Safety and efficacy of eltrombopag in patients with aplastic anemia: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This article conducts a systematic review of eltrombopag combined with immunosuppressive therapy for the treatment of aplastic anemia (AA), to demonstrate the effectiveness and safety of eltrombopag.

METHODS

PubMed, Cochrane Library, Embase, OVID, Web of Science, China National Knowledge Infrastructure, and Wanfang databases were searched. Studies that met the inclusion criteria were collected, ranging from the establishment of the database to August 2023. Two reviewers performed meta-analyses using the Cochrane systematic review method and RevMan 5.3 software.

RESULTS

This meta-analysis enrolled 5 studies with a total of 542 AA patients, including 274 in the experimental group and 268 in the control group. Meta-analyses were performed for efficacy and adverse reactions. The endpoint of effects included 6-month complete response (CR), 6-month partial response (PR), and 6-month overall response (OR). Eltrombopag combined with immunotherapy showed significant improvements in 6-month CR (OR: 2.20; 95% CI;1.54-3.12; P < 0.0001) and 6-month OR (OR = 3.66, 95% CI 2.39-5.61, P < 0.001)compared to immunosuppressive therapy for AA patients. In terms of safety, eltrombopag combined with immunosuppressive therapy showed significantly increased pigment deposition and abnormal liver function compared to immunosuppressive therapy alone.

CONCLUSION

Compared to immunosuppressive therapy alone, eltrombopag combined with immunosuppressive therapy showed significant improvements in 6-month CR and 6-month OR. However, it also resulted in increased pigment deposition and abnormal liver function in terms of safety.

Eltrombopag can promote platelet implantation after allogeneic hematopoietic stem cell transplantation as safely and similarly to thrombopoietin

Background

Eltrombopag has demonstrated efficacy in treating low platelet (PLT) levels, but it remains unclear whether eltrombopag can promote PLT engraftment after hematopoietic stem cell transplantation (HSCT).

Methods

Forty-one HSCT patients received eltrombopag 50 mg/d from +1 day until PLT >50 × 109/L or 1 month after HSCT. Fifty-one patients in the same period received thrombopoietin (TPO) to promote PLT graft after HSCT and served as a control group.

Results

A total of 51 patients who applied TPO during the same period were treated as a control. In the eltrombopag group, the median time to white blood cells (WBC) graft was 12 days (range, 10-17 days) and the PLT graft was 15 days (range, 10-30 days), whereas for the patients in the TPO group, the median time to WBC and PLT graft was 12 days (range, 9-23 days) and 15.5 days (range, 9-41 days), respectively. In the first month after HSCT, the median WBC count in the eltrombopag group was 4.41 × 109/L (range, 0.87-40.01 × 109/L) and the median PLT was 89x109/L (range, 30-401 × 109/L); the median WBC and PLT \counts in the TPO group were 4.65 × 109/L (range, 0.99-23.63 × 109/L) and 86 × 109/L (range, 5-512 × 109/L), respectively. Patients in the TPO or eltrombopag group did not experience serious side effects after drug administration, and the difference in side effects on liver and kidney function between the two groups was not statistically significant.

Conclusion

Eltrombopag is safe and similarly promotes platelet engraftment to thrombopoietin after allogeneic HSCT.

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.

The problem of immune thrombocytopenia refractory to both eltrombopag and romiplostim

Immune thrombocytopenia refractory to multiple thrombopoietin receptor agonists remains a challenging clinical problem. This commentary discusses and contextualizes the recent report on this entity from Moulis and colleagues, and how to move forward with these patients. Commentary on: Moulis et al. Difficult-to-treat primary immune thrombocytopenia in adults: Prevalence and burden. Results from the CARMEN-France Registry. Br J Haematol 2024;204:1476-1482.

Eltrombopag improves platelet engraftment after haploidentical bone marrow transplantation: Results of a Phase II study

Slow platelet recovery frequently occurs after haploidentical hematopoietic stem cell transplantation (haplo-HSCT) with bone marrow graft and post-transplant cyclophosphamide (PCy)-based graft-versus-host disease (GVHD) prophylaxis. Improved platelet recovery may reduce the need for transfusions and improve outcomes. We investigated the safety and efficacy of eltrombopag, a thrombopoietin receptor agonist, at enhancing platelet recovery post-haplo-HSCT. The prospective study included patients ≥18 years of age who received haplo-HSCT with bone marrow graft and PCy. Patients received eltrombopag 300 mg/day starting on Day +5. The primary objective was to estimate platelet engraftment (>50 000/μL by Day 60). In a post hoc analysis, they were compared to a contemporary matched control group who did not receive eltrombopag. One hundred ten patients were included in the analysis (30 eltrombopag and 80 control). Seventy-three percent and 50% of patients in the eltrombopag group and control group, respectively, attained >50 000/μL platelet count by Day 60 (p = .043). No eltrombopag-related grade ≥4 adverse events were observed. Median time to platelet recovery (>20 000/μL) was 29 days with eltrombopag and 31 days for controls (p = .022), while its cumulative incidence was 90% (95% confidence interval [CI]: 78%-100%) with eltrombopag versus 67.5% (95% CI: 57%-78%) for controls (p = .014). Number of platelet transfusions received, overall survival, progression-free survival, GVHD rate, relapse rate, and non-relapse mortality were similar between groups. Overall, eltrombopag is safe and improves platelet recovery in patients undergoing haplo-HSCT with bone marrow graft and PCy.

Bioprinting Soft 3D Models of Hematopoiesis using Natural Silk Fibroin-Based Bioink Efficiently Supports Platelet Differentiation

Hematopoietic stem and progenitor cells (HSPCs) continuously generate platelets throughout one's life. Inherited Platelet Disorders affect ≈ 3 million individuals worldwide and are characterized by defects in platelet formation or function. A critical challenge in the identification of these diseases lies in the absence of models that facilitate the study of hematopoiesis ex vivo. Here, a silk fibroin-based bioink is developed and designed for 3D bioprinting. This bioink replicates a soft and biomimetic environment, enabling the controlled differentiation of HSPCs into platelets. The formulation consisting of silk fibroin, gelatin, and alginate is fine-tuned to obtain a viscoelastic, shear-thinning, thixotropic bioink with the remarkable ability to rapidly recover after bioprinting and provide structural integrity and mechanical stability over long-term culture. Optical transparency allowed for high-resolution imaging of platelet generation, while the incorporation of enzymatic sensors allowed quantitative analysis of glycolytic metabolism during differentiation that is represented through measurable color changes. Bioprinting patient samples revealed a decrease in metabolic activity and platelet production in Inherited Platelet Disorders. These discoveries are instrumental in establishing reference ranges for classification and automating the assessment of treatment responses. This model has far-reaching implications for application in the research of blood-related diseases, prioritizing drug development strategies, and tailoring personalized therapies.

Efficacy, Safety, and Population Pharmacokinetics of Eltrombopag in Children with Different Severities of Aplastic Anemia

Eltrombopag was approved as a first-line treatment for patients older than 2 years old with severe aplastic anemia (SAA). However, data on eltrombopag in children with different types of aplastic anemia (AA), especially non-severe AA (NSAA), are limited. We performed a prospective, single-arm, and observational study to investigate eltrombopag's efficacy, safety, and pharmacokinetics in children with NSAA, SAA, and very severe AA (VSAA). The efficacy and safety were assessed every 3 months. The population pharmacokinetic (PPK) model was used to depict the pharmacokinetic profile of eltrombopag. Twenty-three AA children with an average age of 7.9 (range of 3.0-14.0) years were enrolled. The response (complete and partial response) rate was 12.5%, 50.0%, and 100.0% after 3, 6, and 12 months in patients with NSAA. For patients with SAA and VSAA, these response rates were 46.7%, 61.5%, and 87.5%. Hepatotoxicity occurred in one patient. Fifty-three blood samples were used to build the PPK model. Body weight was the only covariate for apparent clearance (CL/F) and volume of distribution. The allele-T carrier of adenosine triphosphate-binding cassette transporter G2 was found to increase eltrombopag's clearance. However, when normalized by weight, the clearance between the wild-type and variant showed no statistical difference. In patients with response, children with NSAA exhibited lower area under the curve from time zero to infinity, higher CL/F, and higher weight-adjusted CL/F than those with SAA or VSAA. However, the differences were not statistically significant. The results may support further individualized treatment of eltrombopag in children with AA.

Treatment of refractory/relapsed Diamond-Blackfan anaemia with eltrombopag

Diamond-Blackfan anaemia (DBA) is a rare, inherited bone marrow failure syndrome with a ribosomal defect causing slowed globin chain production with normal haem synthesis, causing an overabundance of reactive iron/haem and erythroid-specific cellular toxicity. Eltrombopag, a non-peptide thrombopoietin receptor agonist, is a potent intracellular iron chelator and induced a robust durable response in an RPS19-mutated DBA patient on another trial. We hypothesized eltrombopag would improve RBC production in DBA patients. We conducted a single-centre, single-arm pilot study (NCT04269889) assessing safety and erythroid response of 6 months of daily, fixed-dose eltrombopag for DBA patients. Fifteen transfusion-dependent (every 3-5 weeks) patients (median age 18 [range 2-56]) were treated. One responder had sustained haemoglobin improvement and >50% reduction in RBC transfusion frequency. Of note, 7/15 (41%) patients required dose reductions or sustained discontinuation of eltrombopag due to asymptomatic thrombocytosis. Despite the low response rate, eltrombopag has now improved erythropoiesis in several patients with DBA with a favourable safety profile. Dosing restrictions due to thrombocytosis may cause insufficient iron chelation to decrease haem production and improve anaemia in most patients. Future work will focus on erythropoiesis dynamics in patients and use of haem synthesis inhibitors without an impact on other haematopoietic lineages.

Immune checkpoint inhibitor-related acquired amegakaryocytosis thrombocytopenia: a case report and literature review

Introduction

Immune checkpoint inhibitors (ICIs) are used in several advanced malignancies and may cause various immune-related adverse events (irAEs). Among them, hematological irAEs are less described. Acquired amegakaryocytic thrombocytopenia (AAT) is a rare immune hematologic disorder characterized by severe thrombocytopenia and complete absence of megakaryocytes in bone marrow.

Case presentation

Herein, we present the case of a patient in their 40s with metastatic melanoma who developed an AAT after 12 cycles of nivolumab (anti-PD1). His platelet count decreased by ≤5 × 109/l without other cytopenia. Bone marrow biopsy showed normal cellularity with a complete absence of megakaryocyte and T-CD8+ lymphocyte infiltration. Given the failure of systemic steroids, eltrombopag was started, an oral thrombopoietin receptor agonist (TPO-RA), and his platelet count subsequently increased with complete response.

Discussion

Four other cases are described on literature with the same features than non-ICI-related AAT. All cases occurred after anti-PD/PD-L1 treatment with a median onset of 5 weeks. The presentation of our case is quite different with delayed cytopenia. Both ciclosporin and TPO-RA seem to be efficient therapies.

Conclusion

TPO-RA could be preferred in oncologic patients, but safety data are still missing to define clear guidelines for immune-related AAT management.

Effectiveness and safety of eltrombopag in connective tissue disease patients with refractory immune thrombocytopenia: a retrospective study

Objectives

We aimed to investigate the safety and effectiveness of eltrombopag for adult patients with refractory immune thrombocytopenia (ITP) secondary to connective tissue disease (CTD).

Methods

This is a single-centre, retrospective cohort and propensity score-matched study. Data from CTD-ITP patients treated with eltrombopag between January 2019 and January 2023 were retrospectively analysed. Baseline characteristics and follow-up information were recorded. CTD patients without ITP were matched to identify the risk factors associated with CTD-ITP performed by Logistic regression analysis.

Results

Twenty patients were enrolled, including 5 systemic lupus erythematosus (SLE), 9 Sjögren's syndrome (SS) and 6 undifferentiated connective tissue disease (UCTD). Nineteen (95%) patients were female, and the median age was 59 years. Logistic regression analysis showed that anaemia (OR = 8.832, P = 0.007) was associated with increased risk of ITP, while non-erosive arthritis (OR = 0.045, P = 0.001) and interstitial lung disease (OR = 0.075, P = 0.031) were associated with reduced risk. Fourteen patients (70%) achieved a complete response (CR) and one (5%) achieved a partial response (PR). The median response time was 14 days. The median platelet count was 8.5 × 109/l at baseline of eltrombopag and increased to 122 × 109/l after 4 weeks. No adverse events were observed.

Conclusions

Eltrombopag appears to be effective, safe and well-tolerated in refractory ITP patients with CTD; larger studies are needed to confirm the generalizability of these findings.

Real-world use of thrombopoietin receptor agonists for the management of immune thrombocytopenia in adult patients in the United Kingdom: Results from the TRAIT study

Few studies have reported the real-world use of both romiplostim and eltrombopag in immune thrombocytopenia (ITP). TRAIT was a retrospective observational study aimed to evaluate the platelet responses and adverse effects associated with the use of these thrombopoietin receptor agonists (TPO-RAs) in adult patients with ITP in the United Kingdom. Of 267 patients (median age at diagnosis, 48 years) with ITP (primary ITP [n = 218], secondary ITP [n = 49]) included in the study, 112 (42%) received eltrombopag and 155 (58%) received romiplostim as the first prescribed TPO-RA. A platelet count ≥30 × 109 /L was achieved in 89% of patients with the first TPO-RA treatments, while 68% achieved a platelet count ≥100 × 109 /L. Treatment-free response (TFR; platelet count ≥30 × 109 /L, 3 months after discontinuing treatment) was achieved by 18% of the total patients. Overall, 61 patients (23%) switched TPO-RAs, most of whom achieved platelet counts ≥30 × 109 /L with the second TPO-RA (23/25 who switched from eltrombopag to romiplostim [92%]; 28/36 who switched from romiplostim to eltrombopag [78%]). TFR was associated with secondary ITP, early TPO-RA initiation after diagnosis, the presence of comorbidity and no prior splenectomy or treatment with steroids or mycophenolate mofetil. Both TPO-RAs had similar efficacy and safety profiles to those reported in clinical studies.

Real-world outcomes with immunosuppressive therapy for aplastic anemia in patients treated at the University of Michigan

Aplastic anemia (AA) is a rare bone marrow failure disorder that is treated with either allogeneic stem cell transplant or immunosuppressive therapy (IST) consisting of antithymocyte globulin (ATG), cyclosporine (CSA), and eltrombopag. While outcomes are favorable in younger patients, older patients (>60) have significantly worse long-term survival. The dose of ATG is often reduced in older patients and those with multiple comorbidities given concerns for tolerability. The efficacy and safety of dose-attenuated IST in this population is largely undescribed. We performed a retrospective review of patients with AA treated with IST. Our analysis was confounded by changes in practice patterns and the introduction of eltrombopag. We identified 53 patients >60 years old, of which, 20 received dose-attenuated IST, with no statistically significant difference in overall survival between full and attenuated dose cohorts. Overall response rates in both cohorts were similar at 6 months at 71% and 68%. There were more documented infectious complications in the full dose cohort (13 vs. 3). This supports the consideration of dose-attenuated IST in older patients with concerns about tolerance of IST. Lastly, our data confirmed favorable outcomes of younger patients receiving IST, especially in combination with eltrombopag.

Long-term eltrombopag in children with chronic immune thrombocytopenia: A single-centre extended real-life observational study in China

We have previously confirmed the efficacy and safety of eltrombopag (ELT) in children with chronic immune thrombocytopenia (cITP). However, data on both long-term exposure and early use of TPO-RAs are lacking, so further 'field-practice' evidence on treatment is required. Here, we report the long-term follow-up results (between September 2018 and June 2023) of our previous study. The main objective of this study was to retrospectively review our large institutional experience with ITP patients previously enrolled in our paediatric cITP study. We had more than 3 years of follow-up by June 2023 for treatment patterns and outcomes. A total of 65 patients (28 males) were enrolled, with a median age at ELT initiation of 6.34 (range 1.65, 14.13) years and a follow-up of 47.07 (36.00, 57.00) months, with 40.36 (10.53, 56.83) months of ELT therapy at the time of analysis. In total, 29.23% (19/65) of patients discontinued ELT due to stable response, and 18.46% (12/65) of patients switched to other ITP therapies due to loss of response (LOR) after 19.13 (14.53, 26.37) months. Of the 19 patients who discontinued ELT due to a stable response, 24.62% (16/65) achieved a 12 m sustained response off-treatment (SRoT); the last recorded platelet count ranged from 56 to 166 × 109 /L (median 107 × 109/L); and 4.62% (3/65) patients relapsed at 5, 6 and 9 months after discontinuation. Of the 12 patients who LOR to ELT after 19.13 (14.53, 26.37) months of therapy, four switched to avatrombopag, three switched to hetrombopag, two switched to traditional Chinese medicine (TCM), one underwent splenectomy and two received additional prednisolone under ELT treatment. Thirty-four patients who tapered and maintained a durable response. The patients with LOR and the patients with tapering were compared; the platelet count at the start of ELT is lower, and the time to response is longer in the patients with LOR. The platelet count at the start of ELT and the time to response may be the predictive factors for LOR during ELT treatment. We report more than 3 years of long-term clinical data on children with cITP using ELT. These data do not raise any new safety concerns regarding the long-term use of ELT in children with cITP.

Plain language summary of RACE study results: addition of eltrombopag to standard treatment of severe aplastic anemia

WHAT IS THIS SUMMARY ABOUT?

Severe aplastic anemia (SAA) and very severe aplastic anemia (vSAA) are blood diseases of the bone marrow. If a suitable donor for bone marrow transplant as initial treatment is unavailable, standard immunosuppression is used. Standard immunosuppression treatment includes horse antithymocyte globulin (hATG) and cyclosporin A (CsA). This summary investigated the results of standard immunosuppression treatment (Group A) versus standard immunosuppression treatment with a medication called eltrombopag (Group B) in participants with SAA and vSAA. Eltrombopag is a medicine that improves the blood platelet level and is taken by mouth (orally).

WHAT WERE THE RESULTS OF THE STUDY?

Compared to Group A, more participants in Group B showed increased blood cell level to a normal range without SAA or vSAA and faster treatment response. Side effects were similar in both groups even with the addition of eltrombopag for Group B. Participants in both groups reported feeling well after 6, 12 and 24 months. Differences in the participant-reported scores (overall health, physical, emotional, and social) between Group A and Group B were minimal.

WHAT DO THE RESULTS OF THE STUDY MEAN?

Immunosuppression treatment (hATG plus CsA) with eltrombopag benefited participants with SAA and vSAA and could be the new standard for SAA in persons who cannot undergo bone marrow transplant. At this time, eltrombopag is only approved in specific countries to treat the condition under study that is discussed in this summary. Clinical Trial Registration: NCT02099747 (RACE study).

Role of thrombopoietin receptor agonists in chemotherapy-induced thrombocytopenia: A meta-analysis

INTRODUCTION

Chemotherapy-induced thrombocytopenia (CIT) is a significant challenge in cancer treatment, often leading to dose reductions and reduced number of cycles. The limited effectiveness of platelet transfusions in managing CIT highlights the need for alternative treatments. Thrombopoietin receptor agonists (TPO-RA), including romiplostim, eltrombopag and avatrombopag, have shown potential in increasing platelet counts in CIT patients, necessitating a comprehensive analysis of their efficacy.

METHODS

This meta-analysis followed the Preferred Reporting Items for Systemic Reviews and Meta-analysis guidelines, searching Ovid databases up to 5 October 2023. The primary metric of interest was platelet count changes post-TPO-RA administration in CIT patients.

RESULTS

From the initial 867 studies obtained, 7 studies were selected based on the inclusion criteria. The analysis included 348 patients. A significant association was found between TPO-RA administration and platelet count increase, with a combined-effect increase of 69.52 ± 2.24 × 109/l. Subgroup analysis based on Romiplostim use suggested an increase of approximately 70.11 ± 39.07 × 109/l, while non-Romiplostim TPO-RAs showcased an increase of about 68.09 ± 82.58 × 109/l.

CONCLUSIONS

The meta-analysis demonstrates the effectiveness of TPO-RAs in managing CIT. Further research comparing platelet increases across standardised TPO-RA regimens is recommended to refine treatment strategies. This analysis provides valuable insights for clinicians in tailoring CIT treatment using TPO-RAs.

Thrombopoietin-receptor agonists for adult patients with immune thrombocytopenia: a narrative review and an approach for managing patients fasting intermittently

Introduction

Thrombopoietin-receptor agonist (TPO-RAs) currently represent the state of art for treating immune thrombocytopenia. Their different molecular structures contribute to the difference in their pharmacodynamics and pharmacokinetics. This narrative review aims to provide an overview of the current TPO-RAs approved for primary immune thrombocytopenia (romiplostim, eltrombopag, avatrombopag) and the effect of intermittent fasting in adult patients receiving TPO-RAs.

Areas covered

Literature was searched with no limits on date or language, using various combinations of keywords. Data on the pharmacokinetics, pharmacodynamics, efficacy, and safety of TPO-RAs and the effect of intermittent fasting were summarized.

Expert opinion

Switching between TPO-RAs is a useful strategy to tackle some associated limitations. Romiplostim and avatrombopag have an advantage over eltrombopag as they do not require any dietary restrictions. In cases where romiplostim and avatrombopag are unavailable, patients should be educated on the appropriate administration, possible interactions, and dietary restrictions before initiating eltrombopag.

Pediatric immune thrombocytopenia: a focus on eltrombopag as second-line therapy

BACKGROUND

Immune thrombocytopenia (ITP) is the most common acquired bleeding disorder. In both children and adults, the primary goal of any therapeutic approach consists of cessation of bleeding and its prevention. Several options are currently available for first-line therapy in Europe, including corticosteroids and intravenous immunoglobulin (IVIg) infusion, which has a similar efficacy and safety profile in both the pediatric and adult populations. When second-line therapy is needed in the pediatric setting, current guidelines recommend eltrombopag as the drug of choice.

PROCEDURE

The aim of this article is to summarize the available evidence and present real-life experience on eltrombopag as second-line therapy in pediatric patients with ITP, with a focus on dosing and response to therapy as well as its tapering and discontinuation.

RESULTS

In our setting, eltrombopag is associated with good safety profile as well as promising efficacy; dose de-escalation was feasible in 94% of cases and often reached very low pro/kg dosage, with full discontinuation in 15% of cases. In daily practice, a standardized approach for discontinuation of eltrombopag in pediatric patients with ITP is still lacking. Herein, an easy-to-use scheme for tapering and discontinuation in candidate pediatric patients is proposed that proposes 25% dose reduction every four weeks.

CONCLUSIONS

In future management of pediatric ITP patients, it will be crucial to assess if thrombopoietin receptor agonists might be more effective in earlier phases of the disease and can modify the course of the disease.

Analysis of clinical characteristics and treatment efficacy in two pediatric cases of ANKRD26-related thrombocytopenia

ANKRD26-related thrombocytopenia (ANKRD26-RT or THC2, MIM 188 000), an autosomal dominant thrombocytopenia, is unresponsive to immunosuppressive therapy and susceptible to hematological malignancies. A large number of pediatric patients are diagnosed with immune thrombocytopenia (ITP) every year; however, thrombocytopenia of genetic origin is often missed. Extensive characterization of ANKRD26-RT will help prevent missed diagnosis and misdiagnosis. Furthermore, identification of ANKRD26-RT will help in the formulation of an accurate diagnosis and a treatment plan. In our study, we report cases of two Chinese pediatric patients with ANKRD26-RT and analyze their clinical characteristics, gene mutations, and treatment modalities. Both patients were 1-year-old and presented with mild bleeding (World Health Organization(WHO) score grade 1), different degrees of platelet reduction, normal mean platelet volume, and megakaryocyte maturation impairment not obvious. Genetic tests revealed that both patients had ANKRD26 gene mutations.Patient 1 had a mutation c.-140C>G of the 5' untranslated region (UTR), and patient 2 had a mutation of c.-127A>T of 5'UTR. Both patients were treated with eltrombopag, and the treatment was no response, with no adverse reactions.

The efficacy and safety of eltrombopag in treating TKI-induced thrombocytopenia in patients with chronic myeloid leukemia

ABSTRACTThrombocytopenia is one of the most common hematological adverse reactions in chronic myeloid leukemia (CML) patients receiving tyrosine kinase inhibitors (TKI) therapy, causing life-threatening bleeding cases. However, there are fewer therapeutic drugs for TKI-induced thrombocytopenia. Eltrombopag is a non-peptide thrombopoietin receptor agonist used for the treatment of immune thrombocytopenia， aplastic anemia, and hepatitis C-associated thrombocytopenia. Nevertheless, studies of eltrombopag for TKI-induced thrombocytopenia are still lacking. This study retrospectively analyzed the clinical and test data of 21 CML patients with TKI-related thrombocytopenia. The results demonstrated that the median baseline value of thrombocytopenia in the 21 CML patients was 15.57 × 109/L [2-28 × 109/L]. Following treatment with eltrombopag, 16 patients had a significant increase in their platelet levels. The peak median for platelet increase in effective responders was 145.12 × 109/L (51-460 × 109/L). However, 5 patients failed to respond to eltrombopag. Moreover, 4 of the 21 patients enrolled had adverse reactions, including reversible liver function impairment, palpitation, headache, insomnia, and loss of appetite. Nonetheless, no cases of disease progression, thrombotic events, or myelofibrosis were observed. Hence, eltrombopag may be a useful adjunctive therapy for relieving TKI-related thrombocytopenia in patients with CML.

Treatment of immune thrombocytopenia during pregnancy with thrombopoietin receptor agonists

The introduction of thrombopoietin receptor agonists (TPO-RAs) led to a paradigm shift in the management of immune thrombocytopenia (ITP). However, TPO-RAs are not approved for use during pregnancy due to the absence of evidence and concerns for possible effects on the fetus due to their expected transplacental transfer. This comprehensive review examines the safety and efficacy of TPO-RA in 45 pregnancies of women with ITP (romiplostim n = 22; eltrombopag n = 21; both in the same pregnancy n = 2). Mothers experienced failure of the median of three treatment lines during pregnancy prior to TPO-RA administration. A platelet response (>30 × 109 /L) was seen in 86.7% of cases (including a complete response >100 × 109 /L in 66.7%) and was similar between eltrombopag and romiplostim (87.0% and 83.3%, p = 0.99). The maternal safety profile was favourable, with no thromboembolic events encountered. Neonatal thrombocytopenia was noted in one third of cases, with one case of ICH grade 3, and neonatal thrombocytosis was observed in three cases. No other neonatal adverse events attributable to TPO-RAs were seen. This review suggests that the use of TPO-RA during pregnancy is associated with a high response rate and appears safe. Nevertheless, TPO-RA should not be routinely used in pregnancy and should be avoided in the first trimester until further evidence is accumulated.

A De Novo Frameshift Mutation in RPL5 with Classical Phenotype Abnormalities and Worsening Anemia Diagnosed in a Young Adult-A Case Report and Review of the Literature

Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome associated with malformations. DBA is related to defective ribosome biogenesis, which impairs erythropoiesis, causing hyporegenerative macrocytic anemia. The disease has an autosomal dominant inheritance and is commonly diagnosed in the first year of life, requiring continuous treatment. We present the case of a young woman who, at the age of 21, developed severe symptomatic anemia. Although, due to malformations, a congenital syndrome had been suspected since birth, a confirmation diagnosis was not made until the patient was referred to our center for an evaluation of her anemia. In her neonatal medical history, she presented with anemia that required red blood cell transfusions, but afterwards remained with a stable, mild, asymptomatic anemia throughout her childhood and adolescence. Her family history was otherwise unremarkable. To explain the symptomatic anemia, vitamin deficiencies, autoimmune diseases, bleeding causes, and myeloid and lymphoid neoplasms were investigated and ruled out. A molecular investigation showed the RPL5 gene variant c.392dup, p.(Asn131Lysfs*6), confirming the diagnosis of DBA. All family members have normal blood values and none harbored the mutation. Here, we will discuss the unusual evolution of this case and revisit the literature.

Comparison of eltrombopag and avatrombopag in the treatment of refractory/relapsed aplastic anemia: a single-center retrospective study in China

Background

Eltrombopag (ELT), a thrombopoietin receptor agonist (TPO-RA), has been approved for relapsed/refractory aplastic anemia (AA). However, data on avatrombopag (AVA), another TPO-RA, are limited, and the comparisons between the two TPO-RAs are lacking.

Objectives

We aimed to compare the efficacy and safety between ELT and AVA in relapsed/refractory AA patients.

Design

In this retrospective study, patients with relapsed/refractory AA who had been treated with ELT (N = 45) or AVA (N = 30) alone and had compatible baseline hematological parameters were compared.

Methods

Data from patients diagnosed with acquired AA were retrospectively collected. All patients were refractory/relapsed to standard immunosuppressive therapy (IST) for at least 6 months before ELT or AVA. Patients had to be treated with ELT or AVA alone for at least 6 months before evaluation if they did not respond. Baseline characteristics, overall response (OR), complete response (CR), relapse, adverse events, and factors that may affect efficacy were analyzed.

Results

Of the 75 patients enrolled, 45 received ELT and 30 received AVA. Patients with AVA had a higher percentage of abnormal liver or renal function than those with ELT (p = 0.036). No significant difference was found in the OR/CR rate in the first/second/third/sixth month between the two cohorts (p > 0.05). Patients treated with AVA had a shorter median time to response than those treated with ELT (p = 0.012) and had a higher platelet level in the second month (p = 0.041). AVA had fewer adverse events than ELT (p = 0.046). Under compatible follow-up time (p = 0.463), no difference was found between the ELT and AVA cohorts in relapse (p = 1.000) or clone evolution (p = 0.637). No predictive factors for OR and CR in the sixth month were found for either ELT or AVA.

Conclusion

With worse liver or renal function, AVA had a similar OR/CR rate but a shorter median time to response and fewer adverse events for patients with relapsed/refractory AA.

Eltrombopag for the Treatment of Allogeneic Hematopoietic Stem Cell Transplantation-Related Poor Graft Function

INTRODUCTION

Allogeneic stem cell transplantation (ASCT) is a crucial therapeutic strategy for hematological and non-hematological disorders. Poor graft function (PGF) after ASCT presents a critical challenge that does not have a standardized treatment approach. A thrombopoietin-mimetic oral drug eltrombopag shows promise in some bone failure syndromes. This study aimed to analyze the efficacy of eltrombopag in treating PGF after ASCT.

METHODS

Patients receiving eltrombopag for PGF after ASCT between 2017 and 2020 were retrospectively evaluated. Patients' characteristics, details for ASCT, timing, treatment, and possible contributors for PGF, response to eltrombopag treatment, and overall response rate (ORR) were analyzed.  Results: Eighteen patients were assessed. Eltrombopag treatment yielded a favorable response in 11 patients, resulting in an ORR of 61%. The ORR in secondary PGF was better than that in primary PGF (83% and 17% respectively). There was a marked enhancement in platelet and hemoglobin levels following eltrombopag treatment (p=0.001 and p=0.030, respectively), while neutrophil values exhibited no significant change (p=0.8). Among the responding patients, four individuals (22%) underwent a tapering and discontinuation of eltrombopag. No toxicity was observed above grade one, and no patient discontinued eltrombopag because of intolerability or adverse events.

CONCLUSION

Our findings affirm that eltrombopag can treat poor graft function after allogeneic stem cell transplantation without significant toxicities. These results contribute to the growing body of evidence supporting the use of eltrombopag in poor graft function after allogeneic stem cell transplantation, providing insights into its potential benefits and limitations.

Therapeutic Outcomes of High Dose-Dexamethasone versus Prednisolone + Azathioprine, Rituximab, Eltrombopag, and Romiplostim Strategies in Persistent, Chronic, Refractory, and Relapsed Immune Thrombocytopenia Patients

BACKGROUND

Primary immune thrombocytopenia (ITP) is an inflammatory autoimmune disease that can be managed with several treatment options. However, there is a lack of comparative data on the efficacy of these options in different phases of the disease.

AIM OF THE STUDY

This study aimed to evaluate the efficacy of high-dose Dexamethasone (HD-DXM), Prednisolone + Azathioprine, Rituximab, Eltrombopag, and Romiplostim schedules in persistent, chronic refractory or relapsed Egyptian ITP patients with a platelet count ≤30 × 109/L. The primary outcome measure was a sustained increase in platelet counts over 50 × 109/L for an additional 12 months without additional ITP regimens. The study also aimed to identify a suitable treatment regimen with a long remission duration for each phase of ITP.

RESULTS

Prednisolone + Azathioprine was significantly more effective in achieving an overall response in persistent patients than Romiplostim, high-dose Dexamethasone, and Rituximab. (90.9% vs. 66.6, [Odds ratio, OR: 5; confidence interval, CI 95% (0.866-28.86)], 45%, [OR: 0.082, CI 95% (0.015-0.448)] and, 25%, [OR: 30, CI 95% (4.24-211.8)], respectively, p-value < 0.01). Eltrombopag was significantly more effective in achieving a durable response in refractory ITP than HD-DXM, Rituximab, and Prednisolone; (80% compared to 32.2% [OR: 0.119, CI 95% (0.035-0.410)], 22.2% [OR:0.071, CI 95% (0.011-0.455)], and 18.1% [OR: 0.056, CI 95% (0.009-0.342)], respectively, p-value < 0.01).

CONCLUSIONS

Finally, Eltrombopag following HD-DXM showed the highest percentage of patients with complete treatment-free survival times of at least 330 days. These findings could help clinicians choose the most appropriate treatment for their patients with ITP based on the phase of the disease. This trial is registered in clinicaltrials.gov with registration number NCT05861297.

Safety of non‑peptide thrombopoietin receptor agonists in patients with immune thrombocytopenia: A systematic review and meta‑analysis of short‑term double‑blind randomized clinical trials

The aim of the present study was to analyze the safety of non-peptide thrombopoietin receptor agonists (TPO-RAs) for immune thrombocytopenia (ITP) treatment. All studies reporting adverse events (AEs) in relation to ITP treatment with eltrombopag, avatrombopag, and hetrombopag were retrieved from PubMed, Web of Science, and Embase databases. RevMan 5.4.1 was used for meta-analysis, heterogeneity and bias analyses. A total of 1,078 patients from seven eligible studies were enrolled. In the enrolled clinical trials, the double-blind period was between 6 weeks and 6 months. The results revealed that the chances of any AEs [relative risk (RR)=1.16; 95% confidence interval (CI), 0.90-1.51; I²=78%; P=0.26], grade 3/4 AEs (RR=1.07; 95% CI, 0.63-1.80; I²=0%; P=0.81), elevated transaminase levels (RR=1.09; 95% CI, 0.68-1.74; I²=0%; P=0.72), thrombosis (RR=1.92; 95% CI, 0.55-6.66; I²=0%; P=0.31) and cataracts (RR=0.83; 95% CI, 0.38-1.83; I²=0%; P=0.65) were not significantly higher in patients with ITP that received non-peptide TPO-RAs compared with patients with ITP treated with a placebo. The present study indicated that non-peptide TPO-RAs were relatively safe for patients with ITP, at least within 6 months of administration.

Long term use of eltrombopag in children with chronic immune thrombocytopenia: extended real life retrospective multicenter experience of the Italian Association of Pediatric Hematology and Oncology

Background

The present multicenter retrospective study on eltrombopag administration in Italian children with chronic ITP aims to extend follow-up of our previous study.

Materials and methods

This retrospective multicenter study was conducted in 17 centers affiliated to the Italian Association of Pediatric Hematology and Oncology (AIEOP). Patients were classified into three subgroups: group 1 included patients who discontinued treatment due to a stable platelet count; group 2 included patients who discontinued treatment due to ineffectiveness; group 3 included patients who did not permanently discontinue treatment.

Results

56 patients were eligible for analysis. The median duration of eltrombopag treatment was 40 months (7-71 months). Twenty patients (36%) discontinued permanently eltrombopag. The reasons of permanent discontinuation were adverse effects (n = 1), inefficacy (n = 10), stable platelet count (n = 9). All patients of group 1 maintained a durable response without additional treatments after eltrombopag discontinuation. We found that patients of group 2 were on treatment for less time (median treatment time: 13.5 months, min: 6.0 - max: 56.0) than patients of group 1 (median treatment time: 34 months, min: 16.0 - max: 62.0) (p < 0.05). Patients of group 2 mostly did not achieve a stable platelet count in the first 6 months of treatment and underwent concomitant therapies during follow-up respect of group 1 and group 3 (p < 0.01).

Conclusion

Our study found that the benefits of eltrombopag treatment, in terms of platelet count improvement and use of additional therapies, are identifiable from the first 6 months of treatment.

Eltrombopag plus cyclosporine in refractory immune thrombocytopenia: a single-center study

Background

With the development of thrombopoietin receptor agonists, the prognosis of immune thrombocytopenia (ITP) in patients in whom there was a poor response to first-line treatment has greatly improved. However, there are still some patients who are refractory to eltrombopag.

Objectives

To explore the efficacy and safety of eltrombopag combined with low-dose cyclosporine in the management of patients with refractory ITP.

Methods

A total of 21 participants with ITP who failed to respond to multiple lines of therapy (including a daily dose of 75 mg of eltrombopag for at least 30 days) treated at The First Affiliated Hospital of Zhejiang Chinese Medical University between January 2018 and August 2022 were included. All enrolled patients subsequently received 50 mg of eltrombopag daily and low-dose cyclosporine (3 mg/kg/d, with an initial target concentration of 75-120 ng/mL). The efficacy and safety of the combined therapies were evaluated.

Results

A total of 76.2% (16/21) of the patients responded to the combination of cyclosporine and eltrombopag, with a median time to response of 14.5 (range, 5-37) days. A complete response (platelet count ≥ 100 × 10⁹/L) was observed in 81.3% (13/16) of the patients, among whom 1 patient experienced relapse due to self-reduction in eltrombopag. During a median follow-up of 180 days, there were no relapses, and 70% (7/10) of the patients successfully stopped or decreased concomitant ITP medications. One patient had both a catheter-related deep vein thrombosis and a venous cerebral thrombotic event later; no other severe drug-related adverse events were observed.

Conclusion

Combining low-dose cyclosporine with eltrombopag may be an effective alternative for multirefractory ITP that is nonresponsive to eltrombopag alone.

Safety of romiplostim and eltrombopag for children with immune thrombocytopenia: a pharmacovigilance study of the FDA adverse event reporting system database

BACKGROUND

Romiplostim and eltrombopag are thrombopoietin receptor agonists (TPORAs) that have been approved by the FDA on 22 August 2008 and 20 November 2008 for pediatric immune thrombocytopenia (ITP). However, postmarketing pharmacovigilance of TPORAs in children still attracts much attention. We aimed to evaluate the safety of the TPORAs romiplostim and eltrombopag using data from the Adverse Event Reporting System database of FDA (FAERS).

RESEARCH DESIGN AND METHODS

We conducted a disproportionality analysis and analyzed data from the FAERS database to characterize the key features of adverse events (AEs) associated with TPO-RAs approved for children under 18 years of age.

RESULTS

Since their approval in the market in 2008, 250 and 298 reports of romiplostim and eltrombopag use in children have been published in the FAERS database, respectively. The most frequent AE associated with romiplostim and eltrombopag was epistaxis. Neutralizing antibodies and vitreous opacities showed the strongest signals for romiplostim and eltrombopag, respectively.

CONCLUSIONS

The labeled AEs for romiplostim and eltrombopag in children were analyzed. Unlabeled AEs may reflect the potential of new clinical individuals. Early recognition and management of AEs that appear in children treated with romiplostim and eltrombopag are of key importance in clinical practice.

The Outcomes and Adverse Drug Patterns of Immunomodulators and Thrombopoietin Receptor Agonists in Primary Immune Thrombocytopenia Egyptian Patients with Hemorrhage Comorbidity

Immune thrombocytopenia (ITP) treatment has evolved recently. However, none of the treatments have only benefits without drawbacks. This study aimed to compare the clinical outcomes and adverse drug patterns of Eltrombopag, Romiplostim, Prednisolone + Azathioprine, High Dose-dexamethasone (HD-DXM) (control group), and Rituximab in primary ITP Egyptian patients. All patients were initiated with corticosteroids, HD-DXM, as a first-line treatment for the first month immediately following diagnosis. Four hundred sixty-seven ITP patients were randomly assigned to five groups. The outcome measures were judged at baseline, at the end of treatment (6 months), and after an additional 6-month free treatment period. The follow-up period for which relapse is noted was 6 months after the end of treatment. Eltrombopag and Romiplostim resulted in a significantly higher incidence of sustained response than Rituximab, HD-DXM, and Prednisolone + Azathioprine (55.2% and 50.6% vs. 29.2%, 29.1%, and 18%, respectively; p-value < 0.001). More patients on immunomodulators (Prednisolone+ Azathioprine, HD-DXM, and Rituximab) relapsed than those on Romiplostim and Eltrombopag (81.9%, 70.8%, and 70.7% vs. 49.3%, and 44.7%, respectively; p-value < 0.01). We also describe 23 reports of pulmonary hypertension with Prednisolone+ Azathioprine and 13 reports with HD-DXM. The thrombotic events occurred in 16.6% and 13% of patients who received Eltrombopag and Romiplostim treatment, respectively. Most patients had at least one or two risk factors (92.8% of cases). Corticosteroids are effective first-line therapy in primary ITP patients. However, relapse is frequent. Eltrombopag and Romiplostim are safer and more effective than Prednisolone, HD-DXM, and Rituximab. They might be reasonable beneficial options after a one-month HD-DXM regimen.

A Case of Severe Aplastic Anemia in a 35-Year-Old Male With a Good Response to Immunosuppressive Therapy

Aplastic anemia (AA) is a severe but rare hematologic condition associated with hematopoietic failure leading to decreased or total absent hematopoietic precursor cells in the bone marrow. AA presents at any age with equal distribution among gender and race. There are three known mechanisms of AA: direct injuries, immune-mediated disease, and bone marrow failure. The most common etiology of AA is considered to be idiopathic. Patients usually present with non-specific findings, such as easy fatigability, dyspnea on exertion, pallor, and mucosal bleeding. The primary treatment of AA is to remove the offending agent. In patients in whom the reversible cause was not found, patient management depends on age, disease severity, and donor availability. Here, we present a case of a 35-year-old male who presented to the emergency room with profuse bleeding after a deep dental cleaning. He was found to have pancytopenia on his laboratory panel and had an excellent response to immunosuppressive therapy.

Outcomes of switching to avatrombopag following treatment failure with eltrombopag in paediatric immune thrombocytopenia: A real-world study in China

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia and a haemorrhagic risk. Thrombopoietin receptor agonists (TPO-RAs) are highly effective for ITP and are widely used to treat patients with steroid treatment failure or dependency. However, although treatment response to TPO-RAs may differ according to the type, the potential impact of switching from eltrombopag (ELT) to avatrombopag (AVA) with respect to efficacy or tolerance in children remains unknown. This study aimed to evaluate the outcomes of switching from ELT to AVA in paediatric patients with ITP. We retrospectively evaluated children with chronic immune thrombocytopenia (cITP) switched from ELT to AVA owing to treatment failure at the Hematology-Oncology Center of Beijing Children's Hospital between July 2021 and May 2022. Overall, 11 children (seven and four boys and girls respectively) with a median age of 8.3 (range: 3.8-15.3) years were included. The overall response and complete response (platelet [PLT] count ≥100 × 10⁹ /L) rates during AVA treatment were 81.8% (9/11) and 54.6% (6/11) respectively. The median PLT count was significantly increased from ELT to AVA (7 [range: 2-33] × 10⁹ /L vs. 74 [15-387] × 10⁹ /L; p = 0.007). The median time to PLT count ≥30 × 10⁹ /L was 18 (range: 3-120) days. Overall, 7/11 patients (63.6%) used concomitant medications, and concomitant medication use was gradually discontinued within 3-6 months after AVA initiation. In conclusion, AVA after ELT is effective in the heavily pretreated paediatric cITP population, with high response rates even in those with an inadequate response to a prior TPO-RA.

Sustained response off treatment in eltrombopag for children with persistent/chronic primary immune thrombocytopenia: A multicentre observational retrospective study in China

Eltrombopag (ELT) is effective and safe in adult persistent/chronic immune thrombocytopenia (p/cITP); a proportion could achieve a sustained response off treatment (SRoT); however, data on children are lacking. We attempted to analyse SRoT of ELT in children with p/cITP in this study. A multicentre retrospective observational study was performed in November 2022 for children with p/cITP who used ELT alone for >2 months between January 2017 and November 2021. Clinical data of pre-, during and post-ELT were collected. SRoT was defined as maintaining a platelet count of ≥30 × 10⁹ /L without rescue therapy for at least 6 months off ELT. There were 143 patients enrolled; 69.2% (99/143) achieved an overall response of 43.3% and 25.9% achieved complete response (CR) and response (R). Among the 35 patients analysed from whom ELT was withdrawn, 71.4% (25/35) showed SRoT after discontinuing ELT without additional ITP therapy, with a median follow-up of 0.94 (range, 0.53-3.8) years, equal to 17.5% (25/143) in all patients treated with ELT. Compared with the patients with relapse (n = 10), the SRoT patients (n = 25) had a higher rate of CR (80% [20/25] vs. 40% [4/10]), shorter interval time from initiation to taper (6.4 months vs. 9.4 months), longer time from taper to withdrawal (1.1 years vs. 0.3 years) and a longer duration of ELT treatment (1.6 years vs. 0.5 years) with p < 0.05. Patients who achieved CR could attain SRoT more easily (p = 0.02). ELT had a response in 69.2% of children with p/cITP and 17.5% of them attained SRoT with good tolerance. The patients who achieved CR and began ELT treatment as early as possible, with a longer treatment duration and slower tapering, had a higher probability of SRoT.

Current Concepts in the Diagnosis and Management of Adult Primary Immune Thrombocytopenia: Our Personal View

Primary immune thrombocytopenia (ITP) is an acquired blood disorder that causes a reduction in circulating platelets with the potential for bleeding. The incidence of ITP is slightly higher in adults and affects more women than men until 60 years, when males are more affected. Despite advances in basic science, primary ITP remains a diagnosis of exclusion. The disease is heterogeneous in its clinical behavior and response to treatment. This reflects the complex underlying pathophysiology, which remains ill-understood. Platelet destruction plays a role in thrombocytopenia, but underproduction is also a major contributing factor. Active ITP is a proinflammatory autoimmune disease involving abnormalities within the T and B regulatory cell compartments, along with several other immunological abnormalities. Over the last several years, there has been a shift from using immunosuppressive therapies for ITP towards approved treatments, such as thrombopoietin receptor agonists. The recent COVID-19 pandemic has hastened this management shift, with thrombopoietin receptor agonists becoming the predominant second-line treatment. A greater understanding of the underlying mechanisms has led to the development of several targeted therapies, some of which have been approved, with others still undergoing clinical development. Here we outline our view of the disease, including our opinion about the major diagnostic and therapeutic challenges. We also discuss our management of adult ITP and our placement of the various available therapies.

Emerging data on thrombopoietin receptor agonists for management of chemotherapy-induced thrombocytopenia

INTRODUCTION

Chemotherapy induced thrombocytopenia (CIT) is a common complication of cancer treatment, frequently leads to reduced relative dose intensity, and is associated with reduced survival. Given the lack of FDA-approved therapies for CIT, thrombopoietin receptor agonists (TPO-RAs) have received significant attention for treatment and prevention of CIT.

AREAS COVERED

This review will summarize the development of prior agents for treatment of CIT, discuss the existing literature investigating the use of TPO-RAs in CIT primarily in patients with solid tumor malignancies, and offer insights on the future direction of TPO-RAs and other therapeutics for CIT.

EXPERT OPINION

In alignment with NCCN guidelines, we recommend that patients with CIT participate in a clinical trial for consideration of TPO-RA treatment or consider off-label use of romiplostim when participation in clinical trials is not possible. The literature to date supports the use of TPO-RAs for treatment of persistent CIT. Further data is needed to describe the long-term efficacy, safety, and prescribing practices of TPO-RAs in a diverse patient population with a variety of tumor types and chemotherapy regimens in addition to exploring the underlying biology of CIT.

Sustained Remission Off-Treatment (SROT) of TPO-RAs: The Burgos Ten-Step Eltrombopag Tapering Scheme

Background and Objectives: TPO-RAs (romiplostim/eltrombopag/avatrombopag) have broadly demonstrated high efficacy rates (59-88%), durable responses (up to three years) and a satisfactory safety profile in clinical trials. The effect of TPO-RAs is classically considered to be transient because platelet numbers usually dropped rapidly to baseline unless therapy was maintained. However, several groups have reported the possibility of successfully discontinuing TPO-RAs in some patients without further need for concomitant treatments. This concept is usually referred as sustained remission off-treatment (SROT). Materials and Methods: Unfortunately, we still lack predictors of the response to discontinuation even after the numerous biological, clinical and in vitro studies performed to study this phenomenon. The frequency of successful discontinuation is matter of controversy, although a percentage in the range of 25-40% may probably be considered a consensus. Here, we describe all major routine clinical practice studies and reviews that report the current position on this topic and compare them with our own results in Burgos. Results: We report our Burgos ten-step eltrombopag tapering scheme with which we have achieved an elevated percentage rate of success (70.3%) in discontinuing treatment. Conclusions: We hope this protocol may help successfully taper and discontinue TPO-RAs in daily clinical practice.

Elucidation of DNA-Eltrombopag Binding: Electrochemical, Spectroscopic and Molecular Docking Techniques

Eltrombopag is a powerful adjuvant anticancer drug used in treating MS (myelodysplastic syndrome) and AML (acute myeloid leukemia) diseases. In this study, the interaction mechanism between eltrombopag and DNA was studied by voltammetry, spectroscopic techniques, and viscosity measurements. We developed a DNA-based biosensor and nano-biosensor using reduced graphene oxide-modified glassy carbon electrode to detect DNA-eltrombopag binding. The reduction of desoxyguanosine (dGuo) and desoxyadenosine (dAdo) oxidation signals in the presence of the drug demonstrated that a strong interaction could be established between the eltrombopag and dsDNA. The eltrombopag-DNA interaction was further investigated by UV absorption and fluorescence emission spectroscopy to gain more quantitative insight on binding. Viscosity measurements were utilized to characterize the binding mode of the drug. To shed light on the noncovalent interactions and binding mechanism of eltrombopag molecular docking and molecular dynamics (MD), simulations were performed. Through simultaneously carried out experimental and in silico studies, it was established that the eltrombopag binds onto the DNA via intercalation.

Catastrophic antiphospholipid syndrome in lupus-associated immune thrombocytopenia treated with eltrombopag A case series and literature review

BACKGROUND

Eltrombopag, a thrombopoietin receptor (TPO-R) agonist, is considered a second-line treatment for patients with refractory immune thrombocytopenia (ITP). Systemic lupus erythematosus (SLE) is frequently associated with ITP. In some cases, thrombocytopenia in SLE patients is attributed to concurrent antiphospholipid antibodies (APLA). Currently, data regarding treatment with TPO-R agonists for ITP in SLE or APLA patients are limited. The incidence of SLE flare or antiphospholipid syndrome while on TPO-R agonists has not been well-studied.

CASES

We report 2 cases of female patients with SLE and concurrent triple positive APLA, without thrombotic events in their medical history, in our rheumatology clinic, who were treated for refractory ITP with eltrombopag. Both developed catastrophic antiphospholipid syndrome a few weeks after beginning treatment with eltrombopag. They were admitted to the intensive care unit and treated with solumedrol, plasmapheresis, anticoagulation and rituximab.

CONCLUSIONS

We describe a severe possible side-effect of eltrombopag as a trigger of catastrophic antiphospholipid syndrome, a rare initial manifestation of antiphospholipid syndrome, in SLE patients with APLA. We suggest that APLA should be tested before initiating eltrombopag in patients with SLE-associated ITP. The safety of this treatment should be considered in these cases.

Molecular Docking Analysis of Adhatoda vasica with Thromboxane A2 Receptor (TXA2R) (6IIU) and Antiviral Molecules for Possible Dengue Complications

OBJECTIVE

The present study is an in silico model of platelet amplification potential of Adhatoda vasica, which can be used to treat thrombocytopenia in dengue complications.

METHODS

Docking studies have proved to be an essential tool that facilitates the structural diversity of natural products to be harnessed in an organized manner. In the present study, vasicine containing natural anti-dengue potential was subjected to docking studies using Schrodinger glides software (ver.11.1). The docking study was carried out to find out the potential molecular targets for selected protein. The docking was carried out on different ligands, like vasicine, ramatroban, chloroquine, celgosivir, and standard eltrombopag downloaded from PubChem and retrieved to glide software and ligands prepared using lig prep wizard. Docking was performed using the ligand docking wizard of Glide-maestro 2018.

RESULTS

The docking score of vasicine (-5.27) is nearly identical to the standard eltrombopag (-6.08), and both ligands bind with one hydrogen bond. The validation score of ramatroban is -12.39, binding with five hydrogen bonds, Celgosivir exhibited a docking score of -7.3 with three hydrogen bonds, and chloroquine displayed no hydrogen bond but had a docking score of -4.6.

CONCLUSION

Vasicine was found to be the most suitable target of platelet amplification potential from Adhatoda vasica. However, the molecular docking results are preliminary, and it has been indicated that vasicine could be one of the potential ligands to treat the thrombocytopenia of dengue; experimental evaluation will be carried out in the near future.

Platelet kinetics in patients with chronic immune thrombocytopaenia treated with thrombopoietin receptor agonists

INTRODUCTION

Thrombopoietin receptor agonists (TPO-RAs) increase platelet counts (PC) in the majority of patients with chronic immune thrombocytopaenia (ITP). Platelet kinetics study (PKS) might contribute to the understanding of mechanisms that lead to durable response.

OBJECTIVES

To evaluate the effects of TPO-RAs on PKS parameters in chronic ITP patients.

METHODS

Fifteen chronic ITP patients, aged 59 years [range: 22-84], female/male: 10/5, splenectomised 7/15, were treated with TPO-RAs (eltrombopag/romiplostim: 11/4). Durable response was defined as PC ≥30 × 10⁹ /L at 6 months. Autologous ¹¹¹ Indium-oxinate PKS was performed before and 5 months after TPO-RAs initiation. Accordingly, platelet survival (PS), platelet turnover, production ratio and sequestration site were assessed.

RESULTS

Durable response was achieved in 13/15 of patients (eltrombopag/romiplostim: 10/3). Pre-treatment parameters were: PC 10 × 10⁹ /L [range: 1-110], PS 0.5 days [range: 0.1-1.7 (normal values: 7-10)], platelet turnover 30 857 Plt/μL/day [range: 944-103 500] and platelet production ratio 0.64 [range: 0.01-3.2 (normal values: 1 ± 0.2)]. Post-treatment assessment showed significantly higher: PC 92.5 × 10⁹ /L [range: 28-260, p = .001], PS 2.2 days [range: 0.1-3.6, p = .008], platelet turnover 70 213 Plt/μL/day [range: 2800-462 236, p = .02] and platelet production ratio 1.8 [range: 0.5-37.9, p = .011] compared to the pre-treatment values. Platelet sequestration site altered in 3/15 treated with TPO-RAs.

CONCLUSIONS

TPO-RAs could increase PC by simultaneous increasing of platelet production and decreasing of platelet destruction.

The efficacy and the safety of eltrombopag in pediatric patients with severe aplastic anemia: a systematic review

Background

Acquired aplastic anemia (AAA) in pediatric patients is a rare disorder characterized by hypocellular bone marrow and pancytopenia. Eltrombopag, an oral thrombopoietin receptor agonist, provides a hematologic improvement in adults with severe aplastic anemia (SAA) refractory to immunosuppressive therapy (IST). The association of ELT and IST was approved by the US Food and Drug Administration (FDA) for adults and children ≥2 years of age as a first-line treatment for SAA. However, the effects of ELT on pediatric patients with SAA remain controversial and limited.

Methods and findings

We conducted a systematic review of the most recent literature from Pubmed, Web of Science, and Embase, published up to 20th December 2022, in order to evaluate the available evidence on the efficacy and safety of ELT added to IST for the treatment of SAA in the pediatric population.

Conclusion

Eltrombopag added to the IST has shown a good safety profile, without manifestations of excessive toxic effects, although not all the results obtained from our studies support the addition of ELT to the IST in the first-line treatment of children with SAA.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022325859.

Risk of Thromboembolism With Eltrombopag: A Case Report of Deep Vein Thrombosis and Bilateral Pulmonary Embolism

Eltrombopag is a second-line therapy for refractory thrombocytopenia from immune thrombocytopenic purpura (ITP). The medication is generally well tolerated but can lead to adverse thromboembolic complications in rare instances. We present a case of lower extremity deep vein thrombosis with bilateral pulmonary embolism in an ITP patient receiving eltrombopag. The patient underwent catheter-directed thrombolysis for pulmonary embolism. Eltrombopag was stopped on discharge, considering the potential cause of venous thrombosis.

A case of successful treatment with eltrombopag for severe immune-related thrombocytopenia induced by atezolizumab:Case report

Immune checkpoint inhibitors (ICIs) have shown impressive anti-tumor effects against multiple types of malignancies. Among the wide variety of immune-related adverse events (irAEs), immune-related thrombocytopenia (ITP) is relatively rare but often clinically significant and life-threatening. However, the appropriate treatment for severe ITP has not been determined. We herein report an 82-year-old male patient with non-small-cell lung cancer who developed severe ITP three weeks after starting the third course of atezolizumab. The initial combination therapy with high-dose prednisolone, intravenous immunoglobulin and platelet transfusion was ineffective. However, additional treatment with eltrombopag, a thrombopoietin receptor agonist, resulted in remarkable improvement in the thrombocytopenia. J. Med. Invest. 70 : 516-520, August, 2023.

Preeclampsia in a pregnant woman with severe aplastic anemia: A case report

A pregnant woman with severe aplastic anemia was managed using biweekly red blood cell transfusion and oral eltrombopag olamine administration during pregnancy. She was diagnosed with preeclampsia at 35 weeks of gestation. The severity of aplastic anemia is very important for predicting the course of pregnancy.

Evaluation of the procoagulant state in chronic immune thrombocytopenia before and after eltrombopag treatment-a prospective cohort study

BACKGROUND

Thrombopoietin receptor agonists are frequently used in treating immune thrombocytopenia (ITP) owing to high response rates and good tolerability. ITP is associated with an increased risk of thrombosis. Whether treatment with eltrombopag further increases this risk is controversial. The mechanisms behind the thrombotic risk in ITP are unclear.

OBJECTIVES

To assess platelet function and hypercoagulability in patients with ITP and the effect of eltrombopag thereon.

METHODS

This prospective multicenter study assessed adult primary patients with ITP who were starting eltrombopag treatment. Platelet (re)activity and hypercoagulability were measured in whole blood or plasma before start and after 2 to 3 weeks of eltrombopag treatment and compared with those of controls. Change over time was assessed by mixed-effects models, and the results were corrected for multiple testing.

RESULTS

We included 16 patients and 33 controls. At baseline, patients with ITP exhibited lower expression of glycoprotein VI, more activated platelets, and lower reactivity toward agonists compared with controls. β-Thromboglobulin levels reduced and thrombin generation peak height increased compared with those of controls. In line with this finding, patients with ITP showed high factor VIII (median, 217%; IQR, 174%-272%) and von Willebrand factor levels (median, 167%; IQR, 109%-198%). Eltrombopag treatment increased thrombin generation potential: lag time decreased and peak height and endogeneous thrombin potential increased. The latter changes were not significant after correction for multiple testing.

CONCLUSION

Patients with ITP in this study were in a hypercoagulable state, with preactivated platelets, increased thrombin generation potential, and increased levels of factor VIII and von Willebrand factor. Eltrombopag treatment further increased plasma thrombin generation potential but no other hemostatic parameters.

Successful Eltrombopag Therapy in a Child with MYH9-Related Inherited Thrombocytopenia

Inherited thrombocytopenias represents a heterogenous group of diseases characterized by a congenital reduction in the platelet count that could lead to a bleeding tendency. MYH9-related disorders are characterized by large platelets and congenital thrombocytopenia. Thrombopoietin-receptor agonists: eltrombopag and romiplostim are currently approved in many countries for the treatment of different forms of acquired thrombocytopenia, such as immune thrombocytopenia. We report, instead, the successful use of eltrombopag to treat inherited thrombocytopenia in a patient with an MHY9-related disease. This is the first report of a chronic use of eltrombopag to elevate platelets in MYH9-related disorders without side effects.

Switching between eltrombopag and recombinant human thrombopoietin in patients with immune thrombocytopenia: an observational study

BACKGROUND

Recombinant human thrombopoietin (rh-TPO) and eltrombopag are two distinct TPO receptor agonists (TPO-RAs) with different mechanisms. During the pandemic, when immunosuppressive medications are controversial, switching to another TPO-RA may be worth exploring in patients who do not benefit from their first TPO-RA. We investigated the outcomes of switching from rh-TPO to eltrombopag or vice versa in immune thrombocytopenia (ITP) patients.

METHODS

This prospective, open-label, observational investigation included 96 adult ITP patients who needed to switch between rh-TPO and eltrombopag between January 2020 and January 2021 at Peking University People's Hospital in China. The study evaluated response rates and platelet counts at different time points after the switch, bleeding events, time to response, duration of response, and adverse events.

RESULTS

At 6 weeks after switching, response was observed in 21/49 patients (43%) who switched for inefficacy and 34/47 patients (72%) who switched for non-efficacy-related issues. In the inefficacy group, 9/27 patients (33%) responded to eltrombopag, and 12/22 patients (55%) responded to rh-TPO. In the non-efficacy-related group, 21/26 (81%) and 13/21 (62%) patients in the eltrombopag and rh-TPO groups maintained their response rates at 6 weeks after switching, respectively. Response at 6 months was achieved in 24/49 patients (49%) switching for inefficacy and 37/47 patients (79%) switching for non-efficacy issues. In the inefficacy group, 13/27 patients (48%) responded to eltrombopag, and 11/22 patients (50%) responded to rh-TPO. In the non-efficacy-related group, 22/26 patients (85%) and 15/21 patients (71%) in the eltrombopag and rh-TPO groups maintained their response rates at 6 months after switching, respectively. Both eltrombopag and rh-TPO were well tolerated.

CONCLUSIONS

Our study confirmed the safety and effectiveness of switching between rh-TPO and eltrombopag for ITP patients who had no response to or experienced adverse events with their first TPO-RA. When the switch was motivated by other reasons, including patient preference and platelet count fluctuations, the probability of response was high.

REGISTRATION

ClinicalTrials.gov, NCT04214951.

Oral eltrombopag versus subcutaneous recombinant human thrombopoietin for promoting platelet engraftment after allogeneic stem cell transplantation: A prospective, non-inferiority, randomized controlled trial

Delayed platelet engraftment (DPE) is associated with poor survival and increased transplantation-related mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Therefore, treatments are needed to improve platelet engraftment and prevent DPE. We performed a phase three, non-inferior, randomized controlled study of eltrombopag or recombinant human thrombopoietin (rhTPO) to promot platelet engraftment after allo-HSCT. Candidates for allo-HSCT were randomly assigned to receive oral eltrombopag (50 mg daily) or subcutaneous rhTPO (15000U daily) from the first-day post-transplantation. The primary endpoint was the cumulative numbers of platelet engraftment (platelet recovery ≥20 × 10⁹ /L, without transfusion, for seven consecutive days) on day 60 after transplantation. We performed intention-to-treat analyses with a non-inferior margin of -15%. A total of 92 participants underwent randomization. 44 and 48 patients were randomized to the eltrombopag and rhTPO groups, respectively. The median duration of follow-up was 360 days (range: 12-960 days). The cumulative incidence of platelet engraftment on day 60 after transplantation in eltrombopag group was 86.4% (38/44) compared with 85.4% (41/48) in the rhTPO group (absolute risk difference [ARD] 1%, one-sided lower limit of 95% confidence interval [CI] -13.28%, P_{non-inferirioty}  = 0.014). The rate of DPE in the eltrombopag group was 6.8% (3/44) compared with 12.5% (6/48) in the rhTPO group (ARD -5.7%, one-sided higher limit of 95% CI 6.28%, P_{non-inferirioty}  = 0.063). Approximately, three-fourths of non-hematologic adverse events were not observed in the eltrombopag group but three patients (3/48, 6%) experienecd them in the rhTPO group. In addition, platelet transfusions unite from day 0 to day 21, or from day 22 to day 60, progression-free survival, overall survival were not significantly different between both groups. Eltrombopag was non-inferior to rhTPO in promoting platelet engraftment post allo-HSCT for patients with hematological malignancy. Oral eltrombopag was more convenient for patients than subcutaneous rhTPO (NCT03515096).

Phase Ib study of eltrombopag and azacitidine in patients with high-risk myelodysplastic syndromes and related disorders (the ELASTIC study)

Treating adverse risk myelodysplastic syndromes with azacitidine exacerbates thrombocytopenia. We report a study of eltrombopag in combination with azacitidine using a 3 + 3 cohort design. Patients with baseline platelets of <150 × 109 /l received eltrombopag ranging from 25 to 300 mg. An 8-day pre-phase of eltrombopag was followed by two cycles of combined therapy. Amongst 31 patients, there were no dose-limiting toxicities. The maximum tolerated dose (MTD) was 300 mg. Transient increases in bone marrow blasts at day 8 were common but no patient had protocol-defined progression following eltrombopag monotherapy. Marrow response rates after three and six treatment cycles were 32% and 29% respectively. In all, 70% of patients treated below and 36% treated at the MTD achieved a modified International Working Group 2006 platelet response at the end of cycle two. Of the platelet transfusion independent patients at baseline, 67% treated at the MTD became transfusion dependent during the first two cycles of treatment. Apart from lack of disease progression, our findings concur with a previously reported Phase III study (A StUdy of eltromboPag in myelodysPlastic SyndrOmes Receiving azaciTidine [SUPPORT]). We conclude that eltrombopag/azacitidine is safe in terms of conventional measures defined by adverse-event reporting. However, in light of SUPPORT and our own descriptive findings regarding efficacy, further combination studies in high-risk disease should be considered with caution.

Efficacy of Eltrombopag in Children with Post-Stem Cell Transplant Prolonged Isolated Thrombocytopenia

Prolonged isolated thrombocytopenia (PIT) is a complication following allogeneic hematopoietic cell transplantation that results in prolonged transfusion dependence. Recently, the efficacy of a thrombopoietin receptor agonist (eltrombopag) against PIT has been reported in adults; however, there are few reports in children. A 4-year-old male pediatric patient diagnosed with congenital pure red cell aplasia underwent allogeneic hematopoietic cell transplantation. Neutrophil engraftment was observed on post-transplant Day 26; however, platelet counts remained <10 × 109/L. Transfusions were required 1−2 times a week for at least 4 months. On post-transplant Day 124, oral eltrombopag (up to 2.4 mg/kg/day) was initiated. Thereafter, the platelet counts were maintained at ≥10 × 109/L, and the patient became transfusion independent. At 2 years and 6 months after the oral administration, no chromosomal abnormalities, thromboembolism, or myelofibrosis was observed. Thus, eltrombopag can be a potential treatment option for pediatric PIT.

Eltrombopag binds SDC4 directly and enhances MAPK signaling and macropinocytosis in cancer cells

Syndecan-4 (SDC4) is a single-pass transmembrane glycoprotein implicated in a variety of oncogenic signaling pathways. It is also an intrinsically disordered protein and considered "undruggable". In the present study, we confirmed that knocking out SDC4 in pancreatic cancer cells markedly impaired macropinocytosis, colony formation, as well as xenograft tumor initiation and growth. Quantitative proteomic profiling of Sdc4 knockout (KO) cells revealed significant changes in cell metabolic pathways. In a cellular protein-based ligand interaction screening, we identified that Eltrombopag (ETBP), an FDA-approved agonist of the thrombopoietin receptor (TPOR) for immune thrombocytopenia, could directly bind to SDC4 with a Kd value of ~2 µM. We showed that the transmembrane motif was essential for SDC4 binding to ETBP. Unexpectedly, ETBP not only increased SDC4 abundance, but also enhanced SDC4-associated MAPK signaling pathway and macropinocytosis in cancer cells. Our results indicate that ETBP is a potential agonist of SDC4 in a fashion similar to its original target TPOR, and that caution should be taken when using ETBP for chemotherapy-induced thrombocytopenia in cancer patients.