Search Results (39)

Background/Objectives: The field of nephrology is increasingly embracing advanced treatments and clinical trials that focus on inhibiting specific components of the complement cascade, a key driver in complement-mediated kidney diseases. Materials and Methods: This review aims to summarize innovative therapies targeting various pathways, including the inhibition of the terminal part of the complement pathway (mainly C5), the alternative pathway (factor B inhibitors), and the lectin pathway (MASP inhibitors. C5 inhibitors play a critical role in preventing the formation of the membrane attack complex (MAC), offering effective solutions for conditions like atypical hemolytic uremic syndrome (aHUS) and paroxysmal nocturnal hemoglobinuria (PNH). Meanwhile, avacopan, a C5a receptor antagonist, addresses ANCA-associated vasculitis (AAV) by mitigating inflammation and enabling reduced reliance on corticosteroids. Similarly, narsoplimab, which inhibits MASP-2, targets the lectin pathway implicated in conditions such as aHUS. Iptacopan, a factor B inhibitor, focuses on the alternative pathway and demonstrates efficacy in managing C3 glomerulopathy (C3G). Results: A systematic review of complement-targeted therapies was conducted, analysing studies from 2013 to 2023 that address unmet medical needs in primary and secondary glomerular diseases. Conclusions: Our systematic review of complement-targeted therapies shows that these tailored and innovative treatments may specifically address unmet medical needs in primary and secondary glomerular diseases. Full article

Background/Objectives: This analysis was conducted in Italy to estimate the epidemiology of paroxysmal nocturnal hemoglobinuria (PNH) and to describe the features and economic burden of PHN in the adult population considering the role of anti-complement therapy with C5/3-inhibitors (C5/3i). Methods: Administrative databases of healthcare entities covering approximately 12 million citizens were used to estimate the prevalence and incidence of PNH. Demographics, clinical characteristics and healthcare costs were analyzed among adults with PHN stratified by the presence/absence of C5/3i therapy. Results: The prevalence in Dec-2021 of PNH in adults was 17.6/1,000,000 people, and the incidence rate in the period 2011–2022 was 1.5/1,000,000/year. In 142 patients with at least 12 months of data available before and after inclusion (mean age: 50.7 years; 45.8% males), 27% received C5/3i therapy. The main baseline comorbidities were aplastic anemia and other bone marrow failure syndromes, found in 10.6% of patients and more common in C5/3i-treated than untreated patients (18.4% vs. 7.7%). Cost analysis showed that the average cost per patient per year (PPPY) was EUR 41,084, mainly driven by drug expenses (87% of total costs), especially anti-complement therapy (80%). RBC transfusions were the most impactive item among the hospitalization costs (EUR 1982 of EUR 4284 PPPY). The C5/3i-treated cohort was associated with higher total costs (EUR 133,472 vs. EUR 8089, p < 0.001), mainly due to drug expenses (EUR 127,180 vs. EUR 3217, p < 0.001). Conclusions: This real-world analysis confirmed a rising PNH prevalence in Italy, aligning with global data. Despite available therapies, many patients face a high disease burden, suggesting potential benefits from novel treatments targeting upstream complement components. Full article

Thromboembolism (TE) is a major cause of morbidity and mortality in patients with paroxysmal nocturnal hemoglobinuria (PNH). This narrative review summarizes available evidence on TE in Asian patients with PNH and discusses practical considerations and challenges for preventing and managing PNH-associated TE in Asian populations. Evidence suggests that, compared with non-Asians, fewer Asian patients have a history of TE (3.6% vs. 8.9%, p < 0.01), receive anticoagulants (8.5% vs. 16.2%, p = 0.002), or die from TE (6.9% vs. 43.7%, p = 0.000). Independent predictors of TE include lactate dehydrogenase ≥ 1.5 × upper limit of normal, pain, and male sex. Clone size alone does not appear to be a reliable estimate of TE risk. D-dimer levels are a useful marker of hemostatic activation, although they are not specific to PNH. Complement inhibition reduces the incidence of TE, although it does not wholly eliminate TE risk. Eligibility criteria and access to complement inhibitors vary across Asia, with limited availability in some countries. Anticoagulation is required to treat acute TE events and for primary or secondary prophylaxis in selected patients. Physicians and patients must stay alert to the signs and symptoms of TE to ensure prompt and appropriate treatment. Full article

Paroxysmal nocturnal hemoglobinuria (PNH) clones can be identified in a significant proportion of patients with aplastic anemia (AA). Screening for PNH clones at the time of an AA diagnosis is recommended by national and international guidelines. In this report, an expert panel of physicians discusses current best practices and provides recommendations for managing PNH in patients with AA in the Asia–Pacific region. Plasma/serum lactate dehydrogenase (LDH) levels and reticulocyte count should be measured with every blood test. PNH clone size should be monitored regularly by flow cytometry, with on-demand testing in the event of a rise in LDH level ± reticulocyte count or development of symptoms such as thrombosis. Monitoring for PNH clones can guide the choice of initial AA treatment, although flow cytometry has resource implications which may present a challenge in some Asia–Pacific countries. The treatment of patients with both PNH and AA depends on which condition predominates; following PNH treatment guidelines if hemolysis is the main symptom and AA treatment guidelines if bone marrow failure is severe (regardless of whether hemolysis is mild or moderate). The expert panel’s recommendations on the monitoring and treatment of PNH in patients with AA are practical for healthcare systems in the Asia–Pacific region. Full article

Paroxysmal Nocturnal Hemoglobinuria (PNH) constitutes a rare bone marrow failure syndrome characterized by hemolytic anemia, thrombotic events (TEs), and bone marrow aplasia of variable degrees. Thrombosis is one of the major clinical manifestations of the disease, affecting up to 40% of individuals with PNH. Venous thrombosis is more prevalent, affecting mainly unusual sites, such as intrabdominal and hepatic veins. TEs might be the first clinical manifestation of PNH. Complement activation, endothelial dysfunction, hemolysis, impaired bioavailability of nitric oxide, and activation of platelets and neutrophils are implicated in the pathogenesis of TEs in PNH patients. Moreover, a vicious cycle involving the coagulation cascade, complement system, and inflammation cytokines, such as interleukin-6, is established. Complement inhibitors, such as eculizumab and ravulizumab (C5 inhibitors), have revolutionized the care of patients with PNH. C5 inhibitors should be initiated in patients with PNH and thrombosis, while they constitute a great prophylactic measure for TEs in those individuals. Anticoagulants, such as warfarin and low-molecular-weight heparin, and, in selected cases, direct oral anticoagulants (DOACs) should be used in combination with C5 inhibitors in patients who develop TEs. Novel complement inhibitors are considered an alternative treatment option, especially for those who develop extravascular or breakthrough hemolysis when terminal inhibitors are administered. Full article

Flow cytometry plays a fundamental role in the diagnosis of leukemias and lymphomas, as well as in the follow-up and evaluation of minimally measurable disease after treatment. In some instances, such as in the case of acute promyelocytic leukemia (APL), rapid diagnosis is required to avoid death due to serious blood clotting or bleeding complications. Given that promyelocytes do not express the glycophosphatidylinositol (GPI)-anchored protein CD16 and that deficient CD16 expression is a feature of some CD16 polymorphisms and paroxysmal nocturnal hemoglobinuria (PNH), we included the GPI anchor probe FLAER aerolysin in the APL flow cytometry probe panel. Initial tests showed that FLAER binding was absent in pathological promyelocytes from APL patients but was consistently detected with high intensity in healthy promyelocytes from control bone marrow. FLAER binding was studied in 71 hematologic malignancies. Appropriate control cells were obtained from 16 bone marrow samples from patients with idiopathic thrombocytopenic purpura and non-infiltrated non-Hodgkin’s lymphoma. Compared with the positive FLAER signal in promyelocytes from healthy bone marrow, malignant promyelocytes from APL patients showed weak or negative FLAER binding. The FLAER signal in APL promyelocytes was also lower than that in control myeloid progenitors and precursors from patients with other forms of acute myeloid leukemia (AML), B-cell acute lymphoblastic leukemia, or myelodysplastic syndrome. Minimal measurable disease studies performed in APL patients after treatment found normal promyelocyte expression when minimal measurable disease was negative and FLAER-negative promyelocytes when disease relapse was detected. The inclusion of FLAER in the flow cytometry diagnosis and follow-up of APL could be very helpful. Decreased FLAER binding was found in all cases of APL, confirmed by the detection of the PML-RARA fusion transcript and, to a lesser extent, in the other AMLs studied. This study also revealed FLAER differences in other acute leukemias and even between different precursors (myeloid and lymphoid) from healthy controls. However, the reason for FLAER’s non-binding to the malignant precursors of these leukemias remains unknown, and future studies should explore the possible relation with an immune escape phenomenon in these leukemias. Full article

The advent of recycling antibodies, leveraging pH-dependent antigen binding and optimized FcRn interaction, has advanced the field of antibody therapies, enabling extended durability and reduced dosages. Eculizumab (Soliris^®) demonstrated the efficacy of C5 inhibitors for paroxysmal nocturnal hemoglobinuria (PNH), while its derivative, ravulizumab (Ultomiris^®), recognized as a recycling antibody, extended the dosing intervals. However, limitations including intravenous administration and inefficacy in patients with the R885H single-nucleotide polymorphism (SNP) in C5 could necessitate alternative solutions. Crovalimab (PiaSky^®), a next-generation recycling antibody, overcomes these challenges with innovative charge engineering, achieving the enhanced cellular uptake of C5–crovalimab complexes and targeting a unique C5 epitope, allowing for efficacy regardless of the R885H SNP. This study highlights crovalimab’s distinctive molecular features, showing its eliminated binding to Fcγ receptors and C1q, alongside its optimized antigen binding characteristics. The impact of charge engineering was reconfirmed in mice, demonstrating faster C5 clearance than recycling antibodies. Notably, in the maintenance dosing regimen, crovalimab neutralizes approximately seven C5 molecules per antibody on average. Furthermore, its design also reduces the viscosity to facilitate high-concentration formulations suitable for subcutaneous delivery. Consequently, crovalimab offers a four-weekly subcutaneous injection regimen for PNH, marking a substantial improvement in treatment convenience and potentially transforming patients’ quality of life. Full article

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, life-threatening disease characterized by complement-mediated hemolysis. OPERA is the first US longitudinal real-world study on C3 inhibitor therapy, known as pegcetacoplan. Methods: OPERA enrolled US patients with PNH, age ≥18, who were prescribed pegcetacoplan, and data were collected from routine care. Hemoglobin was reported by patients during regular follow-up (censored from transfusions). The Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue (0–52 score) and Patient-Reported Outcomes Measurement Information System scale for Cognitive Function Abilities (PROMIS-CF; 23.27–67.09 t-score) were completed electronically (low score = negative outcome). Patients self-reported incidence of healthcare resource utilization (HCRU). Results: By January 2024, 70 patients (mean age 44.6 years; 57.1% female) reported up to 9 months of pegcetacoplan treatment, with a median [IQR] follow-up of 6.6 [3.8] months. The latest reported hemoglobin levels improved by a mean (SD) of 2.6 (1.9) g/dL from baseline. At 3, 6 and 9 months, patients reported clinically meaningful improvements (≥5 points) in FACIT-F (53.3–69.0%) and (≥2 points) PROMIS-CF (46.7–55.2%). Patients reported a <10% incidence rate per person month of all HCRU events. Conclusions: This first longitudinal real-world US study indicates a positive trend in Hb, fatigue, and cognition with limited HCRU during pegcetacoplan treatment in adults with PNH. Full article

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare and potentially life-threatening hematologic disorder caused by a somatic mutation in a relevant portion of hematopoietic stem cells. Mutation of the phosphatidylinositol glycan biosynthesis class A (PIGA) gene prevents the expression of cell-surface proteins, including the complement regulatory proteins CD55 and CD59. With decreased or a lack of CD55 and CD59 expression on their membranes, PNH red blood cells become susceptible to complement-mediated hemolysis (symptoms of which include anemia, dysphagia, abdominal pain, and fatigue), leading to thrombosis. State-of-the-art PNH treatments act by inhibiting the dysregulated complement at distinct points in the activation pathway: late at the C5 level (C5 inhibitors, eculizumab, ravulizumab, and crovalimab), centrally at the C3 level (C3/C3b inhibitors and pegcetacoplan), and early at the initiation and amplification of the alternative pathway (factor B inhibitor, iptacopan; factor D inhibitor, danicopan). Through their differing mechanisms of action, these treatments elicit varying profiles of disease control and offer valuable insights into the molecular underpinnings of PNH. This narrative review provides an overview of the mechanisms of action of the six complement inhibitors currently approved for PNH, with a focus on the C3/C3b-targeted therapy, pegcetacoplan. Full article

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disease characterized by complement-mediated hemolysis and potentially life-threatening complications. Pegcetacoplan, an inhibitor of complement components C3 and C3b, was approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) in 2021. A recent expansion to its indication by the EMA has made pegcetacoplan available for the treatment of both complement inhibitor-naïve and -experienced patients with PNH who have hemolytic anemia, a similarly broad patient population as in the US. This approval was based on results from the Phase 3 PEGASUS study, where pegcetacoplan showed superiority over the C5 inhibitor eculizumab with regard to improving the hemoglobin level in patients with anemia despite eculizumab treatment, and the Phase 3 PRINCE study, where pegcetacoplan showed superiority over supportive care with regard to hemoglobin stabilization and improving the lactate dehydrogenase level in complement inhibitor-naïve patients. In light of this recent indication expansion by the EMA, this article describes how the strong efficacy of pegcetacoplan is linked to its mechanism of action, which provides broad hemolysis control over both intravascular and extravascular hemolysis to improve a range of disease markers and enhance patients’ quality of life. Furthermore, additional data and learnings obtained from over 3 years of experience with pegcetacoplan are summarized, including long-term efficacy and safety results, real-world clinical experiences, pharmacokinetic characteristics, and extensive practical guidance for the first-to-market proximal complement inhibitor for PNH. Full article

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare, potentially life-threatening haematological disease characterised by chronic complement-mediated haemolysis with multiple clinical consequences that impair quality of life. This post hoc analysis assessed haematological and clinical responses to the first targeted complement C3 inhibitor pegcetacoplan in patients with PNH and impaired bone marrow function in the PEGASUS (NCT03500549) and PRINCE (NCT04085601) studies. For patients with impaired bone marrow function, defined herein as haemoglobin <10 g/dL and absolute neutrophil count <1.5 × 10⁹ cells/L, normalisation of the parameters may be difficult. Indeed, 20% and 43% had normalised haemoglobin in PEGASUS and PRINCE, respectively; 60% and 57% had normalised LDH, and 40% and 29% had normalised fatigue scores. A new set of parameters was applied using changes associated with clinically meaningful improvements, namely an increase in haemoglobin to ≥2 g/dL above baseline, decrease in LDH to ≤1.5× the upper limit of normal, and an increase in fatigue scores to ≥5 points above baseline. With these new parameters, 40% and 71% of PEGASUS and PRINCE patients had improved haemoglobin; 60% and 71% had an improvement in LDH, and 60% and 43% had an improvement in fatigue scores. Thus, even patients with impaired bone marrow function may achieve clinically meaningful improvements with pegcetacoplan. Full article

Platelets play an important role in hemostasis, and a low platelet count usually increases the risk of bleeding. Conditions in which thrombosis occurs despite low platelet counts are referred to as thrombosis with thrombocytopenia syndrome, including heparin-induced thrombocytopenia, vaccine-induced immune thrombotic thrombocytopenia, paroxysmal nocturnal hemoglobinuria, antiphospholipid syndrome, thrombotic microangiopathy (TMA), and disseminated intravascular coagulation. TMA includes thrombotic thrombocytopenic purpura, Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome (HUS), and atypical HUS. Patients with these pathologies present with thrombosis and consumptive thrombocytopenia associated with the activation of platelets and the coagulation system. Treatment varies from disease to disease, and many diseases have direct impacts on mortality and organ prognosis if therapeutic interventions are not promptly implemented. Underlying diseases and the results of physical examinations and general laboratory tests as part of a thorough workup for patients should promptly lead to therapeutic intervention before definitive diagnosis. For some diseases, the diagnosis and initial treatment must proceed in parallel. Utilization of not only laboratory tests but also various scoring systems is important for validating therapeutic interventions based on clinical information. Full article

The co-occurrence of myasthenia gravis (MG) and paroxysmal nocturnal hemoglobinuria (PNH) is rare; only one case has been published so far. We report a 63-year-old Caucasian female patient who was diagnosed with MG at the age of 43. Thymoma was also detected, and so it was surgically resected, which resulted in reasonable disease control for nearly 20 years. Slight hemolysis began to emerge, and then myasthenia symptoms progressed, so immunosuppressive therapy was started. Due to progressive disease and respiratory failure, the patient underwent plasmapheresis, and ventilatory support was stopped. Marked hemolysis was present, and diagnostic tests confirmed PNH with type III PNH cells. Her myasthenia symptoms aggravated, mechanical ventilation had to be started again, and due to the respiratory acidosis, massive hemolysis occurred. After two plasmapheresis sessions, the patient received eculizumab at 600 mg, resulting in prompt hemolysis control. After the second dose of the treatment, the patient was extubated. Still, due to their inability to cough, she developed another respiratory failure and pneumonia–sepsis, resulting in the patient’s death. This case highlights the rare association between these two serious diseases and similar immune-mediated pathophysiology mechanisms involving the complement system. Full article

Background. A common symptom of paroxysmal nocturnal hemoglobinuria (PNH) is fatigue, which in some patients can be severe. Eculizumab (Ecu) has proven efficacy in controlling intravascular hemolysis, but commonly results in persistent anemia and fatigue. Pegcetacoplan’s (Peg) efficacy was documented in the PEGASUS phase III clinical trial, showing improved hemoglobin (Hb) and patient-reported fatigue. This post-hoc analysis sought to describe this fatigue improvement related to Hb normalization using the Functional Assessment of Chronic Illness Therapy—Fatigue subscale (FACIT-F)’s individual questions to speak more directly to patients’ experience and clinicians’ day-to-day practice. Methods. The PEGASUS trial compared Peg with Ecu in patients who remained anemic on Ecu over 16 weeks (n = 41 and 39, for Peg and Ecu, respectively), after which all patients received Peg open label for 32 weeks (“Peg” vs. “Ecu-to-Peg” at Week 48). Hb normalization was defined as ≥12–16 g/dL for females and ≥13.6–18 g/dL for males. The FACIT-F assessed fatigue. Using the complete-case data set, Cohen’s d summarized the effect sizes of the mean FACIT-F item change for both study arms from the baseline to week 16 (n = 36 and 37, for Peg and Ecu, respectively) and from the baseline to week 48 (n = 30 and 29, for Peg and Ecu-to-Peg, respectively), and for Hb-normalized patients in each study arm from the baseline to week 16 (n = 14 and 0, for Peg and Ecu, respectively) and from the baseline to week 48 (n = 10 and 12, for Peg and Ecu-to-Peg, respectively). Results. The FACIT-F scores for both arms were worse at the baseline compared to later in the trial. Peg patients reported improvements on all fatigue items at Week 16, but Ecu patients reported improvement in only one item. At Week 48, the improvement in fatigue was maintained in Peg patients, and Ecu-to-Peg patients’ fatigue improved on all FACIT-F items. Hb normalization was achieved in 14 Peg patients but no Ecu patients at Week 16, and in 10 Peg and 12 Ecu-to-Peg patients, respectively, at week 48. The FACIT-F single items showing the largest change overall, and particularly in Hb-normalized patients across the study arms, were related to symptoms and social limitations. Conclusions. Peg patients reported lasting improvements in fatigue. Patients who were anemic on Ecu reported sustained improvements in fatigue with Peg treatment. Patients who had Hb normalization generally had large, clinically important improvements in fatigue items. Full article

Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal stem cell disease characterized by intravascular hemolysis due to the targeting of affected red blood cells by the complement system. Eculizumab and ravulizumab are two monoclonal antibodies that inhibit the complement system’s components and have been shown to significantly improve survival and quality of life. This review describes the role of these monoclonal antibodies in the treatment of PNH with an emphasis on their safety profile. The challenges in the use of these drugs and new drugs in various stages of drug development are also described, which may be helpful in addressing some of these challenges. Full article