Current and emerging treatments for immune thrombocytopenia

Association Between Idiopathic Thrombocytopenic Purpura and Hemorrhagic and Nonhemorrhagic Stroke

BACKGROUND

Idiopathic thrombocytopenic purpura (ITP) is characterized by a low platelet count. This may lead to an increased risk of hemorrhagic stroke but a lower rate of nonhemorrhagic stroke. The goal of this study was to evaluate the association between ITP and both hemorrhagic and nonhemorrhagic strokes using a large database.

METHODS

We used the Nationwide Inpatient Sample (NIS) database to analyze the occurrence of hemorrhagic and nonhemorrhagic stroke in patients with and without a diagnosis of ITP from 2005 to 2014.

RESULTS

Univariate analysis revealed a higher incidence of hemorrhagic stroke in patients with ITP in the year studied. (for example, in 2005: OR, 1.75; 95% CI, 1.57-1.94; P < 0.001; 2014: OR, 2.19; 95% CI, 2.03-2.36; P < 0.001). After adjusting for age, gender, race, and hypertension, hemorrhagic stroke remained significantly associated with ITP (in 2005: OR, 1.85; 95% CI, 1.49-1.89; P < 0.001; 2014: OR, 2.01; 95% CI, 1.86-2.18; P < 0.001) for all the years studied. Nonhemorrhagic stroke occurred at a lower rate in patients with ITP in most years (2006: OR, 0.91; 95% CI, 0.85-0.97; P = 0.004; 2014: OR, 0.88; 95% CI, 0.83-0.93; P < 0.001). Multivariate analysis confirmed a higher rate of nonhemorrhagic stroke in ITP patients.

CONCLUSION

Our analysis showed that there was a higher rate of hemorrhagic stroke but a lower rate of ischemic stroke in ITP patients, suggesting an important role of platelets in the occurrence of stroke.

Evaluation of the Effects of Atorvastatin and N-Acetyl Cysteine on Platelet Counts in Patients with Primary Immune Thrombocytopenia: An Exploratory Clinical Trial

Objective: We aimed to evaluate the efficacy of the combination of atorvastatin and N-acetyl cysteine in increasing platelet counts in patients with immune thrombocytopenia who were resistant to steroid therapy or had a relapse after treatment. Material and Methods: The patients included in this study received oral treatment of atorvastatin at a dose of 40 mg daily and N-acetyl cysteine at a dose of 400 mg every 8 h. The desired treatment duration was 12 months, but we included patients who completed at least 1 month of treatment in the analysis. The platelet counts were measured prior to the administration of the study treatment and in the first, third, sixth, and twelfth months of treatment (if available). A p value < 0.05 was considered statistically significant. Results: We included 15 patients who met our inclusion criteria. For the total treatment duration, the global response was 60% (nine patients); eight patients (53.3%) had a complete response and one patient (6.7%) had a partial response. Six patients (40%) were considered as having undergone treatment failure. Of the responder group, five patients maintained a complete response after treatment (55.5%), three patients maintained a partial response (33.3%), and one patient (11.1%) lost their response to the treatment. All of the patients in the responder group had significant increases in their platelet counts after treatment (p < 0.05). Conclusion: This study provides evidence of a possible treatment option for patients with primary immune thrombocytopenia. However, further studies are needed.

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.

Proinflammatory plasticity towards Th17 paradigm of regulatory T cells consistent with elevated prevalence of TGFBR2 variants in elderly patients with primary immune thrombocytopenia

BACKGROUND

Primary immune thrombocytopenia (ITP) is characterized for the skewed Th differentiation towards Th1 and Th17 cells as well as the impaired number and function of regulatory T cells (Tregs). Tregs are capable of co-expressing effector Th markers in different inflammatory milieu, which probably indicates Treg dysfunction and incompetence to counter over-activated immune responses.

METHODS

Ninety-two primary ITP patients from March 2013 to December 2018 were included, and proinflammatory plasticity in different Treg compartments, age groups, and TGFBR2 variant carrier status were investigated.

RESULTS

Patients were categorized into elderly (n = 44) and younger (n = 48) groups according to an age of 50 years at disease onset. The overall remission rate was 82.6% after first-line regimens, including 47.8% complete remission. TGFBR2 variants were found in 7 (7.6%) patients with three V216I and four T340M heterozygote carriers. ITP patients demonstrated elevated co-expression of IL-17 and decreased co-expression of both IFN-γ and IL-13 than health control (all p < 0.01). The elderly group demonstrated elevated prevalence of TGFBR2 variants (p = 0.037) and elevated co-expression of IL-17 (p = 0.017) in Tregs, while female predominance was found in the younger group (p = 0.037). In the elderly group, TGFBR2 variant carriers demonstrated further elevated co-expression of IL-17 (p = 0.023) and decreased co-expression of both IFN-γ (p = 0.039) and IL-13 (p = 0.046) in the aTreg compartment.

CONCLUSIONS

Our findings revealed additional aberrations of Treg proinflammatory plasticity in elderly primary ITP patients, and highlighted the potential role of Treg dysfunction and senescence in the pathogenesis and management among these patients.

Novel Therapies to Address Unmet Needs in ITP

Primary immune thrombocytopenia (ITP) is an autoimmune disorder that causes low platelet counts and subsequent bleeding risk. Although current corticosteroid-based ITP therapies are able to improve platelet counts, up to 70% of subjects with an ITP diagnosis do not achieve a sustained clinical response in the absence of treatment, thus requiring a second-line therapy option as well as additional care to prevent bleeding. Less than 40% of patients treated with thrombopoietin analogs, 60% of those treated with splenectomy, and 20% or fewer of those treated with rituximab or fostamatinib reach sustained remission in the absence of treatment. Therefore, optimizing therapeutic options for ITP management is mandatory. The pathophysiology of ITP is complex and involves several mechanisms that are apparently unrelated. These include the clearance of autoantibody-coated platelets by splenic macrophages or by the complement system, hepatic desialylated platelet destruction, and the inhibition of platelet production from megakaryocytes. The number of pathways involved may challenge treatment, but, at the same time, offer the possibility of unveiling a variety of new targets as the knowledge of the involved mechanisms progresses. The aim of this work, after revising the limitations of the current treatments, is to perform a thorough review of the mechanisms of action, pharmacokinetics/pharmacodynamics, efficacy, safety, and development stage of the novel ITP therapies under investigation. Hopefully, several of the options included herein may allow us to personalize ITP management according to the needs of each patient in the near future.

Immune Thrombocytopenia as the Initial Manifestation of Pediatric Systemic Lupus Erythematosus: Case Reports

BACKGROUND: Immune thrombocytopenia (ITP) can precede the onset of systemic lupus erythematosus (SLE) by months to years. CASE PRESENTATION: A 12-year-old girl weighing 46 kg came to the hospital with the complaint of 12 days-menstrual bleeding. The patient is weak, pale. Eyes, ENT, heart, lungs, abdomen: within normal limits, no petechiae. Laboratorium: Hemoglobin (Hb) 4.6 g/dL, leukocytes 12,930/uL, platelets 11,000/uL, hematocrit 15%, Diff Count: normal. Red blood cell (RBC) 1.59 million/uL, mean corpuscular volume (MCV) 94.3fL, mean corpuscular hemoglobin (MCH) 28.9pg, MCH concentration 30.7%, RDW-CV 14.6%. Corrected-reticulocytes 5.16%, Ret-He 22.6, IPF 54.17%. Peripheral blood smears normochromic, normocytic, blast not found, platelets are rare. The diagnosis is menometrorrhagia with anemia due to bleeding caused by ITP. The patient was given PRC and platelet transfusion, methylprednisolone. Three months later, the patient had another prolonged menstruation, hair loss, no petechiae, or purpura. Laboratorium: Hb 8.2 g/dL, leukocytes 7800/uL, platelets 6000/uL, RBC 1.59 million/uL, MCV 94.3fL, MCH 28.9pg, corrected reticulocytes 5.08%, Ret-He 24.6, IPF 54.5%. ANA test positive, Anti dsDNA-NcX 190.2 IU/ml. The diagnosis is SLE. During the last 16 months, the patient took 10 mg prednisone with a platelet count >150,000/uL. CONCLUSION: In every case of ITP in a child, consider the possibility of SLE.

Development and validation of a nomogram for steroid-resistance prediction in immune thrombocytopenia patients

OBJECTIVES

Corticosteroid is first-line therapy in immune thrombocytopenia. However, nearly 30% of patients appear in steroid-resistance. Our research analyses the relevant indicators of patients and develops a risk prediction model to predict the poor response to steroid-therapy in ITP patients.

METHODS

We collected data from 111 ITP patients admitted to Xiamen University Zhongshan Hospital from 2013 to 2019 as the training cohort and 65 ITP patients during 2019-2020 as the external validation cohort. Screening significant factors(P < 0.05) in univariate analysis, and further identified to be independent variables in multivariable logistic regression analysis. Incorporated the significant risk factors in and presented them with a nomogram based on independent risk predictors. The nomogram was assessed by receiver operating characteristics curves and decision curve analysis.

RESULTS

We constructed a steroid-resistance prediction model based on the potential predictors including age, serum ferritin and expression of HBsAg. As a result, based on the area under the ROC curves, the training cohort (AUC: 0.718, 95% CI: 0.615-0.821) and the external validation cohort (AUC:0.799,95%CI:0.692-0.905), which displayed good discrimination. The decision curve showed that predicting the steroid-refractory risk in ITP patients using this nomogram with a range of the threshold probability between >16% and <70%. The nomogram appears good performance in predicting steroid-refractory ITP patients.

CONCLUSION

Prediction model shows that elder patients with a high level of ferritin and positive expression of HBsAg may appear a high possibility of steroid-resistance. For these patients, TPO-RAs can be considered to help patients to get better treatment effects and develop a better health-related quality of life.

New treatments for primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is an autoimmune disease leading to a decreased platelet count and an ensuing haemorrhagic risk. First-line treatment against ITP consists in the administration of immunomodulators aimed at decreasing platelet destruction. Up to 70% of individuals with an ITP diagnosis treated with corticosteroids do not achieve a clinical response or demonstrate a high relapse rate, requiring treatment to prevent a haemorrhagic risk. Less than 30% of patients treated with thrombopoietin analogues, 60% of those treated with splenectomy and 20% of those treated with rituximab reach sustained remission in the absence of treatment. Because of these reasons, it is unquestionable that treatment of patients with ITP should be optimized. Through this study, we will review new actual and future options of treatment.

Secondary Dysgammaglobulinemia in Children with Hematological Malignancies Treated with Targeted Therapies

Targeted therapies have emerged as innovative treatments for patients whose disease does not respond to conventional chemotherapy, and their use has widely expanded in the field of pediatric hematologic malignancies in the last decade. While they carry the promise of improved disease control and survival and are currently investigated in first-line treatment protocols for patients with poor prognostic markers, they are associated with a considerable incidence of specific toxicities, including cytokine-release syndrome, neurotoxicity, hepatotoxicity, nephrotoxicity, cardiotoxicity, endocrine adverse events, and infectious complications. Iatrogenic or secondary dysgammaglobulinemia is a main consequence of targeted therapies using monoclonal antibodies and other antibody-derived treatments that target specific antigens on lymphoid cells (blinatumomab, inotuzumab ozogamicin, rituximab), chimeric antigen receptor T cells, tyrosine kinase inhibitors (imatinib, dasatinib, nilotinib) and, to a lesser extent, checkpoint inhibitors (pembrolizumab, nivolumab). This review discusses the diagnosis and incidence of secondary or iatrogenic dysgammaglobulinemia in children treated with targeted therapies for leukemias and lymphomas, and options for monitoring and treatment.

Update on diagnosis and treatment of immune thrombocytopenia

BACKGROUND

Immune thrombocytopenia (ITP) is a heterogeneous acquired disorder characterized by isolated thrombocytopenia whose exact pathogenesis is not yet clear. Depending upon the presence or absence of an underlying treatable cause, ITP can be categorized as primary or secondary. Primary ITP is a diagnosis of exclusion and there is no gold standard test for its confirmation. Recent drug intake, infections, lymphoproliferative disorders, and connective tissue disorders should be ruled out before labeling a patient as primary ITP.

AREA COVERED

This review summarizes a comprehensive update on the diagnostic and therapeutic modalities for ITP. We reviewed the literature using GOOGLE SCHOLAR, PUBMED and ClinicalTrial.gov databases as needed to support the evidence. We searched the literature using the following keywords: 'immune thrombocytopenia,' 'idiopathic thrombocytopenic purpura,' 'thrombocytopenia,' 'immune thrombocytopenic purpura,' and 'isolated thrombocytopenia'.

EXPERT OPINION

We believe that more detailed studies are required to understand the exact pathophysiology behind ITP. The first-line drugs like corticosteroids have both short-term and long-term adverse effects. This brings the need to explore effective alternative medications and to reconsider their role in ITP treatment algorithm if guidelines can be modified based on new studies.

Risk Factors and Psychological Analysis of Chronic Immune Thrombocytopenia in Children

OBJECTIVE

To study the risk factors and psychological changes in children with chronic immune thrombocytopenia (CITP).

METHODS

This was a retrospective analysis of 234 children with ITP diagnosed and treated in the Affiliated Hospital of Southwest Medical University from January 2016 to December 2018. The clinical characteristics and related laboratory factors of all patients were collected, and their impact on the chronicity of ITP was analyzed. The Eysenck Personality Questionnaire-Children's Version (7-15 years old) is a psychological assessment of children with chronic ITP (CITP).

RESULTS

Univariate analysis found that the course of the initial diagnosis (χ2 =6.879, P<0.05), the age of onset (χ2 =13.846, P<0.05) and the absolute value of the initial diagnosis of peripheral blood lymphocytes (χ2 =6.436, P<0.05) had statistical differences in the chronicity of ITP in children; a multivariate analysis of the course of the first diagnosis, the age of onset and absolute lymphocyte count (ALC) revealed that ALC is an independent factor in children's chronic ITP (P<0.05). Compared with normal children, children with CITP had statistical significance in extraversion (t=-3.476, P<0.05); compared with newly diagnosed children, they had statistical significance in extraversion (E) and lying (L) (P<0.05); and there was no statistical difference compared with persistent children (P>0.05).

CONCLUSION

The age of onset, the absolute value of lymphocytes at the initial diagnosis, and the course of the initial diagnosis are important for predicting the chronicity of ITP in children. ALC is an independent predictor; children with chronic ITP have psychological problems.