Effectiveness and Safety of Romiplostim Among Patients with Newly Diagnosed, Persistent and Chronic Immune Thrombocytopenia in European Clinical Practice

Lymphocyte subpopulations: a potential predictor of a response in patients with immune thrombocytopenia

OBJECTIVES

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder caused by increased platelet destruction and altered production. Despite the well-described pathophysiological background of immune dysregulation, current treatment guidelines consist of monotherapy with different drugs, with no tool to predict which patient is more suitable for each therapeutic modality.

METHODS

In our study, we attempted to determine differences in the immune setting, comparing the patients' responses to administered therapy. During 12-month follow-up, we assessed blood count, antiplatelet autoantibodies, and T lymphocyte subsets in peripheral blood in 35 patients with ITP (newly diagnosed or relapsed disease).

RESULTS

Our data show that the value of antiplatelet autoantibodies, the percentage of cytotoxic T lymphocytes, and the immunoregulatory index (IRI, CD4+ / CD8+ T cell ratio) differ significantly by treatment response. Responders have a higher IRI (median 2.1 vs. 1.5 in non-responders, P = 0.04), higher antiplatelet autoantibodies (median 58 vs. 20% in non-responders, P = 0.01) and lower relative CD8+ T cells count (P = 0.02) before treatment.

DISCUSSION

The results suggest that immunological parameters (antiplatelet autoantibodies, relative CD8+ T cell count and IRI) could be used as prognostic tools for a worse clinical outcome in patients with ITP.

CONCLUSION

These biomarkers could be utilized for stratification and eventually selection of treatment preferring combination therapy.

Severe thrombocytopenia associated to bevacizumab in a patient with scleroderma, gastrointestinal angiodysplasias and refractory gastrointestinal bleeding

This case report discusses the medical history of a 64-year-old woman diagnosed with scleroderma and diffuse gastrointestinal angiodysplasia. The patient received bevacizumab (BVZ) therapy to address gastrointestinal bleeding that was unresponsive to endoscopic treatment. Subsequently, she developed severe thrombocytopenia. Although there were suspicions of an immune-mediated mechanism resulting from BVZ treatment, the laboratory results did not provide conclusive evidence. The patient underwent transfusions, received gamma globulin, and was treated with Romiplostim. Over time, her platelet levels gradually improved, and the bleeding was successfully controlled. It's worth noting that BVZ-induced thrombocytopenia is a relatively rare yet severe adverse effect. Recognizing and understanding the mechanisms behind thrombocytopenia is essential for developing safer treatment approaches. Further research is required to identify potential risk factors associated with this condition.

Can low-dose intravenous immunoglobulin be an alternative to high-dose intravenous immunoglobulin in the treatment of children with newly diagnosed immune thrombocytopenia: a systematic review and meta-analysis

Intravenous immunoglobulin (IVIg) is a first-line treatment for children with newly diagnosed immune thrombocytopenia (ITP). Higher doses of IVIg are associated with a more insupportable financial burden to pediatric patients' families and may produce more adverse reactions. Whether low-dose IVIg (LD-IVIg) can replace high-dose IVIg (HD-IVIg) has yet to be established. We conducted a comprehensive literature search from the establishment of the database to May 1, 2023, and eventually included 22 RCTs and 3 cohort studies compared different dosages of IVIg. A total of 1989 patients were included, with 991 patients in the LD-IVIg group and 998 patients in the HD-IVIg group. Our results showed no significant differences between the two groups in the effective rate (LD-IVIg: 91% vs. HD-IVIg: 93%; RR: 0.99; 95%CI: 0.96-1.02) and the durable remission rate (LD-IVIg: 65% vs. HD-IVIg: 67%; RR: 0.97; 95%CI: 0.89-1.07). Similar results were also found in the time of platelet counts (PC) starting to rise (MD: 0.01, 95%CI: -0.06-0.09), rising to normal (MD: 0.16, 95%CI: -0.03-0.35), and achieving hemostasis (MD: 0.11, 95%CI: -0.02-0.23) between the two groups. Subgroup analysis showed the effective rate of 0.6 g/kg was equal to 1 g/kg subgroup (91%) but higher than 0.8 g/kg subgroup (82%), and a combination with glucocorticoid may contribute to effect enhancement (combined with glucocorticoid: 91% vs. IVIg alone: 86%) whether combined with dexamethasone (92%) or methylprednisolone (91%). Besides, the incidence rate of adverse reactions in the LD-IVIg group (3%) was significantly lower than the HD-IVIg group (6%) (RR: 0.61; 95%CI: 0.38-0.98). So low-dose IVIg (≤ 1 g/kg) is effective, safe, and economical, which can replace high-dose IVIg (2 g/kg) as an initial treatment. This systematic review was registered in PROSPERO (CRD42022384604).

Use of thrombopoietin receptor agonists in adults with immune thrombocytopenia: a systematic review and Central European expert consensus

There are currently three thrombopoietin receptor agonists (TPO-RAs) approved in Europe for treating patients with immune thrombocytopenia (ITP): romiplostim (Nplate®), eltrombopag (Revolade®), and avatrombopag (Doptelet®). However, comparative clinical data between these TPO-RAs are limited. Therefore, the purpose of this study was to perform a literature review and seek expert opinion on the relevance and strength of the evidence concerning the use of TPO-RAs in adults with ITP. A systematic search was conducted in PubMed and Embase within the last 10 years and until June 20, 2022. A total of 478 unique articles were retrieved and reviewed for relevance. The expert consensus panel comprised ITP senior hematologists from eight countries across Central Europe. The modified Delphi method, consisting of two survey rounds, a teleconference and email correspondence, was used to reach consensus. Forty articles met the relevancy criteria and are included as supporting evidence, including five meta-analyses analyzing all three European-licensed TPO-RAs and comprising a total of 31 unique randomized controlled trials (RCTs). Consensus was reached on seven statements for the second-line use of TPO-RAs in the management of adult ITP patients. In addition, the expert panel discussed TPO-RA treatment in chronic ITP patients with mild/moderate COVID-19 and ITP patients in the first-line setting but failed to reach consensus. This work will facilitate informed decision-making for healthcare providers treating adult ITP patients with TPO-RAs. However, further studies are needed on the use of TPO-RAs in the first-line setting and specific patient populations.

Use of Structured Template and Reporting Tool for Real-World Evidence for Critical Appraisal of the Quality of Reporting of Real-World Evidence Studies: A Systematic Review

OBJECTIVES

Real-world evidence (RWE) studies are increasingly being used to support healthcare decisions. Various frameworks, tools, and checklists exist for ensuring quality of real-world data, designing robust studies, and assessing potential for bias. In January 2021, Structured Template and Reporting Tool for RWE (STaRT-RWE) was released to further reduce ambiguity, assumptions, and misinterpretation while planning, implementing, and reporting RWE studies of the safety and effectiveness of treatments. The objective of this study was to identify gaps in the reporting quality of published RWE studies by using this template for critical appraisal.

METHODS

Two reviewers conducted a keyword search on PubMed for free-full-text research articles using real-world data, RWE design, and safety with or without effectiveness outcomes of a medicinal product or intervention in humans of any age or gender, published in English between January 13, 2021, and January 13, 2022. Assessment of risk of bias was done using Assessment of Real-World Observational Studies critical appraisal tool. Deficiencies in methods and findings as per STaRT-RWE template were reported as frequencies.

RESULTS

A total of 54 of 2374 retrieved studies were included in the review. Based on the STaRT-RWE template, the studies inadequately reported empirically defined covariates, power and sample size calculation, attrition, sensitivity analyses, index date (day 0) defining criterion, predefined covariates, outcome, metadata about data source and software, objective, inclusion and exclusion criteria, analysis specifications, and follow-up.

CONCLUSIONS

The use of STaRT-RWE template along with its tables, design diagram, and library of published studies has a potential of improving robustness of RWE studies.

How we treat primary immune thrombocytopenia in adults

Primary immune thrombocytopenia (ITP) is an immune-mediated bleeding disorder characterized by decreased platelet counts and an increased risk of bleeding. Multiple humoral and cellular immune abnormalities result in accelerated platelet destruction and suppressed platelet production in ITP. The diagnosis remains a clinical exclusion of other causes of thrombocytopenia. Treatment is not required except for patients with active bleeding, severe thrombocytopenia, or cases in need of invasive procedures. Corticosteroids, intravenous immunoglobulin, and anti-RhD immunoglobulin are the classical initial treatments for newly diagnosed ITP in adults, but these agents generally cannot induce a long-term response in most patients. Subsequent treatments for patients who fail the initial therapy include thrombopoietic agents, rituximab, fostamatinib, splenectomy, and several older immunosuppressive agents. Other potential therapeutic agents, such as inhibitors of Bruton's tyrosine kinase and neonatal Fc receptor, are currently under clinical evaluation. An optimized treatment strategy should aim at elevating the platelet counts to a safety level with minimal toxicity and improving patient health-related quality of life, and always needs to be tailored to the patients and disease phases. In this review, we address the concepts of adult ITP diagnosis and management and provide a comprehensive overview of current therapeutic strategies under general and specific situations.

Effectiveness and safety of romiplostim among patients with newly diagnosed, persistent and chronic ITP in routine clinical practice in central and Eastern Europe: an analysis of the PLATON study

OBJECTIVES

The objective of this analysis was to assess the effectiveness and safety of romiplostim in the real-world by duration of primary immune thrombocytopenia (ITP): <3 ('newly diagnosed'), 3-12 ('persistent'), and >12 ('chronic') months.

METHODS

This was a post-hoc analysis of the PLATON single-arm, observational cohort study of adults from five Central and Eastern European countries receiving ≥1 romiplostim dose as second-line therapy, or where surgery was contraindicated. Durable (≥75% of measurements with ≥50 × 10⁹ platelets/L during weeks 14-24) and overall platelet response (≥30 or ≥50 × 10⁹ platelets/L at least once), rescue therapy, bleeding, discontinuation of other ITP medications, and adverse drug reactions (ADRs) were assessed.

RESULTS

Of 100 participants, 22.0% had newly diagnosed, 17.0% had persistent, and 61.0% had chronic ITP. Prior splenectomy was most frequently reported in chronic ITP (32.8%), prior bleeding was predominant in newly diagnosed patients (68.2%). Durable platelet response was achieved in 50.0% (95% confidence interval [CI]: 28.2-71.8%) of newly diagnosed, 35.3% (95% CI: 14.2-61.7%) of persistent, and 31.1% (95% CI: 19.9-44.3%) of chronic ITP patients. Overall platelet response was achieved in >80% across all strata. Safety was comparable across groups, with a low incidence of thrombotic ADRs and no bone marrow ADRs.

DISCUSSION

In this real-world study, platelet response to romiplostim was consistent across all strata of ITP duration. ADRs were infrequent and similar across ITP settings.

CONCLUSION

These findings support the utilization of romiplostim in patients with newly diagnosed and persistent ITP in accordance with recent guidelines and the recent romiplostim label extension.