Immunosuppressive therapy in severe aplastic anemia

Severe aplastic anemia, a disease characterized by pancytopenia and a hypocellular marrow, is treatable by either immunosuppressive therapy (IST) or hematopoietic stem cell transplant. Much is understood about the immune-mediated pathophysiology of AA now, but the inciting factor remains elusive. Many groups around the globe contributed to understanding the disease pathophysiology and optimizing the IST regimen. Horse antithymocyte globulin and cyclosporine, the initial IST regimen, achieved a hematologic response rate in about 60% to 65% of treated patients, with less than 10% achieving a complete count recovery. However, adding a thrombopoietin receptor agonist, eltrombopag (EPAG), to IST improved these response rates to nearly 80% and an unprecedented increase in complete response to almost 40%. The latest report indicates that a high-risk clonal evolution to myeloid malignancies is not increased with hematopoietic stem cell stimulation by adding EPAG in the front line setting. Despite the great success of IST and EPAG in improving early outcomes, relapse remains a problem. Further optimization of upfront therapy and treatment protocol is needed to prevent relapses and decrease clonal evolution rates for even better long-term results.     

Immunosuppressive therapy for adult aplastic anemia in a single institution study

We evaluated the efficacy and long-term outcomes of immunosuppressive therapy (IST) in 50 adult patients with aplastic anemia at a single institution. Twenty-one patients who had not responded to the first course of IST or relapsed after the initial response to IST were retreated with the second course of IST with antithymocyte globulin. The response and relapse rate of the initial IST were 76.7% and 23.3%, respectively. The response rate of salvage IST was 61.9%. Overall survival at 10 years was 84.0%. Failure-free survival at 10 years was 62.0%. Clonal or malignant diseases developed in 2 patients. Early deaths due to bleeding or infection were observed only in elderly patients. We conclude that most patients with aplastic anemia treated with IST show hematologic improvement and excellent long-term survival.     

Immunosuppressive therapy for acquired severe aplastic anemia (SAA): a prospective comparison of four different regimens

OBJECTIVE: This study was designed to investigate four different immunosuppressive therapy (IST) regimens as treatment of acquired severe aplastic anemia (SAA). PATIENTS AND METHODS: 142 consecutive SAA patients were randomized to receive one of the following IST regimens: equine anti-human thymocyte immunoglobulin (E-ATG) alone (IST regimen I); E-ATG and cyclosporine A (CSA) (IST regimen II); E-ATG, CSA plus recombinant human granulocyte-macrophage colony-stimulating factor (rhuGM-CSF) and rhu erythropoietin (rhuEPO) (IST regimen III); or rabbit ATG (ATG-F), CSA, rhuGM-CSF, and rhuEPO (IST regimen IV). No repeated courses of E-ATG or ATG-F were given for nonresponders. All patients also received stanozolol or testosteron propionate. RESULTS: The overall response rate to IST regimen I was 58%. The response to IST regimen II (79%) was significantly higher (p = 0.04), more rapid and complete than after IST regimen I. The response rate to IST regimen IV (53%) was significantly lower than that of IST regimen III (73%, p = 0.039). The additional use of growth factors did not reduce early deaths and did not accelerate hematopoietic recovery after IST. Of the 142 patients enrolled in this trial, 92 (65%) are alive at a median follow-up time of 102 months (range, 54-166 months). The 5-year actuarial survival for IST regimens I, II, III, and IV was 58%, 81%, 80%, and 66%, respectively. CONCLUSION: The combination of E-ATG and CSA remains the best combination for the treatment of SAA patients, producing a survival advantage at 5 years. The addition of growth factors did not improve these results. Rabbit ATG-F appeared less effective than E-ATG.     

免疫抑制疗法与造血干细胞移植治疗成人获得性重型再生障碍性贫血的成本-效果分析

目的分析免疫抑制疗法(IST)与造血干细胞移植(HSCT)治疗成人获得性重型再生障碍性贫血(SAA)的成本-效果。方法通过文献检索获得不同病情状态之间转换的概率,从复旦大学附属华山医院及苏州大学附属第一医院获得SAA患者首次治疗及后续随访花费的中位值。采用卫生经济学的方法建立马尔科夫模型,循环状态模拟运行30年获得相应的增量成本-效果比,比较HSCT和IST治疗不同年龄分组(18~35岁组和35~50岁组)SAA患者的成本-效果。结果18~35岁组患者应用HSCT相对于IST的增量成本效果比(ICER)为14054.19美元/质量调整生命年(QALY),小于意愿支付值(WTP)25397.57美元;而对于35~50岁组患者应用HSCT组相对于IST组的QALY增量为-3.24 QALYs,成本增量为72009.35美元。结论18~35岁获得性SAA患者更推荐选择HSCT,而35~50岁获得性SAA患者更建议选择IST。     

Immunosuppressive therapy with horse anti-thymocyte globulin and cyclosporine as treatment for fulminant aplastic anemia in children

Patients with severe aplastic anemia (SAA) and an absolute neutrophil count (ANC) of 0 typically have fatal outcomes. We defined fulminant AA (FAA) as ANC?=?0 for at least 2 weeks prior to and after immunosuppressive therapy (IST). We analyzed the outcomes of 35 children with FAA among 288 children who enrolled in a prospective study for AA (AA-97 study). AA was classified as FAA (n?=?35), very SAA (vSAA; n?=?129), or SAA (n?=?124). All of the children received the IST with horse anti-thymocyte globulin (ATG) and cyclosporine (CsA). A significantly lower response rate at 6 months was seen in children with FAA when compared to those with vSAA or SAA (40.0, 63.6, and 63.7 %, respectively; p?=?0.027). Of 20 nonresponder patients in the FAA group, 11 were rescued by alternative donor transplantation, and 5 patients showed a late response after 6 months. Consequently, no significant difference was noted in overall survival when comparing the FAA, vSAA, and SAA groups (88.5, 95.8, and 96.8 %). These findings indicate that IST with ATG and CsA is justified as a first-line treatment for children with FAA who lack a human leukocyte antigen-matched sibling donor.     

Improved survival in severe acquired aplastic anemia of childhood

Multi-agent immunosuppressive therapy has produced improved survival for severe acquired aplastic anemia in children. Recently, some investigators have suggested that immunosuppressive therapy may replace bone marrow transplantation as first-line therapy for this disorder. To assess its validity, we compared the outcomes of bone marrow transplantation vs immunosuppressive therapy in one institution from 1987 to 1997. We studied 46 consecutive patients less than 18 years of age who presented between January 1987 and April 1997. Inherited marrow failure syndromes and myelodysplastic syndromes were excluded. Patients received immunosuppressive therapy vs bone marrow transplantation based on availability of HLA-matched donors. The main outcome measures were survival, complete marrow and hematological remission, or partial remission but achieving independence from transfusional support. Twenty patients received multi-agent immunosuppressive therapy (cyclosporine, antithymocyte globulin and methylprednisolone); 11 attained complete remission and three partial remission for a transfusion-independent survival of 70%. Six patients died of infectious and hemorrhagic complications. Twenty-six patients were transplanted and 24 (93%) achieved complete remission; one achieved a PR, 25 remain transfusion independent with a median follow-up of 5.9 years or 70 months. One patient developed AML 34 months after successful transplant and one patient died due to graft failure and complications of transplant. There has been a striking improvement in survival for pediatric patients treated with multi-agent immunosuppression in the last decade. However, transplantation results have also improved and this remains the definitive first-line therapy for severe acquired aplastic anemia in this age group.     

High-dose cyclophosphamide as salvage therapy for severe aplastic anemia

OBJECTIVE: The treatment options for patients with aplastic anemia who do not respond to conventional immunosuppression are limited. The aim of this study was to evaluate high-dose cyclophosphamide in patients with refractory severe aplastic anemia (SAA). MATERIALS AND METHODS: We treated 17 SAA patients with high-dose cyclophosphamide (50 mg/kg/day for 4 consecutive days) who previously did not respond to one or more courses of immunosuppressive therapy. Median age was 31 years (range 6-58); median disease duration was 14 months (range 6-58), and 8 patients met criteria for very severe aplastic anemia (absolute neutrophil count <0.2 x 10(9)/L) at the time of treatment. RESULTS: At median follow-up of 29 months, 10 patients (59%) are alive. Nine patients (53%) achieved a drug-free remission after high-dose cyclophosphamide; 4 patients achieved a complete remission and 5 patients currently meet criteria for a partial remission but continue to improve. One nonresponder to high-dose cyclophosphamide developed paroxysmal nocturnal hemoglobinuria; another nonresponder developed a myelodysplastic syndrome. In responding patients, median time to 500 neutrophils was 54 days (range 35-119), median time to the last platelet transfusion was 99 days (range 51-751), and median time to the last red cell transfusion was 125 days (range 63-796). CONCLUSION: High-dose cyclophosphamide shows promise for salvaging patients with refractory SAA.     

First-line treatment for severe aplastic anemia in children: bone marrow transplantation from a matched family donor versus immunosuppressive therapy

The current treatment approach for severe aplastic anemia in children is based on studies performed in the 1980s, and updated evidence is required. We retrospectively compared the outcomes of children with acquired severe aplastic anemia who received immunosuppressive therapy within prospective trials conducted by the Japanese Childhood Aplastic Anemia Study Group or who underwent bone marrow transplantation from an HLA-matched family donor registered in the Japanese Society for Hematopoietic Cell Transplantation Registry. Between 1992 and 2009, 599 children (younger than 17 years) with severe aplastic anemia received a bone marrow transplant from an HLA-matched family donor (n=213) or immunosuppressive therapy (n=386) as first-line treatment. While the overall survival did not differ between patients treated with immunosuppressive therapy or bone marrow transplantation [88% (95% confidence interval: 86–90) versus 92% (90–94)], failure-free survival was significantly inferior in patients receiving immunosuppressive therapy than in those undergoing bone marrow transplantation [56% (54–59) versus 87% (85–90); P<0.0001]. There was no significant improvement in outcomes over the two time periods (1992–1999 versus 2000–2009). In multivariate analysis, age <10 years was identified as a favorable factor for overall survival (P=0.007), and choice of first-line immunosuppressive therapy was the only unfavorable factor for failure-free survival (P<0.0001). These support the current algorithm for treatment decisions, which recommends bone marrow transplantation when an HLA-matched family donor is available in pediatric severe aplastic anemia.     

Successful lithium carbonate therapy for a patient with intractable and severe aplastic anemia

A 16-year-old female patient who had been given a diagnosis of severe aplastic anemia underwent 2 courses of a combined regimen of corticosteroid pulse therapy and androgen therapy. This proved ineffective. Antilymphocyte globulin therapy was also ineffective. The patient was then given lithium carbonate at a dose of 600 mg/day in combination with an androgen derivative. This had a dramatic effect on her peripheral blood smear. Within 3 weeks after the first course of this treatment, she no longer required red blood cell transfusions. Also, once the lithium carbonate dose was increased to 1,200 mg/day, the patient no longer needed exogenous platelet transfusions. Approximately 6 months after the start of combination therapy, a peripheral blood smear showed entirely normal results. However, 2 months after lithium carbonate was discontinued probably as a result of drug-induced liver dysfunction, both leukocytopenia and thrombocytopenia reappeared. Therefore, lithium carbonate was readministered at a dose of 400 mg/day, and later at a dose of 800 mg/day. Again, the patient showed improvements in 3 blood components without any adverse effects. We concluded that lithium therapy was remarkably useful for this patient with intractable and severe aplastic anemia.     

Cyclosporin therapy for aplastic anemia

We treated 14 patients with aplastic anemia (6 severe, 8 moderate) who did not respond to high dose methylprednisolone, antilymphocyte globulin, or anabolic steroid with cyclosporin (CyA) for more than 4 weeks. Four of them (29%) showed clinical improvement to transfusion-independence. The response rate of patients who received CyA more than 5 weeks was 50% (4 out of 8). The dose of CyA given to the 4 patients who improved after the therapy was 5 to 9 mg/kg/day. One patient needed 11 weeks until the first sign of response (increase of reticulocytes) appeared. In the other three patients, platelets increased first in response to CyA within 5 weeks. Side effects such as hypertricosis and gingival hyperplasia were frequently seen during the CyA therapy, but since they were not so severe or transient, almost all patients tolerated the therapy. These results indicate that CyA can be an efficacious drug for patients with refractory aplastic anemia. Long term treatment with a relatively low dose of CyA may be important for obtaining a high response rate.     

Antithoracic duct lymphocyte globulin therapy of severe aplastic anemia

We performed a prospective randomized trial of antithoracic duct lymphocyte globulin (ATDLG), HLA-haploidentical marrow, and androgen (regimen ABA) versus androgen alone (concurrent STANDARD care controls) in 42 newly diagnosed individuals with severe aplastic anemia. ABA patients also were matched with patients from our preceding study (historical STANDARD care controls). Supportive care and pretreatment patient characteristics were the same in all groups. By life table analysis, 76% of patients receiving ABA are alive at 2 yr compared to 31% of the concurrent control group (p less than 0.002 versus ABA) and 19% of the historical controls (p less than 0.0001 versus ABA) given STANDARD care. ABA patients had greater hematologic improvement than either control group (p less than 0.001). However, improvement with ABA was often incomplete. Toxicity of ATDLG was considerable but manageable. Further studies to determine the mechanism of action and active component(s) of ABA are indicated.     

Post-dengue fever severe aplastic anemia: a rare association

Dengue fever has rarely been reported as an etiology for aplastic anemia. An 8-year-old girl was admitted with fever, myalgia and petechiae. Dengue virus IgM antibodies were positive. She recovered completely, but her thrombocytopenia persisted. Six weeks later she became pancytopenic. A bone marrow aspirate and biopsy showed severe aplastic anemia. She was treated with antithymocytic immunoglobulin, methylprednisolone and cyclosporine. She became transfusion independent 6 months later. Dengue-virus induced aplastic anemia is a rare entity, but it must be identified early for better outcome. Immunosuppressive therapy can induce remission.     

Lymphocytapheresis in a patient with severe aplastic anemia

A 17-year-old Japanese boy with severe aplastic anemia was treated with oxymetholone and prednisolone for 9 weeks without improvement. He then received 2 courses of bolus methylprednisone therapy without improvement and developed a severe liver dysfunction due to this bolus therapy. He had no HLA-compatible sibling for a bone marrow transplantation, and antithymus globulin was not available. A total of 7 lymphocytapheresis treatments were performed, using an IBM 2997 cell separator, over a period of 9 weeks. Hematological and clinical improvement were noted and felt to be related with these lymphocytapheresis treatments, and further therapy was not required. Three years have past since the patient has undergone lymphocytapheresis, and he remains in good health. Thus, lymphocytapheresis may be an alternative therapy for cases of severe aplastic anemia for those patients who have no compatible donor for bone marrow transplantation and when antithymus globulin is not available.     

Bone marrow transplantation for severe aplastic anemia

Allogeneic marrow transplantation from an HLA-identical sibling has proven to be an effective treatment for severe aplastic anemia with restoration of normal hematopoiesis and long-term survival in 70-80% of recipients. Results are related to patient age, with improved survival in younger patients. Marrow transplantation from HLA nonidentical family and unrelated donors has been less successful and is the focus of ongoing clinical research. Graft rejection and graft-versus-host disease (GVHD) remain major problems. A number of pre- and post-transplant immunosuppressive regimens to prevent these complications continue to be studied. The risk of graft rejection is increased in patients who have been transfused before transplant, whereas the risk is decreased with the infusion of larger numbers of transplanted marrow cells. The incidence of graft rejection is 10-32% when cyclophosphamide is used alone as the pretransplant conditioning regimen. The addition of donor buffy coat cells and whole body or limited field radiation have reduced the rate of graft rejection, but increased the incidence of complications such as chronic GVHD and secondary malignancies. GVHD is an immune disorder caused by incompatibility between donor and recipient for histocompatibility antigens. Approximately 18-40% of patients experience moderate to severe acute GVHD. Previous pregnancy in female donors and increasing age of the patient are factors predictive of its development. Methotrexate and cyclosporin have been used most frequently as prophylactic immunosuppressive agents; various combinations of these drugs and prednisone are being evaluated. Symptomatic chronic GVHD occurs in approximately 25% of recipients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Unrelated cord blood transplantation in children with idiopathic severe aplastic anemia

Early results of unrelated cord blood transplantation (UCBT) for severe aplastic anemia (SAA) were poor with a high rate of engraftment failure. This was attributed to the combination of lower graft cell dose and intact host immune system. We performed UCBT in nine children (median age 9 years) with refractory SAA using increasingly immunosuppressive preparative regimens. The time from diagnosis to UCBT was 3.4-20 months (median age 7.2 years), with all children having failed at least one course of immunosuppression. Donor/recipient HLA matching was six of six (n=1), five of six (n=2) and four of six (n=6). The median nucleated cell dose infused was 5.7 x 10(7) cells/kg (range 3.5-20 x 10(7) cells/kg). Six patients were engrafted after the first UCBT. Two of the three patients without hematopoietic reconstitution were engrafted after a second UCBT. All children receiving >or=120 mg/kg of CY in the preparative regimen were engrafted. The median time to myeloid engraftment was 25 (17-59 days) days. Acute GVHD developed in two, and chronic GVHD in five patients. Five patients developed EBV viremia post transplant (lymphoproliferative disorder in three patients). At a median follow-up of 34 months, seven patients are alive and transfusion-independent. UCBT is a feasible treatment strategy for children with refractory SAA lacking a well-matched adult donor.     

Haploidentical donor transplants for severe aplastic anemia

Haploidentical stem cell transplantation (HAPLO) is being increasingly used, and significant progress has been made both with ex vivo T-cell depleted grafts as well as with unmanipulated marrow or peripheral blood grafts. We here review the current status of HAPLO grafts in patients with acquired severe aplastic anemia. Several transplant platforms have been tested, to overcome graft severe rejection and graft vs host disease (GvHD): these include differences in the conditioning regimen, in graft source and graft manipulation, and in GvHD prophylaxis. The latter include ex vivo T-cell depletion and/or antithymocyte globulin and/or high dose post-transplant cyclophosphamide. Some programs also include the use of marrow or cord blood mesenchymal stem cells, infused at the time of transplantation. Extremely encouraging results are being reported especially in the pediatric population, but also in young adults: we will review reports on 375 patients, with an average rejection rate of 6%, grade II-IV GvHD of 23% and 1-year survival of 80%. Finally we will discuss the place of HAPLO transplants in the context of alternative donor grafts for acquired aplastic anemia.     

Alternative donor HSCT for 109 children with acquired severe aplastic anemia:a single center retrospective analysis

正Objective To investigate the efficacy of alternative donor (AD) in the treatment of aplastic anemia (AA) in children.Methods The clinical data of AA children who received AD HSCT in our center from Apr.2010 to Dec.2016 were retrospectively analyzed.The overall survival(OS) rate,implant success rate,incidence of acute and