At last followup, 49% were still receiving treatment, 9% had stopped due to a robust response, 2% due to toxicity and 40% due to eltrombopag failure. Before eltrombopag treatment, all patients received regular transfusions. The overall rates of red blood cell and platelet transfusion independence were 7%, 33%, 46% and 46% at 1, 3, 6 months and last follow-up. Responses were slower to develop in antithymocyte treatment-naïve patients. In patients achieving transfusion independence, hemoglobin concentration and platelet counts improved by 3 g/dL (interquartile range, 1.4–4.5) and 42×10⁹/L (interquartile range, 11–100), respectively. Response in at least one lineage (according to National Institutes of Health criteria) was observed in 64% of antithymocyte treatment-naïve and 74% of relapsed/refractory patients, while trilineage improvement was observed in 27% and 34%, respectively. We found high rates of hematologic improvement and transfusion independence in refractory aplastic anemia patients but also in patients ineligible for antithymocyte globulin receiving first-line treatment. In conclusion, elderly patients unfit for antithymocyte globulin therapy may benefit from eltrombopag.

Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells Expanded In Vitro for Treatment of Aplastic Anemia: A Multicenter Phase II Trial

We conducted a phase II, noncomparative, multicenter study to assess the efficacy and safety of allogeneic bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) expanded in vitro for patients with aplastic anemia (AA) refractory to immunosuppressive therapy. Seventy‐four patients from seven centers received allogeneic BM‐MSCs at a dose of 1–2 × 10⁶ cells/kg per week for 4 weeks. Responses were assessed at 0.5, 1, 2, 3, 6, 9, and 12 months after the first cells infusion. Patients with response at 1 month continued to receive four infusions. All patients were evaluable. The overall response rate was 28.4% (95% confidence interval, 19%–40%), with 6.8% complete response and 21.6% partial response. The median times to response of leukocytic, erythrocytic, and megakaryocytic linages were 19 (range, 11–29), 17 (range, 12–25), and 31 (range, 26–84) days, respectively. After median follow‐up of 17 months, overall survival was 87.8%. Seven patients developed transitory and mild headache and fever, but no other adverse events were observed. Antithymocyte globulin used in previous treatment and no activated infection throughout treatment were predictors for response. Allogeneic BM‐MSCs infusion is a feasible and effective treatment option for refractory AA. The trial was registered at www.clinicaltrials.gov as NCT00195624. Stem Cells Translational Medicine2017;6:1569–1575

Unusual Anemias

Many processes lead to anemia. This review covers anemias that are less commonly encountered in the United States. These anemias include hemoglobin defects like thalassemia, bone marrow failure syndromes like aplastic anemia and pure red cell aplasia, and hemolytic processes such as paroxysmal nocturnal hemoglobinuria. The pathogenesis, diagnostic workup, and treatment of these rare anemias are reviewed.

Alternative Donor Transplantation with High-Dose Post-Transplantation Cyclophosphamide for Refractory Severe Aplastic Anemia

Severe aplastic anemia (SAA) is a life-threatening hematopoietic stem cell disorder that is treated with bone marrow transplantation (BMT) or immunosuppressive therapy (IST). The management of patients with refractory SAA after IST is a major challenge. Alternative donor BMT is the best chance for cure in refractory SAA, but morbidity and mortality from graft failure and complications of graft-versus-host disease (GVHD) have limited enthusiasm for this approach. Here, we employed post-transplantation high-dose cyclophosphamide in an effort to safely expand the donor pool in 16 consecutive patients with refractory SAA who did not have a matched sibling donor. Between July 2011 and August 2016, 16 patients underwent allogeneic (allo) BMT for refractory SAA from 13 haploidentical donors and 3 unrelated donors. The nonmyeloablative conditioning regimen consisted of antithymocyte globulin, fludarabine, low-dose cyclophosphamide, and total body irradiation. Post-transplantation cyclophosphamide 50 mg/kg/day i.v. on days +3 and +4 was administered for GVHD prophylaxis. Additionally, patients received mycophenolate mofetil on days +5 through 35 and tacrolimus from day +5 through 1 year. The median age of the patients at the time of transplantation was 30 (range, 11 to 69) years. The median time to neutrophil recovery over 1000 × 103/mm3 for 3 consecutive days was 19 (range, 16 to 27) days, to red cell engraftment was 25 (range, 2 to 58) days, and to last platelet transfusion to keep platelets counts over 50 × 103/mm3 was 27.5 (range, 22 to 108) days. Graft failure, primary or secondary, was not seen in any of the patients. All 16 patients are alive, transfusion independent, and without evidence of clonality. The median follow-up is 21 (range, 3 to 64) months. Two patients had grade 1 or 2 skin-only acute GVHD. These same 2 also had mild chronic GVHD of the skin/mouth requiring systemic steroids. One of these GVHD patients was able to come off all IST by 15 months and the other by 17 months. All other patients stopped IST at 1 year. Nonmyeloablative alloBMT using post-transplantation cyclophosphamide allowed for safe expansion of the donor pool to include HLA-haploidentical donors. This approach appears promising in refractory SAA patients. Importantly, engraftment was 100%, pre-existing clonal disease was eradicated, and the risk of GVHD was low.

From chronic immune thrombocytopenia to severe aplastic anemia: recent insights into the evolution of eltrombopag

Thrombopoietin (TPO) is the most potent cytokine stimulating thrombopoiesis. Therapy with exogenous TPO is limited by the formation of antibodies cross-reacting with endogenous TPO. Mimetics of TPO are compounds with no antigenic similarity to TPO. Eltrombopag is an orally-active nonpeptide small molecule that binds to the transmembrane portion of the TPO receptor MPL. Initial trials of eltrombopag have centered on immune thrombocytopenia (ITP), which is due to both increased destruction and decreased production of platelets. Eltrombopag at 25-75 mg/day has been shown to be highly effective in raising the platelet count in ITP with suboptimal response to immunosuppression and splenectomy. These successful results led to the exploration of eltrombopag in other thrombocytopenic disorders. In hepatitis C viral infection, eltrombopag raises the platelet count sufficiently enough to allow treatment with ribavirin and pegylated interferon. Because MPL is expressed on hematopoietic cells, eltrombopag use in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) might enhance leukemic proliferation. Clinical trials of eltrombopag in MDS and AML, however, have shown amelioration of thrombocytopenia without promoting disease progression. In severe aplastic anemia (SAA) not responding to immunosuppression with anti-thymocyte globulin (ATG) and cyclosporine, eltrombopag as a single agent at 150-300 mg/day results in an overall response rate of 40-70%. At high doses, adverse effects including pigmentation, gastrointestinal upset and hepatic derangement have become evident. Current studies have examined the first-line use of eltrombopag in combination with ATG in SAA. In a recent study, eltrombopag used at 150 mg/day with horse ATG resulted in an overall response rate of 90% in newly diagnosed SAA patients, with a complete response rate of about 50%. Clonal karyotypic aberrations are, however, found in 10-20% of SAA patients treated with eltrombopag. The safety and efficacy of eltrombopag in SAA require further evaluation, particularly when it is used with less intensive immunosuppression.

Nontransplant therapy for bone marrow failure

Nontransplant therapeutic options for acquired and constitutional aplastic anemia have significantly expanded during the last 5 years. In the future, transplant may be required less frequently. That trilineage hematologic responses could be achieved with the single agent eltrombopag in refractory aplastic anemia promotes new interest in growth factors after years of failed trials using other growth factor agents. Preliminary results adding eltrombopag to immunosuppressive therapy are promising, but long-term follow-up data evaluating clonal evolution rates are required before promoting its standard use in treatment-naive disease. Danazol, which is traditionally less preferred for treating cytopenias, is capable of preventing telomere attrition associated with hematologic responses in constitutional bone marrow failure resulting from telomere disease.

Development of a disease-specific quality of life questionnaire for patients with aplastic anemia and/or paroxysmal nocturnal hemoglobinuria (QLQ-AA/PNH)-report on phases I and II

Acquired aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria (PNH) are interrelated ultra-rare diseases. Quality of life (QoL) evaluation tools used in studies for AA and PNH are unspecific and designed for cancer patients (e.g., the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, EORTC QLQ-C30). Given the complexity of AA and PNH, variation in symptoms and treatments, younger age of many patients, and the fact that AA and PNH are not classified as malignant diseases, it is likely that cancer-specific questionnaires are inappropriate. We generate an AA/PNH-specific QoL questionnaire (QLQ-AA/PNH), performed according to EORTC guidelines. QoL issues were obtained from the literature and interviews with patients and physicians (phase I), then ranked by patients and physicians. In phase II, items were created. Patients in more than 25 German and Swiss cities were interviewed face to face. In phase I, interviews of 19 patients and 8 physicians specialized in AA/PNH treatment resulted in 649 QoL issues; these were condensed to 175 and graded according to their importance by 30 patients and 14 physicians (phase II). Five physicians took part in phases I and II. Altogether, 97 issues were rated important. Twelve EORTC QLQ-C30 items were not rated important, while several new QoL aspects were brought up. Modifications in wording and phrasing led to two questionnaires with 77 items regarding general QoL aspects and 20 items regarding medical care. Important QoL aspects of PNH/AA patients are inappropriately captured with available QoL tools. Developing a new QoL questionnaire specific for this patient group is warranted.

A Comparison of Outcomes for Cord Blood Transplantation and Unrelated Bone Marrow Transplantation in Adult Aplastic Anemia

Earlier reports suggested that umbilical cord blood transplantation (UCBT) for aplastic anemia (AA) was feasible in alternative transplantation. To identify differences in outcomes of UCBT and HLA-matched or mismatched unrelated bone marrow transplantation (UBMT) in adults with AA, we analyzed registry data of the Japan Society for Hematopoietic Cell Transplantation and compared results of UCBT (n = 69) to 8/8-matched (n = 101), 7/8-matched (n = 65), or 6/8-matched (n = 37) UBMT. The transplantation period was from 2002 to 2012, and patients 16 years or older with AA were eligible. Median ages were 49, 35, 28, and 30 years for UCBT, 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively. In multivariate analysis, risk of mortality was lower for 8/8-matched UBMT compared with that of UCBT (hazard ratio [HR], .55; 95% confidence interval [CI], .32 to .94; P = .029), adjusted for age and graft-versus-host disease (GVHD) prophylaxis, which were other associated factors. Mortality risks of 7/8-matched UBMT (HR, .55; 95% CI, .29 to 1.02) or 6/8-matched UBMT (HR, .67; 95% CI, .32 to 1.39) were not significantly different from those of UCBT. Risks of grade 3 or 4 acute and chronic GVHD were not different among the 4 groups. The most prevalent cause of death was graft failure in UCBT and 6/8-matched UBMT and infection in 8/8-matched and 7/8-matched UBMT. Under 40 years old,survival of UCBT was similar to that of UBMT (76%, 79%, 83%, and 83% for UCBT and 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively, at 3 years), adjusted for transplantation period, which was another associated factor; however, for ages over 40 years, that of UCBT tended to be lower (47%, 64%, 64%, and 75% for UCBT, 8/8-matched, 7/8-matched, and 6/8-matched UBMT, respectively, at 3 years). To conclude, these data suggest that UCBT could be an alternative treatment option for younger adults when matched sibling or adequate UBMT donors are not available.

Unmanipulated haploidentical haematopoietic stem cell transplantation for children with severe aplastic anaemia

Haploidentical haematopoietic stem cell transplantation (haplo-HSCT) used to be a third-line treatment option for childhood severe aplastic anaemia (SAA). We conducted this retrospective study of 36 children (38 transplants) who received haplo-HSCT from human leucocyte antigen (HLA)-mismatched related donors between July 2002 and November 2013 at five HSCT centres in China, including 17 cases that were 5/6 HLA matched (Group 1) and 21 that were 4/6 or 3/6 HLA matched (Group 2). Although patients in Group 2 had a higher incidence of grade II-IV acute graft-versus-host disease (57·9% vs. 5·9%, P = 0·001), they had similar rates of graft failure (5·3% vs. 5·9%, P = 0·742) and overall survival (80·8% vs. 93·8%, P = 0·234) as Group 1. Unmanipulated haplo-HSCT is an effective treatment for SAA children with satisfactory outcome of this cohort, especially in the 5/6 HLA-matched group. For patients in critical situations, such as unresponsive to immunosuppressive therapy, refractory infection and failing first HSCT, to bring forward the timing of haplo-HSCT is a feasible salvage strategy with better and faster donor accessibility.

Extracorporeal photopheresis in solid organ transplant-associated acute graft-versus-host disease

BACKGROUND

Extracorporeal photopheresis (ECP) culls pathogenic T lymphocytes, be these the clones of cutaneous T-cell lymphoma, or mediators of chronic graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (BMT-GVHD). Whether or not ECP may have an effect in the rarer instances of solid organ transplantation-associated GVHD (SOT-GVHD) is unclear. Mortality rates in SOT-GVHD rival those of transfusion-associated GVHD, with fatalities preceded by pancytopenia and peripheral blood chimerism (PBC) levels exceeding 20%. ECP has been described in two SOT-GVHD cases to date, with one surviving.

STUDY DESIGN AND METHODS

Clinicolaboratory features (including HLA relationships) in a case of multivisceral transplantation were reviewed from the time of surgery to the onset and progression of SOT-GVHD. ECP, which was introduced as a less immunosuppressive and more selective intervention, was assessed for its effect on serial PBC (as measured by short-tandem-repeat analysis) and clinical outcome.

RESULTS

Multivisceral SOT-GVHD manifested with erythroderma, neutropenic sepsis, and PBC increasing from 6% on Posttransplant Day (PTD) 38 to 78% by PTD 60 (at a doubling time of 6 days despite corticosteroids). ECP was administered on PTDs 62 and 67 and was associated with the first evidence of PBC decay to 67% on PTD 69. Death nevertheless ensued on the last day of salvage antithymocyte globulin (PTDs 69-73) despite further PBC reduction to 41%.

CONCLUSION

Further study is needed to determine if the sooner or more frequent application of ECP might attenuate the high case fatality rates of SOT-GVHD.

Second allogeneic stem cell transplant for aplastic anaemia: a retrospective study by the Severe Aplastic Anaemia Working Party of the European Society for Blood and Marrow Transplantation

We analysed the outcome of a second allogeneic haematopoietic stem cell transplant (alloHSCT) in 162 patients reported to the European Society for Blood and Marrow Transplantation between 1998 and 2009. Donor origin was a sibling in 110 and an unrelated donor in 52 transplants, respectively. The stem cell source was bone marrow in 31% and peripheral blood in 69% of transplants. The same donor as for the first alloHSCT was used in 81% of transplants whereas a change in the choice of stem cell source was reported in 56% of patients, mainly from bone marrow to peripheral blood. Neutrophil and platelet engraftment occurred in 85% and 72% of patients, after a median time of 15 and 17 days, respectively. Grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD occurred in 21% and 37% of patients, respectively. Graft failure (GF) occurred in 42 patients (26%). After a median follow-up of 3·5 years, the 5-year overall survival (OS) was 60·7%. In multivariate analysis, the only factor significantly associated with a better outcome was a Karnofsky/Lansky score ≥80 (higher OS). We conclude that a second alloHSCT is feasible rescue option for GF in SAA, with a successful outcome in 60% of cases.

[Aplastic anemia: Current state of diagnosis and treatment]

Aplastic anemia (AAI) is a rare life-threatening disorder which is characterized by bi- or tricytopenia and hypoplastic or aplastic bone marrow. AA can present as an acquired or congenital disorder. In recent years it was noted that a subgroup of patients with seemingly acquired AA with onset in adulthood carry mutations which cause or at least predispose to bone marrow failure, e.g. mutations in the genes of the telomerase complex. Options for first-line treatment are allogeneic stem cell transplantation or immunosuppression. The decision depends on severity of the disease, age and comorbidity of the patient and availability of a matched stem cell donor. Probability of survival after HLA-identical sibling transplantation exceeds 90% in young patients with bone marrow as the stem cell source and conditioning with an ATG-containing regimen. Results of matched unrelated donor transplantation have improved substantially over the last 10 years. Matched unrelated donor transplantation is increasingly considered as the first-line treatment for very young patients who are candidates for transplantation, but lack an HLA-identical sibling donor. The gold standard for immunosuppression is the combination of antithymocyte globulin (ATG) and cyclosporine A (CsA). ATG, a polyvalent antibody preparation, is obtained from animals after immunization with human thymocytes. Response rate and overall survival after horse ATG treatment are significantly higher compared to rabbit ATG. Recent trials reported a surprisingly high rate of bi- and trilinear response to treatment with the thrombopoietin receptor agonist eltrombopag in patients refractory to immunosuppression. Ongoing trials now address the potential role of eltrombopag as an adjunct to immunosuppression in first-line treatment.

Immunosuppressive therapy for transplant-ineligible aplastic anemia patients

Aplastic anemia is a rare life-threatening bone marrow failure that is characterized by bicytopenia or pancytopenia in the peripheral blood and a hypoplastic or aplastic bone marrow. The patients are at risk of infection and hemorrhage due to neutropenia and thrombocytopenia and suffer from symptoms of anemia. The main treatment approaches are allogeneic stem cell transplantation and immunosuppression. Here, we review current standard immunosuppression and the attempts that have been made in the past two decades to improve results: review of recent developments also reveals that sometimes not only the advent of new drugs, good ideas and well-designed clinical trials decide the progress in the field but also marketing considerations of pharmaceutical companies. Aplastic anemia experts unfortunately had to face the situation that efficient drugs were withdrawn simply for marketing considerations. We will discuss the current options and challenges in first-line treatment and management of relapsing and refractory patients with an emphasis on adult patients. Some promising new approaches are currently under investigation in prospective, randomized trials.

Haploidentical BMT and post-transplant Cy for severe aplastic anemia: a multicenter retrospective study

Patients with refractory severe aplastic anemia (SAA) who lack a matched sibling or unrelated donor need new therapeutic approaches. Hematopoietic SCT (HSCT) using mismatched or haploidentical related donors has been used in the past, but was associated with a significant risk of GVHD and mortality. Recently, the use of post-transplant cyclophosphamide (Cy) has been shown to be an effective strategy to prevent GVHD in recipients of haploidentical HSCT, but the majority of reports have focused on patients with hematology malignancies. We describe the outcome of 16 patients who underwent haploidentical transplantation using a reduced-intensity conditioning regimen with post-transplant Cy. Stem cell sources were BM (N=13) or PBSCs (N=3). The rate of neutrophil engraftment was 94% and of platelet engraftment was 75%. Two patients had secondary graft failure and were successfully salvaged with another transplant. Three patients developed acute GVHD being grades 2-4 in two. Five patients have died and the 1-year OS was 67.1% (95% confidence interval: 36.5-86.4%). In our small series, the use of a reduced-intensity conditioning with post-transplant Cy in haploidentical BMT was associated with high rates of engraftment and low risk of GVHD in patients with relapsed/refractory SAA.

Autoimmune and other cytopenias in primary immunodeficiencies: pathomechanisms, novel differential diagnoses, and treatment

Autoimmunity and immune dysregulation may lead to cytopenia and represent key features of many primary immunodeficiencies (PIDs). Especially when cytopenia is the initial symptom of a PID, the order and depth of diagnostic steps have to be performed in accordance with both an immunologic and a hematologic approach and will help exclude disorders such as systemic lupus erythematosus, common variable immunodeficiency, and autoimmune lymphoproliferative syndromes, hemophagocytic disorders, lymphoproliferative diseases, and novel differential diagnoses such as MonoMac syndrome (GATA2 deficiency), CD27 deficiency, lipopolysaccharide-responsive beige-like anchor (LRBA) deficiency, activated PI3KD syndrome (APDS), X-linked immunodeficiency with magnesium defect (MAGT1 deficiency), and others. Immunosuppressive treatment often needs to be initiated urgently, which impedes further relevant immunologic laboratory analyses aimed at defining the underlying PID. Awareness of potentially involved disease spectra ranging from hematologic to rheumatologic and immunologic disorders is crucial for identifying a certain proportion of PID phenotypes and genotypes among descriptive diagnoses such as autoimmune hemolytic anemia, chronic immune thrombocytopenia, Evans syndrome, severe aplastic anemia/refractory cytopenia, and others. A synopsis of pathomechanisms, novel differential diagnoses, and advances in treatment options for cytopenias in PID is provided to facilitate multidisciplinary management and to bridge different approaches.