Management of immune thrombocytopenia: 2022 update of Korean experts recommendations

The immune thrombocytopenia paradox: Should we be concerned about thrombosis in ITP?

Despite the predisposition to bleeding, patients with immune thrombocytopenia (ITP) may also have an increased risk of arterial and venous thrombosis, which can contribute to significant morbidity. The risk of thrombosis increases with age and the presence of cardiovascular risk factors. This narrative review explores the multifactorial nature of thrombosis in ITP, focusing on new pathological mechanisms, emerging evidence on the association between established treatments and thrombotic risk, the role of novel treatment approaches, and the challenges in assessing the balance between bleeding and thrombosis in ITP. The review also explores the challenges in managing acute thrombotic events in ITP, since the platelet count does not always reliably predict either the risk of bleeding or thrombosis and antithrombotic strategies lack specific guidelines for ITP. Notably, second-line therapeutic options, such as splenectomy and thrombopoietin receptor agonists (TPO-RAs), exhibit an increased risk of thrombosis especially in older individuals or those with multiple thrombotic risk factors or previous thrombosis, emphasizing the importance of careful risk assessment before treatment selection. In this context, it is important to consider second-line therapies such as rituximab and other immunosuppressive agents, dapsone and fostamatinib, which are not associated with increased thrombotic risk. In particular, fostamatinib, an oral spleen tyrosine kinase inhibitor, has promisingly low thrombotic risk. During the current era of the emergence of several novel ITP therapies that do not pose additional risks for thrombosis, it is critical to outline evidence-based strategies for the prevention and treatment of thrombosis in ITP patients.

Cost-utility analysis of romiplostim for the treatment of chronic primary immune thrombocytopenia in China

This study aimed to assess the cost-utility of romiplostim (ROMI) compared to eltrombopag (EPAG) as a second-line treatment for chronic primary immune thrombocytopenia (cITP) in Chinese adults. A decision tree-embedded Markov model with a lifetime horizon was used to estimate the quality-adjusted life years (QALYs) and costs for ROMI versus EPAG from the perspective of the Chinese health care system. The model was driven by platelet response with a 4-week cycle. Both QALYs and costs were discounted 5% per year. Clinical data comparing ROMI and EPAG were obtained by matching-adjusted indirect comparison (MAIC), utilizing individual patient data on ROMI and published Chinese Phase III trial data on EPAG. Costs were reported in 2022 US dollars and included drug acquisition costs, monitoring costs, bleeding-related costs, and costs associated with adverse events. Deterministic and probabilistic sensitivity analyses were performed. The CEA model indicated that treatment with ROMI resulted in an average of $4,344.4 higher costs for 0.004 QALYs. One-way sensitivity analysis (OSA) indicated that the model was most sensitive to the high bleeding rate in response (Markov stage) for EPAG and ROMI. Probabilistic sensitivity analysis (PSA) indicated that ROMI was likely to be cost effective in 0.16% cases at a willingness-to-pay threshold of $12039.1 (China per capita GDP in 2022) per QALY. If the price of ROMI is either lower than or equal to that of EPAG, ROMI could likely be considered cost-effective as a second-line treatment for Chinese adults with cITP.

The many facets of immune-mediated thrombocytopenia: Principles of immunobiology and immunotherapy

Immune thrombocytopenia (ITP) is a rare autoimmune condition, due to peripheral platelet destruction through antibody-dependent cellular phagocytosis, complement-dependent cytotoxicity, cytotoxic T lymphocyte-mediated cytotoxicity, and megakaryopoiesis alteration. This condition may be idiopathic or triggered by drugs, vaccines, infections, cancers, autoimmune disorders and systemic diseases. Recent advances in our understanding of ITP immunobiology support the idea that other forms of thrombocytopenia, for instance, occurring after immunotherapy or cellular therapies, may share a common pathophysiology with possible therapeutic implications. If a decent pipeline of old and new agents is currently deployed for classical ITP, in other more complex immune-mediated thrombocytopenic disorders, clinical management is less harmonized and would deserve further prospective investigations. Here, we seek to provide a fresh overview of pathophysiology and current therapeutical algorithms for adult patients affected by this disorder with specific insights into poorly codified scenarios, including refractory ITP and post-immunotherapy/cellular therapy immune-mediated thrombocytopenia.

Patient preferences and experiences regarding thrombopoietin-receptor agonists for immune thrombocytopenia in The Netherlands (TRAPeze Netherlands study)

OBJECTIVE

Identify patient experience and preference towards thrombopoietin-receptor agonists (TPO-RAs) in treatment of immune thrombocytopenia (ITP) in the Netherlands.

METHODS

The Thrombopoietin-Receptor Agonist Patient experience (TRAPeze) survey used a discrete choice experiment (DCE) to elicit patient preferences and a patient burden survey (PBS) to evaluate the clinical and social impact of ITP. TRAPeze collected responses from 6th October to 19th November 2021.

RESULTS

Seventy-six respondents completed the DCE: treatment preference appeared to be driven by method of administration (odds ratio [OR] 4.33; 95% confidence interval [CI] 2.88-6.52), frequency of dosing (OR 2.33; 95% CI 1.86-2.92) and drug-food interactions (OR 1.91; 95% CI 1.54-2.37). Respondents preferred therapies delivered orally over subcutaneous injection (OR 4.22; 95% CI 2.76-6.46), dosed once weekly over once daily (OR 2.37; 95% CI 1.58-3.54) and without food restrictions over with restrictions (OR 1.90; 95% CI 1.52-2.38). Sixty-nine respondents completed the DCE and PBS (mean [range] age 53 [19-83] years, 65% female). Seven incomplete PBS responses were excluded from analysis. Respondents were currently, or most recently, receiving eltrombopag (n = 43) or romiplostim (n = 26), of which 30% (n = 21/69) had previously received another TPO-RA. Loss (29%, n = 6/21) and lack (29%, n = 6/21) of response were the most common reasons for switching TPO-RA. Only 28% (n = 18/65) of respondents felt their TPO-RA increased energy levels.

CONCLUSION

Patients preferred therapies delivered orally, dosed less frequently and without food restrictions. QoL of ITP patients on TPO-RAs can be improved; the burden analyses presented can inform future efforts towards this.

Idiopathic Thrombocytopenic Purpura: Current Limitations and Management

Idiopathic thrombocytopenic purpura (ITP), also known as immune thrombocytopenia, is a blood disorder characterized by a reduction in the number of platelets. A reduction in the number of platelets beyond the normal levels leads to several consequences. A severe reduction in blood platelet levels leads to a rash of purple spots on the skin, joints, etc. due to leakage in the small blood vessels, easy bruising, bleeding gums, intestinal bleeding, and hemorrhage. Suppose a case of ITP resolves in fewer than six months. In that case, it is an acute case of ITP. Still, if a case settles in more than six months, it is a case of ITP. The cause of a reduced platelet count can be increased peripheral destruction or impaired production; this is termed an autoimmune condition in which the body's immune system attacks platelets thinking it to be a foreign antigen. ITP in children occurs commonly following a previous viral attack. Even though evaluating patients' reports is useful for understanding and guiding the treatment, these estimates might not be regularly evaluated in clinical settings. First-line drugs in the treatment of ITP are corticosteroids, and long-term use of these drugs has several side effects, such as excessive increase in weight, mental health disturbances, and sleep disturbances; additional therapies to treat hemorrhage are usually momentary. As a result, it is essential to recognize the flaws in current procedures and adopt innovative measures for the management and minimization of difficulties.

Siblings With Thrombocytopenia Found To Have a Pathogenic Variant in the NFkB1 Gene

Immune thrombocytopenic purpura is one of the most common causes of low platelet count in the pediatric population. Secondary thrombocytopenia has a wide differential diagnosis in children, including rheumatological, hematological, and immunological etiologies. Underlying etiologies must be excluded if suspected before labeling the patient as primary thrombocytopenia. Here, we report two siblings with persistent and profound thrombocytopenia. A 10-year-old girl presented with profound and treatment-refractory thrombocytopenia. Given the patient's family history of thrombocytopenia of unknown pathology in her older brother, immune dysregulation-related thrombocytopenia was suspected. Whole exome sequencing confirmed a previously reported pathogenic variant in the NFKB1 gene linked to common variable immunodeficiency 12 (CVID-12) diagnosis for both patients.

Is splenectomy a good strategy for refractory immune thrombocytopenia in adults?

Rituximab and thrombopoietin receptor agonists (TPO-RAs) have profoundly changed the management of immune thrombocytopenia (ITP) over the last 20 years. Even if most current guidelines put splenectomy, rituximab and TPO-RAs on the same treatment level, most clinicians and patients clearly prefer to postpone splenectomy and to multiply the lines of medical treatment before considering surgery. The management of ITP refractory to rituximab and TPO-RAs is challenging. Splenectomy is currently performed much less frequently because of a better knowledge of its complications, particularly severe late infections and deep vein thrombosis, and the inability to reliably predict its effectiveness. Furthermore, there is a reluctance to propose splenectomy when other treatments have been ineffective, based on the not well-documented risk that splenectomy could not be effective in such a case. The objective of this update was to review the most recent published data on the long-term tolerability and side effects of splenectomy and the predictors of response and efficacy, especially for patients exposed to multiple medical lines. This update can help physicians and patients with failure of multiple lines of therapy make an informed decision on the indication for splenectomy with the help of up-to-date data.

Eradication therapy may decrease the risk of immune thrombocytopenia after Helicobacter pylori infection: a retrospective cohort study in Taiwan

BACKGROUND

Helicobacter pylori (HP) eradication therapy (HPE) is recommended for patients with unexplained immune thrombocytopenia (ITP); however, the role of HPE in preventing ITP in patients with HP infection remains unclear. Therefore, this study was designed to clarify it.

METHODS

This study was conducted at a tertiary medical center and included all adult patients with HP infection between January 1, 2016 and December 31, 2018. We compared the risk of developing ITP between patients with and without HPE. All patients were followed up until December 31, 2020.

RESULTS

After excluding patients with thrombocytopenia, 1995 adult patients with HP infection, including 1188 patients with HPE and 807 patients without HPE, were included in this study. The mean age of the patients with HPE was 57.9 years, whereas that of those without HPE was 61.6 years. The percentage of males was 56% in patients with HPE and 59% in those without HPE. Patients without HPE had a higher risk of ITP than those with HPE after adjusting for age, sex, the Charlson Comorbidity Index, and comorbidities [adjusted odds ratio (OR) 1.76; 95% confidence interval (CI) 1.16-2.68]. Stratified analyses showed that the higher risk was found only in males (adjusted OR: 1.70; 95% CI 1.03-2.80). In addition to HPE, male sex and anemia were independent predictors of ITP in patients with HP infection.

CONCLUSION

This study showed that adult patients with HP infection not receiving HPE had a higher risk of developing ITP. We suggest that HPE should be considered, particularly in males and those who have anemia, to prevent ITP.

Recent advances in treatments of adult immune thrombocytopenia

Immune thrombocytopenia (ITP) is isolated thrombocytopenia characterized by autoimmune-mediated disruption of platelet without other etiologies. Treatments for chronic ITP consist of corticosteroids, intravenous immunoglobulins, anti-D immunoglobulin, rituximab, thrombopoietin receptor agonists, immunosuppressants and splenectomy. Although current therapies are effective in over two-thirds of patients, some patients are refractory to therapies or fail to achieve long-term responses. Recently, great advance has been made in identifying various mechanisms involved in ITP pathogenesis, and new treatments targeting these pathways are being developed. Novel agents such as splenic tyrosine kinase inhibitor, Bruton kinase inhibitor, plasma cell targeting therapies, neonatal Fc receptor inhibitor, platelet desialylation inhibitor, and inhibition of the classical complement pathway are expected to be effective for ITP treatment. This review summarizes current strategies and emerging therapies of ITP.