RESUMEN

Paroxysmal nocturnal hemoglobinuria is a rare clonal hematopoietic stem cell disorder with debilitating health consequences if untreated. Although cases have been described globally, precise epidemiological distribution is difficult to assess due to geographical underrepresentation in disease reporting. Evaluation of the burden of paroxysmal nocturnal hemoglobinuria in Bulgaria is currently missing. To provide epidemiological estimates, a systematic literature search for publications in the Bulgarian language or by Bulgarian authors was performed for a ten-year period (2013-2022), and clinically relevant information on case presentation was collected. Additionally, data was retrieved from the National Health Insurance Fund and National Statistical Institute on the count of registered cases with ICD-10 code "D59.5" and census for the same period. The estimated prevalence of paroxysmal nocturnal hemoglobinuria is relatively lower in the Bulgarian population than in other countries, and it is estimated to be 2.77 cases per 1,000,000 patient years. The treatment pattern mainly shows conventional blood product support use and is consistent with the pre-complement inhibition era. Underdiagnosis, lack of a reliable disease reporting system, and, until recently, restricted access to complement inhibitor therapy are significant impediments to the management of paroxysmal nocturnal hemoglobinuria in Bulgaria.

RESUMEN

OBJECTIVES: To describe real-world use/effectiveness of pegcetacoplan (PEG) in paroxysmal nocturnal haemoglobinuria (PNH). METHODS: Data were drawn from the Adelphi PNH Disease Specific Programme™, a cross-sectional survey conducted in France, Italy, Germany, Spain and the United States from January to November 2022. Patients had a confirmed PNH diagnosis and received PEG for ≥1 month. Physicians reported patient characteristics, treatment use/satisfaction and their perception of patients' fatigue and health-related quality of life (HRQoL). Patients reported treatment satisfaction and completed questionnaires assessing fatigue, HRQoL and productivity. Descriptive statistics were reported. RESULTS: Overall, 14 physicians provided data for 61 patients who had received 1080 mg/dose PEG for 1.3-14.8 months. At data collection compared to PEG initiation: haemoglobin was 2.5 g/dL higher on average; proportion of patients with lactate dehydrogenase (LDH) ≥1.5 × upper limit of normal was reduced by 27.4%; physician-perceived fatigue was lower and HRQoL better. Physician- and patient-reported treatment satisfaction was high for >90% of patients. Physicians and patients were more satisfied with PEG than previously prescribed C5 complement inhibitors. Mean work impairment and activity impairment in the 7 days prior to data collection were 32.9% and 22.4%, respectively. CONCLUSIONS: These real-world data support the effectiveness of PEG through positive effects on haemoglobin, LDH, fatigue and HRQoL.

Asunto(s)

Hemoglobinuria Paroxística , Péptidos Cíclicos , Calidad de Vida , Humanos , Estados Unidos , Hemoglobinuria Paroxística/diagnóstico , Hemoglobinuria Paroxística/tratamiento farmacológico , Estudios Transversales , Resultado del Tratamiento , L-Lactato Deshidrogenasa , Hemoglobinas

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Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide, characterized by the deposition of IgA in the mesangial area of the glomerulus. At present, the pathogenesis of IgAN is not yet clear, and there has been a lack of specific and recognized treatment plans. In recent years, many domestic and foreign researchers have conducted research on important pathways and key molecules in its pathogenesis, aiming to explore new therapeutic drugs. This review mainly summarizes the latest progress in the treatment of IgAN, including drugs that have been proven effective against IgAN and drugs that are currently being evaluated in clinical studies.

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Two central questions in COVID-19 treatment which should be considered are: "How does the imbalance of the complement system affect the therapeutic approaches?" and "Do we consider complement inhibitors in therapeutic protocols?". The complement system is a double-edged sword since it may either promote immune responses against COVID-19 or contribute to destructive inflammation in the host. Therefore, it is crucial to regulate this system with complement inhibitors. In this manuscript, we discuss the molecular mechanisms of complement and complement inhibitors in COVID-19 patients. We searched the terms "COVID-19", "Complement", "Complement inhibitor", "SARS-CoV-2", and all complement fragments and inhibitors from 2000 to 2022 in PubMed and google scholar and checked the pathways in "KEGG pathway database". Complement is not well-appreciated in the treatment protocols despite its multiple roles in the disease, and most of the preventive anti-inflammatory therapeutic approaches did not include a complement inhibitor in COVID-19 therapeutic protocols. In this review article, we discussed the most recent studies regarding complement components mediated interventions and the mechanism of these interventions in COVID-19 patients. Since the control of the complement system overactivation is associated with a better prognosis in the initial stages of COVID-19, heparin, anti-thrombin, C1-inhibitor, montelukast, and hydralazine can be effective in the initial stages of this viral infection. Recombinant complement activation (RCA) proteins are more effective in regulating complement compared to terminal pathway therapeutic approaches such as the C3a and C5a inhibitors.

Asunto(s)

COVID-19 , Humanos , Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Activación de Complemento , Inactivadores del Complemento/uso terapéutico , Inactivadores del Complemento/farmacología , Factores Inmunológicos

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INTRODUCTION: Hemolysis in paroxysmal nocturnal hemoglobinuria (PNH) is complement-mediated due to the lack of complement inhibitors in the hemopoietic cell membranes, making complement inhibition the best approach to manage PNH. Three complement inhibitors are approved by the European Medicines Agency as targeted therapy for PNH: eculizumab and ravulizumab, two humanized monoclonal antibodies targeting the same complement 5 (C5) epitope, approved in 2007 and 2019, respectively, and the more recently approved cyclic peptide, the complement 3 (C3) inhibitor pegcetacoplan. Although national and international PNH treatment guidelines exist, they do not take into consideration the latest clinical trial evidence. Given the lack of evidence-based data for some clinical situations encountered in real life, we identified specific populations of patients who may benefit from switching to proximal C3 from terminal C5 inhibition. METHODS: The expert recommendations presented here were created using a Delphi-like process by a group of expert PNH specialists across Central Europe. Based on an initial advisory board meeting discussion, recommendations were prepared and reviewed as part of a Delphi survey to test agreement. RESULTS: Using a systematic approach, literature databases were searched for relevant studies, and 50 articles were reviewed by the experts and included as supporting evidence. CONCLUSION: Implementation of these recommendations uniformly across healthcare institutions will promote the best use of complement inhibition in managing PNH, and has the potential to positively impact patient outcomes in Central Europe and worldwide.

Asunto(s)

Hemoglobinuria Paroxística , Humanos , Hemoglobinuria Paroxística/tratamiento farmacológico , Testimonio de Experto , Inactivadores del Complemento/uso terapéutico , Inactivadores del Complemento/metabolismo , Complemento C3/metabolismo , Complemento C3/uso terapéutico , Complemento C5/uso terapéutico , Europa (Continente)

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Therapy of myasthenia gravis (MG) is increasingly oriented to the patient's antibody status. In addition to symptomatic therapy, steroids, classic long-term immunosuppressive therapies and thymectomy are regularly used. In recent years, new therapeutic approaches have been developed that particularly benefit acetylcholine receptor (AChR) antibody (Abs) positive patients with highly active disease. While the C5 complement inhibitor eculizumab was reserved for treatment-refractory generalized courses of AChR-Abs positive MG, two new drugs, the neonatal Fc receptor inhibitor efgartigimod and the more advanced C5 complement inhibitor ravulizumab, have recently been approved as add-on therapy for AChR-Abs positive generalized MG (gMG). In highly active courses of MG with Abs against the muscle-specific receptor tyrosine kinase (MuSK), the use of rituximab should be considered early in the course of the disease. The efficacy of the new drugs in children and adolescents with juvenile MG (JMG) is currently being tested in clinical trials. The new guideline recommends the use of modern immunomodulators based on a step-by-step approach depending on disease activity. With the German Myasthenia Register (MyaReg), the changing therapeutic landscape and quality of life of patients with myasthenic syndromes can be assessed, thus providing real-world data on the care of MG patients. Despite treatment based on the previous guideline, many MG patients suffer considerable impairment to their quality of life. With the new immunomodulators, there is the possibility of early intensified immunotherapy, which, in contrast to long-term immunosuppressants, can lead to a rapid improvement in the course of the disease.

Asunto(s)

Miastenia Gravis , Calidad de Vida , Recién Nacido , Humanos , Niño , Adulto , Adolescente , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamiento farmacológico , Receptores Colinérgicos , Autoanticuerpos , Factores Inmunológicos/uso terapéutico , Inactivadores del Complemento/uso terapéutico

RESUMEN

Membranoproliferative glomerulonephritis (MPGN) is a pattern of glomerular injury that may be primary or secondary to infections, autoimmune diseases and haematological disorders. Primary C3G and IC-MPGN are rare and the prognosis is unfavourable. Based on immunofluorescence findings, MPGN has been classified into complement-mediated C3 glomerulopathy (C3G) and immune complex-mediated MPGN (IC-MPGN). However, this classification leaves a number of issues unresolved. The finding of genetic and acquired complement abnormalities in both C3G and IC-MPGN indicates that they represent a heterogeneous spectrum rather than distinct diseases. An unsupervised hierarchical clustering in a cohort of patients with primary C3G and IC-MPGN identified four distinct pathogenetic patterns, characterized by specific histologic and clinical features, and genetic and acquired complement abnormalities. These results provide the groundwork for a more accurate diagnosis and the development of targeted therapies. The drugs that are currently used, such as corticosteroids and immunosuppressants, are frequently ineffective in primary C3G and IC-MPGN. Eculizumab, an anti-C5 monoclonal antibody, has been used occasionally in single cases or small series. However, only a few patients have achieved remission. This heterogeneous response could be related to the extent of terminal complement activation, which may vary substantially from patient to patient. Several drugs that target the complement system at different levels are under investigation for C3G and IC-MPGN. However, clinical trials to test new therapeutics will be challenging and heavily influenced by the heterogeneity of these diseases. This creates the need to characterize each patient to match the specific complement abnormality with the type of intervention.

Asunto(s)

Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Enfermedades Renales , Humanos , Glomerulonefritis Membranoproliferativa/diagnóstico , Glomerulonefritis Membranoproliferativa/etiología , Glomerulonefritis Membranoproliferativa/terapia , Glomérulos Renales/patología , Activación de Complemento

RESUMEN

Dysregulation and accelerated activation of the alternative pathway (AP) of complement is known to cause or accentuate several pathologic conditions in which kidney injury leads to the appearance of hematuria and proteinuria and ultimately to the development of chronic renal failure. Multiple genetic and acquired defects involving plasma- and membrane-associated proteins are probably necessary to impair the protection of host tissues and to confer a significant predisposition to AP-mediated kidney diseases. This review aims to explore how our current understanding will make it possible to identify the mechanisms that underlie AP-mediated kidney diseases and to discuss the available clinical evidence that supports complement-directed therapies. Although the value of limiting uncontrolled complement activation has long been recognized, incorporating complement-targeted treatments into clinical use has proved challenging. Availability of anti-complement therapy has dramatically transformed the outcome of atypical hemolytic uremic syndrome, one of the most severe kidney diseases. Innovative drugs that directly counteract AP dysregulation have also opened new perspectives for the management of other kidney diseases in which complement activation is involved. However, gained experience indicates that the choice of drug should be tailored to each patient's characteristics, including clinical, histologic, genetic, and biochemical parameters. Successfully treating patients requires further research in the field and close collaboration between clinicians and researchers who have special expertise in the complement system.

Asunto(s)

Síndrome Hemolítico Urémico Atípico , Enfermedades Renales , Humanos , Riñón/patología , Enfermedades Renales/terapia , Enfermedades Renales/patología , Proteínas del Sistema Complemento , Síndrome Hemolítico Urémico Atípico/tratamiento farmacológico , Síndrome Hemolítico Urémico Atípico/patología , Activación de Complemento

RESUMEN

The complement system is critical to human health owing to its central role in host defense and innate immunity. During pregnancy, the complement system must be appropriately regulated to allow for immunologic tolerance to the developing fetus and placenta. Although some degree of complement activation can be seen in normal pregnancy, the fetus seems to be protected in part through the placental expression of complement regulatory proteins, which inhibit complement activation at different steps along the complement activation cascade. In women who develop preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome, there is a shift toward increased complement activation and decreased complement regulation. There is an increase in placental deposition of C5b-9, which is the terminal effector of classical, lectin, and alternative complement pathways. C5b-9 deposition stimulates trophoblasts to secrete soluble fms-like tyrosine kinase-1, which sequesters vascular endothelial growth factor and placental growth factor. Pathogenic mutations or deletions in complement regulatory genes, which predispose to increased complement activation, have been detected in women with preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome. Before the disease, biomarkers of alternative complement pathway activation are increased; during active disease, biomarkers of terminal complement pathway activation are increased. Urinary excretion of C5b-9 is associated with preeclampsia with severe features and distinguishes it from other hypertensive disorders of pregnancy. Taken together, existing data link preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome with increased activation of the terminal complement pathway that, in some cases, may be influenced by genetic alterations in complement regulators. These findings suggest that the inhibition of the terminal complement pathway, possibly through C5 blockade, may be an effective strategy to treat preeclampsia and hemolysis, elevated liver enzymes, and low platelet count syndrome, but this strategy warrants further evaluation in clinical trials.

Asunto(s)

Activación de Complemento , Síndrome HELLP/inmunología , Preeclampsia/inmunología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Biomarcadores/sangre , Inactivadores del Complemento/uso terapéutico , Proteínas del Sistema Complemento/análisis , Proteínas del Sistema Complemento/genética , Femenino , Síndrome HELLP/sangre , Síndrome HELLP/tratamiento farmacológico , Humanos , Mutación , Factor de Crecimiento Placentario/sangre , Preeclampsia/sangre , Preeclampsia/tratamiento farmacológico , Embarazo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre

RESUMEN

Eculizumab (ECU), a C5 complement inhibitor, is approved to treat acetylcholine receptor autoantibody positive generalized myasthenia gravis (AChR MG). The clinical effect of ECU relies on inhibition of the terminal complement complex; however, the effect of ECU on lymphocytes is largely unknown. We evaluated innate and adaptive immunity among AChR MG patients (N = 3) before ECU and ≥3 months later while on stable therapy, and found reduced activation markers in memory CD4+ T cell subsets, increased regulatory T cell populations, and reduced frequencies of CXCR5+HLA-DR+CCR7+ Tfh subsets and CD11b+ migratory memory B cells. We observed increases within CD8+ T cell subsets that were terminally differentiated and senescent. Our data suggest complement inhibition with ECU modulates the adaptive immunity in patients with MG, consistent with preclinical data showing changes in complement-mediated signaling by T- and antigen-presenting cells. These findings extend our understanding of ECU's mechanism of action when treating patients with MG.

Asunto(s)

Anticuerpos Monoclonales Humanizados/uso terapéutico , Linfocitos B/efectos de los fármacos , Inactivadores del Complemento/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Linfocitos T/efectos de los fármacos , Inmunidad Adaptativa/efectos de los fármacos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/inmunología

RESUMEN

Objective: To report the case of a 35-year-old woman with treatment-resistant aquaporin-4 (AQP-4) immunoglobulin G (IgG) seronegative neuromyelitis optica spectrum disorder (NMOSD) successfully treated with eculizumab (a terminal complement inhibitor). Methods: The investigational procedures and treatment regimens the patient received were documented over 8 years [2012 (first presentation) to 2020]. Results: The patient presented with subacute onset of lower-limb weakness and numbness, gait imbalance, and urinary incontinence. Magnetic resonance imaging (MRI) showed abnormalities in the thoracic spine from T7 to T10, but brain and cervical spine scans, visual evoked potential latencies, and IgG index were normal; cerebrospinal fluid pleocytosis and oligoclonal bands were both present. After treatment with intravenous methylprednisolone 1 g/day for 5 days, the patient was discharged without medication to acute rehabilitation but experienced relapses from 2012 to 2014. She was treated with oral prednisone (initiated at 40 mg/day in 2014; the dose was halved in 2015 due to weight gain) and mycophenolate mofetil (MMF) 1 g twice daily (from June 2015), but between 2014 and 2019 experienced 4-5 relapses/year, requiring treatment with intravenous methylprednisolone, with added maintenance plasma exchange from 2018 onwards. Although the patient tested negative for antibodies to AQP-4 and myelin oligodendrocyte glycoprotein, she was diagnosed with NMOSD in February 2017, based on recurrent episodes of longitudinal extensive transverse myelitis, MRI changes, and area postrema syndrome. By 2018 the patient needed a cane to walk. Prednisone and MMF were discontinued mid-2018, and rituximab was prescribed from July 2018 (maintenance regimen two 1 g doses 2 weeks apart every 6 months) but discontinued in July 2019 owing to lack of significant improvement. From July 2019 eculizumab was prescribed for 6 months (900 mg weekly for the first four doses, then 1200 mg every 2 weeks). The patient had no relapses or adverse events during and after eculizumab treatment (as of August 2020) and was able to walk unaided; her Expanded Disability Status Scale score improved from 4-5 during 2015-2018 to 2 in 2020 following eculizumab treatment. Conclusion: Eculizumab shows promise as a treatment for AQP-4 IgG-seronegative NMOSD and further studies are warranted.

RESUMEN

INTRODUCTION: Terminal complement amplification is hypothesized to be a key contributor to the clinical manifestations of severe coronavirus disease 2019 (COVID-19). Ravulizumab, a humanized monoclonal antibody that binds with high affinity to complement protein C5 and inhibits terminal complement activation, is being evaluated as a treatment for COVID-19-related severe pneumonia, acute lung injury, and acute respiratory distress syndrome in an ongoing phase 3 randomized controlled trial (ALXN1210-COV-305). To address the overactivation of terminal complement in severe COVID-19 compared to the diseases in which ravulizumab is currently approved, a modified dosing regimen was adopted. This analysis evaluates preliminary pharmacokinetic/pharmacodynamic data to confirm the modified dosing regimen. METHODS: Weight-based ravulizumab doses were administered on days 1, 5, 10, and 15. Serum levels of ravulizumab and free C5 were measured before and after administration of ravulizumab and any time on day 22. Free C5 levels < 0.5 µg/mL indicate complete C5 inhibition. The pharmacokinetic target was defined as ravulizumab concentrations at the end of the dosing interval > 175 µg/mL, the concentration above which C5 is completely inhibited. RESULTS: Twenty-two patients were included in this evaluation. At baseline, mean C5 concentration was 240 ± 67 µg/mL. In all patients and at all individual timepoints after the first dose was administered, ravulizumab concentrations remained > 175 µg/mL and free C5 concentrations remained < 0.5 µg/mL. CONCLUSION: High levels of baseline C5 observed in patients with severe COVID-19 contribute to the growing body of evidence that suggests this disease is marked by amplification of terminal complement activation. Data from this preliminary pharmacokinetic/pharmacodynamic evaluation of 22 patients with severe COVID-19 show that the modified ravulizumab dosing regimen achieved immediate and complete terminal complement inhibition, which can be sustained for up to 22 days. These data support the continued use of this dosage regimen in the ongoing phase 3 study. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT04369469.

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While many people have no or mild COVID-19 symptoms, a small number of people become very sick and require hospitalization in intensive care units. One part of their immune system, known as complement, overreacts and attacks the lungs and other organs. Researchers are looking for a way to keep the immune system from attacking the body instead of protecting it. Ravulizumab is a medication currently used to do this in other diseases. Ravulizumab is being studied to see if it can reduce the destructive and deadly effects of the coronavirus infection. In this evaluation, ravulizumab effectively reduced complement in patients with severe COVID-19.

RESUMEN

BACKGROUND: The risk of eculizumab therapy discontinuation in patients with atypical hemolytic uremic syndrome (aHUS) is unclear. The main objective of this study was to analyze the risk of aHUS relapse after eculizumab interruption due to drug shortage in Brazil. METHODS: We screened all the registered dialysis centers in Brazil (n = 800), willing to participate in the aHUS Brazilian shortage cohort, through electronic mail and formal invitation by the Brazilian Society of Nephrology. We included patients with aHUS whose eculizumab therapy underwent unplanned discontinuation for at least 30 days between January 1st, 2016 and December 31st, 2019 during the maintenance phase of treatment. Relapse was defined by the development of thrombocytopenia, hemolytic anemia, acute kidney injury or thrombotic microangiopathy (TMA) in a kidney biopsy. RESULTS: We analyzed 25 episodes of exposure to risk of relapse, from 24 patients. Median age was 33 (6-53) years, 18 (72%) were female, 9 (36%) had a functioning renal graft, 5 (20%) were undergoing dialysis. CFH variant was found in 8 (32%) episodes. There were 11 relapses. The risk of relapse was 34%, 44.5% and 58% at 114, 150 and 397 days, respectively. No baseline variable was related to relapse in Cox multivariate analysis, including CFH variant. CONCLUSIONS: In this study, the cumulative incidence of aHUS relapse at 397 days was 58% after eculizumab interruption. The presence of complement variant does not seem to be associated with a higher relapse rate. The eculizumab interruption was deemed not safe, considering that the rate of relapse was high.

Asunto(s)

Síndrome Hemolítico Urémico Atípico , Microangiopatías Trombóticas , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Síndrome Hemolítico Urémico Atípico/tratamiento farmacológico , Brasil , Femenino , Humanos

RESUMEN

BACKGROUND: Although established therapies are effective in most patients with generalized myasthenia gravis (gMG), some patients do not respond or they experience intolerable adverse events, highlighting the need for better tolerated, targeted therapies for treatment-refractory gMG. OBJECTIVE: To describe real-world experience with eculizumab in patients with treatment-refractory acetylcholine receptor antibody-positive (AChR+) gMG. METHODS: Retrospective chart review of 15 patients with treatment-refractory AChR+ gMG treated for 12 months with eculizumab (900 mg/week for 4 weeks then 1200 mg every 2 weeks). Outcome measures were Myasthenia Gravis-Activities of Daily Living (MG-ADL) scores, number of exacerbations, single-breath count test (SBCT) score, medication changes, selected Quantitative Myasthenia Gravis (QMG) evaluations, and adverse events. Data collected at 3-monthly intervals for 12 months before and after eculizumab initiation were analyzed. RESULTS: Clinically meaningful reductions in total MG-ADL scores were observed at 3 months following eculizumab initiation and maintained up to 12 months in all patients. After 12 months' eculizumab treatment, there was a significant reduction in the number of acute exacerbations; mean (SD) SBCT score improved from 28.13 (0.33) to 50.26 (2.86); all patients achieved a 'none' or 'mild' rating for QMG evaluations; all patients reduced their daily prednisone dose; and nine patients had discontinued pyridostigmine. At the end of treatment, intravenous immunoglobulin was discontinued in all six patients receiving this therapy at eculizumab initiation. Eculizumab was well tolerated. CONCLUSIONS: This real-world study demonstrated improvement in outcome measures and decreased concomitant drug requirement within 12 months of eculizumab initiation in patients with treatment-refractory AChR+ gMG.

Asunto(s)

Anticuerpos Monoclonales Humanizados/uso terapéutico , Miastenia Gravis/tratamiento farmacológico , Receptores Colinérgicos/inmunología , Actividades Cotidianas , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Retrospectivos , Adulto Joven

RESUMEN

This manuscript presents quantitative findings on the actual effectiveness of terminal complement component 5 (C5) inhibitors and complement component 1 (C1) esterase inhibitors through their formal and common "off-label" (compassionate) indications. The results emanated from pairwise and network meta-analyses to present evidence until September 2019. Clinical trials (CT) and real-life non-randomized studies of the effects of interventions (NRSI) are consistent on the benefits of C5 inhibitors and of the absence of effects of C1 esterase inhibitors (n = 7484): Mathematically, eculizumab (surface under the cumulative ranking area (SUCRA) >0.6) and ravulizumab (SUCRA ≥ 0.7) were similar in terms of their protective effect on hemolysis in paroxysmal nocturnal hemoglobinuria (PNH), thrombotic microangiopathy (TMA) in atypical hemolytic uremic syndrome (aHUS), and acute kidney injury (AKI) in aHUS, in comparison to pre-/off-treatment state and/or placebo (SUCRA < 0.01), and eculizumab was efficacious on thrombotic events in PNH (odds ratio (OR)/95% confidence interval (95% CI) in CT and real-life NRSI, 0.07/0.03 to 0.19, 0.24/0.17 to 0.33) and chronic kidney disease (CKD) occurrence/progression in PNH (0.31/0.10 to 0.97, 0.66/0.44 to 0.98). In addition, meta-analysis on clinical trials shows that eculizumab mitigates a refractory generalized myasthenia gravis (rgMG) crisis (0.29/0.13 to 0.61) and prevents new acute antibody-mediated rejection (AMR) episodes in kidney transplant recipients (0.25/0.13 to 0.49). The update of findings from this meta-analysis will be useful to promote a better use of complement inhibitors, and to achieve personalization of treatments with this class of drugs.

RESUMEN

BACKGROUND: The role of the complement cascade in acetylcholine receptor antibody-negative (AChR-) myasthenia gravis (MG) is unclear. OBJECTIVE: To assess the efficacy and tolerability of eculizumab (terminal complement inhibitor) in patients with AChR-MG. METHODS: Retrospective chart review of data from six patients treated for 12 months with eculizumab for treatment-refractory, AChR-(by radioimmunoassay) generalized MG (gMG). The eculizumab dose was 900 mg/week for 4 weeks then 1200 mg every 2 weeks. Outcome measures were Myasthenia Gravis-Activities of Daily Living (MG-ADL) scores, number of exacerbations, and qualitative physical assessments based on selected items of the Quantitative Myasthenia Gravis evaluation (ptosis, double vision, eye closure, duration of ability to stretch out limbs). RESULTS: All patients were female (mean age, 50.8 years). In the 12 months before eculizumab initiation, all measures were relatively stable. After its initiation, clinically meaningful reductions (≥2 points) in total MG-ADL scores were observed before or at 5 months and were maintained to Month 12 in all patients; mean (standard deviation [SD]) scores were 11.3 (0.9) and 5.0 (0.9), respectively. There was also a reduction in the mean (SD) number of exacerbations per patient, from 2.8 (1.2) to 0.3 (0.5) in the 12 months before and after eculizumab initiation, respectively. Physical assessment ratings were improved in all patients. Adverse events were reported in four patients, but all were mild and none were treatment-related. CONCLUSIONS: This small retrospective analysis provides preliminary evidence for the efficacy of eculizumab in treatment-refractory gMG that was AChR-according to radioimmunoassay. Larger, more robust studies are warranted to evaluate this further.

Asunto(s)

Anticuerpos Monoclonales Humanizados/farmacología , Inactivadores del Complemento/farmacología , Miastenia Gravis/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud , Actividades Cotidianas , Adulto , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Inactivadores del Complemento/administración & dosificación , Inactivadores del Complemento/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Miastenia Gravis/inmunología , Receptores Colinérgicos/inmunología , Estudios Retrospectivos

RESUMEN

Atypical haemolytic uraemic syndrome (aHUS) is a severe, life-threatening condition that requires early recognition and urgent treatment. In aHUS rare genetic variants in CFH, CFI, CD46, C3 and CFB predispose to complement over activation. This case describes a case of aHUS in which there was a strong temporal association between disease onset and the use of smoked cocaine. The patient was found to have a rare genetic variant in the CFI gene which may have been unmasked by first-time exposure to cocaine. The patient stabilized and improved with early administration of eculizumab, supporting the notion of an underlying immunological pathogenesis and the importance of early intervention.

Asunto(s)

Anticuerpos Monoclonales Humanizados/administración & dosificación , Síndrome Hemolítico Urémico Atípico , Fumar Cocaína , Factor I de Complemento/genética , Insuficiencia Renal , Trombocitopenia , Síndrome Hemolítico Urémico Atípico/genética , Síndrome Hemolítico Urémico Atípico/fisiopatología , Síndrome Hemolítico Urémico Atípico/terapia , Biopsia/métodos , Fumar Cocaína/efectos adversos , Fumar Cocaína/prevención & control , Humanos , Riñón/patología , Riñón/fisiopatología , Pruebas de Función Renal/métodos , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Diálisis Renal/métodos , Insuficiencia Renal/diagnóstico , Insuficiencia Renal/terapia , Trombocitopenia/diagnóstico , Trombocitopenia/etiología , Trombocitopenia/terapia , Microangiopatías Trombóticas/etiología , Microangiopatías Trombóticas/patología , Resultado del Tratamiento

RESUMEN

BACKGROUND: Atypical hemolytic-uremic syndrome is caused by a thrombotic microangiopathy and manifests itself with hemolytic anemia, thrombocytopenia, and organ ischemia. Its etiology is a mutation affecting the genes encoding for proteins of the complement system. Early treatment with eculizumab (8.6 months from the moment of presentation), a humanized monoclonal antibody against complement, is shown to be effective in controlling symptoms and reversing organ damage. We present a patient with a mutation not previously described in the literature. Late treatment with eculizumab resulted in a good therapeutic response, eliminating the need for peritoneal dialysis. CASE PRESENTATION: A 34-year-old woman showed symptoms and laboratory findings consistent with atypical hemolytic-uremic syndrome. Genetic analysis revealed an unusual mutation of the complement regulatory gene not seen previously. Due to unavailability of eculizumab at the time of presentation, conventional treatment was started with poor response. Late initiation of eculizumab resulted in discontinuation of peritoneal dialysis and yielded a good and sustained clinical response. CONCLUSIONS: This case shows that eculizumab treatment for patients with atypical hemolytic-uremic syndrome, even when initiated many months after beginning on dialysis, might offer substantial benefits and improve the patients' quality of life.

RESUMEN

BACKGROUND AND OBJECTIVES: The complement inhibitor eculizumab has dramatically improved the outcome of atypical hemolytic uremic syndrome. However, the optimal duration of eculizumab treatment in atypical hemolytic uremic syndrome remains debated. We report on the French atypical hemolytic uremic syndrome working group's first 2-year experience with eculizumab discontinuation in patients with atypical hemolytic uremic syndrome. DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS: Using the French atypical hemolytic uremic syndrome registry database, we retrospectively identified all dialysis-free patients with atypical hemolytic uremic syndrome who discontinued eculizumab between 2010 and 2014 and reviewed their relevant clinical and biologic data. The decision to discontinue eculizumab was made by the clinician in charge of the patient. All patients were closely monitored by regular urine dipsticks and blood tests. Eculizumab was rapidly (24-48 hours) restarted in case of relapse. RESULTS: Among 108 patients treated with eculizumab, 38 patients (nine children and 29 adults) discontinued eculizumab (median treatment duration of 17.5 months). Twenty-one patients (55%) carried novel or rare complement genes variants. Renal recovery under eculizumab was equally good in patients with and those without complement gene variants detected. After a median follow-up of 22 months, 12 patients (31%) experienced atypical hemolytic uremic syndrome relapse. Eight of 11 patients (72%) with complement factor H variants, four of eight patients (50%) with membrane cofactor protein variants, and zero of 16 patients with no rare variant detected relapsed. In relapsing patients, early reintroduction (≤48 hours) of eculizumab led to rapid (<7 days) hematologic remission and a return of serum creatinine to baseline level in a median time of 26 days. At last follow-up, renal function remained unchanged in nonrelapsing and relapsing patients compared with baseline values before eculizumab discontinuation. CONCLUSIONS: Pathogenic variants in complement genes were associated with higher risk of atypical hemolytic uremic syndrome relapse after eculizumab discontinuation. Prospective studies are needed to identify biomarkers predictive of relapse and determine the best strategy of retreatment in relapsing patients.

Asunto(s)

Anticuerpos Monoclonales Humanizados/uso terapéutico , Síndrome Hemolítico Urémico Atípico/tratamiento farmacológico , Síndrome Hemolítico Urémico Atípico/genética , Proteínas del Sistema Complemento/genética , Adolescente , Adulto , Anciano , Síndrome Hemolítico Urémico Atípico/fisiopatología , Niño , Preescolar , Factor H de Complemento/genética , Femenino , Estudios de Seguimiento , Humanos , Masculino , Proteína Cofactora de Membrana/genética , Persona de Mediana Edad , Recurrencia , Privación de Tratamiento , Adulto Joven

RESUMEN

The complement (C) cascade is an ancient system of proteins whose primary role is to initiate and modulate immune responses. During C activation, circulating proteins are cleaved and nascent cleavage fragments participate in a broad range of downstream innate and adaptive immune functions. Although the majority of these functions are either homeostatic or protective, a large body of experimental and clinical evidence also highlights a central role for the C system in the pathogenesis of many types of glomerular disease. From classic pathway activation in lupus nephritis to alternative pathway dysregulation in C3 glomerulopathy, our understanding of the spectrum of C involvement in kidney disease has expanded greatly in recent years. However, the characteristics that make the glomerulus so uniquely susceptible to C-mediated injury are not fully understood, and this remains an area of ongoing investigation. Several C inhibitors have been approved for clinical use, and additional C inhibitory drugs are in development. The use of these drugs in patients with kidney disease will expand our understanding of the benefits and limitations of C inhibition.

Asunto(s)

Activación de Complemento , Proteínas del Sistema Complemento/metabolismo , Enfermedades Renales/metabolismo , Glomérulos Renales , Animales , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Humanos , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/patología , Glomérulos Renales/patología