Effectiveness of immunosuppressive therapy in older patients with aplastic anemia. European Group for Blood and Marrow Transplantation Severe Aplastic Anaemia Working Party

Profile and Predictors of Infection Following Anti-thymocyte Globulin or Anti-lymphocyte Globulin with Cyclosporine in Aplastic Anemia

Immunosuppressive therapy (IST) with anti-thymocyte globulin (ATG) and Cyclosporine (CSA) in aplastic anaemia (AA) results in improvement of blood counts between 3 and 6 months for the majority of patients. Infection is the most lethal complication in aplastic anemia and may arise due to several factors. We performed this study to determine the prevalence and predictors of specific infection types before and after IST. Six hundred and seventy-seven (546 adults; 434 males) transplant ineligible patients received ATG and CSA between 1995 and 2017. All patients who were transplant ineligible and received IST in this period were included. Infections before IST was seen in 209 (30.9%) and in 430 (63.5%) patients post IST. There were 700 infective episodes in the six months post-IST, including 216 bacterial, 78 fungal, 33 viral, and 373 culture-negative febrile episodes. Infections were highest (98, 77.8%) in very severe aplastic anaemia as compared to Severe AA (SAA) and Non-Severe AA (NSAA) (p < 0.001). Infections were also significantly higher in those who did not respond to ATG (71.1% vs. 56.8%, p = 0.003). At six months post-IST were 545 (80.5%) alive, and there were 54 (7.9%) deaths due to infection. Significant predictors of mortality were paediatric AA, very severe aplastic anaemia, pre or post ATG infections, and lack of response to ATG. Mortality was highest in those with combined bacterial and fungal infections post IST (p < 0.001). We conclude that infections are a common complication (63.5%) of IST. Mortality was highest when both bacterial and fungal infections were present. Routine use of growth factors and prophylactic antifungal and antibacterial agents was not part of our protocol, despite which 80.5% of the cohort was alive at the end of six months.

Efficacy of Eltrombopag with Immunosuppressive Therapy Versus Immunosuppressive Therapy Alone on Severe Aplastic Anaemia: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Severe aplastic anaemia (SAA) is a syndrome of bone marrow failure caused by T cell-mediated destruction of haematopoietic stem cells and progenitor cells. Whether patients with SAA should be treated with eltrombopag (EPAG) and immunosuppressive therapy (IST) or IST alone remains debatable. Therefore, we conducted this meta-analysis to compare the efficacy of eltrombopag + IST with that of IST alone in patients with SAA and to assess the difference in the efficacy of eltrombopag in adults and children.

METHODS

We performed this meta-analysis by retrieving studies that met the inclusion and exclusion criteria from PubMed, EMBASE, and the Cochrane Library up to 1 January 2023. We used a random-effects model to calculate odds ratios (ORs) with 95% confidence intervals (CIs) for primary and secondary outcomes. I² statistics were used to evaluate the heterogeneity of the included studies.

RESULTS

Six studies involving a total of 699 patients were included. In terms of the primary outcomes, our pooled results indicated that patients treated with EPAG + IST had a higher 6-month overall response rate (OR = 2.25; 95% CI, 1.60-3.16; p < 0.00001), a higher 6-month complete response rate (OR = 2.61; 95% CI, 1.82-3.74; p < 0.00001), and a lower 6-month nonresponse rate (OR = 0.32; 95% CI, 0.19-0.52; p < 0.00001). However, there was no significant difference in the rate of 6-month partial response (OR = 0.94; 95% CI, 0.49-1.81; p = 0.85).

CONCLUSION

This meta-analysis indicated that patients treated with additional eltrombopag for IST may have a higher rate of haematological response.

Treatment outcome of 301 aplastic anemia patients in China: a 10-year follow-up and real-world data from single institute experience

OBJECTIVE

This study was carried out to explore clinical treatment and prognosis of patients with AA with different economic status. Methods: We retrospectively analyzed the clinical outcome of 301 patients with AA in our center from April 2008 to November 2017.

RESULTS

Treatments included anti-thymocyte globulin (ATG) or anti-lymphocyte globulin (ALG) combined with cyclosporineA (CsA) (9%), allogeneic hematopoietic stem cell transplantation (allo-HSCT) (7%), CsA combined with androgen or CsA alone (hereinafter referred to as CsA group) (77%), no specific therapy (7%). The 5-year overall survival (OS) was higher in patients with non-severe AA (94.6%) compared with those with severe AA (SAA) (66.6%, P <.001), very severe AA (VSAA) (41.3%, P <.001). The 5-year OS was 76.5% in patients with SAA/VSAA treated with ATG/ALG combined with CsA, 75% in allo-HSCT group(P =.936), 63.6% in CsA group (P =.557), which was significantly higher than no specific therapy group (21.8%, P =.002). For those who responded to CsA , the duration of CsA (median follow-up time: 27 months, 1-101 months) was positively correlated with progression-free survival (r=0.603, P <.001). Multivariate analysis revealed that 36-65 years of age, SAA/VSAA, and no specific therapy were independent risk factors for inferior survival.

CONCLUSION

The treatment of elderly patients with AA still faces challenges. CsA is benefit to the survival of SAA/VSAA patients. AA patients, who responded to initialy CsA treatment, may benefit from prolonged CsA treatment. In view of the side effects of CsA, the timing of withdrawal is worth further exploration.

Similar outcomes of alemtuzumab-based hematopoietic cell transplantation for SAA patients older or younger than 50 years

Survival after allogeneic hematopoietic cell transplantation (HSCT) for severe aplastic anemia (SAA) among older patients remains poor and associated with increased risk for graft-versus-host disease (GVHD). In this retrospective study of 65 consecutive patients with acquired SAA who were transplanted using fludarabine, low-dose cyclophosphamide, and alemtuzumab (FCC), outcomes of 27 patients aged at least 50 years were compared with those of 38 patients younger than 50 years. The median age of the older cohort was 61 years (range, 51-71 years); 21 (78%) patients were transplanted from unrelated donors (3 of 21 from HLA 9/10 mismatch donors) and 6 from matched sibling donors. One-year GVHD-free, relapse-free survival (GRFS) was comparable to that of patients younger than 50 years (84% vs 94%, respectively; P = .23). Both groups showed low rates of acute (5% vs 4%) and chronic (18% vs 14%) GVHD, with no cases of severe GVHD among matched donor transplants, and similar 1-year transplant-related mortality (14% vs 5.4%, older vs younger; P = .23). HSCT comorbidity index (HTC-CI) scores were similar between the groups, but overall survival with an HCT-CI of at least 3 was lower compared with a score less than 3 (76% vs 98%; P = .005). Median donor T-cell chimerism among older patients was 64% and 60% at 1 and 3 years, respectively, and was similar to that of younger patients. Increased B regulatory cells potentially contributed to low alloreactivity and mutual donor-recipient tolerance in older patients. Effect of comorbidities rather than age alone may be a more important determinant of suitability for FCC HSCT in older patients.

Bone Marrow Failure in Children: Approach to Diagnosis and Treatment

Bone marrow failure has many different etiologies, including genetic defects which manifest with specific syndromes, as well as acquired conditions as a result of insults to the bone marrow leading to aplasia. The clinical picture is varied and clues for the underlying cause may or may not be evident at the time of presentation, frequently leading to a complex workup with a battery of tests often done to rule out genetic defects. The treatment approach for bone marrow failure is very dependent on the underlying cause, which makes it all the more critical to have an accurate diagnosis. First line management essentially consists of either hematopoietic stem cell transplant or immunosuppressive therapy. In this review authors will provide a broad look at the causes of bone marrow failure, the stepwise diagnostic algorithm and the approach to decision making for treatment. Fine details of each cause, and of each treatment modality are beyond the scope of this review which aims to provide an overview.

Allogeneic Hematopoietic Cell Transplantation in Patients Aged 50Years or Older with Severe Aplastic Anemia

We report on 499 patients with severe aplastic anemia aged ≥ 50years who underwent hematopoietic cell transplantation (HCT) from HLA-matched sibling (n = 275, 55%) or HLA-matched (8/8) unrelated donors (n = 187, 37%) between 2005 and 2016. The median age at HCT was 57.8 years; 16% of patients were 65 to 77years old. Multivariable analysis confirmed higher mortality risks for patients with performance score less than 90% (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.03 to 1.92; P = .03) and after unrelated donor transplantation (HR, 1.47; 95% CI, 1 to 2.16; P = .05). The 3-year probabilities of survival for patients with performance scores of 90 to 100 and less than 90 after HLA-matched sibling transplant were 66% (range, 57% to 75%) and 57% (range, 47% to 76%), respectively. The corresponding probabilities after HLA-matched unrelated donor transplantation were 57% (range, 48% to 67%) and 48% (range, 36% to 59%). Age at transplantation was not associated with survival, but grades II to IV acute graft-versus-host disease (GVHD) risks were higher for patients aged 65years or older (subdistribution HR [sHR], 1.7; 95% confidence interval, 1.07 to 2.72; P = .026). Chronic GVHD was lower with the GVHD prophylaxis regimens calcineurin inhibitor (CNI) + methotrexate (sHR, .52; 95% CI, .33 to .81; P = .004) and CNI alone or with other agents (sHR, .27; 95% CI, .14 to .53; P < .001) compared with CNI + mycophenolate. Although donor availability is modifiable only to a limited extent, choice of GVHD prophylaxis and selection of patients with good performance scores are key for improved outcomes.

Autoimmune hemolytic anemia, autoimmune neutropenia and aplastic anemia in the elderly

The physiology of the immune system involves morphologic and functional changes occurring along ageing, with a decrease in immune response and an increase in autoimmune phenomena, even in the absence of overt disese. Autoimmune cytopenias, namely autoimmune hemolytic anemia (AIHA), chronic idiopathic neutropenia (CIN) and aplastic anemia (AA), show different epidemiologic predilection, but are increasingly diagnosed in the elderly, where complications and comorbidities are more frequent. A systematic review of recent literature, shows that comorbidities as well as underlying deficiencies, medications, neoplasms, and, pathophysiologic chronic organ failures, frequently challenge the differential diagnosis in this setting and should always be evaluated and excluded. Complications, particularly infections and thrombosis for AIHA, and bleeding for AA, should be monitored and promptly treated. Treatment choice should be carefully weighed on the individual general condition and comorbidities, granted that intense primary care and support (including evidence-based transfusion policies) are provided. Finally, bone marrow histology is highly advisable in the elderly, both at diagnosis to detect underlying conditions, and along the follow-up to monitor possible bone marrow failure or neoplastic evolution.

Aplastic anemia in the elderly: a nationwide survey on behalf of the French Reference Center for Aplastic Anemia

Aplastic anemia is a rare but potentially life-threatening disease that may affect older patients. Data regarding the treatment of aplastic anemia in this ageing population remains scarce. We conducted a retrospective nationwide multicenter study in France to examine current treatments for aplastic anemia patients over 60 years old. Our aims were to evaluate efficacy and tolerance, and to analyze predictive factors for response and survival. Over the course of a decade, 88 patients (median age 68.5 years) were identified in 19 centers, with a median follow up of 2.7 years; 21% had very severe and 36% severe aplastic anemia. We analyzed 184 treatment lines, mostly involving the standard combination of anti-thymocyte globulin and cyclosporine-A (33%), which was also the most frequent first-line treatment (50%). After first-line therapy, 32% of patients achieved a complete response, and 15% a partial response. Responses were significantly better in first line and in patients with good performance status, as well as in those that had followed an anti-thymocyte globulin and cyclosporine-A regimen (overall response rate of 70% after first-line treatment). All treatments were well tolerated by patients, including over the age of 70. Three-year survival was 74.7% (median 7.36 years). Age, Charlson comorbidity index and very severe aplastic anemia were independently associated with mortality. Age, per se, is not a limiting factor to aplastic anemia treatment with anti-thymocyte globulin and cyclosporine-A; this regimen should be used as a first-line treatment in elderly patients if they have a good performance status and low comorbidity index score.

Recent Advances and Long-Term Results of Medical Treatment of Acquired Aplastic Anemia: Are Patients Cured?

Horse antithymocyte globulin plus cyclosporine remains standard immunosuppressive therapy in severe aplastic anemia, with hematologic response rates of 60% to 70%. In those refractory to this regimen, a second course of therapy with rabbit antithymocyte globulin plus cyclosporine or alemtuzumab produces responses in 30% to 40%. Eltrombopag, a thrombopoietin receptor agonist, showed activity as a single agent in those refractory to initial immunosuppression with hematologic response rates of 40% to 50%. When combined with immunosuppression as frontline therapy, eltrombopag increased the rate of overall and complete response rates. Longer follow-up is needed to better define these outcomes.

Nationwide survey on the use of horse antithymocyte globulins (ATGAM) in patients with acquired aplastic anemia: A report on behalf of the French Reference Center for Aplastic Anemia

Antithymocyte globulins (ATG) plus cyclosporine (CSA) is the gold standard immunosuppressive treatment (IST) for patients with aplastic anemia. A prospective randomized trial showed in 2011 that hATG was superior to rabbit ATG for first-line treatment of severe AA. The French Health Agency (ANSM) permitted a patient-named authorization for temporary use (ATU) program of hATG (ATGAM, Pfizer) in patients with AA in 2011 since commercial access to hATG is not approved. We took advantage of this program to analyze the outcomes of 465 patients who received antithymocyte globulins (ATGAM) plus CSA as first line treatment (n = 379; 81.5%), or for refractory (n = 26) or relapsed disease (n = 33), from September 2011 to March 2017. In the entire cohort one year, 72% of the patients had partial and 13% had complete response, with worse response for patients with severe AA and a longer interval between diagnosis and IST (more than 6 months). Severe adverse events were mainly linked to infections (24%), hemorrhages (6%), and elevated liver function tests (5%). Overall at 12 months, 9.7% of patients required second line IST and 15.6% received transplantation. Fifty-five patients died during the study mainly because of infections (53%). Factors predicting independently worse survival were age over 40 years, neutrophils less than 0.5 × 10⁹ /L, male gender and longer delay between diagnosis and hATG (>6 months period). This study does illustrate the results of ATGAM with CSA in a true-life perspective and confirms ATGAM as standard of care IST to treat patients with AA not eligible for HSCT.

Incidence and outcome of acquired aplastic anemia: real-world data from patients diagnosed in Sweden from 2000-2011

A plastic anemia is a rare life-threatening disease. However, since the introduction of immunosuppressive therapy and allogeneic stem cell transplantation, the outcome has improved considerably, and the 5-year survival is reported to be 70–80% in selected patient cohorts. Yet, contemporary population-based data on incidence and survival are lacking. We performed a national retrospective study to determine the incidence, treatment, and survival of patients with aplastic anemia diagnosed in Sweden from 2000–2011. Patients were included via the National Patient Registry, and diagnosed according to the Camitta criteria. In total, 257 confirmed cases were identified, with an overall incidence of 2.35 (95% CI: 2.06–2.64) cases per million inhabitants per year. Median age was 60 years (range: 2–92), and median follow up was 76 (0–193) months. Primary treatments included immunosuppressive therapy (63%), allogenic stem cell transplantation (10%), or single-agent cyclosporine/no specific therapy (27%). The 5-year survival was 90.7% in patients aged 0–18 years, 90.5% in patients aged 19–39 years, 70.7% in patients aged 40–59 years, and 38.1% in patients aged ≥60 years. Multivariate analysis showed that age (both 40–59 and ≥60 age groups), very severe aplastic anemia and single-agent cyclosporine/no specific therapy were independent risk factors for inferior survival. In conclusion, younger aplastic anemia patients experience a very good long-term survival, while that of patients ≥60 years in particular remains poor. Apparently, the challenge today is to improve the management of older aplastic anemia patients, and prospective studies to address this medical need are warranted.

Eltrombopag Added to Standard Immunosuppression for Aplastic Anemia

BACKGROUND

Acquired aplastic anemia results from immune-mediated destruction of bone marrow. Immunosuppressive therapies are effective, but reduced numbers of residual stem cells may limit their efficacy. In patients with aplastic anemia that was refractory to immunosuppression, eltrombopag, a synthetic thrombopoietin-receptor agonist, led to clinically significant increases in blood counts in almost half the patients. We combined standard immunosuppressive therapy with eltrombopag in previously untreated patients with severe aplastic anemia.

METHODS

We enrolled 92 consecutive patients in a prospective phase 1-2 study of immunosuppressive therapy plus eltrombopag. The three consecutively enrolled cohorts differed with regard to the timing of initiation and the duration of the eltrombopag regimen (cohort 1 received eltrombopag from day 14 to 6 months, cohort 2 from day 14 to 3 months, and cohort 3 from day 1 to 6 months). The cohorts were analyzed separately. The primary outcome was complete hematologic response at 6 months. Secondary end points included overall response, survival, relapse, and clonal evolution to myeloid cancer.

RESULTS

The rate of complete response at 6 months was 33% in cohort 1, 26% in cohort 2, and 58% in cohort 3. The overall response rates at 6 months were 80%, 87%, and 94%, respectively. The complete and overall response rates in the combined cohorts were higher than in our historical cohort, in which the rate of complete response was 10% and the overall response rate was 66%. At a median follow-up of 2 years, the survival rate was 97%; one patient died during the study from a nonhematologic cause. Marked increases in bone marrow cellularity, CD34+ cell number, and frequency of early hematopoietic progenitors were noted. Rates of relapse and clonal evolution were similar to our historical experience. Severe rashes occurred in two patients, resulting in the early discontinuation of eltrombopag.

CONCLUSIONS

The addition of eltrombopag to immunosuppressive therapy was associated with markedly higher rates of hematologic response among patients with severe aplastic anemia than in a historical cohort. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT01623167 .).

[Antithymocyte/Antilymphocyte globulin plus cyclosporine A therapy for the treatment of older patients with severe aplastic anemia]

目的

评估老年（≥60岁）重型再生障碍性贫血（SAA）患者接受兔抗人胸腺细胞球蛋白（rATG）／猪抗人淋巴细胞球蛋白（pALG）联合环孢素A(CsA）的强烈免疫抑制治疗（IST）方案的疗效和安全性。

方法

回顾性分析16例老年SAA患者接受rATG/pALG+CsA治疗的血液学反应率和安全性，分析影响疗效的相关因素。

结果

16例患者男13例，女3例，中位年龄63.5(60~79）岁，其中60~69岁13例，≥70岁3例；SAA患者9例，极重型AA(VSAA）患者7例；9例患者接受rATG治疗，7例患者接受pALG治疗。16例患者均顺利完成rATG/pALG治疗，治疗后早期死亡2例（12.5%），均为VSAA患者（2/7, 28.6%）；IST后6个月9例（56.3%）患者获得血液学反应，5例无治疗反应。9例应用rATG的患者有2例获得血液学反应，7例应用pALG患者全部获得血液学反应，差异有统计学意义（22.2％对100.0%，P=0.003）。rATG/pALG+CsA相关不良反应轻微，经对症治疗好转。

结论

老年SAA接受rATG/pALG联合CsA的IST方案仍可获较好血液学反应；VSAA患者早期死亡率高，治疗风险大；pALG治疗老年SAA疗效可能优于rATG。

How I treat acquired aplastic anemia. Blood. 2017;129:1428-1436. [PMID: 28096088 DOI: 10.1182/blood-2016-08-693481]

Acquired severe aplastic anemia (SAA) is a rare hematologic disease associated with significant morbidity and mortality. Immune destruction of hemopoietic stem cells plays an important role in pathogenesis, as shown by successful treatment with immunosuppressive agents, leading to transfusion independence or complete recovery of peripheral blood counts in a proportion of patients. Growth factors can be combined with immunosuppressive therapy (IST) and may improve response rates, as recently shown with thrombopoietin analogs. Anabolic steroids may still play a role in combination with IST. The problem with IST is failure to respond and the development of late clonal disorders. Bone marrow transplantation (BMT) is the other therapeutic option: a matched sibling donor remains the best choice. For patients lacking a matched family donor, unrelated donors can be readily found, although mostly for patients of Caucasian origin. Other BMT options include unrelated cord blood or mismatched family donors. Acute and chronic graft-versus-host disease remain important complications of BMT. Patient age is a strong predictor of outcome for both IST and BMT, and must be considered when designing therapeutic strategies. Early diagnosis and treatment, as well as long-term monitoring, remain crucial steps for successful treatment of SAA.

Transplantation for bone marrow failure: current issues

The preferred treatment of idiopathic aplastic anemia (AA) is allogeneic hematopoietic stem cell transplantation (HSCT) from a human leukocyte antigen (HLA)-identical sibling donor. Transplantation from a well-matched unrelated donor (MUD) may be considered for patients without a sibling donor after failure of immunosuppressive therapy, as may alternative transplantation (mismatched, cord blood or haplo-identical HSCT) for patients without a MUD. HSCT may also be contemplated for congenital disorders in cases of pancytopenia or severe isolated cytopenia. Currently, HSCT aims are not only to cure patients but also to avoid long-term complications, notably chronic graft-versus-host disease (GVHD), essential for a good quality of life long term. This paper summarizes recent advances in HSCT for idiopathic and inherited AA disorders. The effect of age on current transplantation outcomes, the role of transplantation in paroxysmal nocturnal hemoglobinuria, and the prevention of GVHD are also discussed. Emerging strategies regarding the role of up-front unrelated donor and alternative donor HSCT in idiopathic AA, along with advances in the treatment of clonal evolution in Fanconi anemia, are also examined.

Eltrombopag for the treatment of aplastic anemia: current perspectives

Aplastic anemia (AA) is a potential life-threatening hematopoietic stem cell (HSC) disorder resulting in cytopenia. The mainstays of treatment for AA are definitive therapy to restore HSCs and supportive measures to ameliorate cytopenia-related complications. The standard definitive therapy is HSC transplantation for young and medically fit patients with suitable donors and immunosuppressive therapy (IST) with antithymocyte globulin and cyclosporine for the remaining patients. A significant proportion of patients are refractory to IST or relapse after IST. Various strategies have been explored in these patients, including second course of antithymocyte globulin, high-dose cyclophosphamide, and alemtuzumab. Eltrombopag, a thrombopoietin mimetic, has recently emerged as an encouraging and promising agent for patients with refractory AA. It has demonstrated efficacy in restoring trilineage hematopoiesis, and this positive effect continues after discontinuation of the drug. There are ongoing clinical trials exploring the role of eltrombopag as a first-line therapy in moderate to severe AA and a combination of eltrombopag with IST in severe AA.

Diagnosing and treating severe aplastic anemia

Severe aplastic anemia is a disorder of stem cell failure, leading to pancytopenia. The condition is characterized by an impairment of the function of hematopoietic stem cells. Patients typically have fatigue, infections, and increased or unusual bleeding. A bone marrow biopsy establishes the diagnosis. Treatment includes hematopoietic stem cell transplant or immunosuppressive therapy.

Outcome of children with severe acquired aplastic anemia treated with rabbit antithymocyte globulin and cyclosporine A

OBJECTIVE

To evaluate the outcome of children with severe acquired aplastic anemia treated with rabbit antithymocyte globulin and cyclosporine as first-line treatment at this institution.

METHODS

Retrospective analysis of 26 pediatric patients with aplastic anemia, treated between 1996 and 2011 with rabbit antithymocyte globulin plus cyclosporine.

RESULTS

The overall response rate at six months was 34.6% (9/26), and the cumulative incidence of relapse was 26.5% (95% confidence interval [CI]: 1.4%-66%) at 5 years. The cumulative incidence of clonal evolution after immunosuppressive therapy was 8.3% (95% CI: 0.001%-53.7%) at five years with both clonal evolutions in non -responders who acquired monosomy 7 karyotype. The overall survival at five years was 73.6% (95% CI: 49.2%-87.5%).

CONCLUSIONS

The present results confirm the poor response rate with rabbit antithymocyte globulin as first therapy in pediatrics patients, similar to what has been reported for patients of all ages. This confirmation is problematic in Brazil, given the lack of horse antithymocyte globulin in many markets outside the United States.

Clinical course of patients with aplastic anemia or myelodysplastic syndrome associated with persistent neutropenia

Patients with aplastic anemia (AA) or myelodysplastic syndrome (MDS) often have persistent severe neutropenia and are susceptible to infectious complications. We retrospectively reviewed the clinical course of patients with AA or MDS who had neutropenia (neutrophil count < 500/µl) for more than 25 days. A total of 46 patients, 11 with AA and 35 with MDS, were included. Twenty-three patients had infectious events (IE), and the cumulative incidence of IE was 30% at 6 months and 51% at 1 year. The cumulative incidence of IE was 67% at 1 year in 30 patients who experienced very severe neutropenia of less than 200/µl. Overall survival in all patients was 76% at 6 months and 65% at 1 year. In a multivariate analysis, male sex, underlying diseases, and a neutrophil count of less than 200/µl as a time-dependent covariate significantly affected IE. In analyses that excluded patients with AA, male sex was the only factor. In conclusion, severe neutropenia was significantly associated with IE in patients with AA or MDS, and IE might be lethal. When we only considered patients with MDS, the neutrophil count alone could not be used to predict the prognosis.

Decreased infection-related mortality and improved survival in severe aplastic anemia in the past two decades

BACKGROUND

Persistent neutropenia associated with severe aplastic anemia (SAA) is an important risk factor for development of life-threatening infections. Earlier studies underscored the high mortality associated with invasive fungal infections (IFIs) in SAA. However, little is known about the current patterns of infections and the impact of advances in anti-infective therapy on survival in SAA.

METHODS

We reviewed the records of 174 patients with SAA admitted to the Hematology Branch at NHLBI from 1989 to 2008 who were unresponsive to initial immunosuppressive therapy (IST) at 6 months. Three patient groups determined by IST protocol and time interval were compared: group 1 (43 patients; December 1989-October 1996), group 2 (51 patients; November 1996-October 2002), and group 3 (80 patients; November 2002-April 2008). Outcome variables included infections, patterns of resistance, survival, and infection-related mortality.

RESULTS

During the past 2 decades, infection-related mortality decreased from 37% in group 1 to 11% in group 3 (P < .001), and the frequency of IFIs decreased from 49% in group 1 to 8% in group 3 (P < .001). Overall 5-year survival for all patients (n = 420) increased from 64% in group 1 to 79% in group 3 (P < .001). Among non-responders (n = 174), it increased from 23% in group 1 to 57% in group 3 (P < .001). In multivariate analysis, younger age, absolute neutrophil count > 200 cells/μL before IST, absence of IFIs, and use of voriconazole were independently predictive of survival.

CONCLUSION

During the past 2 decades, there has been a significant decrease in IFIs, infection-related mortality, and overall mortality in patients with SAA unresponsive to initial IST.

Aplastic Anemia: First-line Treatment by Immunosuppression and Sibling Marrow Transplantation

Newly diagnosed aplastic anemia is a serious condition, with more than 75% (higher in young patients) becoming long-term survivors if diagnosed and treated appropriately. First-line treatment approaches include immunosuppressive treatment using the combination of antithymocyte globulin and cyclosporine A for patients without a sibling donor and HLA identical sibling transplant for patients younger than age 40 with a donor. Best transplant strategies have been defined and include conditioning with cyclophosphamide and antithymocyte globulin, marrow as a stem cell source, and graft-versus-host diease prophylaxis using cyclosporine A and methotrexate. It is against these standard treatment approaches that any therapeutic progress has to be measured.

Optimization of therapy for severe aplastic anemia based on clinical, biologic, and treatment response parameters: conclusions of an international working group on severe aplastic anemia convened by the Blood and Marrow Transplant Clinical Trials Network, March 2010

Although recent advances in therapy offer the promise for improving survival in patients with severe aplastic anemia (SAA), the small size of the patient population, lack of a mechanism in North America for longitudinal follow-up of patients, and inadequate cooperation among hematologists, scientists, and transplant physicians remain obstacles to conducting large studies that would advance the field. To address this issue, the Blood and Marrow Transplant Clinical Trials Network (BMT CTN) convened a group of international experts in March 2010 to define the most important questions in the basic science, immunosuppressive therapy (IST), and bone marrow transplantation (BMT) of SAA and propose initiatives to facilitate clinical and biologic research. Key conclusions of the working group were: (1) new patients should obtain accurate, expert diagnosis and early identification of biologic risk; (2) a population-based SAA outcomes registry should be established in North America to collect data on patients longitudinally from diagnosis through and after treatment; (3) a repository of biologic samples linked to the clinical data in the outcomes registry should be developed; (4) innovative approaches to unrelated donor BMT that decrease graft-versus-host disease are needed; and (5) alternative donor transplantation approaches for patients lacking HLA-matched unrelated donors must be improved. A partnership of BMT, IST, and basic science researchers will develop initiatives and partner with advocacy and funding organizations to address these challenges. Collaboration with similar study groups in Europe and Asia will be pursued.

Clinical course of non-severe aplastic anemia in adults

The clinical course of non-severe aplastic anemia is variable, and risk factors related to disease progression are not well known. We reviewed clinical and laboratory data of the patients who were diagnosed with non-severe aplastic anemia from 1997 to 2007 at Seoul National University Hospital and analyzed the clinical course and outcomes in these patients. We defined non-severe aplastic anemia as hypocellular marrow with cytopenia in the peripheral blood, which does not meet the criteria for severe aplastic anemia (at least two of the following: ANC < 500/microl, platelet < 20,000/microl or reticulocyte < 20,000/microl). Among a total of 96 patients, 53 (55.2%) were male and the median age was 37.6 years old. As much as 41.7% (40) of the patients were initially asymptomatic. Sixty-two patients who were treated with oxymetholone, ATG/ALG, cyclosporin or other agents after initial diagnosis showed significantly lower levels of initial hemoglobin, red blood cell count and platelet count than those who did not receive any treatment. During the follow-up period, 18 patients progressed to severe aplastic anemia. Their median age was 29.9 years and the median progression time was 18 months. Initial white blood cell count and absolute neutrophil count in the evolution group tended to be lower than in the other group. The patients whose thrombocytopenia did not respond to treatment showed markedly higher frequency of progression to severe aplastic anemia. Treatment itself and responsiveness in reticulocyte and absolute neutrophil count were not correlated with their clinical courses. Sixteen patients showed overall improvement, whereas three patients developed secondary hematologic disease, acute myeloid leukemia, myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria. Non-severe aplastic anemia has a relatively indolent and mild clinical course. However, 18.8% of the study population progressed to severe disease. White blood cell and absolute neutrophil count at diagnosis and treatment responsiveness of thrombocytopenia were associated with disease progression. Careful monitoring and early management are needed for patients at risk.

S-phase fraction as a useful marker for prognosis and therapeutic response in patients with aplastic anemia

BACKGROUND

The functional definition of aplastic anemia (AA) is the failure of hematopoietic stem cells to proliferate. The aim of the present study was to analyze the S-phase fraction (SPF) (proliferative activity) in patients with AA at diagnosis to explore its relationship with disease characteristics and its value in discriminating among patients with different prognoses. We also investigated whether the SPF value influenced the response to immunosuppressive therapy in AA patients.

PATIENTS AND METHODS

The analysis of SPF at the time of diagnosis was carried out by flow cytometry on peripheral blood samples from 53 consecutive patients with AA and 30 age- and sex-matched controls. All patients were given cyclosporine and followed up periodically to determine response to therapy.

RESULTS

Based on the median SPF, AA patients were divided into two groups: patients with SPF < 0.59% (n = 27) and patients with SPF > 0.59% (n = 26). An SPF > 0.59% was associated with advanced age (P = .02) and elevated serum LDH level (P = .01). Patients with an SPF > 0.59% also had a higher incidence of paroxysmal nocturnal hemoglobinuria and cytogenetic abnormalities. During a median follow-up of 18 months, 3.7% of patients with SPF < or = 0.59 and 11.5% of patients with SPF > 0.59% developed dysplasia and one patient with SPF > 0.59% converted into AML. A significantly higher (P = .018) overall response rate of 53.9% was found in patients with SPF > 0.59% versus 22.2% of patients with SPF < or = 0.59% at 6 months.

CONCLUSIONS

Independently of the peripheral blood count, the SPF at diagnosis may provide information on the expected response to immunosuppressive therapy and the propensity for disease to evolve into MDS/AML. Hence, SPF may serve as an early indicator for the evolution of MDS/AML in patients with AA and thus contribute to therapeutic decisions.

Outcome of allogeneic hematopoietic cell transplantation from HLA-identical siblings for severe aplastic anemia in patients over 40 years of age

Patients with severe aplastic anemia (SAA) over 40 years of age are often not offered treatment with hematopoietic cell transplantation (HCT) because of concerns about treatment-related morbidity or mortality. To evaluate this risk, we analyzed outcomes after allogeneic HCT from HLA-identical sibling donors for all older patients with SAA at our center since 1988. The 23 consecutive patients ranged in age from 40 to 68 years. The conditioning regimen was cyclophosphamide (200 mg/kg) and horse antithymocyte globulin. Methotrexate and cyclosporine were given for postgrafting immunosuppression. The cumulative incidences of grades II, III, and IV acute graft-versus-host-disease were 30%, 4%, and 0%, respectively; that for chronic GVHD was 26%. With a median follow-up of 9.1 years, overall survival was 65%. Documented infections within 1 month before HCT were significantly associated with risk of early treatment-related mortality (P < .001). The median time to discontinuation of posttransplant immunosuppression was 6.2 (range: 5.9-92.0) months. Three patients developed superficial basal cell carcinoma between 5.5 and 15 years after HCT. Our data favor a practice of extending HLA-identical sibling HCT for treatment of SAA in patients older than 40 years of age who are without significant medical comorbidities.

Single-Center Experience: immunosuppressive therapy as frontline treatment for 33 children with acquired severe aplastic anemia

The authors retrospectively analyzed the records of 33 children with acquired severe aplastic anemia (SAA) diagnosed from July 1998 to October 2007 and first treated by immunosuppressive therapy (IST). Serial hematologic parameters, complications, transfusion requirements, and time to response were assessed. Allogeneic hematopoietic stem cell transplantation (HSCT) was attempted in 7 patients after failure of IST (n = 6) or relapse following an initial response to IST (n = 1). One child died of post-transplant lymphoproliferative disorder. Thirty of the 33 patients are alive and well after a median follow-up of 45 months (range, 7-116 months). Overall (transfusion-independent) response to IST was 73% (24/33). The actuarial 5 years survival rate was 89.4%. In this study, all patients with SAA received IST as standard front-line therapy. Approximately three-fourths of patients with SAA have durable recovery and excellent overall survival.

Diagnosis and treatment of acquired aplastic anemia

Acquired severe aplastic anemia can be treated successfully with either immunosuppressive therapy or bone marrow transplantation. Although immunosuppressive therapy can be readily administered to all patients, it is not a curative approach and is associated with a higher risk of clonal evolution than is transplantation, which yields rapid and long-lasting hematologic remission. This article reviews the key diagnostic and prognostic factors that influence the choice of therapy in patients with acquired aplastic anemia.

Predicting response to immunosuppressive therapy and survival in severe aplastic anaemia

Horse anti-thymocyte globulin (h-ATG) and ciclosporin are the initial therapy for most patients with severe aplastic anaemia (SAA), but there is no practical and reliable method to predict response to this treatment. To determine whether pretreatment blood counts discriminate patients with SAA who have a higher likelihood of haematological response at 6 months to immunosuppressive therapy (IST), we conducted a single institution retrospective analysis on 316 SAA patients treated with h-ATG-based IST from 1989 to 2005. In multivariate analysis, younger age, higher baseline absolute reticulocyte count (ARC), and absolute lymphocyte count (ALC) were highly predictive of response at 6 months. Patients with baseline ARC > or = 25 x 10(9)/l and ALC > or = 1 x 10(9)/l had a much greater probability of response at 6 months following IST compared to those with lower ARC and ALC (83% vs. 41%, respectively; P < 0.001). This higher likelihood of response translated to greater rate of 5-year survival in patients in the high ARC/ALC group (92%) compared to those with a low ARC/ALC (53%). In the era of IST, the baseline ARC and ALC together serve as a simple predictor of response following IST, which should guide in risk stratification among patients with SAA.

Treatment strategies for patients with severe aplastic anemia

Treatment strategies for patients with severe aplastic anemia (SAA), depend on the severity of the disease, the age of the patient and the availability of a family donor. Progress in the past has included the early use of combined immunosuppressive therapy (IST) and better matching strategies to select unrelated donors. Currently, the actuarial 10-year survival in 2479 patients registered within the European Group for Blood and Marrow Transplantation (EBMT), is 73 and 68% for patients receiving first-line BMT or IST. The outcome of BMT has significantly improved since 1996, and this is true for both matched sibling donor BMT as well as for alternative donor BMT. Survival is significantly better in children (<16 years) as compared with adults (79 vs 68%, P<0.0001). In contrast, there has been no significant improvement over time for patients receiving IST. Again, results were significantly better in children compared with adults (81 versus 70%, P=0.001), especially in very severe aplasia (83 versus 62%, P=0.0002). This report outlines some of these results as a basis for treatment strategies in SAA.

Allogeneic stem cell transplantation for aplastic anemia

Aplastic anemia encompasses a heterogeneous group of diseases with distinct pathophysiologies and a common clinical endpoint of marrow failure. Patients with severe aplastic anemia can be treated with immunosuppressive therapy (IST) or hematopoietic stem cell transplantation (HSCT). Over the last 30 years, advances in both treatment modalities have significantly improved the prognosis for this disease; yet this evolution complicates the central therapeutic question in aplastic anemia: which patients should receive IST and which ones should receive HSCT as front-line therapy? In this review, we describe the major improvements that have occurred in transplantation for aplastic anemia in the last 3 decades. We then outline a framework for deciding which patients should be considered for upfront transplantation.

Aplastic anemia: pathogenesis and treatment

This review highlights some of the contributions that have appeared in the literature in the past decade on the pathogenesis and treatment of aplastic anemia (AA). This summary is brief because the field is vast, spaning from stem cell biology to stem cell disorders, from autoimmunity to transplantation, from graft-versus-host disease to late effects. The immune pathogenesis of AA is now based on several lines of evidence and will be discussed. Immunosuppressive therapy (IST) remains an important option for AA patients who are not candidates for transplantation. Favorable prognostic indicators for IST are young age and a short interval from diagnosis; the neutrophil count seems to have lost its predictive value with current antithymocyte globulin-cyclsoporin combination therapy. The outcome of allogeneic bone marrow transplantations has significantly improved in the past decade, particularly in the unrelated donor setting, to such an extent that treatment strategies may be affected. A short interval between diagnosis and treatment will also improve results for bone marrow transplantation; these rare patients should be referred to an experienced center immediately.

Supportive management of pregnancy-associated aplastic anemia

OBJECTIVE

To examine maternal and fetal outcomes of pregnancy-associated aplastic anemia treated with supportive care.

METHODS

From January 1995 to December 2004, 14 women newly diagnosed as having pregnancy-associated aplastic anemia were recruited for the study.

RESULTS

Diagnosis was made during the second or third trimester for 11 (78%) of the 14 patients, and 3 of the 8 severe cases of aplastic anemia were diagnosed at initial presentation. All patients had conservative management with transfusions but no specific immunologic or hormonal therapy during pregnancy. Of the 12 women eligible for follow-up, 1 achieved complete remission and 8 achieved partial remission after delivery. The pregnancies progressed uneventfully in most cases.

CONCLUSIONS

This study demonstrated favorable maternal and neonatal outcomes with transfusion support alone for pregnancy-associated aplastic anemia.