Update on diagnosis and treatment of immune thrombocytopenia

Construction of a clinical prediction model for the diagnosis of immune thrombocytopenia based on clinical laboratory parameters

PURPOSE

Primary immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia that is often misdiagnosed due to the lack of a gold standard for diagnosis and currently relies on exclusionary approaches. This project combines several laboratory parameters to construct a clinical prediction model for adult ITP patients.

METHODS

A total of 428 patients with thrombocytopenia who visited the West China Hospital of Sichuan University between January 2021 and March 2023 were enrolled. Based on the diagnostic criteria, we divided those patients into an ITP group and a non-ITP group. A total of 34 laboratory parameters were analyzed via univariate analysis and correlation analysis, and the least absolute shrinkage and selection operator regression analysis was used to establish the model. The training and validation sets were divided at a ratio of 7:3, and we used a fivefold cross-validation method to construct the model.

RESULTS

The model included the following variables: red blood cell, mean corpuscular hemoglobin concentration, red blood cell distribution width-standard deviation, platelet variability index score, immature platelet fraction, lymphocyte absolute value. The prediction model exhibited good performance, with a sensitivity of 0.89 and a specificity of 0.83 in the training set and a sensitivity of 0.90 and a specificity of 0.87 in the validation set.

CONCLUSION

The clinical prediction model can assess the probability of ITP in thrombocytopenic patients and has good predictive accuracy for the diagnosis of ITP.

Study on diagnostic-sensitive markers of primary immune thrombocytopaenia in children based on plasma proteomics

To use proteomic techniques to identify sensitive diagnostic biomarkers for paediatric immune thrombocytopenia (ITP). We selected children in ITP and control groups, using a four-dimensional data-independent acquisition approach (4D-DIA) to analyse its protein expression. The significantly differentially expressed proteins were selected for enzyme-linked immunosorbent assay (ELISA) validation in a cohort comprising 50 samples (13 healthy controls, 15 secondary thrombocytopenia controls and 22 children with ITP). Receiver operating characteristics (ROC) were generated to diagnose ITP and to assess the diagnostic effectiveness of this approach. Compared with the control group, 55 differentially expressed proteins (43 increased and 12 decreased) were determined in the ITP group. Matrix metalloproteinases-9 (MMP-9) and thrombospondin-1 (THBS1) were significantly expressed and selected for ELISA. The verification outcomes aligned with the findings from the proteomic examinations. In contrast to the control cohort, the ITP subjects exhibited markedly elevated plasma MMP-9 levels and reduced plasma THBS1 concentrations. Additionally, the ROC curves indicated the diagnostic value of these biomarkers. In conclusion, proteomics facilitates identifying the sensitive biomarkers for ITP diagnosis. We have preliminarily selected two differentially expressed proteins, MMP-9 and THBS1, whose potential role as biomarkers for diagnosing ITP requires further research.

Comprehensive analysis and prediction model of mitophagy and ferroptosis in primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is linked to specific pathogenic mechanisms, yet its relationship with mitophagy and ferroptosis is poorly understood. This study aimed to identify new biomarkers and explore the role of mitophagy and ferroptosis in ITP pathogenesis. Techniques such as differential analysis, Mfuzz expression pattern clustering, machine learning, gene set enrichment analysis, single-cell RNA sequencing (scRNA-seq) and immune infiltration analysis were employed to investigate the molecular pathways of pivotal genes. Two-sample Mendelian randomization (TSMR) assessed the causal effects in ITP. Key genes identified in the training set included GABARAPL1, S100A8, LIN28A, and GDF9, which demonstrated diagnostic potential in validation sets. Functional analysis indicated these genes' involvement in ubiquitin phosphorylation, PPAR signalling pathway and T-cell differentiation. Immune infiltration analysis revealed increased macrophage presence in ITP, related to the critical genes. scRNA-seq indicated reduced GABARAPL1 expression in ITP bone marrow macrophages. TSMR linked S100A8 with ITP diagnosis, presenting an OR of 0.856 (95% CI = 0.736-0.997, p = 0.045). The study pinpointed four central genes, GABARAPL1, S100A8, LIN28A, and GDF9, tied to mitophagy and ferroptosis in ITP. It posits that diminished GABARAPL1 expression may disrupts ubiquitin phosphorylation and PPAR signalling, impairing mitophagy and inhibiting ferroptosis, leading to immune imbalance.

HLA-DRB5 promotes immune thrombocytopenia via activating CD8+ T cells

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by a low platelet (PLT) count and a high risk of bleeding, the clinical treatment for which still needs to be upgraded. Based on the critical role of human leukocyte antigen class II heterodimer β5 (HLA-DRB5) in immune system, we herein investigated its effect on ITP. ITP murine models were established by the injection of guinea pig anti-mouse platelet serum (GP-APS), and the PLT of mouse peripheral blood was counted during the modeling. Quantitative real-time reverse transcription polymerase chain reaction, western blot and immunofluorescence assay was performed to quantify expressions of HLA-DRB5, major histocompatibility complex II (MHC-II) and co-stimulatory molecules (CD80, CD86). Flow cytometry was conducted to analyze the percentage of CD8+ T cells. As a result, the PLT count was decreased in mouse peripheral blood. Expressions of HLA-DRB5, MHC-II and co-stimulatory molecules, as well as the percentage of CD8+ T cells were elevated in peripheral blood of ITP mice. HLA-DRB5 knockdown mitigated ITP by increasing peripheral PLT level, downregulating expressions of MHC-II and co-stimulatory molecules and inactivating CD8+ T cells. Collectively, the downregulation of HLA-DRB5 restores the peripheral PLT count in ITP mice by reducing MHC-II-mediated antigen presentation of macrophages to inhibit the activation of CD8+ T cells.

Antagonism of the Platelet-Activating Factor Pathway Mitigates Inflammatory Adverse Events Driven by Anti-erythrocyte Antibody Therapy in Mice

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts primarily due to antiplatelet autoantibodies. Anti-D is a donor-derived polyclonal Ab against the rhesus D Ag on erythrocytes used to treat ITP. Unfortunately, adverse inflammatory/hypersensitivity reactions and a Food and Drug Administration-issued black box warning have limited its clinical use. This underscores the imperative to understand the inflammatory pathway associated with anti-erythrocyte Ab-based therapies. TER119 is an erythrocyte-specific Ab with anti-D-like therapeutic activity in murine ITP, while also exhibiting a distinct inflammatory signature involving production of CCL2, CCL5, and CXCL9 but not IFN-γ. Therefore, TER119 has been used to elucidate the potential mechanism underlying the adverse inflammatory activity associated with anti-erythrocyte Ab therapy in murine ITP. Prior work has demonstrated that TER119 administration is associated with a dramatic decrease in body temperature and inflammatory cytokine/chemokine production. The work presented in the current study demonstrates that inhibiting the highly inflammatory platelet-activating factor (PAF) pathway with PAF receptor antagonists prevents TER119-driven changes in body temperature and inhibits the production of the CCL2, CCL5, and CXCL9 inflammatory cytokines in CD-1 mice. Phagocytic cells and a functional TER119 Fc region were found to be necessary for TER119-induced body temperature changes and increases in CXCL9 and CCL2. Taken together, this work reveals the novel requirement of the PAF pathway in causing adverse inflammatory activity associated with anti-erythrocyte Ab therapy in a murine model and provides a strategy of mitigating these potential reactions without altering therapeutic activity.

Cepharanthine synergistically promotes methylprednisolone pharmacodynamics against human peripheral blood mononuclear cells possibly via regulation of P-glycoprotein/glucocorticoid receptor translocation

BACKGROUND

Cepharanthin® alone or in combination with glucocorticoid (GC) has been used to treat chronic immune thrombocytopenia (ITP) since the 1990s. Cepharanthine (CEP) is one of the main active components of Cepharanthin®. The purpose of this study was to investigate the effects of CEP on GC pharmacodynamics on immune cells and analyse the possible action mechanism of their interactions.

METHODS

Peripheral blood mononuclear cells (PBMCs), T lymphocytic leukemia MOLT-4 cells and daunorubicin resistant MOLT-4 cells (MOLT-4/DNR) were used to evaluate the pharmacodynamics and molecular mechanisms. Drug pharmacodynamics was evaluated by WST-8 assay. P-glycoprotein function was examined by rhodamine 123 assay. CD4+CD25+Foxp3+ regulatory T cells and Th1/Th2/Th17 cytokines were detected by flow cytometry. P-glycoprotein expression and GC receptor translocation were examined by Western blot.

RESULTS

CEP synergistically increased methylprednisolone (MP) efficacy with the suppressive effect on the cell viability of PBMCs. 0.3 and 1 μM of CEP significantly inhibited P-glycoprotein efflux function of CD4+ cells, CD8+ cells, and lymphocytes (P<0.05). 0.03~3 μM of CEP also inhibited the P-glycoprotein efflux function in MOLT-4/DNR cells in a concentration-dependent manner (P<0.001). However, 0.03~3 μM of CEP did not influence P-glycoprotein expression. 0.03~0.3 μM of CEP significantly increased the GC receptor distribution from the cytoplasm to the nucleus in a concentration-dependent manner in MOLT-4/DNR cells. The combination did not influence the frequency of CD4+, CD4+CD25+ and CD4+CD25+Foxp3+ T cells or the secretion of Th1/Th2/Th17 cytokines from PBMCs. In contrast, CEP alone at 1 μM decreased the percentage of CD4+ T cell significantly (P<0.01). It also inhibited the secretion of IL-6, IL-10, IL-17, TNF-α, and IFN-γ.

CONCLUSIONS

CEP synergistically promoted MP pharmacodynamics to decrease the cell viability of the mitogen-activated PBMCs, possibly via inhibiting P-glycoprotein function and potentiating GC receptor translocation. The present study provides new evidence of the therapeutic effect of Cepharanthin® alone or in combination with GC for the management of chronic ITP.

Comprehensive analysis of the clinical manifestations and hematological parameters associated with secondary immune thrombocytopenia in patients with primary Sjögren syndrome: An observational study

Primary Sjögren Syndrome (pSS) is a chronic autoimmune disease that primarily affects exocrine glands and can lead to various extraglandular manifestations, including secondary immune thrombocytopenia (ITP). Understanding the clinical and hematological differences in pSS patients with and without secondary ITP is crucial for improved patient management and treatment strategies. This retrospective study, conducted from January 2020 to December 2023, involved a cohort of pSS patients, dividing them into 2 groups: those with secondary ITP and those without. Patients were evaluated using the European League Against Rheumatism Sjögren Syndrome Disease Activity Index (ESSDAI), EULAR Sjögren Syndrome Patient-Reported Index (ESSPRI), Health Assessment Questionnaire, and other hematological parameters. Inclusion criteria were based on the American-European Consensus Group or ACR/EULAR classification criteria for pSS. Exclusion criteria included other autoimmune or hematological disorders, prior splenectomy, recent blood transfusions, and lack of informed consent. Statistical analysis was performed using SPSS software, with various tests applied to analyze the data, including logistic regression to identify risk factors for secondary ITP. Significant differences were noted in fatigue, lymphadenopathy, arthritis, mean age, and ESSDAI scores between the secondary ITP and non-secondary ITP groups. Patients with secondary ITP exhibited higher platelet counts, more prevalent lymphopenia, higher immunoglobulin G (IgG) levels, lower complement 3 levels, and reduced white blood cell and hemoglobin levels. Logistic regression analysis identified lymphadenopathy as a risk factor and arthritis as a protective factor for the development of secondary ITP. The study reveals distinct clinical and hematological characteristics in pSS patients with secondary ITP, suggesting a higher disease activity in this subset. These findings underscore the need for further exploration of these associations to develop more precise treatment approaches for pSS, focusing on preventing secondary ITP and improving patient outcomes.

Thrombopoietin receptor agonists use and risk of thrombotic events in patients with immune thrombocytopenic purpura: A systematic review and meta‑analysis of randomized controlled trials

Thrombopoietin receptor agonists (TPO-RAs) have a role in second-line immune thrombocytopenic purpura (ITP) treatment, binding to and activating thrombopoietin receptors on megakaryocyte membranes in the bone marrow. This promotes megakaryocyte maturation and increases platelet production. Despite a 2-6% incidence of thrombotic events during TPO-RA treatment, it remains uncertain whether TPO-RAs elevate thrombosis rates. A comprehensive search of electronic databases was conducted using the relevant search criteria. To assess the risk of bias, the included studies were assessed using the revised Cochrane Risk of Bias Assessment Tool 2.0, and a meta-analysis was performed using RevMan 5.4.1. A total of 1,698 patients with ITP were included from randomized controlled trials (RCTs). There were 26 thromboembolic events in the TPO-RAs group and 4 in the control group. However, there was no significant difference in the incidence of thrombotic events between the two groups [odds ratio (OR)=1.76, 95% confidence interval (CI): 0.78-4.00, P=0.18], even if the duration of treatment was >12 weeks (OR=2.46, 95% CI: 0.81-7.43, P=0.11). Subgroup analysis showed that none of the four drugs significantly increased the incidence of thrombotic events (romiplostim: OR=0.92, 95% CI: 0.14-6.13, P=0.93; eltrombopag: OR=2.32, 95% CI: 0.64-8.47, P=0.20; avatrombopag: OR=4.15, 95% CI: 0.20-85.23, P=0.36; and hetrombopag: OR=0.76, 95% CI: 0.03-18.76, P=0.87). There was also no significant difference in the results of the double-blinded placebo-controlled RCTs (OR=1.21, 95% CI: 0.41-3.58, P=0.73). Compared to patients with ITP who did not receive TPO-RA treatment, those receiving TPO-RA treatment did not exhibit a significantly increased risk of thrombotic events.

Prediction of Treatment Effect of SLE-ITP Patients Based on Cost-Sensitive Neural Network and Variational Autoencoder

OBJECTIVE

The aim of the study was to examine the factors influencing the therapeutic effect of patients with systemic lupus erythematosus combined with immune thrombocytopenia (SLE-ITP) and develop a prediction model to predict the therapeutic effect of SLE-ITP.

METHODS

Three hundred twenty-four SLE-ITP patients were retrieved from the electronic health record database of SLE patients in Jiangsu Province according to the latest treatment response criteria for ITP. We adopted the Cox model based on the least absolute shrinkage and selection operator to explore the impact factors affecting patient therapeutic effect, and we developed neural network model to predict therapeutic effect, and in prediction model, cost-sensitivity was introduced to address data category imbalance, and variational autoencoder was used to achieve data augmentation. The performance of each model was evaluated by accuracy and the area under the receiver operator curve.

RESULTS

The results showed that B-lymphocyte count, H-cholesterol level, complement-3 level, anticardiolipin antibody, and so on could be used as predictors of SLE-ITP curative effect, and abnormal levels of alanine transaminase, immunoglobulin A, and apolipoprotein B predicted adverse treatment response. The neural network treatment effect prediction model based on cost-sensitivity and variational autoencoder was better than the traditional classifiers, with an overall accuracy rate closed to 0.9 and a specificity of more than 0.9, which was useful for clinical practice to identify patients at risk of ineffective treatment response and to achieve better individualized management.

CONCLUSIONS

By predicting the curative effect of SLE-ITP, the severity of patients can be determined, and then the best treatment strategy can be planned to avoid ineffective treatment.

Tacrolimus shows adequate efficacy in patients with antiphospholipid antibodies associated thrombocytopenia: a retrospective cohort study

Thrombocytopenia is a common manifestation associated with the presence of antiphospholipid antibodies (aPL). The aim of this study is to investigate the efficacy and safety of tacrolimus treatment in aPL associated thrombocytopenia. This is a single-center retrospective study. Patients who had persistent positive aPL and thrombocytopenia that was treated with tacrolimus were included. A total of 49 patients [38 females (77.6%)] were enrolled from Nov 2013 to Apr 2022 with a median treatment duration of 22 months. Seventeen fulfilled classification criteria of antiphospholipid syndrome (APS), 18 systemic lupus erythematosus (SLE). The median age of study patients was 37 years (IQR 31, 48). Forty-three (87.8%) patients were on concomitant use of glucocorticoids, 6 on tacrolimus monotherapy. The overall response rate in this cohort was 85.7% (n = 42), including 49% of complete responses (n = 24). The median time to achieve a response was 3 months. Nine (18.4%) patients with overall response experienced a loss of response. The response rate during follow-up in patients with monotherapy was noninferior. Patients with positive antinuclear antibody (ANA) showed the tendency of maintaining response (p = 0.028). The 19 patients who were on medium and high dosage of glucocorticoids (> 15 mg prednisone/d) managed to taper glucocorticoids rapidly. Side effects were reported in 12.2% (n = 6) of the patients (elevated creatinine, general malaise, elevated liver enzyme). Tacrolimus has adequate efficacy, steroid-sparing effect and is well tolerated for aPL associated thrombocytopenia. Patients with positive ANA might benefit the most from tacrolimus treatment.

Bleeding risk assessment in immune thrombocytopenia

The bleeding risk in immune thrombocytopenia (ITP) is related not only to low platelet count but also to the presence of platelet dysfunction. However, diagnosing a concomitant platelet dysfunction is challenging as most of the available platelet function assays (PFAs) require a platelet count of greater than 100,000/μL. Sonoclot coagulation and platelet function analyzer works on the principle of viscoelastometry, and results remain unaffected by the platelet counts. To assess the platelet function in adult acute ITP patients with the help of sonoclot coagulation and platelet function analyzer and correlate it with the risk of bleeding. Newly diagnosed acute ITP patients with a platelet count less than 20,000/μL were divided into two groups based on WHO bleeding grade: ITP non-bleeder (ITP-NB) group (WHO bleeding grade ≤1) and ITP bleeder (ITP-B) group (WHO bleeding grade ≥2). Platelet function was assessed by sonoclot in both groups. The patients without significant bleeding (ITP-NB) were followed up monthly for six months with the assessment of platelet function during each contact. Eighty patients (30 ITP-B and 50 ITP-NB) were prospectively included in this study. The median age of patients in the two groups was 37 years and 30 years, respectively. The female-to-male ratio was 4:1 and 1:1 in ITP-B and ITP-NB groups. The median platelet count in ITP-B and ITP-NB was 12000/μL (range 1000-19000/μL) and 8000/μL (range 1000-19000/μL), respectively. Mean platelet functions by sonoclot in both groups were lower than the normal cut-off (>1.6). However, the mean platelet function in the ITP-B group (0.2 + 0.17) was significantly lower than the ITP-NB group (1.2 ± 0.52) (p = 0.01). During the follow-up period of 6 months, patients in ITP-NB with a normal platelet function (>1.6) on sonoclot had lesser episodes (one episode) of clinically significant bleeding than patients with a low platelet function (4 episodes). Patients with acute severe thrombocytopenia and bleeding phenotype have a greater abnormality on platelet function by sonoclot than patients with non-bleeding phenotype. This information may help in taking therapeutic decisions in patients with acute ITP.

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.

Xanthotoxin, a novel inducer of platelet formation, promotes thrombocytopoiesis via IL-1R1 and MEK/ERK signaling

BACKGROUND

Thrombocytopenia is a common hematological disease caused by many factors. It usually complicates critical diseases and increases morbidity and mortality. The treatment of thrombocytopenia remains a great challenge in clinical practice, however, its treatment options are limited. In this study, the active monomer xanthotoxin (XAT) was screened out to explore its medicinal value and provide novel therapeutic strategies for the clinical treatment of thrombocytopenia.

METHODS

The effects of XAT on megakaryocyte differentiation and maturation were detected by flow cytometry, Giemsa and phalloidin staining. RNA-seq identified differentially expressed genes and enriched pathways. The signaling pathway and transcription factors were verified through WB and immunofluorescence staining. Tg (cd41: eGFP) transgenic zebrafish and mice with thrombocytopenia were used to evaluate the biological activity of XAT on platelet formation and the related hematopoietic organ index in vivo.

RESULTS

XAT promoted the differentiation and maturation of Meg-01 cells in vitro. Meanwhile, XAT could stimulate platelet formation in transgenic zebrafish and recover platelet production and function in irradiation-induced thrombocytopenia mice. Further RNA-seq prediction and WB verification revealed that XAT activates the IL-1R1 target and MEK/ERK signaling pathway, and upregulates the expression of transcription factors related to the hematopoietic lineage to promote megakaryocyte differentiation and platelet formation.

CONCLUSION

XAT accelerates megakaryocyte differentiation and maturation to promote platelet production and recovery through triggering IL-1R1 and activating the MEK/ERK signaling pathway, providing a new pharmacotherapy strategy for thrombocytopenia.

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.

Real-world experience of anti-D immunoglobulin in immune thrombocytopenia

In developing countries, anti-D has been used in immune thrombocytopenia (ITP) as a cheaper alternative to human immunoglobulin. We aim to analyze the response and safety profile of anti-D in patients with severe ITP. A retrospective study was conducted at a tertiary care hospital in Northern India. Patients received a single intravenous infusion of 75 μg/kg anti-D. In total, 36 patients (20 females) were included in this study. The median duration from ITP diagnosis to anti-D therapy was 235 days (range 1-1613 days). Four (11.1%) patients received anti-D as an upfront treatment. The patients' platelet counts rose significantly by the end of day three and continued to be significantly high until day 30 of receiving anti-D (p ≤ 0.001). The overall response rate (ORR) by day seven was 88.89%. There was no effect of age, sex, duration of disease, prior therapy, and platelet count on the ORR. Patients were followed up for a median duration of 52 days (longest follow-up: 3080 days). Six (6/36, 16.67%) patients continued to be in remission till the last follow-up. The hemoglobin fall was statistically significant on day three and day seven (p < 0.001 and p = 0.001) and got normalized by day 30. We observed equally good ORR in mixed populations and different phases of ITP along with long-term sustained response. The study demonstrates a quick and high response rate along with good safety profile to anti-D in all forms of ITP.

Eltrombopag in the Treatment of Immune Thrombocytopenia: Two-Center Experience from Istanbul

Immune Thrombocytopenia (ITP) is a disease caused by autoantibodies forming against platelets and T cell dysregulation and is characterized by platelet count falling below 100 × 10⁹/L. Corticosteroids remain as the first-line of treatment, but in the light of recent developments, thrombopoietin receptor agonists are gradually replacing splenectomy in steroid-dependent or refractory patients. In this study, it was aimed to retrospectively evaluate the efficacy, safety and side-effect profile of eltrombopag treatment for chronic ITP. A total of 23 chronic ITP patients treated with eltrombopag from two health institutions in Istanbul were evaluated retrospectively. Overall response rate (partial or complete) was 87%, complete response rate was 78.3%, and the median time from treatment until reaching platelet counts above 50 × 10⁹/L was 14 days (min-max: 4-126). Treatment was discontinued in four patients due to persistent response, two of these were still fully responsive. During treatment, one patient developed basal cell carcinoma, and another developed chronic myelomonocytic leukemia. Although its long-term side effects are not yet known, eltrombopag is a very effective treatment option in ITP and may provide favorable outcomes in patients.