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International Journal of Hematology Nov 2023Thrombotic thrombocytopenic purpura (TTP) can rapidly become a life-threatening condition, and the importance of its appropriate diagnosis and treatment cannot be...
Thrombotic thrombocytopenic purpura (TTP) can rapidly become a life-threatening condition, and the importance of its appropriate diagnosis and treatment cannot be overstated. Until recently, TTP has mainly been diagnosed by clinical findings such as thrombocytopenia and hemolytic anemia. In addition to these clinical findings, however, reduced activity of a disintegrin-like and metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13) below 10% has become internationally accepted as a diagnostic criterion for TTP. TTP is classified as immune-mediated TTP (iTTP) if the patient is positive for anti-ADAMTS13 autoantibodies, and as congenital TTP (cTTP) if ADAMTS13 gene abnormalities are detected. Fresh frozen plasma (FFP) transfusion is performed in patients with cTTP to supplement ADAMTS13. Plasma exchange therapy using FFP is conducted in patients with iTTP to supplement ADAMTS13 and to remove both anti-ADAMTS13 autoantibodies and unusually large von Willebrand factor (VWF) multimers. To suppress autoantibody production, corticosteroid therapy is administered in conjunction with plasma exchange. The monoclonal anti-CD-20 antibody rituximab is effective in patients with iTTP. In addition, caplacizumab, an anti-VWF A1 domain nanobody, has a novel mechanism of action, involving direct inhibition of platelet glycoprotein Ib-VWF binding. The recommended first-line treatments of iTTP in Japan are plasma exchange and corticosteroids, as well as caplacizumab.
Topics: Humans; Purpura, Thrombotic Thrombocytopenic; Japan; von Willebrand Factor; Plasma Exchange; Autoantibodies; ADAMTS13 Protein
PubMed: 37689812
DOI: 10.1007/s12185-023-03657-0 -
Lancet (London, England) Nov 2023Primary immune thrombocytopenia is an autoimmune disorder mediated partly by platelet autoantibodies, resulting in thrombocytopenia, bleeding, and constitutional... (Randomized Controlled Trial)
Randomized Controlled Trial
Efficacy and safety of the neonatal Fc receptor inhibitor efgartigimod in adults with primary immune thrombocytopenia (ADVANCE IV): a multicentre, randomised, placebo-controlled, phase 3 trial.
BACKGROUND
Primary immune thrombocytopenia is an autoimmune disorder mediated partly by platelet autoantibodies, resulting in thrombocytopenia, bleeding, and constitutional symptoms. Efgartigimod, a first-in-class novel human IgG1 Fc fragment, binds the neonatal Fc receptor with high affinity and thus reduces serum IgG concentrations, including autoantibodies. The objective of this study was to evaluate the efficacy and safety of efgartigimod in adults with persistent and chronic primary immune thrombocytopenia.
METHODS
This phase 3, multicentre, randomised, double-blinded, placebo-controlled, 24-week study evaluated the efficacy and safety of intravenous efgartigimod in adults aged 18 years or older with chronic or persistent primary immune thrombocytopenia who had an average platelet count of less than 30 000, had responded to at least one previous immune thrombocytopenia therapy, and were on a concurrent therapy at baseline or had received at least a second previous immune thrombocytopenia therapy. The study took place in 71 participating sites from Asia, Europe, and North America. Patients were randomly assigned 2:1 to receive either efgartigimod (10 mg/kg) or placebo intravenously for the first 4 weeks, after which the dosing schedule could be altered to once per week or every other week depending on the patients' platelet count. The primary endpoint, evaluated in the chronic population, was sustained platelet count response (≥50 × 10 for at least 4 of the last 6 weeks). This study is registered with ClinicalTrials.gov (NCT04188379) and is completed.
FINDINGS
A total of 205 patients were screened from Dec 9, 2019, to Feb 3, 2022, and 131 (86 in the efgartigimod group; 45 in the placebo group) were randomly assigned. These patients represented a population with long-term disease who had a mean time since diagnosis of 10·6 years and 67% (88/131) of whom had received at least three previous immune thrombocytopenia treatments. 22% (17/78) of patients with chronic immune thrombocytopenia receiving efgartigimod reached the primary endpoint compared with 5% (2/40) of those receiving placebo (p=0·032; adjusted difference in response, 16% [95% CI 2·6-26·4]). The median number of weeks of disease control in patients with chronic immune thrombocytopenia was 2·0 (IQR 0·0-11·0) for efgartigimod versus 0·0 (0·0-1·0) for placebo (p=0·0009). Efgartigimod was well tolerated; most adverse events were mild to moderate in severity. The most common adverse events of interest in both groups were headache (16% in efgartigimod and 13% in placebo), haematuria (16% in efgartigimod and 16% in placebo), and petechiae (15% in efgartigimod and 27% in placebo).
INTERPRETATION
Efgartigimod significantly increased sustained platelet count responses compared with placebo in patients with chronic immune thrombocytopenia, including those who had received multiple previous immune thrombocytopenia therapies. Upon completion of the ADVANCE IV study, patients could enroll in the ongoing open-label extension. Subcutaneous efgartigimod is currently being evaluated in patients with immune thrombocytopenia in the ADVANCE SC+ trial.
FUNDING
argenx.
Topics: Adult; Humans; Autoantibodies; Double-Blind Method; Platelet Count; Purpura, Thrombocytopenic, Idiopathic; Receptors, Fc; Thrombocytopenia; Treatment Outcome
PubMed: 37778358
DOI: 10.1016/S0140-6736(23)01460-5 -
La Revue Du Praticien Dec 2023ADULT IGA VASCULITIS. IgA vasculitis previously named rheumatoid purpura is a rare systemic vasculitis in adults involving small vessels and associated with the presence...
ADULT IGA VASCULITIS. IgA vasculitis previously named rheumatoid purpura is a rare systemic vasculitis in adults involving small vessels and associated with the presence of immunoglobulin A deposits. IgA vasculitis is often triggerd by infections, taking medication and vaccination. It is characterised by the presence of vascular purpura associated with joint (arthralgia), gastrointestinal (abdominal pain) and sometimes renal involvement (glomerulonephritis). Gastrointestinal involvement can be lifethreatening (bowel perforation), while the longterm prognosis is shaped by the renal involvement (renal failure). In most cases, the disease has a good outcome and only symptomatic treatment is recommended. In more severe forms, corticosteroids, combined with another immunosuppressant or biotherapy, may be discussed on a casebycase basis.
Topics: Adult; Humans; IgA Vasculitis; Abdominal Pain; Glomerulonephritis; Immunosuppressive Agents; Renal Insufficiency
PubMed: 38294484
DOI: No ID Found -
British Journal of Haematology Oct 2023A subset of individuals with 'primary' or 'idiopathic' immune thrombocytopenia (ITP) who fail to respond to conventional first- and second-line agents or who lose... (Review)
Review
A subset of individuals with 'primary' or 'idiopathic' immune thrombocytopenia (ITP) who fail to respond to conventional first- and second-line agents or who lose responsiveness are considered to have 'refractory' disease (rITP), placing them at increased risk of bleeding and complications of intensive treatment. However, the criteria used to define the refractory state vary among studies, which complicates research and clinical investigation. Moreover, it is unclear whether rITP is simply 'more severe' ITP, or if there are specific pathogenic pathways that are more likely to result in refractory disease, and whether the presence or development of rITP can be established or anticipated based on these differences. This paper reviews potential biological features that may be associated with rITP, including genetic and epigenetic risk factors, dysregulation of T cells and cytokine networks, antibody affinity and specificity, activation of complement, impaired platelet production and alterations in platelet viability and clearance. These findings indicate the need for longitudinal studies using novel clinically available methodologies to identify and monitor pathogenic T cells, platelet antibodies and other clues to the development of refractory disease.
Topics: Humans; Purpura, Thrombocytopenic, Idiopathic; Antibodies; Antibody Affinity; Blood Platelets; Cytokines; Thrombocytopenia
PubMed: 37735546
DOI: 10.1111/bjh.19083 -
Platelets Dec 2023Spleen tyrosine kinase (SYK) is an important regulatory molecule of signal transduction pathways involved in the pathogenesis of autoimmune diseases such as immune... (Review)
Review
Spleen tyrosine kinase (SYK) is an important regulatory molecule of signal transduction pathways involved in the pathogenesis of autoimmune diseases such as immune thrombocytopenia (ITP), and the SYK-signaling pathway has emerged as a potential target for the treatment of numerous diseases. The aim of this narrative review is to summarize the biological properties of SYK and its involvement in disease pathways, provide an update on SYK inhibitors in the treatment of ITP, and consider other potential applications. Fostamatinib, the only licensed SYK inhibitor to date, produces clinical response in ITP patients, including those who are refractory to other treatments. It appears to reduce the risk of thrombotic events and may therefore be a drug to consider for patients with an increased thrombotic risk. Encouraging results have also been obtained in the treatment of warm autoimmune hemolytic anemia. Several other SYK inhibitors have entered clinical trials for a range of indications, reflecting the ability of these drugs to affect multiple signaling pathways. SYK inhibitors have the potential to target several aspects of COVID-19 pathogenesis including thrombosis, without affecting normal hemostasis, and data from the first study of fostamatinib in COVID-19 are encouraging. It is hoped that ongoing trials in autoimmune indications other than ITP, as well as in hematological malignancies and other disorders, confirm the promise of SYK inhibitors.
Topics: Humans; Aminopyridines; COVID-19; Oxazines; Protein Kinase Inhibitors; Purpura, Thrombocytopenic, Idiopathic; Pyridines; Syk Kinase
PubMed: 36331249
DOI: 10.1080/09537104.2022.2131751 -
Frontiers in Immunology 2023The pathophysiology of immune thrombocytopenia (ITP) is complex and encompasses innate and adaptive immune responses, as well as megakaryocyte dysfunction. Rituximab is... (Review)
Review
The pathophysiology of immune thrombocytopenia (ITP) is complex and encompasses innate and adaptive immune responses, as well as megakaryocyte dysfunction. Rituximab is administered in relapsed cases and has the added benefit of inducing treatment-free remission in over 50% of patients. Nevertheless, the responses to this therapy are not long-lasting, and resistance development is frequent. B cells, T cells, and plasma cells play a role in developing resistance. To overcome this resistance, targeting these pathways through splenectomy and novel therapies that target FcγR pathway, FcRn, complement, B cells, plasma cells, and T cells can be useful. This review will summarize the pathogenetic mechanisms implicated in rituximab resistance and examine the potential therapeutic interventions to overcome it. This review will explore the efficacy of established therapies, as well as novel therapeutic approaches and agents currently in development.
Topics: Humans; Rituximab; Purpura, Thrombocytopenic, Idiopathic; Thrombocytopenia; B-Lymphocytes; Remission Induction
PubMed: 37575230
DOI: 10.3389/fimmu.2023.1215216 -
International Journal of Molecular... Feb 2024The management of immune thrombocytopenia (ITP) and the prediction of patient response to therapy still represent a significant and constant challenge in hematology. ITP... (Review)
Review
The management of immune thrombocytopenia (ITP) and the prediction of patient response to therapy still represent a significant and constant challenge in hematology. ITP is a heterogeneous disease with an unpredictable evolution. Although the pathogenesis of ITP is currently better known and its etiology has been extensively studied, up to 75% of adult patients with ITP may develop chronicity, which represents a significant burden on patients' quality of life. A major risk of ITP is bleeding, but knowledge on the exact relationship between the degree of thrombocytopenia and bleeding symptoms, especially at a lower platelet count, is lacking. The actual management of ITP is based on immune suppression (corticosteroids and intravenous immunoglobulins), or the use of thrombopoietin receptor agonists (TPO-RAs), rituximab, or spleen tyrosine kinase (Syk) inhibitors. A better understanding of the underlying pathology has facilitated the development of a number of new targeted therapies (Bruton's tyrosine kinase inhibitors, neonatal Fc receptors, strategies targeting B and plasma cells, strategies targeting T cells, complement inhibitors, and newer TPO-RAs for improving megakaryopoiesis), which seem to be highly effective and well tolerated and result in a significant improvement in patients' quality of life. The disadvantage is that there is a lack of knowledge of the predictive factors of response to treatments, which would help in the development of an optimized treatment algorithm for selected patients.
Topics: Adult; Infant, Newborn; Humans; Purpura, Thrombocytopenic, Idiopathic; Quality of Life; Thrombocytopenia; Platelet Count; Immunoglobulins, Intravenous; Thrombopoietin; Recombinant Fusion Proteins
PubMed: 38396839
DOI: 10.3390/ijms25042163 -
Blood Jan 2024Thrombocytopenia in older individuals is a common but diagnostically challenging condition that has variable clinical impact to those who are affected. Diagnostic...
Thrombocytopenia in older individuals is a common but diagnostically challenging condition that has variable clinical impact to those who are affected. Diagnostic approach requires evaluation of the preexisting clinical conditions, detailed review of medications, and assessment for disorders that warrant urgent treatment. In this article, we describe a systematic approach to diagnosis of thrombocytopenia and present a schematic review for management strategies. Three clinical scenarios are presented that are relevant for their prevalence and management challenges in an older adult population. The first scenario addresses primary immune thrombocytopenia (ITP) and reviews different treatment options. The second one addresses complications of thrombocytopenia in management of the myelodysplastic syndrome. The last one reviews diagnostic challenges of drug-induced ITP.
Topics: Humans; Aged; Thrombocytopenia; Myelodysplastic Syndromes; Purpura, Thrombocytopenic, Idiopathic
PubMed: 37956435
DOI: 10.1182/blood.2022017634 -
Genes Oct 2023Hereditary thrombotic thrombocytopenic purpura (hTTP), also known as Upshaw-Schulman syndrome, is a rare genetic disorder caused by mutations in the ADAMTS13 gene that... (Review)
Review
Hereditary thrombotic thrombocytopenic purpura (hTTP), also known as Upshaw-Schulman syndrome, is a rare genetic disorder caused by mutations in the ADAMTS13 gene that leads to decreased or absent production of the plasma von Willebrand factor (VWF)-cleaving metalloprotease ADAMTS13. The result is circulating ultra-large multimers of VWF that can cause microthrombi, intravascular occlusion and organ damage, especially at times of turbulent circulation. Patients with hTTP may have many overt or clinically silent manifestations, and a high index of suspicion is required for diagnosis. For the treatment of hTTP, the goal is simply replacement of ADAMTS13. The primary treatment is prophylaxis with plasma infusions or plasma-derived factor VIII products, providing sufficient ADAMTS13 to prevent acute episodes. When acute episodes occur, prophylaxis is intensified. Recombinant ADAMTS13, which is near to approval, will immediately be the most effective and also the most convenient treatment. In this review, we discuss the possible clinical manifestations of this rare disease and the relevant differential diagnoses in different age groups. An extensive discussion on prophylaxis and treatment strategies is also presented. Unique real patient cases have been added to highlight critical aspects of hTTP manifestations, diagnosis and treatment.
Topics: Humans; Purpura, Thrombotic Thrombocytopenic; von Willebrand Factor; ADAM Proteins; Mutation; Diagnosis, Differential
PubMed: 37895305
DOI: 10.3390/genes14101956 -
QJM : Monthly Journal of the... Jul 2023
Topics: Humans; IgA Vasculitis; Vasculitis; Vasculitis, Leukocytoclastic, Cutaneous
PubMed: 36912689
DOI: 10.1093/qjmed/hcad038