Eltrombopag: A Review in Paediatric Chronic Immune Thrombocytopenia

Exploratory study on the individualized application of eltrombopag in paediatric immune thrombocytopenia guided by therapeutic drug monitoring

There are variations in individual eltrombopag concentrations that may impact efficacy and adverse drug reactions (ADRs) in paediatric immune thrombocytopenia (ITP). To solve this problem, we tailored the eltrombopag dosage refer to concentration, then followed up to assess concentration value in paediatric ITP. This is a single-centre, prospective, observational study. The eltrombopag dosage was adjusted, and children were divided into three groups: the maintenance, discontinuation, and increase groups. Concentration and other data were compared to explore concentration value in guiding the individualized treatment of paediatric ITP. Thirty-nine patients were enrolled, including 23 in the maintenance group, 3 in the discontinued group and 13 in the increase group. 3 patients discontinued eltrombopag due to ADRs, which was significantly higher than patients in the maintenance group (t = 3.606, p = 0.001). In all, 13 patients increased their dosage due to poor response, whose concentration and platelet count were significantly lower than patients in the maintenance group (t = 2.461, p = 0.019; t = 4.633, p < 0.001). Two months after the increase, the number of patients reaching CR and R respectively increased by 2 and 3, while the median platelet count was significantly raised (Z = -2.411, p = 0.016). Concentration could be used as a reference index for the individualized treatment of eltrombopag in paediatric ITP.

Bioequivalence study of eltrombopag 75 mg film-coated tablets under fasting conditions during the Covid-19 pandemic in healthy Caucasian male subjects

This study aims to determine the bioequivalence of the reference preparation and the test preparation containing eltrombopag when both were given during the COVID-19 pandemic while fasting. Participants in the research were healthy male Caucasian subjects. One film-coated tablet of the test preparation or one film tablet of the reference preparation, equivalent to 75 mg of eltrombopag, was given to the participants in a randomized order throughout each treatment session. At pre determined blood sampling points, blood samples were taken to determine the pharmacokinetics of eltrombopag. Eltrombopag concentrations in the samples were determined using an LC-MS/MS technique verified using ESI(-). The study results were used to calculate the rate (the maximum plasma concentration, or Cmax) and extent (area under the concentration-time curve of plasma, or AUC(0-72) and AUC(0-t) of eltrombopag absorption from the test preparation and reference preparation. The 90% confidence intervals (CI) of the ln-transformed AUC(0-72), AUC(0-t), and Cmax of eltrombopag met the bioequivalence requirements of 80.00-125.00%. Both trial preparations had a similar and very satisfactory safety profile.

Clinical Care Team's Guide for Awareness on Risk Assessment of Eltrombopag Complicating Acute Kidney Injury in Relapsed Immune Thrombocytopenic Patients: A Case Report

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder caused by antigen-specific T cells and antiplatelet autoantibodies that inhibit platelet production in the bone marrow or destroy platelets in the spleen. ITP is a form of autoimmunity and is closely associated with inflammation. Corticosteroids are the first-line therapy for ITP, with a total response rate of 53-80%. However, corticosteroid therapy is associated with significant side effects and is often ineffective in patients with corticosteroid-resistant or -intolerant disease. Eltrombopag has been validated as a second-line option in ITP therapy. Despite several studies demonstrating the efficacy and safety of Eltrombopag in immune thrombocytopenia patients, the prevalence of Eltrombopag-induced acute kidney injury has been observed. This case report describes a patient who experienced acute kidney injury during Eltrombopag therapy. A sudden increase in serum creatinine to 6.7 mg/dL and metabolic acidosis occurred after eight weeks of Eltrombopag. The patient's renal failure had worsened, proteinuria was detected, and emergency hemodialysis was initiated. With vigilant kidney function screening and prompt treatment, the patient's renal function improved remarkably following cessation of Eltrombopag and initiation of hemodialysis. This case highlights the importance of comprehensive medication history-taking and vigilant kidney function screening in patients receiving Eltrombopag.

Indirect hyperbilirubinemia because of eltrombopag in two cases after autologous hematopoetic stem cell transplantation

ABSTRACT

The oral thrombopoietin receptor agonist eltrombopag has some side effects. One of them is related to bilirubin metabolism. Two patients with neuroblastoma in remission underwent stem cell transplantation with the Busulfan-melphalan regimen. Eltrombopag was started because of platelet engraftment failure. Indirect hyperbilirubinemia was detected after eltrombopag treatment. Laboratory and radiological investigations were all normal. The drugs and their side effects they used were examined. After eltombopag cutting, bilirubin levels of them returned to normal. These cases are presented to emphasize that eltrombopag can cause liver toxicity with hypertransaminesemia and hyperbilirubinemia. Drug side effects should be considered in the differential diagnosis of the patients. The significance of this case is that testing for serum aminotransferase and bilirubin levels should be monitored before and after eltrombopag use.

Palladium-Catalyzed Carbonylation of Aryl Bromides with Carbon Dioxide To Access Aryl Carboxylic Acids under Mild Conditions

A palladium-catalyzed direct carbonylation of aryl bromides with carbon dioxide as the carbonyl source has been developed by using Pd(dba)₂/DPEPhos as the catalyst under mild reaction conditions, providing an efficient route to a variety of aryl carboxylic acids in moderate to high yields. The methods have many advantages such as the use of a simple palladium catalyst system, wide substrate scope, good functional group tolerance, high yields, and easy scalability.

Eltrombopag-induced Metabolic Acidosis and Hepatic Encephalopathy in Pediatric ITP

Eltrombopag is approved for the treatment of chronic immune thrombocytopenia purpura (ITP) in pediatric patients 1 year and older who have demonstrated an insufficient response to corticosteroids and intravenous immunoglobulin. We present the case of a 2-year-old boy with chronic immune thrombocytopenia purpura who developed life-threatening adverse effects of acute liver failure, metabolic acidosis and encephalopathy with standard drug dosing. To our knowledge, this is the first case of eltrombopag-induced hepatic encephalopathy highlighting the critical need for prescribers to exercise caution when prescribing eltrombopag in the pediatric setting.

Pharmacokinetic Evaluation of Eltrombopag in ITP Pediatric Patients

Background: Eltrombopag (EPAG) is an oral thrombopoietin receptor agonist, approved for refractory primary immune thrombocytopenia (ITP) in pediatric patients. In two pediatric RCTs, EPAG led to an improvement of platelet counts and a reduction in bleeding severity. However, a significant number of pediatric patients did not achieve the primary endpoints. We performed a pharmacokinetic evaluation of EPAG in pediatric patients with refractory ITP. Methods: Outpatients aged from 1 to 17 y, affected by refractory ITP to first-line treatment, were enrolled for a pharmacokinetic assessment. The analysis of drug plasma concentration was performed by the LC-MS/MS platform. Non-compartmental and statistical subgroup analyses were carried out using the R package ncappc. Results: Among 36 patients eligible for PK analysis, the median dose of EPAG given once daily was 50 mg. The EPAG peak occurs between 2 and 4 h with a population Cmax and AUC 0-24 geo-mean of 23, 38 μg/ml, and 275, 4 µg*h/mL, respectively. The pharmacokinetic profile of EPAG did not show a dose proportionality. Female patients showed a statistically significant increase of dose-normalized exposure parameters, increasing by 110 and 123% for Cmax and AUC 0-24, respectively, when compared to male patients. Patients aged 1-5 y showed values increased by more than 100% considering both exposure parameters, compared to older children. Furthermore, patients presenting complete response (83%), showed augmented EPAG exposure parameters compared to subjects with partial or no response. Conclusion: These data highlight the need to further explore the variability of EPAG exposure and its pharmacokinetic/pharmacodynamic profile in pediatric patients also in a real-life setting.

Effects of Iron Chelation in Osteosarcoma

BACKGROUND

Osteosarcoma is an aggressive bone tumor. It represents the principal cause of cancer-associated death in children. Considering the recent findings on the role of iron in cancer, iron chelation has been investigated for its antineoplastic properties in many tumors. Deferasirox is the most used iron chelator compound and in previous studies showed an anticancer effect in hematologic and solid malignancies. Eltrombopag is a Thrombopoietin receptor used in thrombocytopenia that also binds and mobilize iron. It demonstrated an effect on iron overload conditions and also in contrasting cancer cell proliferation.

OBJECTIVE

We analyzed the effects of deferasirox and eltrombopag in human osteosarcoma cells in an attempt to identify other therapeutic approaches for this tumor.

METHODS

We cultured and treated with deferasirox and Eltrombopag, alone and in combination, two human osteosarcoma cell lines, MG63 and 143B. After 72h exposure, we performed RTqPCR, Western Blotting, Iron Assay and cytofluorimetric assays to evaluate the effect on viability, apoptosis, cell cycle progression and ROS production.

RESULTS

The iron-chelating properties of the two compounds are also confirmed in osteosarcoma, but we did not observe any direct effect on tumor progression.

DISCUSSION

We tested deferasirox and eltrombopag, alone and in combination, in human osteosarcoma cells for the first time and demonstrated that their iron-chelating activity does not influence biochemical pathways related to cancer progression and maintenance.

CONCLUSION

Although further investigations on possible effects mediated by cells of the tumor microenvironment could be of great interest, in vitro iron chelation in osteosarcoma does not impair tumor progression.

Effects of Eltrombopag on In Vitro Macrophage Polarization in Pediatric Immune Thrombocytopenia

Immune Thrombocytopenia (ITP) is an autoimmune disease characterized by autoantibodies-mediated platelet destruction, a prevalence of M1 pro-inflammatory macrophage phenotype and an elevated T helper 1 and T helper 2 lymphocytes (Th1/Th2) ratio, resulting in impairment of inflammatory profile and immune response. Macrophages are immune cells, present as pro-inflammatory classically activated macrophages (M1) or as anti-inflammatory alternatively activated macrophages (M2). They have a key role in ITP, acting both as effector cells, phagocytizing platelets, and, as antigen presenting cells, stimulating auto-antibodies against platelets production. Eltrombopag (ELT) is a thrombopoietin receptor agonist licensed for chronic ITP to stimulate platelet production. Moreover, it improves T and B regulatory cells functions, suppresses T-cells activity, and inhibits monocytes activation. We analyzed the effect of ELT on macrophage phenotype polarization, proposing a new possible mechanism of action. We suggest it as a mediator of macrophage phenotype switch from the M1 pro-inflammatory type to the M2 anti-inflammatory one in paediatric patients with ITP, in order to reduce inflammatory state and restore the immune system function. Our results provide new insights into the therapy and the management of ITP, suggesting ELT also as immune-modulating drug.

Safety and Efficacy of Eltrombopag in Children and Adults with Immune Thrombocytopenia: A Systematic Review and Meta-Analysis

Immune thrombocytopenia is an immune condition where antibodies are produced against platelets. Eltrombopag is a thrombopoietin receptor agonist that stimulates and promotes platelet production approved for treating thrombocytopenia in patients with chronic immune thrombocytopenia, where other treatments such as corticosteroids, splenectomy or immunoglobulins are inadequate. The aim of this meta-analysis was to evaluate the efficacy and safety of the eltrombopag in adults and children with immune thrombocytopenia. We included 7 studies with a total of 765 patients (606 adults and 159 children). We evaluated the number of patients that achieved a post-treatment platelet count equal or above 50x10⁹/L (primary result-target) without the need of rescue treatment for at least 4 weeks. Our data showed that patients who received eltrombopag were almost 4 times more probable in achieving the primary target when compared to patients who received placebo (RR 3.84, 95% CI 2.39 to 6.14; I² = 46%). The number of patients needed rescue treatment and the number of bleeding incidents were reduced in the group that received eltrombopag when compared to those who received placebo (RR 0.40, 95% CI 0.25 to 0.62; I² = 40%) (RR 0.74, 95% CI 0.62 to 0.89; I² = 68%). The total number of side effects did not statistically differ between the two groups (RR 0.99, 95% CI 0.90 to 1.08; I² = 14%). Our findings were similar to previously published studies and confirm that eltrombopag is safe and efficient in immune thrombocytopenia. However, more clinical trials are needed in order to enhance our findings.

Outcomes of Eltrombopag Treatment and Development of Iron Deficiency in Children with Immune Thrombocytopenia in Turkey

Objective

Immune thrombocytopenia (ITP) is a rare autoimmune disease and hematologic disorder characterized by reduced platelet counts that can result in significant symptoms, such as bleeding, bruising, epistaxis, or petechiae. The thrombopoietin receptor agonist eltrombopag (EPAG) is a second-line agent used to treat chronic ITP purpura in adults and children.

Materials and Methods

The present retrospective study evaluated the efficacy, safety, and side effects of EPAG treatment in pediatric patients with acute refractory and chronic immune thrombocytopenia, particularly focusing on iron-deficiency anemia.

Results

The diagnosis was chronic ITP in 89 patients and acute refractory ITP in 16 patients. The mean age of patients was 9.5±4.5 years (minimum-maximum: 1.2-18 years) at the beginning of EPAG treatment. The overall response rate was 74.3% (n=78). The mean time for platelet count of ≥50x109/L was 11.6±8 weeks (range: 1-34 weeks). The treatment was stopped for 27 patients (25.7%) at an average of 6.8±9 months (range: 1-38 months). The reason for discontinuation was lack of response in 18 patients, nonadherence in 4 patients, and hepatotoxicity in 2 patients. Response to treatment continued for an average of 4 months after cessation of EPAG in 3 patients.

Conclusion

Results of the current study imply that EPAG is an effective therapeutic option in pediatric patients with acute refractory and chronic ITP. However, patients must be closely monitored for response and side effects during treatment, and especially for iron deficiency.

[Eltrombopag for the treatment of primary immune thrombocytopenia in 23 pediatric patients]

Objective: To evaluate the efficacy and safety of eltrombopag in the treatment of pediatric primary immune thrombocytopenia (ITP) . Methods: The clinical characteristics of 23 pediatric ITP patients who received eltrombopag from May 2015 to March 2019 were retrospectively analyzed. Eltrombopag started with an initial dose of 12.5-50.0 mg/d and the maximum dose was 75.0 mg/d. Results: Among 23 children, there were 11 boys and 12 girls with median age 11.0 (2.0-17.0) years. Four cases were newly diagnosed ITP, the other 8 of persistent ITP and 11 of chronic ITP. The duration of eltrombopag application ranged from 4.5 to 95 weeks (8/23 still ongoing) . The median platelet (PLT) counts at 2 weeks, 4 weeks, 3 months and the 6 months after treatment were 40 (4-170) ×10(9)/L, 20 (4-130) ×10(9)/L, 60 (4-110) ×10(9)/L, and 70 (18-160) ×10(9)/L, which were all significantly higher than that before treatment 14 (2-82) ×10(9)/L (z=-3.440, P=0.001; z=-1.964, P=0.049; z=-4.339, P<0.001;z=-5.794, P<0.001 respectively) . The overall response rate was 60.87% (14/23 cases) . The median time to PLT count ≥30×10(9)/L was 10.5 (3-42) days. Seven patients (30.43%) responded within the first week, and 10 cases (43.48%) achieved PLT counts ≥30×10(9)/L within 2 weeks. All patients were divided into three groups according to the age (<6 years old, 6-12 years old, 13-17 years old) . The response rates were similar in three groups, as 33.33%, 60.00%, 85.71%, respectively. WHO bleeding scores as 0, 1, 2 were corresponded to 4, 12 and 7 patients before treatment. Patient numbers changed to 13, 7, 3 with bleeding scores 0, 1, 2 respectively after treatment (χ(2)=7.558, P=0.006) . Eltrombopag was well tolerated, the common adverse events included elevated transaminase (4 cases) and serum bilirubin (4 cases) ; mild nausea (1 case) , vomiting (1 case) and dizziness (1 case) . No drug withdrawal occurred due to adverse events. Conclusion: Eltrombopag is safe and effective in pediatric patients with primary ITP.

Eltrombopag for use in children with immune thrombocytopenia

Eltrombopag is currently the only US Food and Drug Administration-approved thrombopoietin receptor agonist for the treatment of chronic immune thrombocytopenia (ITP) in children. This oral, once-per-day therapy has shown favorable efficacy and adverse effect profiles in children. Two multicenter, double-blind, placebo controlled clinical trials (PETIT [Efficacy and Safety Study of Eltrombopag in Pediatric Patients With Thrombocytopenia From Chronic Idiopathic Thrombocytopenic Purpura (ITP)] and PETIT2 [Study of a New Medication for Childhood Chronic Immune Thrombocytopenia (ITP), a Blood Disorder of Low Platelet Counts That Can Lead to Bruising Easily, Bleeding Gums, and/or Bleeding Inside the Body]) demonstrated efficacy in raising platelet counts, reducing bleeding, and reducing the need for concomitant ITP therapies with relatively few adverse effects. The most commonly reported drug-related adverse effects include headache, nausea, and hepatobiliary laboratory abnormalities. Long-term safety data in children are limited, and studies in adults have not revealed a clinically significant increased incidence of thrombosis, marrow fibrosis, or cataract formation. Eltrombopag has also been approved for treating refractory severe aplastic anemia (AA) and has potential for expanded use in ITP and severe AA as well as in other conditions associated with thrombocytopenia.

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

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

Eltrombopag-Induced Acute Liver Failure in a Pediatric Patient: A Pharmacokinetic and Pharmacogenetic Analysis

Eltrombopag is an oral thrombopoietin receptor agonist approved for the treatment of patients with chronic idiopathic thrombocytopenic purpura (ITP), who are more than 1 year old, and show poor response to first-line therapy. ITP is a hematological disorder characterized by isolated thrombocytopenia in the absence of secondary causes or disorders. Eltrombopag is generally well tolerated in the pediatric population; therefore, therapeutic drug monitoring (TDM) is not usually performed in clinical practice.We presented the case study of a 3-year-old girl with chronic ITP. She arrived in the pediatric intensive care unit with acute liver failure due to eltrombopag toxicity despite taking the standard drug dosage. A very high eltrombopag plasma concentration, indicating drug toxicity, was found through TDM. The patient also carried the allelic variations that are involved in drug metabolism [CYP2C8 and UDP glucuronosyltransferase (UGT) 1A1 (UGT1A1)] and drug cellular transportation [ABCG2 (ATP-binding cassette G2)]. This observation highlights the importance of using TDM and pharmacogenetic approaches to manage patients' unusual complications associated with standard pharmacological treatment regimens.

Iron chelating properties of Eltrombopag: Investigating its role in thalassemia-induced osteoporosis

Chronic blood transfusions are responsible to cause iron overload, which leads to several complications to end organs and osteoporosis. Iron chelation is needed to remove iron excess and to contain bone-mass loss. Deferasirox is the most recent oral iron chelator that prevents transfusion related iron overload complications. Recently Eltrombopag (ELT) iron chelating properties are emerging. ELT is an agonist at Thrombopoietin receptor, used in treatment of thrombocytopenia. We tested ELT and Deferasirox in iron overloaded osteoclasts from thalassemic patients and donors measuring intracellular iron, TRAP expression and osteoclast activity. We confirmed ELT iron chelation capacity also in bone tissue and a synergic effect when used with Deferasirox. Moreover, having demonstrated its effects on osteoclast activity, we suggest for the first time that ELT could ameliorate bone tissue’s health reducing bone mass loss.

Eltrombopag For Immune Thrombocytopenic Children in a Single Region

Objective Child patients of chronic thrombocytopenic purpura with severe and resistant thrombocytopenia were evaluated to observe whether their clinical or laboratory states improve by one of the thrombomimetic therapeutic agent called Eltrombopag as in adults in a single center of different country from previous studies. Materials and Methods Nineteen patients with chronic immune thrombocytopenia were treated with Eltrombopag to dose in international guidelines. Results Approximately half (11/19:58%) of the patients benefitted from the treatment with Eltrombopag either by an increase of platelet levels at safe levels with a decrease in the frequency of bleedings which needed rescue treatment. Conclusion Thrombomimetic treatment options have strengthened the clinician's hand where the regular treatment options became insufficient.

Efficacy and safety of thrombopoietin receptor agonists in children with chronic immune thrombocytopenia: a meta-analysis

BACKGROUND AND AIM

Thrombopoietin receptor agonists (TPO-RAs) have been shown to be safe and effective for adults with chronic immune thrombocytopenia (ITP). The aim of this meta-analysis is to assess the efficacy and safety of thrombopoietin receptor agonists for children with chronic ITP.

MATERIALS AND METHODS

Clinical randomized controlled trials (RCTs) evaluating the efficacy and safety of TPO-RAs in pediatric ITP patients published up to June 2017 were retrieved from PubMed, Cochrane Library, and Embase databases. Relevant data were extracted, and the Physiotherapy Evidence Database scale was used to assess the methodological quality. Stata/SE 12.0 was used to perform a meta-analysis.

RESULTS

Seven RCTs were included, with 238 patients and 107 patients in the TPO-RA group and the control group, respectively. Assessing efficacy, better results were found in the TPO-RA group for the rate of overall platelet response, durable response, and rescue medication needed. Furthermore, the TPO-RA group yielded superior results in the incidence of clinically significant bleeding events but had a comparable result in the incidence of any bleeding events and severe bleeding events. No significant difference was found between the two groups in health-related quality of life and parental burden. Assessing safety, no significant difference was found between the two groups in the incidence of any adverse events and severe adverse events.

CONCLUSIONS

TPO-RAs are effective and safe agents for the treatment of chronic ITP in pediatric patients. Eltrombopag appears to be better than romiplostim in terms of the rate of rescue medication needed and clinically significant bleeding events.

Prognostic Factors for Immune Thrombocytopenia Outcome in Greek Children: A Retrospective Single-Centered Analysis

Immune thrombocytopenia (ITP) in children has a varied course and according to duration is distinguished as newly diagnosed (<3 months), persistent (3-12), and chronic (>12) types. Several studies have evaluated the prognostic factors for the progression of the disease, but similar works have yet to be performed in Greece. We aimed to identify prognostic markers for the three forms of the disease in 57 Greek children during a 13-year period. Information regarding age, gender, preceding infection, bleeding type, duration of symptoms and platelets at diagnosis, treatment, disease course, and immunological markers was recorded. 39 children had newly diagnosed, 4 persistent, and 14 chronic disease. Chronic ITP children were more likely to be of age > 10 years (p = 0.015) and have gradual initiation of the disease (p = 0.001), platelets > 10 × 10⁹/L (p = 0.01), and impaired immunological markers (p < 0.003) compared to newly diagnosed/persistent groups. Recent history of infection was found mainly in the newly diagnosed/persistent group (p = 0.013). None of the children exhibited severe spontaneous bleeding. Conclusion. Even though ITP in children usually has a self-limited course, with rare serious bleeding complications, the chronic form of the disease is characterized by different predictive parameters, which can be used in clinical practice.