Epidemiology, Treatment Patterns, and Cost Analysis of Immune Thrombocytopenia in Spain between 2014 and 2020: A Population-based Study.

Background Immune thrombocytopenia (ITP) is characterised by low platelet counts and often leads to bleeding, fatigue, and reduced health-related quality of life. Methods This observational, retrospective, population-based study using BIG-PAC® database included Spanish paediatric and adult patients with primary ITP diagnosed in primary care and hospitals between 2014 and 2020 (median follow-up: 4 years). Epidemiology, baseline/clinical characteristics, treatment trends, healthcare resources and costs were analysed. Results The BIG-PAC® database contains records of 1,818,588 patients; 170 adults and 27 children with ITP were included in our analysis. ITP prevalence and annual incidence per 100,000 were estimated in 10.8 (2.8 in chronic ITP [cITP] patients) and 1.5 (0.3 in cITP patients), respectively. Epistaxis was the most common bleeding event, followed by genitourinary and gastrointestinal bleeding; >50%/> 75% of ITP/cITP patients reported fatigue. Chronic patients had lower platelet counts at baseline and required more transfusions. Corticosteroids, immunosuppressants, and thrombopoietin receptor agonists were the most used agents in first-, second- and third-line treatment, respectively. Thirty-five patients, all of them in chronic phase, underwent splenectomy. Patients had on average 13.9, 6.6, and 1.2 visits/year to primary care, haematology/internal medicine, and emergency departments, respectively. More than one-fourth of adult patients took on average 16.3 days of sick leave annually. Mean annual total health care costs were €10,741 (ITP patients) and €19,809 (cITP patients). Conclusion This is the first study to provide an overall perspective on the situation of the Spanish ITP population in terms of epidemiology, treatment trends, health care resources and costs, highlighting unmet patient needs, and direct and indirect costs/resource use between 2014 and 2020.

The role of platelet desialylation as a biomarker in primary immune thrombocytopenia: mechanisms and therapeutic perspectives.

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disorder characterized by the destruction of platelets. Although it was long believed that the critical role of autoantibodies in platelet destruction, primarily through the Fc-dependent platelet clearance pathway, recent findings indicate that the significance of the Fc-independent platelet clearance pathway mediated by hepatocytes, thus shedding light on a previously obscure aspect of ITP pathogenesis. Within this context, the desialylation of platelets has emerged as a pivotal biochemical marker. Consequently, targeting platelet desialylation emerges as a novel therapeutic strategy in the pathogenesis of ITP. Notably, prevailing research has largely focused on antiplatelet antibodies and the glycosylation-associated mechanisms of platelet clearance, while comprehensive analysis of platelet desialylation remains scant. In response, we retrospectively discuss the historical progression, inducing factors, generation process, and molecular regulatory mechanisms underlying platelet desialylation in ITP pathogenesis. By systematically evaluating the most recent research findings, we contribute to a comprehensive understanding of the intricate processes involved. Moreover, our manuscript delves into the potential application of desialylation regulatory strategies in ITP therapy, heralding novel therapeutic avenues. In conclusion, this manuscript not only fills a critical void in existing literature but also paves the way for future research by establishing a systematic theoretical framework. By inspiring new research ideas and offering insights into the development of new therapeutic strategies and targeted drugs, our study is poised to significantly advance the clinical management of ITP.

New findings and new methods on macrophages in primary immune thrombocytopenia.

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disease with multiple immune cells take part in the pathogenesis. Macrophages play multiple roles in both innate and adaptive immune system. The report by Jiani Mo and colleagues identified new biomarkers and explore the role of mitophagy and ferroptosis in ITP pathogenesis. Commentary on: Mo et al. Comprehensive analysis and prediction model of mitophagy and ferroptosis in primary immune thrombocytopenia. Br J Haematol 2024;204:2429-2442.

Management of Primary Immune Thrombocytopenia - Turkish Modified Delphi-Based Consensus Statement for Special Considerations.

Introduction: Primary immune thrombocytopenia (ITP) is an acquired disorder of platelets with complex and unclear mechanism of increased immune distruction or impaired production of platelets. While management of ITP is evolving, there is a need for guidance particularly in certain circumstances such as pregnancy, emergency and for patients requiring co-medications. We aimed to determine the tendencies of hematologists in Turkiye on such special conditions. Methods: As a modified Delphi method, Turkish National ITP Working Group founded under Turkish Society of Hematology developed a questionnaire consisting of statements regarding pregnancy, emergency and circumstances regarding co-treatment with antiaggregant or anticoagulants. 107 Hematologists working either in university or state hospitals voted for their agreement or disagreement of the statements for two consequential rounds. Results: Participant hematologists reached an agreement on the starting treatment in pregnant patients with platelets less than 30 x109/L and delivery of either normal or cesarian section to be safely performed above 50 x109/L. For emergency and rescue management of ITP, our panel have agreed against the use of high dose corticosteroids alone, preferred a combination with transfusion or IVIG. For patients who require interventions, platelet counts >50 x109/L were regarded as safe for low risk procedures as well as co-treatment with antiplatelets or anticoagulants. Conclusion: As National ITP study group, we have observed the need to increase the practice guidance in patients with primary ITP requiring additional treatments including invasive interventions, and co-treatments towards coagulation. Decisions on the management of ITP during pregnancy should be individualized. There is a certain lack of consensus on the thresholds of platelet counts as well as co-morbidities and co-medications. This lack of consensus may be due to the variations in the practices.

[Efficacy and safety of eltrombopag in the treatment of primary immune thrombocytopenia: real-world data from a single medical center].

Objective: This study aimed at investigating the efficacy and safety of eltrombopag in the treatment of adult primary immune thrombocytopenia (ITP) and evaluated the factors influencing its efficacy and side effects. Methods: A total of 198 patients with adult ITP who were admitted to Tianjin Medical University General Hospital between January 2018 and March 2022 were retrospectively analyzed. The efficacy of each starting dose of eltrombopag was evaluated, and adverse events were analyzed. The factors influencing efficacy were investigated, including sex, age, adult ITP type, platelet antibodies, and combined drug treatments. Results: Of the 198 patients, 70 males and 128 females with a median age of 45 years (18-88 years) were included; 130 (65.7%) had newly diagnosed adult ITP, 25 (12.6%) had persistent adult ITP, and 43 (21.7%) had chronic adult ITP. The bleeding event scores at baseline were assessed; 84.3% had scores of<4 and 15.7% had scores of ≥4. The eltrombopag response rate (initial response) at 6 weeks was 78.8% (complete response [CR]: 49.0%; CR1: 14.6%; CR2: 15.2%). The median response time to eltrombopag was 7 (7, 14) days. The initial response rates to 25, 50, and 75 mg eltrombopag were 74.1%, 85.9%, and 60.0%, respectively (P=0.031). The initial response rate to the 50 mg dose was significantly higher than that of the 25-mg and 75-mg doses. Two patients received 100 mg as the starting dose, and their initial response was 0. Regarding dose adjustment, 70.7% of the patients remained on the starting dose, 8.6% underwent dose adjustment to 50 mg, and 6.1% underwent dose adjustment to 75 mg. Another two patients underwent dose adjustment to 100 mg. After dose adjustment, the persistent response rates were 83.6%, 85.3%, and 85.7% for the 25-, 50-, and 75-mg doses, respectively, with no significant difference. After dose adjustment, the sustained efficacy rate for the 100-mg dose (4 patients) was 100.0%. After 6 weeks of treatment with eltrombopag, the overall bleeding score of patients with ITP decreased. The number of patients with a score of ≥4 decreased to 0, the number of patients with a score of<4 decreased, and there was no significant change in the number of patients with a score of 1-2. The most common adverse event associated with eltrombopag was impaired liver function (7.7%). No thrombosis events or other adverse events were observed. ITP type and number of megakaryocytes significantly affected the initial response to eltrombopag. The initial response rates to eltrombopag for newly diagnosed adult ITP, persistent adult ITP, and chronic adult ITP were 85.3%, 56.0%, and 76.2%, respectively (P=0.003). For megakaryocytes, the initial response rates were 61.8%, 87.1%, and 84.3% (P=0.009) for the decreased, normal, and increased megakaryocyte groups, respectively. Conclusion: Eltrombopag, as a second-line or higher treatment for adult ITP, has a rapid onset of action and good safety. The initial response rate is significantly higher with a dose of 50 mg than with a dose of 25 mg. Patients with newly diagnosed ITP and those with normal or increased megakaryocyte numbers have a higher initial response rate to eltrombopag.

Challenges in treating primary immune thrombocytopenia patients undergoing COVID-19 vaccination: A retrospective study.

Background: Since the outbreak of COVID-19 in December 2019, countries around the world, including China, have been administering COVID-19 vaccines in response to the pandemic. Our center has observed that treating patients with primary immune thrombocytopenia (ITP) has become more challenging in this context. Methods: This study compared the treatment response of 25 de novo ITP patients who had received a COVID-19 vaccination (Group 1) with an equal number of de novo ITP patients randomly selected from the 2 years prior to the COVID-19 pandemic (Group 2) by using the Mann-Whitney U test and Fisher's exact. Results: Patients in both groups had predominantly female gender with similar age and baseline platelet counts. However, on Day 3, the median platelets were 22 and 49 × 109/L, and on Day 7, they were 74 and 159 × 109/L, respectively (P < 0.05). Compared to Group 2, Group 1 showed a suboptimal short-term response to glucocorticoid monotherapy, with a higher proportion of patients requiring combination therapy with other drugs including intravenous immunoglobulin, thrombopoietin receptor agonists, and rituximab. After subgroup analysis, a significant difference was observed in the proportion of patients requiring second-line therapy between the two groups. Conclusions: Our study suggests that COVID-19 vaccination may lead to a lower response rate to first-line treatment in de novo ITP patients. Nevertheless, it is crucial to acknowledge the inherent limitations in this conclusion. Further studies are needed to confirm these findings and investigate the underlying mechanisms.

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.

Distinguishing thrombotic thrombocytopenic purpura from primary immune thrombocytopenia accompanied by anemia using the carbon monoxide breath test.

OBJECTIVES: Thrombotic thrombocytopenic purpura (TTP) is a rare but life-threatening hematological disorder. Early differentiation between TTP and primary immune thrombocytopenia (ITP) accompanied by anemia is crucial to initiate an appropriate therapeutic strategy. The objective of this study was to evaluate the predictive value of red blood cell lifespan (RBCLS), determined using the carbon monoxide breath test, in the differential diagnosis of these two diseases. METHODS: We conducted a retrospective analysis of 23 patients with TTP and 32 patients with ITP accompanied by anemia. RBCLS measurements were compared and evaluated between these two patient groups. RESULTS: TTP patients had a significantly shorter mean RBCLS (20 ± 8 days) than patients with ITP accompanied by anemia (77 ± 22 days, P < 0.001) and healthy controls (114 ± 25 days, P < 0.001). In TTP patients, RBCLS showed a significant negative correlation with reticulocyte percentage and lactic dehydrogenase levels (P < 0.001). When using a standard baseline of 75 days, RBCLS demonstrated a sensitivity of 100% and specificity of 53.1% in identifying TTP. The diagnostic accuracy could reach 93% by excluding the impact of gastrointestinal bleeding. By employing the Receiver Operator Characteristics (ROC) curve, the area under the curve for RBCLS was 0.985 (95% CI: 0-1, P < 0.01) in predicting TTP, with an optimal cut-off value of 32 days, and sensitivity and specificity of 95.7% and 96.9%, respectively. CONCLUSIONS: Our study proposes a simple and accessible method for evaluating RBCLS to differentiate between TTP and ITP accompanied by anemia.

Management of Adult Primary Immune Thrombocytopenia: Delphi-Based Consensus Recommendations

Objective: Primary immune thrombocytopenia (pITP) is an acquired autoimmune disorder related to the increased destruction and/or impaired production of platelets. Its diagnosis and management are challenging and require expertise and the interpretation of international consensus reports and guidelines with national variations in availability. We aimed to assess the agreement of hematologists in Türkiye on certain aspects of both first-line and second-line management of patients with pITP. Materials and Methods: Applying a modified Delphi method, the Turkish National ITP Working Group (14 steering committee members), founded under the auspices of the Turkish Society of Hematology, developed a 21-item questionnaire consisting of statements regarding the first-line and second-line treatment of pITP. A total of 107 adult hematologists working in either university or state hospitals voted for their agreement or disagreement with the statements in two consecutive rounds. Results: The participants reached consensus on the use of corticosteroids as first-line treatment and with limited duration. Methylprednisolone was the corticosteroid of choice rather than dexamethasone. Use of intravenous immunoglobulin was not preferred for patients without bleeding. It was also agreed that thrombopoietin receptor antagonists (TPO-RAs) or rituximab should be recommended as second-line treatment and that splenectomy could be considered 12-24 months after diagnosis in patients with chronic pITP. Conclusion: The optimization of the dose and duration of TPO-RAs in addition to corticosteroids is necessary to improve the management of patients with pITP.

[Expression of MicroRNA-3162-3p in Different Clinical Stages of Children with Primary Immune Thrombocytopenia and Its Significance].

OBJECTIVE: To explore the expression of microRNA-3162-3p in different clinical stages of childhood primary immune thrombocytopenia (ITP) and its significance. METHODS: Ninety-six children with ITP were enrolled and divided into new diagnosis group (n=40), persistent group (n=30) and chronic group (n=26) according to the course of disease. 80 healthy children were selected as the control group. Peripheral blood mononuclear cells (PBMNC) of ITP children and healthy children were isolated and cultured, and the expression of microRNA-3162-3p in PBMNC of subjects was detected by real-time fluorescence quantitative PCR. The contents of IL-17, IL-23, IL-10 and TGF-ß in PBMNC of subjects were determined by ELISA. The correlation between microRNA-3162-3p and platelet count, IL-17, IL-23, IL-10 and TGF-ß was analyzed. RESULTS: Compared with the control group, the expression of microRNA-3162-3p and IL-10 in PBMNC and platelet count of ITP children were significantly decreased（P < 0.05）, while IL-17, IL-23 and TGF-ß were significantly increased (P < 0.05). With the prolongation of the disease course, the expressions of microRNA-3162-3p and IL-10 in PBMNC and platelet count were significantly decreased（P < 0.05）, while the expressions of IL-17, IL-23 and TGF-ß were significantly increased (P < 0.05). The expression of microRNA-3162-3p in PBMNC was positively correlated with platelet count and IL-10 (r =0.716, 0.667), and negatively correlated with IL-17, IL-23, and TGF-ß (r =-0.540, -0.641, -0.560). CONCLUSION: MicroRNA-3162-3p expression is significantly reduced in PBMNC of children with ITP, and is involved in the regulation of Th17/Treg imbalance, which can be used as a potential therapeutic target of ITP.

Efficacy and safety of avatrombopag in Chinese children with persistent and chronic primary immune thrombocytopenia: A multicentre observational retrospective study in China.

Avatrombopag (AVA) is a novel thrombopoietin receptor agonist (TPO-RA) that has been recently approved as a second-line therapy for immune thrombocytopenia (ITP) in adults; however, its safety and efficacy data in children are lacking. Here, we demonstrated the efficacy and safety of AVA as second-line therapy in children with ITP. A multicentre, retrospective, observational study was conducted in children with persistent or chronic ITP who did not respond to or relapsed from previous treatment and were treated with AVA for at least 12 weeks between August 2020 and December 2022. The outcomes were the responses (defined as achieving a platelet count ≥30 × 109/L, twofold increase in platelet count from baseline and absence of bleeding), including rapid response within 4 weeks, sustained response at weeks 12 and 24, bleeding control and adverse events (AEs). Thirty-four (18 males) patients with a mean age of 6.3 (range: 1.9-15.3) years were enrolled. The median number of previous treatment types was four (range: 1-6), and 41.2% patients switched from other TPO-RAs. Within 4 weeks, overall response (OR) was achieved in 79.4% patients and complete response (CR, defined as a platelet count ≥100 × 109/L and the absence of bleeding) in 67.7% patients with a median response time of 7 (range: 1-27) days. At 12 weeks, OR was achieved in 88.2%, CR in 76.5% and sustained response in 44% of patients. At 24 weeks, 22/34 (64.7%) patients who achieved a response and were followed up for 24 weeks were evaluated; 12/22 (54.55%) achieved a sustained response. During AVA therapy, median platelet counts increased by week 1 and were maintained throughout the treatment period. The proportion of patients with grade 1-3 bleeding decreased from 52.95% at baseline to 2.94% at 12 weeks, while concomitant ITP medications decreased from 36.47% at baseline to 8.82% at 12 weeks, with only 9 (26.47%) patients receiving rescue therapy 23 times within 12 weeks. There were 61.8% patients with 59 AEs: 29.8% with Common Terminology Criteria for Adverse Events grade 1 and the rest with grade 2. These findings show that AVA could achieve a rapid and sustained response in children with persistent or chronic ITP as a second-line treatment, with good clinical bleeding control and reduction of concomitant ITP therapy, without significant AEs.

Modified Sijunzi Granules Exhibit Hemostatic Effect by Activating Akt and Erk Signal Pathways via Regulating 5-HT and Its Receptors Levels.

OBJECTIVE: To investigate the hemostatic effect of modified Sijunzi Granules (MSG) in primary immune thrombocytopenia (ITP) zebrafish model and explore the potential mechanism. METHODS: AB strain wild type zebrafish were treated with simvastatin (6 µmol/L) for 24 h to establish the hemorrhage model (model control group). The zebrafish were treated with MSG at different doses (55.6, 167, and 500 µg/mL), respectively. The hemostatic effect was assessed by examining the intestinal bleeding and hemostatic rate. 5-Hydroxytryptamine (5-HT) content was determined using enzyme-linked immunosorbent assay (ELISA) assay. The expressions of 5-HT2aR, 5-HT2bR, and SERT genes were detected by quantitative real-time polymerase chain reaction(PCR). The protein expressions of protein kinase B (Akt), p-Akt, extracellular regulated protein kinases (Erk), and p-Erk were examined using Western blot analysis. RESULTS: The intestinal bleeding rate was 37%, 40%, and 80% in the 55.6, 167, and 500 µg/mL dose of MSG, respectively, in which 55.6 and 167 µg/mL MSG dose groups were associated with significantly decreased intestinal bleeding rate when compared with the model control group (70%, P<0.05). Significantly higher hemostatic rates were also observed in the 55.6 (54%) and 167 (52%) µg/mL MSG dose groups (P<0.05). MSG increased the 5-HT content and mRNA expression levels of 5-HT2aR, 5-HT2bR, and SERT (P<0.05). In addition, caspase3/7 activity was inhibited (P<0.05). Significant increase in p-Akt and p-Erk was also detected after treatment with MSG (P<0.05). CONCLUSIONS: MSG could reduce the incidence and severity of intestinal bleeding in zebrafish by activating MAPK/Erk and PI3K/Akt signal pathways through regulating the levels of 5-HT and its receptors, which may provide evidence for the treatment of ITP.

Lipoprotein lipids and apolipoproteins in primary immune thrombocytopenia: Results from a clinical characteristics and causal relationship verification, potential drug target identification by Mendelian randomization analyses.

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disease. Cellular and systemic lipid metabolism plays a significant role in the regulation of immune cell activities. However, the role of lipoprotein lipids and apolipoproteins in ITP remains elusive. The automatic biochemistry analyser was used to measure the levels of serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein A-I (apoA-I), apoB, apoE and lipoprotein a [LP(a)]. Genetic variants strongly associated with circulating lipoprotein lipids and apolipoproteins (LDL-C, apoB, TG, HDL-C and apoA-I) were extracted to perform Mendelian randomization (MR) analyses. Finally, drug-target MR and passive ITP mice model was used to investigate the potential druggable targets of ITP. Levels of HDL-C, apoA-I, decreased and LP(a) increased in ITP patients compared with healthy controls. Low HDL-C was causally associated with ITP susceptibility. Through drug-target MR and animal modelling, ABCA1 was identified as a potential target to design drugs for ITP. Our study found that lipid metabolism is related to ITP. The causative association between HDL-C and the risk of ITP was also established. The study provided new evidence of the aetiology of ITP. ABCA1 might be a potential drug target for ITP.

Quercetin, a key active ingredient of Jianpi Zishen Xiehuo Formula, suppresses M1 macrophage polarization and platelet phagocytosis by inhibiting STAT3 activation based on network pharmacology.

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease, and abnormal M1 macrophage polarization participates in the pathogenesis of ITP. Jianpi Zishen Xiehuo (JZX) Formula has a good therapeutic effect on ITP. However, its key active ingredients and molecular mechanisms remain unclear. In this study, we explored the key active ingredients and potential targets of JZX in treating ITP using network pharmacology combined with in vitro experimental verification. A total of 157 active ingredients of JZX were identified from public databases, and quercetin was the most important one. One hundred sixty-five intersection targets of active ingredients in JZX, ITP, and macrophage polarization were obtained by Venn diagram. The top three potential targets were signal transducer and activator of transcription 3 (STAT3), protein kinase B (PKB/AKT) 1, and c-JUN through protein-protein interaction analysis. Molecular docking showed that quercetin had strong binding affinities with them all. In vitro experiment, CD16+ monocytes increased in ITP patients compared with healthy controls, which indicated a M1/M2 polarization imbalance in ITP. The expression levels of M1 polarization markers, CD86, CD80, and inducible nitric oxide synthase (iNOS), M1 polarization-associated cytokines, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), and antibody-opsonized platelet phagocytosis significantly increased in THP-1 macrophages stimulated with lipopolysaccharide (LPS). Quercetin markedly inhibited the expressions of M1 markers, decreased the levels of TNF-α and IL-6, and down-regulated the phosphorylated STAT3 (p-STAT3) protein, which confirmed the prediction by network pharmacology and molecular docking. Importantly, quercetin significantly reduced the phagocytosis of antibody opsonised platelet. In conclusion, quercetin suppressed platelet phagocytosis in M1 macrophages via its anti-inflammatory effects and may serve as a potential drug for the treatment of ITP. Quercetin could be a key ingredient for JZX against ITP.

Efficacy and safety of QL0911 in adult patients with chronic primary immune thrombocytopenia: A multicenter, randomized, double-blind, placebo-controlled, phase III trial.

Objective: QL0911, a recombinant human thrombopoietin mimetic peptide-Fc fusion protein, is a romiplostim (Nplate®) biosimilar used to treat primary immune thrombocytopenia (ITP). This phase III study aimed to assess the efficacy and safety of QL0911 in adult patients with chronic primary ITP over a 24-week treatment period. Methods: We conducted a double-blind, placebo-controlled, phase III study in patients diagnosed with primary ITP for at least 12 months who had received at least one first-line ITP treatment with no response or recurrence after treatment, or who relapsed after splenectomy at 44 sites in China. Patients were randomly allocated (2:1 ratio) to QL0911 or placebo injection subcutaneously once weekly at an initial dose of 1 µg/kg for 24 weeks. The doses were adjusted to maintain the target platelet counts from 50 × 109/L to 200 × 109/L. Patients and investigators were blinded to the assignment. The primary endpoints were the proportion of patients who achieved a durable platelet response at week 24 (platelet count, ≥ 50 × 109/L during 6 of the last 8 weeks of treatment) and safety. The study was registered at ClinicalTrials.gov (NCT05621330). Results: Between October 2019 and December 2021, 216 patients were randomly assigned (QL0911,144; placebo,72). A durable platelet response was achieved by significantly more patients in the QL0911 group (61.8%, 95% CI: 53.3-69.8; P < 0.0001) than in the placebo group (0%). The mean duration of platelet responses was 15.9 (SE: 0.43) weeks with QL0911, and 1.9 (SE:0.26) week with placebo. Consistent results were achieved in subgroup analyses categorized by baseline splenectomy status (yes/no), concomitant ITP treatment (yes/no), and baseline platelet count (≤ 10 × 109/L, > 10 × 109/L, ≤ 20 × 109/L, > 20 × 109/L, and < 30 × 109/L). The incidence of TEAEs was comparable between the QL0911 and the placebo groups (91.7% and 88.9%, respectively). The most common adverse events overall were ecchymosis (28.5% for QL0911 vs. 37.5% for placebo), upper respiratory tract infections respiratory tract infections (31.9% for QL0911 vs. 27.8% for placebo), and gingival bleeding (17.4% for QL0911 vs. 26.4% for placebo). Conclusion: QL0911 was well-tolerated and increased and maintained platelet counts in adults with ITP. QL0911, a biosimilar to romiplostim (Nplate®), may be a novel treatment option for patients with ITP who have failed or relapsed from first-line treatment in China. Ongoing studies will provide further data on long-term efficacy and safety in such patient populations.

Recombinant human thrombopoietin therapy for primary immune thrombocytopenia in pregnancy: a retrospective comparative cohort study.

BACKGROUND: Treatment options for pregnant women with immune thrombocytopenia (ITP) who do not respond to first-line treatment are limited. Few studies have reported the use of recombinant human thrombopoietin (rhTPO) for this subset of patients. AIMS: To investigate the efficacy and safety of rhTPO in ITP during pregnancy and determine obstetric outcomes and predictors of treatment response. METHODS: From July 2013 to October 2022, the data of 81 pregnant women with ITP and a platelet count < 30 × 109/L who did not respond to steroids and/or intravenous immunoglobulin were retrospectively analysed. Of these patients, 33 received rhTPO treatment (rhTPO group) while 48 did not (control group). Baseline characteristics, haematological disease outcomes before delivery, obstetric outcomes, and adverse events were compared between groups. In the rhTPO group, a generalised estimating equation (GEE) was used to investigate the factors influencing the response to rhTPO treatment. RESULTS: The baseline characteristics were comparable between both groups (P > 0.05, both). Compared with controls, rhTPO patients had higher platelet counts (median [interquartile range]: 42 [21.5-67.5] vs. 25 [19-29] × 109/L, P = 0.002), lower bleeding rate (6.1% vs. 25%, P = 0.027), and lower platelet transfusion rate before delivery (57.6% vs. 97.9%, P < 0.001). Gestational weeks of delivery (37.6 [37-38.4] vs 37.1 [37-37.2] weeks, P = 0.001) were longer in the rhTPO group than in the control group. The rates of caesarean section, postpartum haemorrhage, foetal or neonatal complications, and complication types in both groups were similar (all P > 0.05). No liver or renal function impairment or thrombosis cases were observed in the rhTPO group. GEE analysis revealed that the baseline mean platelet volume (MPV) (odds ratio [OR]: 0.522, P = 0.002) and platelet-to-lymphocyte ratio (PLR) (OR: 1.214, P = 0.025) were predictors of response to rhTPO treatment. CONCLUSION: rhTPO may be an effective and safe treatment option for pregnancies with ITP that do not respond to first-line treatment; it may have slightly prolonged the gestational age of delivery. Patients with a low baseline MPV and high baseline PLR may be more responsive to rhTPO treatment. The present study serves as a foundation for future research.

Intestinal flora altered and correlated with interleukin-2/4 in patients with primary immune thrombocytopenia.

BACKGROUND: Little is known about the changes and mechanisms of intestinal flora in primary immune thrombocytopenia (ITP) patients. AIM: To explore the structural and functional differences of intestinal flora between ITP patients and healthy controls, and clarify the correlation between intestinal flora and Th1/Th2 imbalance. METHODS: Feces from ITP patients and healthy controls were studied by 16S rRNA and metagenomic techniques at phylum, genus, species or functional levels. Blood samples were collected for the detection of interleukin -2 (IL-2) and IL-4 concentrations. RESULTS: The following changes in ITP patients were found: a decrease of Bacteroidetes phylum, an increase of Proteobacteria phylum and alterations of ten genera and 1045 species. IL-2 and IL-4 were significantly correlated with six and five genera, respectively. Species of C. freundii, C. rodentium, and C. youngae were negatively correlated with bleeding scores, and S. infantis was positively related to platelet counts. Functionally, the intestinal flora of ITP patients changed mainly in terms of motility, chemotaxis, membrane transport, and metabolism. CONCLUSION: The mechanism underlying functional and structural changes of intestinal flora in ITP patients may be related to inflammation and immunity, providing possibilities of probiotics or fecal transplants for ITP.

Markers of refractory primary immune thrombocytopenia.

Refractory immune thrombocytopenia (ITP) is a challenging disease that can be defined by refractoriness to second-line treatments. In this review, we list and comment available evidence about clinical and biological factors associated with refractoriness to splenectomy, thrombopoietin receptor agonists (TPO-RAs), rituximab and fostamatinib, as well as those associated with multirefractory ITP (active disease with failure of rituximab, TPO-RAs and splenectomy).

[Expression of interleukin-37, vascular endothelial growth factor A, and transforming growth factor-ß1 and their correlation with T cells in children with primary immune thrombocytopenia]. / å„¿ç«¥åŽŸå‘å ç–«æ€§è¡€å°æ¿å‡å°‘ç—‡IL-37、VEGFA、TGF-ß1çš„è¡¨è¾¾åŠå ¶ä¸ŽTç»†èƒžçš„ç›¸å ³æ€§ç ”ç©¶.

OBJECTIVES: To investigate the expression of interleukin-37 (IL-37), vascular endothelial growth factor A (VEGFA), and transforming growth factor-ß1 (TGF-ß1) in children with primary immune thrombocytopenia (ITP) and their correlation with T cells. METHODS: A retrospective analysis was conducted on 45 children with ITP (ITP group) who were admitted to Handan Central Hospital from January 2020 to April 2022, and 30 healthy children who underwent physical examination during the same period were included as the healthy control group. The mRNA expression levels of IL-37, VEGFA, and TGF-ß1 and the levels of regulatory T cells (Treg) and helper T cells 17 (Th17) were measured before and after treatment, and the correlation between the mRNA expression levels of IL-37, VEGFA, and TGF-ß1 and the levels of Treg, Th17, and Treg/Th17 ratio were analyzed. RESULTS: Compared with the healthy control group, the ITP group had a significantly higher mRNA expression level of IL-37 and a significantly higher level of Th17 before and after treatment, as well as significantly lower mRNA expression levels of VEGFA and TGF-ß1 and significantly lower levels of Treg and Treg/Th17 ratio (P<0.05). After treatment, the ITP group had significant reductions in the mRNA expression level of IL-37 and the level of Th17 and significant increases in the mRNA expression levels of VEGFA and TGF-ß1 and the levels of Treg and Treg/Th17 ratio (P<0.05). Correlation analysis showed that in the ITP group, the mRNA expression levels of IL-37 and TGF-ß1 were negatively correlated with the levels of Treg and Treg/Th17 ratio (P<0.05) and were positively correlated with the level of Th17 (P<0.05) before and after treatment; the mRNA expression level of VEGFA was positively correlated with the levels of Treg and Treg/Th17 ratio (P<0.05) and was negatively correlated with the Th17 level (P<0.05) before and after treatment. CONCLUSIONS: Abnormal expression levels of IL-37, VEGFA, and TGF-ß1 may be observed in children with ITP, which is significantly associated with the imbalance of Treg/Th17 ratio. It is speculated that the cytokines such as IL-37, VEGFA, and TGF-ß1 may be involved in the development and progression of ITP or may become important potential targets for the treatment of children with ITP. Citation:Chinese Journal of Contemporary Pediatrics, 2023, 25(11): 1131-1136.

MST4 kinase regulates immune thrombocytopenia by phosphorylating STAT1-mediated M1 polarization of macrophages.

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disorder in which macrophages play a critical role. Mammalian sterile-20-like kinase 4 (MST4), a member of the germinal-center kinase STE20 family, has been demonstrated to be a regulator of inflammation. Whether MST4 participates in the macrophage-dependent inflammation of ITP remains elusive. The expression and function of MST4 in macrophages of ITP patients and THP-1 cells, and of a macrophage-specific Mst4-/- (Mst4ΔM/ΔM) ITP mouse model were determined. Macrophage phagocytic assays, RNA sequencing (RNA-seq) analysis, immunofluorescence analysis, coimmunoprecipitation (co-IP), mass spectrometry (MS), bioinformatics analysis, and phosphoproteomics analysis were performed to reveal the underlying mechanisms. The expression levels of the MST4 gene were elevated in the expanded M1-like macrophages of ITP patients, and this elevated expression of MST4 was restored to basal levels in patients with remission after high-dose dexamethasone treatment. The expression of the MST4 gene was significantly elevated in THP-1-derived M1 macrophages. Silencing of MST4 decreased the expression of M1 macrophage markers and cytokines, and impaired phagocytosis, which could be increased by overexpression of MST4. In a passive ITP mouse model, macrophage-specific depletion of Mst4 reduced the numbers of M1 macrophages in the spleen and peritoneal lavage fluid, attenuated the expression of M1 cytokines, and promoted the predominance of FcγRIIb in splenic macrophages, which resulted in amelioration of thrombocytopenia. Downregulation of MST4 directly inhibited STAT1 phosphorylation, which is essential for M1 polarization of macrophages. Our study elucidates a critical role for MST4 kinase in the pathology of ITP and identifies MST4 kinase as a potential therapeutic target for refractory ITP.