Impact of risk factors on the occurrence of arterial thrombosis and venous thromboembolism in adults with primary immune thrombocytopenia – Results from two nationwide cohorts

The impact of Mycoplasma pneumoniae infection on platelets in children with immune thrombocytopenia: a real-world study from China

Mycoplasma pneumoniae (M. pneumoniae), as one of the susceptible pathogens during childhood, may lead to severe mycoplasmal pneumonia and affect platelet fluctuations. We prospectively collected data on persistent/chronic ITP children who were infected with M. pneumoniae infection from August 2023 to December 2023. There were 64 patients (40 males) with a median age of 7.08 years (range 4.30 to 9.76) enrolled in this study. Overall, 33 (51.6%) children received TPO-RAs therapy and 31 (48.4%) received other treatments. The impact of M. pneumoniae infection on platelet count is bidirectional, but thrombocytopenia remains predominant. During M. pneumoniae infection, platelet changes in the TPO-RA group were higher than in the non-TPO-RA group. Thrombocytosis was observed in 6 patients (5 in the TPO-RA group vs. 1 in the non-TPO-RA group). Rescue treatment was implemented in 18 patients (7 in the TPO-RA group vs. 11 in the non-TPO-RA group). Monitoring platelets should be strengthened during M. pneumoniae infection.

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.

Post-marketing safety surveillance of fostamatinib: an observational, pharmacovigilance study leveraging FAERS database

OBJECTIVE

Fostamatinib, an FDA-approved oral small-molecule spleen tyrosine kinase (SYK) inhibitor, is used to treat thrombocytopenia in adults with chronic immune thrombocytopenia (ITP) who have not responded to previous treatments. However, comprehensive safety data is lacking. This study uses the FDA Adverse Event Reporting System (FAERS) database to explore real-world adverse events (AEs) related to fostamatinib, aiming to inform its clinical use.

METHODS

The FAERS database was retrospectively queried to extract reports associated with fostamatinib from 2019 to 2023. To identify and evaluate potential AEs in patients receiving fostamatinib, various disproportionality analyses such as the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) were employed.

RESULTS

A total of 23 AE signals were included in our analysis. Among them, hypertension, blood pressure increase, blood pressure abnormality, hepatic enzyme increase, and diarrhea were consistent with the common AEs described for fostamatinib in clinical trials. In addition, unexpected serious AEs were detected including cerebral thrombosis and necrotizing soft tissue infection. The median time to onset of fostamatinib-related AEs was 86 days.

CONCLUSION

Our investigation revealed several possibly emergent safety concerns associated with fostamatinib in real-world clinical practice, which might provide essential vigilance evidence for clinicians and pharmacists to manage the safety issues of fostamatinib.

Risk-based and individualised management of bleeding and thrombotic events in adults with primary immune thrombocytopenia (ITP)

Although bleeding is one of the main symptoms of primary immune thrombocytopenia (ITP), risk factors for bleeding have yet to be fully established. Low platelet count (PC; <20-30 × 109 /L) is generally indicative of increased risk of bleeding. However, PC and bleeding events cannot be fully correlated; many other patient- and disease-related factors are thought to contribute to increased bleeding risk. Furthermore, even though ITP patients have thrombocytopenia and are at increased risk of bleeding, ITP also carries higher risk of thrombotic events. Factors like older age and certain ITP treatments are associated with increased thrombotic risk. Women's health in ITP requires particular attention concerning haemorrhagic and thrombotic complications. Management of bleeding/thrombotic risk, and eventually antithrombotic therapies in ITP patients, should be based on individual risk profiles, using a tailored, patient-centric approach. Currently, evidence-based recommendations and validated tools are lacking to support decision-making and help clinicians weigh risk of bleeding against thrombosis. Moreover, evidence is lacking about optimal PC for achieving haemostasis in invasive procedures settings. Further research is needed to fully define risk factors for each event, enabling development of comprehensive risk stratification approaches. This review discusses risk-based and individualised management of bleeding and thrombosis risk in adults with primary ITP.

Thrombosis in patients with immune thrombocytopenia: incidence, risk, and clinical outcomes

Background

There is evidence that patients with immune thrombocytopenia (ITP) are at increased risk of thrombosis. However, the association of clinical- and treatment-related factors with thrombosis remains controversial.

Objectives

To evaluate the incidence and impact of risk factors for arterial and venous thromboembolism (VTE) in patients with ITP and characterize the clinical features and management of patients.

Methods

We performed a retrospective cohort study (January 1, 2011, to October 30, 2022) of adult patients diagnosed with ITP from an Australian tertiary hospital. The incidence rates of thrombosis were calculated in terms of person-years of follow-up. Multiadjusted Cox regression was used to estimate associations.

Results

A total of 220 patients with 1365 person-years of follow-up since ITP diagnosis revealed 26 (11.8%) patients with a total of 37 thrombosis events, 29 (78%) VTE and 8 (22%) arterial thromboembolism (ATE). The incidence rate of thrombosis was 2.71 (95% CI, 1.97-3.72) (0.66 [95% CI, 0.33-1.26] for arterial thromboembolism and 2.05 [95% CI, 1.42-2.95] for VTE) per 100 person-years. Mean age and median time to first thrombosis diagnosis was 56 and 2.13 years, respectively. Age, secondary ITP, lines of therapy, thrombosis risk factors, and thrombopoietin receptor agonist therapy were independently associated with thrombosis. Almost all patients (25 of 26, [96%]) had good ITP disease control prior to thrombosis diagnosis, and antithrombotic therapy was deliverable and well tolerated.

Conclusion

Diagnosis of thrombosis in patients with ITP, while infrequent, is of clinical significance. We identified from a heterogeneous real-world cohort that older patients with multiply-treated secondary ITP receiving thrombopoietin receptor agonists are at the highest risk.

Risk of thrombotic events in immune thrombocytopenia patients treated with thrombopoietic agents: a systematic review and meta-analysis

BACKGROUND

Immune thrombocytopenia (ITP), which is a well-known hemorrhagic disorder characterized by low platelet counts, has been shown to be associated with the risk of thrombosis. Thrombopoietic agents (TAs) are extensively used as second-line treatments for ITP, effectively reducing the risk of hemorrhage. However, thrombosis, a potential adverse effect of TAs, raises clinical challenges.

METHODS

The MEDLINE(PubMed), Embase, and the Cochrane Library databases were systematically searched for relevant studies, including both single-arm trials and randomized controlled trials (RCTs), without language restrictions.

RESULTS

A total of 17 RCTs comprising 2,105 patients and 29 single-arm trials comprising 3,227 patients were included. In the single-arm meta-analysis, the pooled rate of overall thrombotic events in ITP patients receiving TAs was 2.2% (95% CI 1.0% - 3.7%). In RCTs, a higher incidence of thrombosis (33/1425 vs. 4/680) and higher risk ratios (RR) of overall, arterial, and venous thrombotic events (1.73, 95% CI [0.88, 3.39], P = 0.113; RR 1.98, 95% CI [0.80, 4.92], P = 0.141; RR 1.06, 95% CI [0.46, 2.41], P = 0.895, respectively) were observed in the TAs group than in the control group, although the differences were not significant. Subgroup analysis demonstrated that hetrombopag was the only TA with no increased thrombotic risk (rate 0.3% 95% CI [0.0 - 1.5%]; RR 0.76, 95% CI [0.03, 18.41], P = 0.864) compared to eltrombopag, avatrombopag, romiplostim, and rhTPO. Subgroup analyses also revealed that ITP patients with advanced age (3.7% vs. 1.3%, P = 0.132) or with a thrombotic history (3.0% vs. 1.4%, P = 0.257), and patients who received TAs therapy for a long duration (4.7% vs. 0.1%, P < 0.001) had an increased risk of thrombosis.

CONCLUSION

Our findings suggest ITP patients treated with TAs have a nonsignificantly higher risk of overall, arterial, and venous thrombotic events. Furthermore, hetrombopag is the recommended TA to avoid thrombophilia. Patients receiving long-term TAs, as well as elderly ITP patients or those with a history of thrombosis, face an increased thrombotic risk. In general, clinicians should consider potential thrombotic risks, address underlying risk factors, and ensure ongoing monitoring and follow-up when treating ITP patients with TAs.

An obvious antinomy, superior sagittal sinus thrombosis in a patient with immune thrombocytopenia: Case report and a review of literatures

RATIONALE

Immune thrombocytopenia (ITP) is an autoimmune disease with an increased risk of bleeding. However, in recent years, it has been reported that patients with this hemorrhagic disease have the risk of thrombosis and embolism.

PATIENT CONCERNS AND DIAGNOSIS

The patient, in this case, was a young female who was diagnosed with ITP. When the platelet count was low, she had skin, mucosa, internal organs, and intracranial hemorrhage. In the process of ITP and hemostatic treatment, superior sagittal sinus thrombosis occurred when she was still bleeding.

INTERVENTIONS

She was given treatments for reducing intracranial pressure and controlling epilepsy.

OUTCOMES

And then the embolectomy operation failed. It was suggested in this case that ITP patients with severe thrombocytopenia and bleeding tendency also have a risk of having thrombotic disease. We reviewed literatures regarding the mechanism of the simultaneous occurrence of 2 antinomy diseases and cerebral venous thrombosis.

LESSONS

There are many factors for ITP patients to have thrombosis involving ITP itself, its treatment and the patients' constitution, medical history, and former medication. ITP is not only a hemorrhagic disease but also a thrombotic disease. Clinicians should be alert to the risk of thrombotic diseases in ITP treatment. Therefore thrombus monitoring and screening should be carried out, and early prevention or appropriate anticoagulant treatment should be selected, especially for patients with high risk.

Older Adults and Immune Thrombocytopenia: Considerations for the Clinician

Many epidemiological studies have shown that the incidence of immune thrombocytopenia (ITP) increases after age 60 years and peaks in patients over age 80 years. Therefore, ITP is a concern for physicians taking care of older patients, especially regarding its diagnosis and management. The diagnostic work-up should exclude other causes of thrombocytopenia and secondary ITP, including myelodysplastic syndrome and drug-induced ITP. The treatment decision is influenced by an increased risk of bleeding, infectious diseases and thrombosis in this population and should take into account comorbidities and concomitant medications such as anticoagulant drugs. First-line treatment is based on short corticosteroids courses and intravenous immunoglobulin, which should be reserved for patients with more severe bleeding complications, with their higher risk of toxic effects as compared with younger patients. Second-line treatment should be tailored to the patient's history, comorbidities and preferences. Preferred second-line treatments are thrombopoietin receptor agonists for most groups and guidelines given their good efficacy/tolerance ratio, but the thrombotic risk is increased in older people. Other second-line options that can be good alternatives depending on the clinical context include rituximab, dapsone, fostamatinib or immunosuppressive drugs. Splenectomy is less often performed but remains an option for fit patients with chronic refractory disease. Emerging treatments such as Syk or Bruton tyrosine kinase inhibitors and FcRn antagonists are becoming available for ITP and may modify the treatment algorithm in the near future. The aim of this review is to describe the particularities of the diagnosis and treatment of ITP in older people, including the response and tolerance to the currently available drugs. We also discuss some situations related to co-morbidities that can frequently lead to adapt the management strategy in older patients.

Thrombosis and thromboembolism: Brighton collaboration case definition and guidelines for data collection, analysis, and presentation of immunization safety data

This is a Brighton Collaboration case definition of thrombosis and thromboembolism to be used in the evaluation of adverse events following immunization, and for epidemiologic studies for the assessment of background incidence or hypothesis testing. The case definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of SARS-CoV-2 vaccines. The case definition format of the Brighton Collaboration was followed to develop a consensus definition and defined levels of certainty, after an exhaustive review of the literature and expert consultation. The document underwent peer review by the Brighton Collaboration Network and by selected expert reviewers prior to submission.

Risk factors and characteristics of ischemic stroke in patients with immune thrombocytopenia: A retrospective cohort study

OBJECTIVES

Previous research has found that patients with immune thrombocytopenia (ITP) have an increased risk of thrombosis, such as venous thromboembolism (VT), ischemic stroke (IS)/transient ischemic attack (TIA), and cardiovascular disease (CVD), but the risk factors for stroke in patients with ITP have yet to be determined. This study aims to determine the risk factors and characteristics of ischemic stroke in patients with ITP.

MATERIALS AND METHODS

This study included adults with incident primary ITP diagnosed in a tertiary medical center between 2010 and 2020. The t-test and Mann-Whitney U test were used to compare the variables between IS and non-IS groups, and the multivariate logistic regression model was employed to evaluate correlations.

RESULTS

The study enrolled 1824 individuals, of whom 17 (0.93%) had IS, and 138 (1:8) were randomly chosen from 1807 non-IS patients. Age was found to be substantially associated with stroke in the multivariate analysis (OR 1.07, 95% CI: 1.026-1.116; p = 0.001). We found no correlation between platelet counts (PLT) (OR 1.013, 95% CI: 0.995-1.033; p = 0.164), mean platelet volume (MPV), platelet larger cell ratio (P-LCR), prothrombin time (PT) (OR 1.455, 95% CI 0.979-2.164; p = 0.064), activated partial thromboplastin time (APTT), D-dimer, fibrinogen or antinuclear antibody (ANA) and stroke. Of 17 ITP-IS patients, 7 (53.8%) were cryptogenic, greater than the general IS population. Three (23.1%) of them had an embolic pattern.

CONCLUSION

For ITP patients, age was a significant predictor of stroke. ITP-IS patients had a more cryptogenic origin, with some showing an embolic pattern.

Management of Vascular Thrombosis in Patients with Thrombocytopenia

Platelets play critical roles in hemostasis and thrombosis. While low platelet counts increase the risk of bleeding, antithrombotic drugs, including anticoagulants and antiplatelet agents, are used to treat thromboembolic events. Thus, the management of thrombosis in patients with low platelet counts is challenging with hardly any evidence available to guide treatment. Recognition of the underlying cause of thrombocytopenia is essential for assessing the bleeding risk and tailoring therapeutic options. A typical clinical scenario is the occurrence of venous thromboembolism (VTE) in cancer patients experiencing transient thrombocytopenia during myelosuppressive chemotherapy. In such patients, the severity of thrombocytopenia, thrombus burden, clinical symptoms, and the timing of VTE relative to thrombocytopenia must be considered. In clinical practice, distinct hematological disorders characterized by low platelet counts and a thrombogenic state require specific diagnostics and treatment. These include the antiphospholipid syndrome, heparin-induced thrombocytopenia (HIT) and (spontaneous) HIT syndromes, disseminated intravascular coagulation, and paroxysmal nocturnal hemoglobinuria.

Risk factors of hospitalisation for thrombosis in adults with primary immune thrombocytopenia, including disease-specific treatments: a French nationwide cohort study

We aimed to assess the risk factors of venous thrombosis (VT) and arterial thrombosis (AT) in adults with primary immune thrombocytopenia (ITP), particularly in relation to treatments. The population comprised all incident primary ITP adults in France between 2009 and 2017 (FAITH cohort; NCT03429660) built in the national health database. Outcomes were the first hospitalisation for VT and AT. Multivariable Cox regression models included baseline risk factors, time-varying exposure to ITP drugs, splenectomy and to cardiovascular drugs. The cohort included 10 039 patients. A higher risk of hospitalisation for VT was observed with older age, history of VT, history of cancer, splenectomy [hazard ratio (HR) 3·23, 95% confidence interval (CI) 2·26-4·61], exposure to corticosteroids (HR 3·55, 95% CI 2·74-4·58), thrombopoietin-receptor agonists (TPO-RAs; HR 2·28, 95% CI 1·59-3·26) and intravenous immunoglobulin (IVIg; HR 2·10, 95% CI 1·43-3·06). A higher risk of hospitalisation for AT was observed with older age, male sex, a history of cardiovascular disease, splenectomy (HR 1·50, 95% CI 1·12-2·03), exposure to IVIg (HR 1·85, 95% CI 1·36-2·52) and TPO-RAs (HR 1·64, 95% CI 1·26-2·13). Rituximab was not associated with an increased risk. These findings help to estimate the risk of thrombosis in adult patients with ITP and to select treatment.

Assessment of thrombotic risk during long-term treatment of immune thrombocytopenia with fostamatinib

Background:

Patients with immune thrombocytopenia (ITP) are at risk of bleeding and, paradoxically, thromboembolic events (TEEs), irrespective of thrombocytopenia. The risk of thrombosis is increased by advanced age, obesity, and prothrombotic comorbidities: cancer, hyperlipidemia, diabetes, hypertension, coronary artery disease, and chronic kidney disease, among others. Certain ITP treatments further increase the risk of TEE, especially splenectomy and thrombopoietin receptor agonists. Spleen tyrosine kinase (SYK) is a key signaling molecule common to thromboembolic and hemostatic (in addition to inflammatory) pathways. Fostamatinib is an orally administered SYK inhibitor approved in the USA and Europe for treatment of chronic ITP in adults.

Methods:

The phase III and extension studies included heavily pretreated patients with long-standing ITP, many of whom had risk factors for thrombosis prior to initiating fostamatinib. This report describes long-term safety and efficacy of fostamatinib in 146 patients with up to 5 years of treatment, a total of 229 patient-years, and assesses the incidence of thromboembolic events (by standardized MedDRA query).

Results:

Platelet counts ⩾50,000/µL were achieved in 54% of patients and the safety profile was as described in the phase III clinical studies with no new toxicities observed over the 5 years of follow-up. The only TEE occurred in one patient (0.7%, or 0.44/100 patient-years), who experienced a mild transient ischemic attack. This is a much lower rate than might be expected in ITP patients.

Conclusion:

This report demonstrates durable efficacy and a very low incidence of TEE in patients receiving long-term treatment of ITP with the SYK inhibitor fostamatinib.

ClinicalTrials.gov identifiers:

NCT02076399, NCT02076412, and NCT02077192.

Hemostatic changes by thrombopoietin-receptor agonists in immune thrombocytopenia patients

Thrombopoietin receptor agonist (TPO-RA) treatment increases the thrombosis rate in immune thrombocytopenia (ITP). We hypothesize that TPO-RAs influence platelet function, global and secondary hemostasis and/or fibrinolysis. A systematic review was performed. If possible, data were compared between responders (relevant increase in platelet count), and non-responders. Twelve observational studies with 305 patients were included (responders (127/150 (85%))). There were indications that TPO-RA treatment enhanced platelet function, with respect to platelet-monocyte aggregates, soluble P-selectin, GPVI expression, and adhesion under flow. Studies addressing global and secondary hemostasis and fibrinolysis were scarce. Overall, no changes were found during TPO-RA treatment, apart from an accelerated clot formation and conflicting data on levels of plasminogen activator inhibitor (PAI)-1. The parameters that increased have previously been associated with thrombosis in other patient groups, and might contribute to the increased rate of thrombosis observed in TPO-RA-treated ITP patients.

Ischemic stroke/transient ischemic attack in adults with primary immune thrombocytopenia: a meta-analysis

OBJECTIVE

To carry out a systematic review to help resolve the controversy of ischemic stroke (IS)/transient ischemic attack (TIA) in patients with primary immune thrombocytopenia (ITP).

METHODS

A database search of PubMed and Ovid Embase was conducted for epidemiologic studies published up to December 17, 2019. The effective size was estimated by pooled prevalence, annualized incidence/risk, relative risk (RR), and their corresponding 95% confidence intervals (CIs).

RESULTS

The systematic review included 14 eligible studies from 11 publications. The pooled annualized cumulative incidence was 0.15% (95% CI, 0.03-0.26%) per person-years. And the pooled annualized cumulative risk of IS/TIA of ITP was 0.86% (95% CI, 0.33-1.39%) per year based on 3 population-based cohort studies. There was a higher risk of incident IS/TIA in ITP patients than ITP-free subjects (pooled unadjusted or adjusted RR with 95% CI, 1.46 [1.22-1.74] or 1.50 [1.29-1.73]).

CONCLUSIONS

IS/TIA was not uncommon in patients with primary ITP. ITP patients have a higher risk of IS/TIA compared with the reference cohorts. Healthcare professionals should take into account the risk of IS/TIA when treating ITP patients with or without a history of IS/TIA.

Markers of autoimmunity in immune thrombocytopenia: prevalence and prognostic significance

Prior studies have demonstrated an increased prevalence of autoimmune markers in patients with immune thrombocytopenia (ITP). Clinical experience has suggested that there may be an association between autoimmune markers and poor outcomes in ITP, but current guidelines do not encourage routine testing in these patients. We retrospectively assessed the prevalence of autoimmune markers in adult patients with ITP from our institutional database and used multiple logistic regression analyses to test for an association between autoimmune marker positivity and thrombotic events or clinical remission. We also assessed whether positivity for common autoimmune markers was associated with positivity for platelet autoantibodies. There was a high rate of autoimmune marker positivity in this population, with antinuclear antibody (65%), antithyroid peroxidase antibody (31%), and direct antiglobulin (29%) the most commonly found. Antithyroid peroxidase antibody positivity was associated with a lower probability of remission (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.09-0.79; P = .017). Lupus anticoagulant positivity was associated with a higher rate of thrombosis (OR, 8.92; 95% CI, 1.94-40.95; P = .005), and antinuclear antibody was strongly associated with thrombosis (P = .001). There was no relation between platelet autoantibody positivity and the presence of autoimmune markers. These results suggest that many patients with ITP have a state of immune dysregulation that extends beyond platelet autoantibodies and that certain autoimmune markers may be prognostically useful in this disorder.

New insights into the epidemiology of immune thrombocytopenia in adult patients: Impact for clinical practice

New insights into immune thrombocytopenia (ITP) epidemiology in adult patients highlight three main outcomes of morbidity and mortality: bleeding, infection and thrombosis. This review depicts current evidence about incidence and risk factors of bleeding, infection and thrombosis as well as predictors of chronicity, and shows how this assessment impacts the choice of ITP second-line treatment at the individual-level basis.

Large and small platelets-(When) do they differ?

Platelets are most important in providing cellular hemostasis but also take part in inflammation and immune processes. Increased platelet size has been regarded as a feature describing a young and more reactive subpopulation until studies were published which questioned this concept. Moreover, changes of platelet size given by the mean platelet volume (MPV) were described for immune thrombocytopenia, cardiovascular disease, atherosclerosis, venous thromboembolism, chronic lung disease, sepsis, cancer-associated thrombosis, autoimmune disorders, and others. This review summarizes the literature on what is known about platelets with different size and describes controversies of studies with large and small platelets putting a focus on their thrombogenicity, age, and on the association of MPV with the mentioned diseases.

Use of eltrombopag for patients 65 years old or older with immune thrombocytopenia

BACKGROUND

Eltrombopag is useful for immune thrombocytopenia (ITP). However, results of clinical trials may not accurately mirror clinical practice reality. Here we evaluated eltrombopag for primary and secondary ITP in our ≥65-year-old population.

METHODS

A total of 106 primary ITP patients (16 with newly diagnosed ITP, 16 with persistent ITP, and 74 with chronic ITP) and 39 secondary ITP patients (20 with ITP secondary to immune disorders, 7 with ITP secondary to infectious diseases, and 12 with ITP secondary to lymphoproliferative disorders [LPD]) were retrospectively evaluated.

RESULTS

Median age of our cohort was 76 (interquartile range, IQR, 70-81) years. 75.9% of patients yielded a platelet response including 66.2% complete responders. Median time to platelet response was 14 (IQR, 8-21) days. Median time on response was 320 (IQR, 147-526) days. Sixty-three adverse events (AEs), mainly grade 1-2, occurred. The most common were hepatobiliary laboratory abnormalities (HBLAs) and headaches. One transient ischemic attack in a newly diagnosed ITP and two self-limited pulmonary embolisms in secondary ITP were the only thrombotic events observed.

CONCLUSION

Eltrombopag showed efficacy and safety in ITP patients aged ≥65 years with primary and secondary ITP. However, efficacy results in LPD-ITP were poor. A relatively high number of deaths were observed.

Deciphering predictive factors for choice of thrombopoietin receptor agonist, treatment free responses, and thrombotic events in immune thrombocytopenia

Very few data exist on when a particular thrombopoietin-receptor agonist (TPO-RA) is favored in clinical practice for the treatment of patients with immune thrombocytopenia (ITP), about novel risk factors for vascular events (VE) with these drugs, nor about predictive factors for therapy free responses (TFR). We conducted an observational, retrospective, long-term follow-up multicenter study from November 2016 to January 2018 of 121 adult ITP patients initiating TPO-RA between January 2012 to December 2014. Data reflected that a platelet count ≤25 × 10⁹/l at the time when the TPO-RA was initiated was associated with a 2.8 higher probability of receiving romiplostim vs. eltrombopag (P = 0.010). VE on TPO-RA was related to previous neoplasia in patients over 65 years (50% vs. 2.2%, P < 0.001), and to previous splenectomy in younger patients (100% vs. 33%, P = 0.001). Receiving romiplostim as first TPO-RA with no subsequent TPO-RA switching was associated with a 50% likelihood of TFR after 2.9 years of therapy (3.3 years in chronic ITP patients). These real-world data help deciphering some areas of uncertainty, and offer insight into some of the most relevant challenges of ITP which may help clinicians make appropriate treatment decisions in the management of adult ITP patients with TPO-RA.