Refractory Immune Thrombocytopenia Patients Research Articles

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

We aimed to investigate the safety and effectiveness of eltrombopag for adult patients with refractory immune thrombocytopenia (ITP) secondary to connective tissue disease (CTD). This is a single-centre, retrospective cohort and propensity score-matched study. Data from CTD-ITP patients treated with eltrombopag between January 2019 and January 2023 were retrospectively analysed. Baseline characteristics and follow-up information were recorded. CTD patients without ITP were matched to identify the risk factors associated with CTD-ITP performed by Logistic regression analysis. Twenty patients were enrolled, including 5 systemic lupus erythematosus (SLE), 9 Sjögren's syndrome (SS) and 6 undifferentiated connective tissue disease (UCTD). Nineteen (95%) patients were female, and the median age was 59 years. Logistic regression analysis showed that anaemia (OR = 8.832, P = 0.007) was associated with increased risk of ITP, while non-erosive arthritis (OR = 0.045, P = 0.001) and interstitial lung disease (OR = 0.075, P = 0.031) were associated with reduced risk. Fourteen patients (70%) achieved a complete response (CR) and one (5%) achieved a partial response (PR). The median response time was 14 days. The median platelet count was 8.5 × 109/l at baseline of eltrombopag and increased to 122 × 109/l after 4 weeks. No adverse events were observed. Eltrombopag appears to be effective, safe and well-tolerated in refractory ITP patients with CTD; larger studies are needed to confirm the generalizability of these findings.

Efficacy and Safety of Human Umbilical Cord-Derived Mesenchymal Stem Cells in the Treatment of Immune Thrombocytopenia: A Prospective, Single Centre, Single Arm, Phase I Trial

Background Patients with refractory immune thrombocytopenia (ITP) often suffer severe bleeding events and have poor responses to various treatments. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) have been used to treat multiple autoimmune diseases due to their low immunogenicity and strong immunomodulatory potential. To explore the safety and efficacy of UC-MSCs in treating refractory ITP, we conducted this phase Ⅰ clinical trial. Methods Patients diagnosed with refractory ITP were screened for the study. The major inclusion criteria included age 18 to 60 years, ITP duration lasting for more than six months, platelet count < 30 × 10 9/L and concomitant bleeding manifestations at enrolment. The study consisted of two parts: a dose-escalation phase for exploring the safety and efficacy of three different dosage groups according to the traditional 3+3 protocol and a dose-expansion phase for further verifying the optimal UC-MSC dosage. UC-MSCs were administered at doses of 0.5×10 6 cells/kg, 1.0×10 6 cells/kg, and 2.0×10 6 cells/kg per week four times in the dose-escalation phase and 2.0×10 6 cells/kg per week four times in the dose-expansion phase. The adverse events, platelet counts, and bleeding symptoms were evaluated and recorded during the administration and follow-up period. The study protocol was approved by the Ethics Committees of the Institute of Hematology and Blood Diseases Hospital, and informed consent was obtained from each participant according to the Declaration of Helsinki (ClinicalTrials.gov ID: NCT04014166). Results Between November 2019 and August 2022, 18 refractory ITP patients hospitalized in our centre were successfully screened and enrolled in the study. Twelve patients were enrolled in the dose-escalation phase (three additional patients were added in the 2.0×10 6 cells/kg group due to the dose-limiting toxicity), and six patients were included in the dose-expansion phase. Thirteen patients (13/18, 72.2%) had one or more TEAEs. SAEs occurred in four patients (4/18, 22.2%), including gastrointestinal haemorrhage (2/4), profuse menstruation (1/4), and acute myocardial infarction (1/4). There were 0.0% (0/3), 66.7% (2/3), and 50.0% (6/12) patients in the 0.5×10 6, 1.0×10 6 and 2.0×10 6 cells/kg cohorts who achieved a response after treatment, respectively. The overall response rate was 44.4% (8/18) in all patients who received UC-MSCs. Conclusion UC-MSC infusion achieved a 44.4% overall response rate in patients with refractory ITP and mild adverse events.

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

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. 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. 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). 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.

B cells and antibodies in refractory immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an acquired bleeding disorder mediated by pathogenic autoantibodies secreted by plasma cells (PCs) in many patients. In refractory ITP patients, the persistence of splenic and bone marrow autoreactive long-lived PCs (LLPCs) may explain primary failure of rituximab and splenectomy respectively. The reactivation of autoreactive memory B cells generating new autoreactive PCs contributes to relapses after initial response to rituximab. Emerging strategies targeting B cells and PCs aim to prevent the settlement of splenic LLPCs with the combination of anti-BAFF and rituximab, to deplete autoreactive PCs with anti-CD38 antibodies, and to induce deeper B-cell depletion in tissues with novel anti-CD20 monoclonal antibodies and anti-CD19 therapies. Alternative strategies, focused on controlling autoantibody mediated effects, have also been developed, including SYK and BTK inhibitors, complement inhibitors, FcRn blockers and inhibitors of platelet desialylation.

Efficacy of phytotherapy as nutritional supplements in patients with refractory immune thrombocytopenia

IntroductionThe management of refractory immune thrombocytopenia (ITP) is challenging and difficult. The treatment was mainly comprised of cytotoxic and immunosuppressed drugs that rarely lead to long-term remission but potentially cause severe and dangerous side effects. Our current study is a retrospective clinical analysis of refractory ITP patients who underwent phytotherapy as nutritional supplements. MethodsA retrospective clinical analysis of 15 refractory immune thrombocytopenia (ITP) patients aged 12–64 with ITP history for more than 24 months before the enrollments. All patients presented with low platelet count (< 30 × 109/L) and moderate to severe bleeding symptoms such as extensive petechiae, bruising, epistaxis, prolonged menses, rectal bleeding, and hematuria. The patients underwent supportive phytotherapy as nutritional supplements using herbal extracts with hemostatic, immunomodulating, and platelet function augmenting functions ResultsThe 6-month retrospective clinical evaluation indicated that phytotherapy might offer an effective and safe solution for controlling bleeding symptoms and improving platelet counts for refractory ITP patients. Moreover, phytotherapy also significantly improved patients' red cell count, hemoglobulin, and liver enzyme levels compared to baseline data. ConclusionsIn individual cases and economically disadvantaged regions, investigating and applying an appropriate combination of phytotherapy based on scientific knowledge and traditional folk medical experiences might offer an effective, inexpensive, and safe solution for refractory ITP and other bleeding disorders.

Multi-Omics Analysis of Human Mesenchymal Stem Cell Guides Perinatal MSC Based Cellular Therapy for Splenectomy-Nonresponsive Refractory Immune Thrombocytopenia: A Phase I Clinical Trial

Mesenchymal stem cells (MSCs) are a heterogeneous population with the capacities of self-renewal, tissue regeneration and immunoregulation, which have attracted intensive attention for their potential application in the treatment of various immune disorders. However, the immunosuppressive efficacy of these therapies based on MSC products has not been thoroughly characterized, which may lead to inconsistent outcomes of MSC therapy in clinical trials. Cellular senescence is a state that imposes permanent proliferative arrest on cells in response to various types of stress and damage. Evidence suggests that aging MSCs tend to have a compromised immunosuppressive capability for inhibiting T cells. However, the underlying cellular and molecular mechanisms are poorly understood. It is also unknown whether the proportions and states of senescent cells in MSC products derived from various donors and different culture passages is associated with dissonant outcomes across clinical trials of MSC therapies. Immune thrombocytopenia (ITP) is an autoimmune disease characterized by immune-mediated destruction of circulating platelets (PLTs) and suppression of PLT production. It has been reported that autoantibody-coated PLTs undergo accelerated clearance through the spleen macrophage. However, anti-PLT antibodies are detected in less than 50% of patients, which raises the possibility of alternative mechanisms of PLT destruction. In line with this, splenectomy, which removes the primary site of PLT destruction and inhibits B-cell-mediated autoantibody production, has been shown to be the most effective therapy for steroid-refractory or steroid-dependent ITP and offers the highest rate of durable response (60% to 70%) compared with other therapies. Nevertheless, 30% to 40% of refractory ITP patients still show no response to splenectomy, indicating a B-cell-independent pathogenic mechanism. Abnormal function of T cells has been reported in ITP patients, which could collectively drive the autoimmune process. Therefore, the immune mechanism underpinning ITP should be further investigated. Additionally, it is of great value to explore new therapeutic options, such as MSC-based cellular therapy, especially for splenectomy-nonresponsive refractory ITP. Here, we performed a single-cell transcriptomic analysis of clinically used MSCs derived from adipose tissue (AD), the bone marrow (BM), the placental chorionic membrane (PM) and the umbilical cord (UC). The transcriptomic profiles of a total of 45,955 cells revealed an unprecedented level of heterogeneity in cellular senescence. We found that cultured MSCs underwent progressive cell aging, accompanied by the gradual loss of immunosuppressive function. Moreover, compared to adult MSCs (derived from AD and the BM), perinatal MSCs (derived from the PM and UC) had fewer aging cells and exhibited more potent suppressive activity. Mechanistically, we found that the impaired immunomodulatory function of senescent MSCs was associated with reduced expression of the immunosuppressive surface molecule PD-L1, which was demonstrated to be crucial for mediating the immunosuppressive activity of MSCs. Next, we performed single-cell transcriptome analysis and revealed that T-cell hyperactivation was evident in a cohort of refractory ITP patients who had no long-lasting remission after splenectomy. We therefore conducted the registered clinical trial (NCT04014166) of the use of UC-derived MSCs for refractory ITP. In this single-center, phase I trial, six refractory ITP patients received four rounds of three different doses of UC-derived MSC transfusions (0.5 × 106 MSCs/kg, n = 3; 1.0 × 106 MSCs/kg, n = 2; 2.0 × 106 MSCs/kg, n = 1). Notably, all three participants who received 1.0 × 106 or 2.0 × 106 MSCs/kg responded to the transfusions, with a manageable safety profile, while all three participants who received 0.5 × 106 MSCs/kg had no response to the transfusions. Our findings reveal the pivotal roles of cell aging and PD-L1 expression in determining the immunosuppressive efficacy of MSCs and demonstrate that PD-L1 abundant perinatal MSCs are effective in treating refractory ITP with T cell hyperactivation. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Synergistic Effect of Low-Dose Cyclosporine a on Eltrombopag (EPAG) in the Management of Prior Epag and Multiline Failed Immune Thrombocytopenia Patients: A Single-Center, Self-Control Study

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by decreased platelet (PLT) count and hemorrhagic tendency. With the development of thrombopoietin receptor agonist (TPO-RA), the prognosis of ITP who failed from first-line treatment had greatly improved. About 40-60% of patients relapse during the glucocorticoid reduction or withdrawal and require the second-line treatment. As a second-line priority recommendation, EPAG (an orally absorbable non-peptide small molecule TPO-RA) provides a sustained response in 70-80% of patients on long-term treatment for chronic ITP and 30% sustained remission rate after drug withdrawal. However, the prognostic indicators for patients who failed the initial treatment or relapsed during the treatment with EPAG are yet to be confirmed, and these may become truly refractory ITP patients in the current clinical practice. To date, only a limited number of studies have focused on how to improve the efficiency of EPAG-resistant ITP, including the novel drugs (such as fostamatinib, efgartigimod, etc.). According to the Chinese guidelines on the diagnosis and management of adult immune thrombocytopenia, immunosuppressive therapy (IST), such as cyclosporine A (CsA) and azathioprine, are recommended if patients failed the second-line treatment. However, the efficacy of mono-IST-therapy has a prolonged onset time (6-8 weeks for CsA and 7 weeks for azathioprine) and a high incidence of side effects. Currently, a few studies have reported the combination effect of EPAG with IST for refractory ITP. The total response of EAPG combined with azathioprine for refractory ITP patients was significantly higher than azathioprine alone (90.32% vs. 73.33%), but the incidence of side effects was also increased significantly, especially the hepatotoxicity (~25%). Thus, a safe and rapid response combination treatment should be explored, especially for EPAG-resistant ITP. Herein, we conducted a study to explore the efficacy and safety of EPAG combined with low-dose CsA in the management of multiline failed ITP patients who did not respond to prior EPAG single treatment. A total of 20 ITP patients who failed multiline therapies, including prior administration of 75 mg EPAG for at least 30 days were enrolled at The First Affiliated Hospital of Zhejiang Chinese Medical University (Hangzhou, China) from January 2018 to March 2022 (showed in Table). The median PLT count before treatment was 8 (2-28) ×109/L, and was associated with varying degrees of bleeding and a bleeding score of 3 (1-9). All patients continued with 50mg EPAG and received additional low-dose CsA (with a target concentration 75-120 ng/mL). 75% (15/20) patients responded to the combination treatment, and the median response time was 15 days. 73.3% (11/15) responsive patients achieved complete response (CR) during the follow-up period, 1 patient relapsed from CR due to self-reduction of EPAG and regained the response after restarting EPAG. The dose titration protocol of EPAG and CsA was shown in Figure A. No relapse was observed during the follow-up period in 15 patients with a curative effect. The median duration of platelet sustained response was 64 (18-563) days (Fig B). All patients had bleeding symptoms before treatment, and decreased to 35% (7/20) of patients after 16 weeks treatment. Among them, 85.7% (6/7) of patients presented Grade 1 bleeding (petechiae), and only 1/7 cases had Grade 2 bleeding (oral bleeding) (Fig C). During a median follow-up of 187.5 days, 70% (7/10) patients stopped or decreased the concomitant medication. Regarding side effects, only one patient suffered from venous embolic cerebral infarction, which was relieved after symptomatic treatment, and no other severe drug-related side effects were noticed during the study (total events 20%). In summary, the combination therapy of EPAG and CsA is beneficial for the quick onset and long-term efficacy maintenance, which could be a novel and effective method for the ITP patients with prior EPAG and multiline treatment failure. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Comparison of Response to Rituximab Therapy in Adults with Refractory Symptomatic Immune Thrombocytopenia According to the Presence of Accessory Spleen.

No data exist for the association between the presence of accessory spleen after splenectomy and response to rituximab in immune thrombocytopenia (ITP). We investigated the relationship between accessory spleen presence and rituximab response in splenectomized ITP patients. Fifteen chronic refractory ITP patients were included. Four weekly doses of rituximab 375 mg/m2 were administered. All patients had undergone splenectomy before rituximab administration. Accessory spleen was detected in 5 of 15 patients (33.3%). Median age at diagnosis was significantly higher in patients with accessory spleen than those without accessory spleen (40 (range 25–68 years) and 26 (range 7–40 years), respectively; p = 0.049). There was a trend for older age at time of rituximab initiation in patients with accessory spleen compared to the other group (median 51 (range 43–75 years) and 42.5 (range 30–60 years), respectively; p = 0.066). Median follow-up duration was 96 months (range 40–98). We demonstrated a significant correlation between accessory spleen presence and older age. Accessory spleen presence correlated with higher platelet and WBC counts. We showed good inverse correlation between presence of accessory spleen and time to early response (ER) to rituximab while the rate of early response (ER), late response (LR), sustained response (SR) and overall response (OR) did not differ with respect to the presence of acessory spleen.

Daratumumab As a Treatment for Adult Immune Thrombocytopenia: A Phase II Study with Safety Run-in (the DART Study)

Daratumumab As a Treatment for Adult Immune Thrombocytopenia: A Phase II Study with Safety Run-in (the DART Study)

Platelet Features from Immune Thrombocytopenia Patients Refractory to Therapeutic Treatments

Background: Immune thrombocytopenia (ITP) is an autoimmune disorder in which patients have wide variations in the number, activity and characteristics of their platelets. The goal of treatment of ITP is to raise platelet count to a level that will decrease or stop bleeding. Depending on the platelet count and the bleeding symptoms of each patient, therapeutic management is different. Pharmacological approaches employed for ITP treatment mainly aim to boost platelet count or to suppress immune system. Nevertheless, their single or combined application has been tried with a limited outcome in some ITP patients. These refractory patients constitute a clinical challenge. Identifying features of platelets from refractory ITP patients might be useful for a better understanding and management of this special clinical situation.Objective: This work aimed to determine whether platelets from refractory ITP patients have some distinguishing characteristic different from those from ITP patients responders to treatments (corticoids and thrombopoietin receptor-agonists).Methods: Citrated blood samples from 71 patients with primary chronic ITP responders to first or second line treatments and from 10 refractory ITP patients were included.Platelet surface receptors were analysed by flow cytometry (FCM, FACScan, BD Biosciences) with specific monoclonal antibodies against CD41/αIIb and CD61/β3, CD42a and CD42b.Platelet activation was assessed by FCM through PAC1-FITC binding (a mAb that recognizes activated conformation of fibrinogen receptor) after stimulation with 100 µM TRAP (agonist of the PAR-1 receptor) and with 10 µM ADP.Platelet apoptosis was analysed by FCM through FITC-annexin V (BD Pharmingen) binding to phosphatidylserine (PS) exposed on platelet membrane under basal conditions and by determination of caspases -3, -8, and -9 activities (BD Millipore).Platelet surface exposure of lectins were analyzed, respectively, with 1 µg/ml FITC-conjugated Wheat germ agglutinin lectin (WGA) or 1 µg/ml FITC-conjugated Erythrina cristagalli lectin (ECL). WGA binds to sialic acid and N-acetylglucosaminyl residues and ECL is a galactose specific legume lectin.Comparisons of quantitative variables were made with SPSS.22 software.Results: Platelets from refractory ITP patients showed a lower ability for being activated by TRAP or ADP agonists than those from ITP patients responders to treatments. Diminished responses to activation might be due to the reduced surface expression of fibrinogen receptor observed in platelets from refractory ITP patients (TABLE 1).Platelets from refractory ITP patients expressed more PS than those from responders-ITP patients under basal conditions. Moreover, platelets from refractory ITP patients showed higher activity of their caspases -3, -8 and -9 (TABLE 1).Platelets are known to contain sialic acid on glycoprotein carbohydrate side-chains. Abnormal activation of diverse sialidases causes a loss of sialic acid bound to the carbohydrate side chains of glycoproteins from platelets, leading to increased exposure of β-galactose which favors platelet capture through Ashwell-Morel receptors. This fact provides insights into the potential role of the analysis of the binding of lectins to glycoproteins of platelets from ITP patients.No differences were observed between groups for binding of ECL (responders ITP patients: 26.71±14.66, refractory ITP patients: 43.70 ± 26.16). In contrast, binding of WGA was significantly higher in the group of patients with refractory ITP (FIGURE 1).Conclusion: Platelets of refractory ITP patients had less capacity of activation by agonist stimulation and an enhanced apoptosis than platelets from ITP patients responders to treatments. Moreover, adhesion receptors expressed in their platelet surface were reduced and their glycosylation pattern seemed to differ from those of ITP patients responders to treatments. This observation poses the need of studying glycosylation processes and their consequence in platelet function and half-life.Work supported by grant from FIS-FEDER PI15/01457. NVB holds a Miguel Servet II (FIS-FEDER CP14/00024). [Display omitted] DisclosuresÁlvarez-Roman:Shire: Consultancy; Novo Nordisk: Consultancy. Jimenez-Yuste:Novo Nordisk: Consultancy, Honoraria, Research Funding; Roche: Consultancy.

Sirolimus Is Effective in Refractory Immune Thrombocytopenia: Results of an Open-Label Prospective Multicenter Trial in China

Background: Immune thrombocytopenia (ITP) is an autoimmune disease mainly due to increased destruction of platelets and decreased platelet production. Prednisone 1 mg/kg/d for 2 to 4 weeks has been the standard first-line treatment for many years. Splenectomy, rituximab and cyclosporine were commonly used second-line therapies. About 20-30% ITP patients have no response to both first-line and second-line therapies or cannot maintain the response and are diagnosed with refractory ITP. There is limited evidence for the treatment of refractory ITP. The international guideline for management of ITP suggested combined therapies but about half of the patients still fail to respond. In addition, thrombopoietin-receptor agonists are not available in China. Therefore, we investigated in alternative therapeutic options for the management refractory ITP in China.Sirolimus (rapamycin) is an immunosuppressive compound that targets the mammalian target of rapamycin (mTOR) and has been shown to induce apoptosis of both normal and abnormal lymphocytes. Recently, it has been demonstrated that treatment with sirolimus could induce complete responses (CR) in patients with corticosteroid refractory autoimmune cytopenias, including four refractory ITP patients. Based on those studies, we initiated an open-label prospective multi-institutional clinical trial (ChiCTR-ONC-17012126) using sirolimus for patients with refractory ITP in Southwest China.Methods: Refractory ITP was defined as platelet count <50 X109/L without other complications that may cause thrombocytopenia and patient has failed prednisone therapy and at least one 2nd-line therapy (prednisone + cyclosporine / splenectomy / rituximab). Sirolimus was given at a dose of 2 mg per day orally (maximum initial dose of 4 mg/day) and target a trough level of 4-15 ng/ml in circulation. The anticipated length of treatment with sirolimus was 3 months, and then taped down 0.5mg per two weeks. Patients were followed up every week for 1 year. Platelet count was measured once a week. Complete response is defined as platelet count > 100×109/L and partial response (PR) is defined as platelet count > 100×109/L or increased more than two times. Side effects were evaluated during every visit.Results: Between 01/2016 and 06/2016, 73 patients were included in the trial and 66 patients completed the trial and follow-up. In 66 patients, the median age was 47 (16-68) years; 77.3% were female; 48.5% ITP patients treated with prednisone + cyclosporine, 30.3% treated with prednisone + rituximab, 13.6% treated with prednisone + splenectomy, and 7.65% treated with prednisone + two of the four second-line treatments. Fourty-six of 66 patients responded to the therapy (30 CR and 16 PR) within 3 months of sirolimus therapy. So the response rate and CR rate are 69.7% and 45.5% respectively. In patients with CR, the median duration of platelet recovery to 100×109/L was 4 weeks (Figure 1). Risk factor analysis involving age, sex, previous treatment and platelet count before sirolimus treatment were undertaken to identify whether any factor might have an effect on the outcome of sirolimus treatment. As a result, platelet count prior to treatment was the only factor that affects the efficacy of sirolimus. During sirolimus treatment and reduction, 6 patients developed oral ulcers, 8 patients with hypertriglyceridemia, 6 patients with diarrhea and 2 patients with interstitial pneumonia. All side effects were grade 1-2 according to CTCAE 4.0.Conclusion: In summary, in our current study, more than half of the patients with refractory ITP responded to sirolimus. While the response rate is promising, there is limited evidence of side effects and long-term follow-up. Despite of this, it may worthwhile further investigations for larger scale randomized clinical trials for the evaluation of sirolimus in refractory ITP. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

CLINICAL RELEVANCE OF EXTENDED PLATELET INDICES IN THE DIAGNOSIS OF IMMUNE THROMBOCYTOPENIA.

SUMMARYImmune thrombocytopenia (ITP) is an autoimmune disorder. Besides platelet count, immature platelet fraction (IPF) can be used as a tool to predict megakaryocytic activity in ITP patients. The aim of the study was to evaluate the utility of extended platelet indices in ITP diagnosis and their association with disease persistence and severity. This case-control study (1:1), conducted from January 2015 to December 2017, included 111 ITP patients and 111 healthy controls. ITP patients were grouped as newly diagnosed ITP, persistent ITP, chronic ITP, and refractory ITP patients. Peripheral blood was collected and complete blood profile parameters were recorded using Sysmex XN 1000. Significant (p≤0.05) difference between the groups of ITP patients and healthy control subjects was determined by Fisher exact test, while Pearson correlation was used to evaluate platelet count correlation with IPF using SPSS ver. 23. Low hemoglobin and platelet counts with high total leukocyte count and IPF were detected in ITP patients as compared to healthy subjects (p≤0.001). Among all groups of ITP patients, very low platelet count (6.9±6.02.x109/L) with highest mean IPF (27.1±19.2%) was observed in newly diagnosed ITP group. Other platelet parameters including mean platelet volume (MPV), plateletcrit, platelet large cell ratio (P-LCR) and platelet distribution width values were also altered in patient groups. Pearson correlation revealed negative relationship between platelet count and IPF in all patient groups. With the advent of new, sophisticated hematologic analyzers, the IPF and other platelet parameters provide simple, reliable and easier tools for predicting platelet disorders such as ITP, and to some extent the disease severity. Besides IPF, the MPV and P-LCR seemed to predict disease severity, treatment responsiveness, and duration of the disease to some extent.

IgG-Fc glycosylation before and after rituximab treatment in immune thrombocytopenia

The interactions of antibodies with myeloid Fcγ receptors and the complement system are regulated by an Asn297-linked glycan in the Fc portion of IgG. Alterations of serum IgG-Fc glycosylation have been reported in various autoimmune diseases, and correlate with treatment response and disease activity. We hypothesized that IgG-Fc glycosylation is altered in immune thrombocytopenia (ITP) and associates with response to anti-CD20 monoclonal antibody treatment (rituximab). IgG-Fc glycosylation was analyzed by liquid chromatography-mass spectrometry. We found that IgG-Fc glycosylation was identical between refractory ITP patients (HOVON64 trial; N = 108) and healthy controls (N = 120). Two months after rituximab treatment, we observed a shift in Fc glycosylation, with a mean 1.7% reduction in galactosylation for IgG1 and IgG4 and a mean 1.5% increase for bisection in IgG1, IgG2/3 and IgG4 (adjusted p < 1.7 × 10−3 and p < 2 × 10−4, respectively). Neither baseline nor longitudinal changes in IgG-Fc glycosylation after rituximab were associated with clinical treatment response. We conclude that IgG-Fc glycosylation in refractory ITP is similar to healthy controls and does not predict treatment responses to rituximab. The observed changes two months after treatment suggest that rituximab may influence total serum IgG-Fc glycosylation. Overall, our study suggests that the pathophysiology of refractory ITP may differ from other autoimmune diseases.

A comment on "a prospective, multicenter study of low dose decitabine in adult patients with refractory immune thrombocytopenia" by Zhou et al.

We have read the article “A prospective, multicenter study of low dose decitabine in adult patients with refractory immune thrombocytopenia” by Zhou et al.1 In this prospective study, refractory immune thrombocytopenia (ITP) patients were treated with a hypomethylating agent, decitabine, which is being used as a standard of care for myelodysplastic syndrome and unfit acute myeloid leukemia patients. Though ITP has been previously treated with other immunosuppresive chemotherapeutic agents like vinctistine, cyclosporine and mycofenolate, novel agents with reasonably mild toxicity profiles were not unusual or unexpected. The study has reported promising results however we have certain doubts. First of all, as the latest three guidelines have stated, spontaneous remissions are quite unlikely in patients who have reached the 12 months’ milestone, but not impossible.2-4 In this regard, the response to decitabine might attributable to probable spontaneous remissions, not entirely, but is still debatable. Bone marrow aspiration and biopsy with chromosome analysis is recommended to all patients at this point, both to prove the diagnosis and check the cellularity and morphology. Before starting a treatment with an agent novel for this group of patients, bone marrow examination would increase the quality of the knowledge. Likewise, the detection of antiplatelet antibodies, especially against the epitopes on GP Ib and IIb/IIIa may be used, not as an initial workup but in chronic or refractory patients to support the diagnosis of ITP. But, in this study, the value of the seropositivity in terms of response to decitabine is less valuable to bone marrow examination, especially after the completion of treatment.2 Second is the status of Helicobacter pylori in refractory ITP patients. It is suggested that H. pylori should be sought and eradicated if detected in all refractory patients with noninvasive methods, like urea breathe test or stool antigen test.2, 3 Response after eradication is not uncommon and in this study, H. pylori status should have been stated to increase the homogeneity of the patients. Our last comment is the value, guides have placed on combinations. Combination of all alternatives (which have failed as monotherapies) may be used in refractory patients, including corticosteroids with thrombopoietin receptor agonists (TPO-RAs) as a dual therapy, or addition of low dose immunosuppresants.2-4 In conclusion, it is debatable that immunosuppresants towards cell cycle even with a low toxicity profile may be a reasonable approach for ITP, which has an individual pathogenesis and progress in every patient. Supporting data of the bone marrow before and after treatment as well as the failures of all suggested steps of treatments are essential.

Treatment strategy of childhood immune thrombocytopenia

Immune thrombocytopenia (ITP) of childhood is the most common hemorrhagic disease which is characterized by isolated thrombocytopenia.Depending on individual patient characteristics, appropriate initial management for newly diagnosed ITP may be either watchful waiting or pharmacologic intervention.The main options for initial pharmacologic intervention include a single dose of intravenous immune globulin(IVIG)and/or a short course of glucocorticoids.For ITP children with severe or life-threatening bleeding, it is recommended that both platelet transfusions and the combination of pharmacotherapy.Approximately 20 percent of children who present with ITP will progress to chronic ITP(CITP). Children who develop CITP should have an additional evaluation to exclude other disorders.The pharmacologic options for CITP include Rituximab, and thrombopoietin (TPO)/TPO receptor agonist (Romiplostim or Eltrombopag). Combination therapy and novel immunological targeting drugs become more effective treatment options.Splenectomy is only suit for a small number of children with chronic refractory ITP patients who present significant and persistent hemorrhagic symptoms requiring repeated pharmacologic interventions. Key words: Immune thrombocytopenia; Treatment; Child

Influence of Costimulatory Signaling Molecules on Immun Functons of B Lymphocytes in Patients with Immune Thrombocytopenia

To explore the effect of costimulatory signaling molecules (CD80, CD86) expression on the quantity and function of B lymphocytes in peripheral blood (PB) of the patients with immune thrombocytopenia (ITP). A total of 55 ITP patients (30 cases were newly diagnosed and 25 cases were in remission), 25 healthy volunteers as controls were enrolled in this study. The levels of CD19(+)CD5(+), CD19(+)CD80(+), CD19(+)CD86(+), CD41a(+)IgG, CD41a(+)IgM and IgG, IgM in CD19(+)B cells were measured by flow cytometry (FCM). The correlation of CD19(+)B cells with clinical parameters of ITP patients was analyzed. The level of B1 (CD19(+)CD5(+)) of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). The level of CD19(+)CD80(+) of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). And the expression of IgG and IgM in CD19(+)B cells of newly diagnosed ITP patients was significantly higher than that of remitted ITP patients and controls (P<0.05). The levels of IgG and IgM in remitted ITP patients after treatment were significantly lower than that before treatment (P<0.05). The level differences of IgG and IgM before and after treatment in refractory ITP patients were not statistically significant (P>0.05). The expression of CD19(+)CD80(+) in newly diagnosed ITP patients positively correlated with the level of Th1 and Th1/Th2 (r=0.502, r=0.471, P<0.05). The expression of CD19(+)CD80(+) of newly diagnosed ITP patients positively correlated with the level of IgG and IgM in CD19(+)B cells (r=0.552, r=0.467, P<0.05), and negatively correlated with PB platelet count (r= -0.424, P<0.05). The levels of IgG and IgM in CD19(+)B cells of newly diagnosed ITP patients negati- vely correlated with PB platelet count (r=-0.658, r=-0.526, P<0.05). The enhacement of costimulatory signaling pathway of CD19(+)B cells in ITP patients results in the abnormal activation of B lymphocytes, thereby mediates the dysfunction of immune system and involves in the pathogenesis of ITP.

Targeting FcγRs to treat antibody-dependent autoimmunity.

Self-reactive antibodies represent a significant force in autoimmune disease induction. In antibody-dependent autoimmune syndromes such as immune thrombocytopenia (ITP), systemic lupus erythematosus (SLE), myasthenia gravis and rheumatoid arthritis (RA), autoantibodies exert their inflammatory effect through FcγRs, a well-established class of cell surface receptors that interact with the Fc domain of IgG. Down-regulating FcγR functionality presents an attractive strategy to treat antibody-dependent autoimmune diseases. Various approaches, including nonspecific blocking of the IgG binding site as well as specific targeting using antagonistic monoclonal antibodies, have been explored to modulate the interaction between the Fc portion of IgG and FcγRs. The exquisite specificity and favorable pharmacokinetics of IgG make monoclonal antibodies a preferred choice. Indeed, the first antagonistic monoclonal antibody against the human FcγRIIIA had shown efficacy in refractory ITP patients; however, the practicality of using anti-FcγRIII antibody as a therapeutic was hindered by its associated adverse events, a phenomenon recapitulated in animal models. In this review, we discuss the role of FcγRs in autoimmune diseases, and focus on a novel monovalent approach to target FcγRs to resolve antibody-mediated autoimmunity.

Rituximab and Dexamethasone Combined with Cyclophosphamide for Treatment of Relapsed and Refractory Immune Thrombocytopenia

To evaluate the efficiency and safety of rituximab and dexamethasone combined with cyclophosphamide for treating patients with relapsed and refractory immune thrombocytopenia (ITP). Twelve patients with relapsed and refractory immune thrombocytopenia were prospectively enrolled in this study, and received rituximab 375 mg/m(2) once a week for 4 weeks, dexamethasone 40 mg once a day for consecutive 4 days, and cyclophosphamide 500 mg/m(2) biweekly for 2 weeks. The levels of IFN-r and IL-4 in peripheral blood of patients were measured by enzyme-linked immunosorbent assay (ELISA), and the percentages of Breg, Treg and Th17 cells were detected by flow cytometry before and after treatment. Efficiency was evaluated according to platelet counts, and side effects were observed. Six out of 12 patients reached to complete remission and 4 patients reached to partial remission, with the total response rate 83.33%. The platelet counts [(115.42 ± 76.60) × 10(9)/L] after treatment were significantly higher than that before treatment [(115.42 ± 76.60) × 10(9)/L] (P < 0.001). The ratio of IFN-r/ IL4 after treatment (5.89 ± 2.30) was very significantly lower than that before treatment (7.00 ± 2.73) (P = 0.002). The percentage of Breg cells after treatment [(21.27 ± 4.28)%] were much significantly higher than that before treatment [(15.48 ± 1.67)%] (P < 0.001). The ratio of Treg/Th17 after treatment (3.07 ± 1.50) was significantly higher than that before treatment (0.98 ± 0.45) (P < 0.001). Infusion reaction was observed in 1 patient, secondary hypertension and hyperglycemia were in 1 patient, and pneumonia in 2 patients. Rituximab and dexamethasone combined with cyclophosphamide can improve the outcomes of patients with relapsed and refractory immune thrombocytopenia patients and they were well tolerated, its mechanism may be related with the balance between T cell sunsets and Treg cells.

Steroid-refractory immune thrombocytopenia in the era of the new thrombomimetic drugs: is there still a role for rituximab?

TO THE EDITOR: Although corticosteroids and splenectomy represents the main therapeutic strategies [1,2] for immune thrombocytopenia (ITP), some steroid-refractory patients may be unsuitable for the surgical procedure and therefore require alternative treatment options currently available, such as rituximab [2,3] and thrombomimetic drugs [4,5]. Although rituximab is usually used in refractory ITP patients who have failed multiple previous treatments [3], its role in the era of thrombomimetic drugs represents an open question. Herein, we would like to provide our perspective on this topic in the light of our clinical experience, reporting indications to rituximab in a small series of consecutive steroid–refractory/relapsed ITP patients treated with rituximab. There were seven patients (4 male) with a median age of 38 (19-43) years. Rituximab (4 wk infusions of 375 mg/m2) was given after 50 (6–84) months from the date of ITP diagnosis. One patient suffered from active bleeding requiring platelet transfusions and was refractory to all measures, including thrombomimetic agents (eltrombopag and then romiplostim); he achieved a complete response (CR) with rituximab and was soon after splenectomized, having taken into account the high risk of recurrence and his severe bleeding tendency. Splenectomy was offered to four other patients who refused; in the remaining two patients, splenectomy as well as thrombomimetic agents were not indicated given suspected underlying autoimmune disorders and thrombophilic states. All patients who received rituximab achieved a fast response; indeed, a significant increase in platelet count was recorded early during the course of treatment: one week after the first rituximab infusion in five and after two weeks in the remaining two patients respectively. All patients maintained a sustained CR; six did not necessitate further therapy whereas one was splenectomized soon after the response to rituximab. In all patients, CR was durable and persisted after a median follow-up of 19 months (range, 6-64). No patients relapsed. Based on these findings, rituximab therapy allowed, in our experience, for long-lasting remission in patients with relapsed or refractory ITP, with a good safety profile. All patients but one, who successfully received rituximab as a bridge to splenectomy, refused or presented contraindications for the surgical procedure. Although thrombopoietin agonists, such as eltrombopag or romiplostim, in light of their high efficacy, have substantially changed the clinical scenario and the management of steroid refractory ITP [4,5], this treatment option requires prolonged administration, namely for the remainder of one's life and without a predictable suspension of therapy. Indeed, the option of a potentially life-long treatment with thrombopoietin agonists was offered to patients who refused splenectomy after a thorough explanation of the expected benefits and possible disadvantages from the therapy. The long-lasting and dependent therapy, virtually to be administered for life, was the main reason patients sought out an alternative treatment; they wanted to induce a prolonged remission of their disease without needing to depend on the therapy for life. This concern, in the setting of patients who refuse or are unsuitable for splenectomy, can allow them to find a therapy the administration of which can be predictable and carried out in limited time. This includes rituximab, the role of which is yet to be defined for selected indications even in the era of the new thrombomimetic medications.

Sustained remission of chronic immune thrombocytopenia after discontinuation of treatment with thrombopoietin-receptor agonists in adults.

Thrombopoietin-receptor agonists (TPO-RAs) are highly effective in immune thrombocytopenia (ITP). Recently, reports of sustained remission after TPO-RA discontinuation in adult ITP have been reported. We aimed to describe the subset of patients in whom TPO-RA therapy may induce a durable response. We retrospectively analyzed all of our adult ITP patients treated with TPO-RAs, and focused on patients with discontinued TPO-RA therapy due to treatment response. Forty-six relapsed or refractory ITP patients were treated with TPO-RAs. In 11 of these cases, TPO-RA therapy (seven romiplostim; four eltrombopag) was stopped after achieving treatment response. No side effects of TPO-RAs were observed. These patients were pretreated with 1-3 therapy lines plus splenectomy in six patients prior to TPO-RA administration. None of these patients experienced disease relapse after therapy discontinuation over a median follow-up of 33 months (16-54). Substantial proportion of ITP patients receiving TPO-RAs can maintain a durable response after treatment discontinuation. Sustained ITP remission probably does not depend on previous treatment, splenectomy, or disease duration.