RARE DISEASE
Rare aplastic anemia
Rare aplastic anemia
Rare aplastic anemia
Drug discovery
3
drugs
With orphan designations
Overview
Aplastic anemia is a rare bone marrow failure disorder characterized by pancytopenia and hypocellular marrow due to immune-mediated destruction of hematopoietic stem cells. Etiologies include idiopathic causes (50%), viral infections, toxins, radiation, or inherited syndromes. Diagnosis requires exclusion of other causes, bone marrow biopsy, and cytogenetic testing. First-line therapies include hematopoietic stem cell transplantation (HSCT) for eligible patients or immunosuppression with antithymocyte globulin (ATG) and cyclosporine [1][3][11].
Population
Annual incidence: 2–3 cases per million in Western countries, higher in East Asia (≥4 per million) [4][9][12].
Biphasic age distribution: peaks in adolescents/young adults (15–25 years) and older adults (>60 years) [12][18].
Slight male predominance in some cohorts; higher prevalence in Asian populations [4][12][16].
Therapies
HSCT: Curative for patients <40 years with matched donors (5-year survival: 75–100%) [3][11][13].
Immunosuppressive therapy (IST): First-line for non-transplant candidates—equine ATG + cyclosporine ± eltrombopag (response rates: 60–80%) [3][8][13].
Supportive care: Transfusions, antimicrobial prophylaxis, and growth factors to manage cytopenias [5][8][16].
Categories: rare hematological diseases, rare transplant-related disorders
Research Papers
273 drug discovery papers about Rare aplastic anemia, with 2 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
273 drug discovery papers about Rare aplastic anemia, with 2 first-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-06-23 | ID #670 A Rare and Severe Complication: Aplastic Anemia After a Single Cycle of Temozolomide in a Child with Recurrent Ependymoma
Abstract Background Temozolomide is an alkylating chemotherapeutic agent commonly used in the management of high-grade central nervous system (CNS) tumors. While myelotoxicity, most commonly manifesting as thrombocytopenia, is a recognized adverse effect, profound myelosuppression in otherwise chemotherapy-naïve patients is rare. Severe aplastic anemia represents an even more uncommon complication of temozolomide therapy, occurring in fewer than 1% of treated patients, reported predominantly in adults (mean age 60.7 years) and associated with substantial morbidity and mortality. Case/Methods A 12-year-old female experienced relapse of PF-A ependymoma approximately two years after initial treatment with gross total resection and focal radiation. At recurrence, only near-total resection was feasible. Given the proximity to prior radiation and location of residual disease, repeat radiation was deemed unsafe. The patient was therefore initiated on oral temozolomide at a standard dose for high-grade CNS tumors (200 mg/m² daily for 5 days). Following a single cycle of therapy, she developed a delayed hypersensitivity reaction characterized by urticaria and emesis three days after completion, which resolved with epinephrine and corticosteroids. Approximately 3.5 weeks after temozolomide administration, she presented with profound pancytopenia, manifesting as acute-onset wet purpura and active mucosal bleeding. Due to the severity of cytopenias and minimal response to transfusion support, a bone marrow biopsy was performed, demonstrating marked aplasia with <5% overall cellularity, nearly absent granulopoiesis and megakaryopoiesis, and markedly decreased erythropoiesis. The patient was treated with prophylactic antibiotics, granulocyte colony-stimulating factor, and romiplostim, resulting in partial hematologic recovery within four weeks. Conclusion Severe aplastic anemia represents a rare but potentially fatal complication of temozolomide therapy in patients with CNS malignancies. To our knowledge, this represents the youngest reported case of temozolomide-induced aplastic anemia, underscoring that this complication can occur in children and highlighting the importance of early recognition and proactive hematologic surveillance, even after a single cycle of treatment. 1. Villano JL, Letarte N, Yu JM, Abdur S, Bressler LR. Hematologic adverse events associated with temozolomide. Cancer Chemother Pharmacol. 2012 Jan;69(1):107-13. doi: 10.1007/s00280-011-1679-8. Epub 2011 May 26. PMID: 21614470. 2. Park AK, Waheed A, Forst DA, Al-Samkari H. Characterization and prognosis of temozolomide-induced aplastic anemia in patients with central nervous system malignancies. Neuro Oncol. 2022 Jun 1;24(6):964-973. doi: 10.1093/neuonc/noab240. PMID: 34647594; PMCID: PMC9159424.
2026-06-10 | Anemia aplástica: diagnóstico, fisiopatologia imune e abordagens terapêuticas.
Introduction: Aplastic anemia is a rare, but potentially fatal, bone marrow failure syndrome characterized by hypocellular marrow and peripheral pancytopenia. The acquired variant is primarily immune-mediated, involving cytotoxic T lymphocytes, inflammatory cytokines, and functional destruction of hematopoietic stem cells. Objective: To systematically analyze the epidemiological, pathophysiological, diagnostic, prognostic, and mechanical factors related to aplastic anemia, with reference to immune pathophysiology, hematopoietic stem cell transplantation, immunosuppression, eltrombopag, relapse, clonal evolution, and emerging therapy. Methods: Searches were conducted throughout PubMed/MEDLINE, SciELO, ScienceDirect, and Portal CAPES from 2014 to 2024, using DeCS/MeSH descriptors in combination with Boolean operators. Workflow: Use of PICOS criteria, independent screening by two reviewers, assessment of risk of bias based on study design, and appropriate descriptive statistical synthesis. Results: 142 records were identified. After removing duplicates, title/abstract screening, full-text evaluation, and application of eligibility criteria, 37 studies were included in the qualitative synthesis. The findings reinforce that diagnosis needs to be based on a combined approach including blood count and reticulocytes, bone marrow aspirate and biopsy, and exclusion of secondary causes based on disease severity; the choice of TNF treatment is determined by age, severity, donor availability, comorbidities, and risk of complications. Conclusion: Modern management of aplastic anemia should be individualized and based on early diagnosis, risk stratification (including the use of prognostic models), transfusion support, anti-infective prophylaxis (and treatment when indicated), transplantation as appropriate, and immunosuppression with the incorporation of thrombopoietin receptor agonists.
2026-05-13 | Use of Thrombopoietin Receptor Agonists in Severe Aplastic Anemia During Pregnancy: A Case Report
Severe aplastic anemia (SAA) in pregnancy represents a rare but life-threatening clinical challenge. Standard therapies such as hematopoietic stem cell transplantation (HSCT) and immunosuppressive therapy are limited during pregnancy due to safety concerns, leaving supportive care as the mainstay. Thrombopoietin receptor agonists (TPO-RAs) such as eltrombopag have emerged as promising agents in refractory SAA, though evidence of their safety in pregnancy remains scarce. We present the case of a 27-year-old woman with SAA post-allogeneic bone marrow transplant who relapsed during subsequent pregnancies. Her disease course was characterized by recurrent pancytopenia, mixed chimerism, and repeated need for stem cell boosts. During pregnancy in 2023, discontinuation of cyclosporine led to worsening cytopenias, prompting reintroduction of cyclosporine and the continuation of eltrombopag. This combined approach, alongside G-CSF and stem cell boosts, contributed to favorable hematologic stabilization. She successfully delivered a healthy infant and achieved hematologic recovery following a third stem cell boost postpartum. This report highlights the potential utility of TPO-RAs during pregnancy when conventional therapy is limited, while emphasizing the need for vigilant monitoring of maternal–fetal outcomes. A review of the literature suggests that although routine use of eltrombopag in pregnancy is not recommended, it may be considered in refractory SAA cases with careful risk–benefit assessment. The case underscores the role of multidisciplinary care, individualized therapeutic planning, and the need for further studies on TPO-RAs in pregnancy-associated bone marrow failure syndromes.
2026-06-23 | ID #670 A Rare and Severe Complication: Aplastic Anemia After a Single Cycle of Temozolomide in a Child with Recurrent Ependymoma
Abstract Background Temozolomide is an alkylating chemotherapeutic agent commonly used in the management of high-grade central nervous system (CNS) tumors. While myelotoxicity, most commonly manifesting as thrombocytopenia, is a recognized adverse effect, profound myelosuppression in otherwise chemotherapy-naïve patients is rare. Severe aplastic anemia represents an even more uncommon complication of temozolomide therapy, occurring in fewer than 1% of treated patients, reported predominantly in adults (mean age 60.7 years) and associated with substantial morbidity and mortality. Case/Methods A 12-year-old female experienced relapse of PF-A ependymoma approximately two years after initial treatment with gross total resection and focal radiation. At recurrence, only near-total resection was feasible. Given the proximity to prior radiation and location of residual disease, repeat radiation was deemed unsafe. The patient was therefore initiated on oral temozolomide at a standard dose for high-grade CNS tumors (200 mg/m² daily for 5 days). Following a single cycle of therapy, she developed a delayed hypersensitivity reaction characterized by urticaria and emesis three days after completion, which resolved with epinephrine and corticosteroids. Approximately 3.5 weeks after temozolomide administration, she presented with profound pancytopenia, manifesting as acute-onset wet purpura and active mucosal bleeding. Due to the severity of cytopenias and minimal response to transfusion support, a bone marrow biopsy was performed, demonstrating marked aplasia with <5% overall cellularity, nearly absent granulopoiesis and megakaryopoiesis, and markedly decreased erythropoiesis. The patient was treated with prophylactic antibiotics, granulocyte colony-stimulating factor, and romiplostim, resulting in partial hematologic recovery within four weeks. Conclusion Severe aplastic anemia represents a rare but potentially fatal complication of temozolomide therapy in patients with CNS malignancies. To our knowledge, this represents the youngest reported case of temozolomide-induced aplastic anemia, underscoring that this complication can occur in children and highlighting the importance of early recognition and proactive hematologic surveillance, even after a single cycle of treatment. 1. Villano JL, Letarte N, Yu JM, Abdur S, Bressler LR. Hematologic adverse events associated with temozolomide. Cancer Chemother Pharmacol. 2012 Jan;69(1):107-13. doi: 10.1007/s00280-011-1679-8. Epub 2011 May 26. PMID: 21614470. 2. Park AK, Waheed A, Forst DA, Al-Samkari H. Characterization and prognosis of temozolomide-induced aplastic anemia in patients with central nervous system malignancies. Neuro Oncol. 2022 Jun 1;24(6):964-973. doi: 10.1093/neuonc/noab240. PMID: 34647594; PMCID: PMC9159424.
2026-06-10 | Anemia aplástica: diagnóstico, fisiopatologia imune e abordagens terapêuticas.
Introduction: Aplastic anemia is a rare, but potentially fatal, bone marrow failure syndrome characterized by hypocellular marrow and peripheral pancytopenia. The acquired variant is primarily immune-mediated, involving cytotoxic T lymphocytes, inflammatory cytokines, and functional destruction of hematopoietic stem cells. Objective: To systematically analyze the epidemiological, pathophysiological, diagnostic, prognostic, and mechanical factors related to aplastic anemia, with reference to immune pathophysiology, hematopoietic stem cell transplantation, immunosuppression, eltrombopag, relapse, clonal evolution, and emerging therapy. Methods: Searches were conducted throughout PubMed/MEDLINE, SciELO, ScienceDirect, and Portal CAPES from 2014 to 2024, using DeCS/MeSH descriptors in combination with Boolean operators. Workflow: Use of PICOS criteria, independent screening by two reviewers, assessment of risk of bias based on study design, and appropriate descriptive statistical synthesis. Results: 142 records were identified. After removing duplicates, title/abstract screening, full-text evaluation, and application of eligibility criteria, 37 studies were included in the qualitative synthesis. The findings reinforce that diagnosis needs to be based on a combined approach including blood count and reticulocytes, bone marrow aspirate and biopsy, and exclusion of secondary causes based on disease severity; the choice of TNF treatment is determined by age, severity, donor availability, comorbidities, and risk of complications. Conclusion: Modern management of aplastic anemia should be individualized and based on early diagnosis, risk stratification (including the use of prognostic models), transfusion support, anti-infective prophylaxis (and treatment when indicated), transplantation as appropriate, and immunosuppression with the incorporation of thrombopoietin receptor agonists.
2026-05-13 | Use of Thrombopoietin Receptor Agonists in Severe Aplastic Anemia During Pregnancy: A Case Report
Severe aplastic anemia (SAA) in pregnancy represents a rare but life-threatening clinical challenge. Standard therapies such as hematopoietic stem cell transplantation (HSCT) and immunosuppressive therapy are limited during pregnancy due to safety concerns, leaving supportive care as the mainstay. Thrombopoietin receptor agonists (TPO-RAs) such as eltrombopag have emerged as promising agents in refractory SAA, though evidence of their safety in pregnancy remains scarce. We present the case of a 27-year-old woman with SAA post-allogeneic bone marrow transplant who relapsed during subsequent pregnancies. Her disease course was characterized by recurrent pancytopenia, mixed chimerism, and repeated need for stem cell boosts. During pregnancy in 2023, discontinuation of cyclosporine led to worsening cytopenias, prompting reintroduction of cyclosporine and the continuation of eltrombopag. This combined approach, alongside G-CSF and stem cell boosts, contributed to favorable hematologic stabilization. She successfully delivered a healthy infant and achieved hematologic recovery following a third stem cell boost postpartum. This report highlights the potential utility of TPO-RAs during pregnancy when conventional therapy is limited, while emphasizing the need for vigilant monitoring of maternal–fetal outcomes. A review of the literature suggests that although routine use of eltrombopag in pregnancy is not recommended, it may be considered in refractory SAA cases with careful risk–benefit assessment. The case underscores the role of multidisciplinary care, individualized therapeutic planning, and the need for further studies on TPO-RAs in pregnancy-associated bone marrow failure syndromes.
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Drug Discovery Landscape
3 orphan drug designations for Rare aplastic anemia.
3 orphan drug designations for Rare aplastic anemia.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
allogeneic ex-vivo expanded placental adherent stromal cells | cell therapies | FDA | 2013-02-18 | — | Pluri Biotech Ltd. |
Etiocholanedione | small molecules | FDA | 1995-11-03 | — | SuperGen, Inc. |
Molgramostim | proteins | FDA | 1989-09-25 | — | Schering Corporation |
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