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1.
Adv Kidney Dis Health ; 31(3): 255-264, 2024 May.
Article in English | MEDLINE | ID: mdl-39004465

ABSTRACT

Thrombotic microangiopathy (TMA) is a pathological lesion that occurs due to endothelial injury. It can be seen in a heterogenous group of disorders, typically characterized by microangiopathic hemolytic anemia, thrombocytopenia, and end-organ ischemia. TMA can also be renal limited with no systemic manifestations. There are multiple etiologies of a TMA with complement activation being a core underlying mechanism, although the nature and extent of complement involvement can vary. A further complicated factor is the cross talk between complement, neutrophils, and coagulation pathways in the pathophysiology of TMAs. Therefore, a thorough and systematic clinical history and laboratory evaluation are critical to establish the cause and pathophysiology of a TMA. Furthermore, TMAs are associated with significant morbidity and mortality, and timely diagnosis is key for appropriate management and to prevent end-stage kidney disease and other associated complications. In this review, we focus on the pathology, mechanisms, diagnostic work up and treatment of TMAs associated with various etiologies. We also define the complement evaluations that should be conducted in these patients and further highlight the currently approved complement therapies as well as others in the pipeline.


Subject(s)
Thrombotic Microangiopathies , Humans , Thrombotic Microangiopathies/diagnosis , Thrombotic Microangiopathies/therapy , Thrombotic Microangiopathies/pathology , Thrombotic Microangiopathies/physiopathology , Complement Activation , Kidney/pathology , Kidney/immunology , Kidney/physiopathology , Complement System Proteins/immunology , Complement System Proteins/metabolism
2.
Ann Acad Med Singap ; 53(6): 371-385, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38979993

ABSTRACT

Introduction: Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematologic disease characterised by intravascular haemolysis, thrombophilia and bone marrow failure. There is a lack of established clinical guidance on the screening, diagnosis and manage-ment of PNH in Singapore. A relatively low level of awareness among healthcare professionals regarding PNH manifestations further contributes to diagnostic delays. Additionally, limited access to complement inhibitors, like eculizumab, may delay treatment and impact patient outcomes. Method: Nine haematologists from different institu-tions in Singapore convened to formulate evidence-based consensus recommendations for optimising the diagnosis and management of patients with PNH and improving access to novel treatments. The experts reviewed the existing literature and international guidelines published from January 2010 to July 2023, focusing on 7 clinical questions spanning PNH screening, diagnostic criteria, investigations, treatment and monitoring of subclinical and classic disease, PNH with underlying bone marrow disorders, and PNH in pregnancy. A total of 181 papers were reviewed to formulate the statements. All experts voted on the statements via 2 rounds of Delphi and convened for an expert panel discussion to finetune the recommendations. Results: Sixteen statements have been formulated for optimising the screening, diagnosis and management of PNH. Upon confirmation of PNH diagnosis, individuals with active haemolysis and/or thrombosis should be considered for anti-complement therapy, with eculizumab being the only approved drug in Singapore. Conclusion: The current recommendations aim to guide the clinicians in optimising the screening, diagnosis and management of PNH in Singapore.


Subject(s)
Antibodies, Monoclonal, Humanized , Hemoglobinuria, Paroxysmal , Female , Humans , Male , Pregnancy , Antibodies, Monoclonal, Humanized/therapeutic use , Complement Inactivating Agents/therapeutic use , Consensus , Delphi Technique , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/therapy , Pregnancy Complications, Hematologic/diagnosis , Pregnancy Complications, Hematologic/therapy , Pregnancy Complications, Hematologic/drug therapy , Singapore
3.
Expert Rev Hematol ; 17(7): 361-374, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38841813

ABSTRACT

INTRODUCTION: Comprehensive information about atypical hemolytic uremic syndrome (aHUS) is relatively scarce outside of Europe and North America. This narrative review assembles available published data about the clinical presentation and management of aHUS in Latin America. AREAS COVERED: A search conducted in February 2023 of the MEDLINE (from inception), Embase (from inception), and LILACS/IBECS (1950 to 2023) databases using search terms 'atypical hemolytic uremic syndrome' and 'Latin America' and their variations retrieved 51 records (full papers and conference abstracts) published in English, Spanish, or Portuguese. After de-duplication, manual screening of titles/abstracts and addition of author-known articles, 25 articles were included of which 17 (68%) are full papers. All articles were published during the years 2013-2022. Articles include cohort studies, a registry analysis, and case reports from Argentina, Brazil, Chile and Columbia. Overall, Latin American patients with aHUS present the classic epidemiological, clinical, and genetic characteristics associated with this condition as described in other world regions. Depending on the country and time of reporting, aHUS in Latin America was treated mainly with plasma therapy and/or eculizumab. Where reported, eculizumab substantially improved aHUS-related outcomes in almost all adult and pediatric patients. EXPERT OPINION: Eculizumab has dramatically altered the natural course of aHUS, improving prognosis and patient outcomes. Addressing economic challenges and investing in healthcare infrastructure will be essential to implement strategies for timely detection and early treatment of aHUS in Latin America.


Subject(s)
Atypical Hemolytic Uremic Syndrome , Disease Management , Humans , Latin America/epidemiology , Atypical Hemolytic Uremic Syndrome/therapy , Atypical Hemolytic Uremic Syndrome/diagnosis , Atypical Hemolytic Uremic Syndrome/epidemiology , Antibodies, Monoclonal, Humanized/therapeutic use
5.
Arch Pharm Res ; 47(6): 538-557, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38902481

ABSTRACT

Age-related macular degeneration (AMD) is the leading cause of vision loss in senior adults. The disease can be categorized into two types: wet AMD and dry AMD. Wet AMD, also known as exudative or neovascular AMD, is less common but more severe than dry AMD and is responsible for 90% of the visual impairment caused by AMD and affects 20 million people worldwide. Current treatment options mainly involve biologics that inhibit the vascular endothelial growth factor or complement pathways. However, these treatments have limitations such as high cost, injection-related risks, and limited efficacy. Therefore, new therapeutic targets and strategies have been explored to improve the outcomes of patients with AMD. A promising approach is the use of small-molecule drugs that modulate different factors involved in AMD pathogenesis, such as tyrosine kinases and integrins. Small-molecule drugs offer advantages, such as oral administration, low cost, good penetration, and increased specificity for the treatment of wet and dry AMD. This review summarizes the current status and prospects of small-molecule drugs for the treatment of wet AMD. These advances are expected to support the development of effective and targeted treatments for patients with AMD.


Subject(s)
Macular Degeneration , Humans , Macular Degeneration/drug therapy , Small Molecule Libraries/pharmacology , Animals , Angiogenesis Inhibitors/therapeutic use , Angiogenesis Inhibitors/pharmacology , Angiogenesis Inhibitors/administration & dosage , Wet Macular Degeneration/drug therapy , Drug Development/methods , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/metabolism
6.
Res Pract Thromb Haemost ; 8(4): 102416, 2024 May.
Article in English | MEDLINE | ID: mdl-38812989

ABSTRACT

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hematologic disease characterized by complement-mediated hemolysis and thrombosis. Complement component 5 (C5) inhibitors have decreased PNH-related thrombosis rates and reduced mortality compared with those of age-matched controls. A small but significantly increased risk of life-threatening Neisseria infections, especially N meningitidis, represents a long-term safety risk of complement inhibition. Objectives: To evaluate the rates of thrombosis and meningococcal infections in patients with PNH treated with the complement component 3-targeted therapy pegcetacoplan. Methods: Cumulative patient-year exposure to pegcetacoplan was calculated, and thrombotic events and meningococcal infections were reviewed in 7 clinical trials and in the postmarketing setting. The clinical trial protocols and pegcetacoplan labeling required vaccination against Streptococcus pneumoniae, N meningitidis, and Haemophilus influenzae before pegcetacoplan use; the label allowed for prophylactic antibiotic use if pegcetacoplan must be administered before vaccination. Results: As of November 13, 2022, 464 patients with PNH had 619.4 patient-years of pegcetacoplan exposure in completed/ongoing clinical trials and the postmarketing setting. Seven thrombotic events were reported: 5 in clinical trials (2 in the same patient) and 2 in the postmarketing setting. The overall thrombosis rate was 1.13 events per 100 patient-years (clinical trials: 1.22 events/100 patient-years in 409.4 years; postmarketing: 0.95 events/100 patient-years in 210.0 years). No infections with meningococcal bacteria were reported. Conclusion: Event rates for thrombosis were comparable between pegcetacoplan and previously reported rates of C5 inhibitors in patients with PNH, and no cases of meningococcal infection were reported with pegcetacoplan. Continued follow-up is required.

7.
Int J Mol Sci ; 25(7)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38612407

ABSTRACT

A small fraction of people vaccinated with mRNA-lipid nanoparticle (mRNA-LNP)-based COVID-19 vaccines display acute or subacute inflammatory symptoms whose mechanism has not been clarified to date. To better understand the molecular mechanism of these adverse events (AEs), here, we analyzed in vitro the vaccine-induced induction and interrelations of the following two major inflammatory processes: complement (C) activation and release of proinflammatory cytokines. Incubation of Pfizer-BioNTech's Comirnaty and Moderna's Spikevax with 75% human serum led to significant increases in C5a, sC5b-9, and Bb but not C4d, indicating C activation mainly via the alternative pathway. Control PEGylated liposomes (Doxebo) also induced C activation, but, on a weight basis, it was ~5 times less effective than that of Comirnaty. Viral or synthetic naked mRNAs had no C-activating effects. In peripheral blood mononuclear cell (PBMC) cultures supplemented with 20% autologous serum, besides C activation, Comirnaty induced the secretion of proinflammatory cytokines in the following order: IL-1α < IFN-γ < IL-1ß < TNF-α < IL-6 < IL-8. Heat-inactivation of C in serum prevented a rise in IL-1α, IL-1ß, and TNF-α, suggesting C-dependence of these cytokines' induction, although the C5 blocker Soliris and C1 inhibitor Berinert, which effectively inhibited C activation in both systems, did not suppress the release of any cytokines. These findings suggest that the inflammatory AEs of mRNA-LNP vaccines are due, at least in part, to stimulation of both arms of the innate immune system, whereupon C activation may be causally involved in the induction of some, but not all, inflammatory cytokines. Thus, the pharmacological attenuation of inflammatory AEs may not be achieved via monotherapy with the tested C inhibitors; efficacy may require combination therapy with different C inhibitors and/or other anti-inflammatory agents.


Subject(s)
COVID-19 , Complement Inactivating Agents , Nanoparticles , Humans , Liposomes , COVID-19 Vaccines/adverse effects , Leukocytes, Mononuclear , Cytokines , Tumor Necrosis Factor-alpha , BNT162 Vaccine , Complement Activation , Lipids
8.
Int J Lab Hematol ; 46 Suppl 1: 43-54, 2024 May.
Article in English | MEDLINE | ID: mdl-38622956

ABSTRACT

Complement inhibitors are the mainstay of paroxysmal nocturnal hemoglobinuria (PNH) treatment. The anti-C5 monoclonal antibody eculizumab was the first treatment to improve hemolysis, thrombotic risk, and survival in PNH although at the price of a life-long intravenous fortnightly drug. Additionally, suboptimal response may occur in up to 2/3 of patients with persistent anemia due to incomplete control of intravascular hemolysis, development of upstream C3-mediated extravascular hemolysis (EVH), or concomitant bone marrow failure. Ravulizumab, a longer half-life anti-C5 developed from eculizumab, administered every 8 weeks, improved patient convenience, and reduced pharmacokinetic breakthrough hemolysis (BTH) by establishing more stable anti-C5 concentrations. More recently, several other anti-C5 compounds (crovalimab, pozelimab, tesidolumab, cemdisiran, zilucoplan, and coversin) are on study in clinical trials. Upstream inhibition of complement cascade was also explored with the anti-C3 pegcetacoplan, and with the alternative pathway inhibitors iptacopan (anti-factor B) and danicopan (anti-factor D). These drugs efficiently target EVH and are able to improve anemia and transfusion need in suboptimal responders to anti-C5. The route and schedule of administration (twice weekly subcutaneously for pegcetacoplan and twice or thrice oral daily dosing for iptacopan and danicopan, respectively) are very convenient but pose novel issues regarding adherence. Additionally, both anti-C5 and upstream inhibitors do not resolve the unmet need of pharmacodynamic BTH events due to complement amplifying conditions such as infections, traumas, and surgery. In this review, we will recapitulate PNH physiopathology, clinical presentation, and diagnosis and describe available and developing drugs that will lead to a precision medicine approach for this rare though heterogenous disease.


Subject(s)
Antibodies, Monoclonal, Humanized , Complement Inactivating Agents , Hemoglobinuria, Paroxysmal , Hemoglobinuria, Paroxysmal/drug therapy , Humans , Complement Inactivating Agents/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Complement C5/antagonists & inhibitors , Hemolysis/drug effects
9.
J Drug Target ; 32(5): 485-498, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38491993

ABSTRACT

The complement is an important arm of the innate immune system, once activated, the complement system rapidly generates large quantities of protein fragments that are potent mediators of inflammation. Recent studies have shown that over-activated complement is the main proinflammatory system of autoimmune diseases (ADs). In addition, activated complements interact with autoantibodies, immune cells exacerbate inflammation, further worsening ADs. With the increasing threat of ADs to human health, complement-based immunotherapy has attracted wide attention. Nevertheless, efficient and targeted delivery of complement inhibitors remains a significant challenge owing to their inherent poor targeting, degradability, and low bioavailability. Nanosystems offer innovative solutions to surmount these obstacles and amplify the potency of complement inhibitors. This prime aim to present the current knowledge of complement in ADs, analyse the function of complement in the pathogenesis and treatment of ADs, we underscore the current situation of nanosystems assisting complement inhibitors in the treatment of ADs. Considering technological, physiological, and clinical validation challenges, we critically appraise the challenges for successfully translating the findings of preclinical studies of these nanosystem assisted-complement inhibitors into the clinic, and future perspectives were also summarised. (The graphical abstract is by BioRender.).


Subject(s)
Autoimmune Diseases , Complement Inactivating Agents , Complement System Proteins , Humans , Autoimmune Diseases/drug therapy , Autoimmune Diseases/immunology , Complement Inactivating Agents/administration & dosage , Complement Inactivating Agents/pharmacology , Animals , Complement System Proteins/immunology , Nanoparticles , Complement Activation/drug effects , Drug Delivery Systems , Immunotherapy/methods
10.
Eur J Intern Med ; 124: 22-31, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38461065

ABSTRACT

The Complement System is an evolutionarily conserved component of immunity that plays a key role in host defense against infections and tissue homeostasis. However, the dysfunction of the Complement System can result in tissue damage and inflammation, thereby contributing to the development and progression of various renal diseases, ranging from atypical Hemolytic Uremic Syndrome to glomerulonephritis. Therapeutic interventions targeting the complement system have demonstrated promising results in both preclinical and clinical studies. Currently, several complement inhibitors are being developed for the treatment of complement-mediated renal diseases. This review aims to summarize the most recent insights into complement activation and therapeutic inhibition in renal diseases. Furthermore, it offers potential directions for the future rational use of complement inhibitor drugs in the context of renal diseases.


Subject(s)
Complement Activation , Complement Inactivating Agents , Complement System Proteins , Disease Progression , Kidney Diseases , Humans , Complement System Proteins/immunology , Kidney Diseases/immunology , Kidney Diseases/etiology , Complement Inactivating Agents/therapeutic use , Complement Inactivating Agents/pharmacology , Animals , Atypical Hemolytic Uremic Syndrome/immunology , Glomerulonephritis/immunology
11.
Clin Microbiol Infect ; 30(5): 611-618, 2024 May.
Article in English | MEDLINE | ID: mdl-38182048

ABSTRACT

BACKGROUND: Immunomodulatory therapy has been extensively studied in randomized clinical trials for the treatment of patients hospitalized for COVID-19 with inconsistent findings. Guideline committees, reviewing the same clinical trial data, have generated different recommendations for immunomodulatory therapy. OBJECTIVES: We hypothesize that trial design differences, specifically whether the study utilized an open-label or placebo-controlled design, accounted for the inconsistent mortality effects reported in clinical trials of immunomodulator therapies for COVID-19. SOURCES: We reviewed COVID-19 treatment guidelines (World Health Organization [WHO], Infectious Diseases Society of America [IDSA] and The National Institutes of Health [NIH]) and identified the meta-analyses associated with glucocorticoids, IL-6 inhibitors, JAK kinase inhibitors, and complement C5a inhibitors that were available to the guideline authors at the time recommendations were either made or updated. CONTENT: We identified a meta-analysis for each of the immunomodulator classes that are included in current COVID-19 treatment guidelines: glucocorticoids [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), IL-6 antagonists [WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group; Shankar-Hari M, Vale CL, Godolphin PJ, Fisher D, Higgins JPT, et al. Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19: A meta-analysis. JAMA. 2021;326:499-518] (cited 419), JAK inhibitors [Kramer A, Prinz C, Fichtner F, Fischer AL, Thieme V, Grundeis F, et al. Janus kinase inhibitors for the treatment of COVID-19. Cochrane Database Syst Rev. 2022;6:CD015209] (cited 34), and complement C5a inhibitors [Tsai CL, Lai CC, Chen CY, Lee HS. The efficacy and safety of complement C5a inhibitors for patients with severe COVID-19: A systematic review and meta-analysis. Expert Rev Anti Infect Ther. 2023;21:77-86] (cited 1). Using the same randomized clinical trials, we evaluated the four meta-analyses accounting for trial design: placebo-controlled or open-label. Glucocorticoids (Risk Ratio [RR] 0.91 [95% CI, 0.49-1.69]), IL-6 inhibitors sarilumab (RR 1.17 [95% CI, 0.96-01.43]), and tocilizumab (RR 0.95 [95% CI, 0.76-1.19]) did not reduce mortality in placebo-controlled trials, whereas baricitinib did confer a large survival benefit (RR 0.65 [95% CI, 0.52-0.81]). The complement C5a inhibitor, vilobelimab, also reduced mortality in a single placebo-controlled trial (RR 0.76 [95% CI, 0.57-1.0]). IMPLICATIONS: Placebo-controlled trial evidence indicates that baricitinib should be the first choice immunomodulator for patients hospitalized for COVID-19 who require any form of oxygen support-low- or high-flow oxygen, non-invasive or invasive ventilation. Vilobelimab warrants study in a large placebo-controlled trial. Treatment guidelines for future pandemics should prioritize the results of placebo-controlled trials.


Subject(s)
COVID-19 Drug Treatment , SARS-CoV-2 , Humans , Glucocorticoids/therapeutic use , Immunomodulating Agents/therapeutic use , COVID-19/mortality , Randomized Controlled Trials as Topic , Interleukin-6/antagonists & inhibitors , Janus Kinase Inhibitors/therapeutic use , Immunomodulation , Practice Guidelines as Topic , Immunologic Factors/therapeutic use
12.
Insect Sci ; 2024 Jan 21.
Article in English | MEDLINE | ID: mdl-38246860

ABSTRACT

In arthropods, hematophagy has arisen several times throughout evolution. This specialized feeding behavior offered a highly nutritious diet obtained during blood feeds. On the other hand, blood-sucking arthropods must overcome problems brought on by blood intake and digestion. Host blood complement acts on the bite site and is still active after ingestion, so complement activation is a potential threat to the host's skin feeding environment and to the arthropod gut enterocytes. During evolution, blood-sucking arthropods have selected, either in their saliva or gut, anticomplement molecules that inactivate host blood complement. This review presents an overview of the complement system and discusses the arthropod's salivary and gut anticomplement molecules studied to date, exploring their mechanism of action and other aspects related to the arthropod-host-pathogen interface. The possible therapeutic applications of arthropod's anticomplement molecules are also discussed.

13.
Muscle Nerve ; 69(3): 368-372, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38205840

ABSTRACT

INTRODUCTION/AIMS: Myasthenia gravis (MG) is a rare, life-threatening immune-related adverse effect (irAE) of immune checkpoint inhibitor (ICI) treatment. C5-complement inhibitors are effective treatments for acetylcholine receptor antibody (AChR ab) positive generalized MG. We describe the use of eculizumab/ravulizumab in two patients with MG receiving concomitant pembrolizumab. METHODS: This was a retrospective review of two medical records. RESULTS: Patient 1: An 80-year-old male with recurrent, non-muscle invasive transitional cell carcinoma of the bladder developed ICI-induced AChR ab positive MG (ICI-MG), myositis, and myocarditis 2 weeks after the first dose of pembrolizumab. Myositis responded to corticosteroids. MG responded to eculizumab, followed by ravulizumab. He died of metastatic cancer 8 months later. Patient 2: A 58-year-old male had refractory thymoma-associated AChR ab-positive MG, which responded to eculizumab. He developed metastatic Merkel cell cancer necessitating pembrolizumab. MG remained stable on eculizumab. He had no irAEs for 22 months, with positron emission tomographic resolution of cancer. He then developed mild, indolent retinal vasculitis, which responded to prednisone. Discontinuation of pembrolizumab for 5 months resulted in cancer recurrence; pembrolizumab was resumed with peri-infusion pulse prednisone. MG remained stable and he continues eculizumab. DISCUSSION: In the first patient, eculizumab, followed by ravulizumab, improved ICI-MG. In the second patient, eculizumab treatment may have had a prophylactic effect on the development of ICI-induced irAEs. The effect of complement inhibition on cancer outcomes of ICI therapy is unknown. A possible biologic basis for complement inhibitors in reducing irAEs of ICI, especially in the presence of underlying autoimmune disease, merits evaluation.


Subject(s)
Myasthenia Gravis , Myositis , Humans , Male , Aged, 80 and over , Middle Aged , Prednisone/therapeutic use , Complement Inactivating Agents/therapeutic use , Neoplasm Recurrence, Local/complications , Myasthenia Gravis/chemically induced , Myasthenia Gravis/drug therapy , Myasthenia Gravis/complications , Myositis/complications
15.
Ther Adv Hematol ; 14: 20406207231216080, 2023.
Article in English | MEDLINE | ID: mdl-38105771

ABSTRACT

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired hematological disease. The development of complement inhibitors such as eculizumab, ravulizumab, and pegcetacoplan has revolutionized the management of PNH, leading to improvements in overall survival and quality of life for patients. Objectives: This systematic review aims to provide comprehensive evidence of the efficacy of complement inhibitors in relation to treatment duration. Design: This is a systematic review and meta-analysis. Data sources and methods: A thorough literature search was conducted in MEDLINE, EMBASE, and the Cochrane Library up to 3 May 2022. We included all prospective interventional studies including single-arm trials. The primary outcomes of interest were lactate dehydrogenase (LDH) levels, hemoglobin (Hb) concentrations, transfusion avoidance, and Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-F) scores. Results: Our study included a total of 27 studies, comprising 5 randomized controlled trials and 11 single-arm trials, with a total of 912 patients with PNH. We stratified the studies according to treatment duration, based on the most frequently reported period of 26 weeks. Our analysis showed that treatment-naïve patients who received complement inhibitors had a pooled estimate of a decrease in LDH levels from baseline by -1462.0 U/L (95% CI: -1735.6 to -1188.5) for treatment ⩽26 weeks and -1696.5 U/L (95% CI: -2122.7 to -1270.2) for treatment >26 weeks. The mean Hb levels were increased by 1.4 g/dL (95% CI: 0.5-2.3) and 1.9 g/dL (95% CI: 0.7-3.1) in each group. Treatment with any complement inhibitor prevented the need for transfusion in at least 50% of patients with PNH in all treatment periods. Clinically meaningful improvements in FACIT-F were observed both before and after 26 weeks, with a pooled estimate of 6.8 (95% CI: 6.0-7.6) and 9.5 (95% CI: 7.0-12.0), respectively. Conclusion: Our findings suggest that complement inhibitors can result in positive treatment outcomes and sustained benefits for patients with PNH.

16.
Eur J Pharm Biopharm ; 193: 227-240, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37949325

ABSTRACT

The complement system is a multicomponent and multifunctional arm of the innate immune system. Complement contributes to non-specific host defence and maintains homeostasis through multifaceted processes and pathways, including crosstalk with the adaptive immune system, the contact (coagulation) and the kinin systems, and alarmin high-mobility group box 1. Complement is also present intracellularly, orchestrating a wide range of housekeeping and physiological processes in both immune and nonimmune cells, thus showing its more sophisticated roles beyond innate immunity, but its roles are still controversial. Particulate drug carriers and nanopharmaceuticals typically present architectures and surface patterns that trigger complement system in different ways, resulting in both beneficial and adverse responses depending on the extent of complement activation and regulation as well as pathophysiological circumstances. Here we consider the role of complement system and complement regulations in host defence and evaluate the mechanisms by which nanoparticles trigger and modulate complement responses. Effective strategies for the prevention of nanoparticle-mediated complement activation are introduced and discussed.


Subject(s)
Complement System Proteins , Nanoparticles , Complement System Proteins/metabolism , Immunity, Innate , Complement Activation , Drug Carriers
17.
Front Immunol ; 14: 1269325, 2023.
Article in English | MEDLINE | ID: mdl-37854608

ABSTRACT

Paroxysmal nocturnal haemoglobinuria (PNH) is a rare acquired haematopoietic stem cell disease characterized by complement-mediated intravascular hemolysis, thrombosis, and bone marrow failure. Eculizumab and ravulizumab are anti-C5 monoclonal antibodies that reduce hemolysis, anaemia and thrombotic risk, but are associated with increased risk of infection with encapsulated bacteria, including Neisseria meningitidis. We report a case of life-threatening infection by non-groupable Neisseria meningitidis in a young PNH patient treated with ravulizumab. Despite prompt admission to the intensive care unit, microbe isolation was delayed due to the negativity of capsular antigens, and the patient required intubation, dialysis, and transfusion support for pancytopenia. Notably, PNH disease activity remained controlled and no additional anti-C5 doses were administered. Increasing awareness regarding septic risk in PNH patients on complement inhibitors despite vaccinations is pivotal. A warning about serotypes generally not pathogenetic and not covered by vaccination, such as non-capsulated forms, is emerging.


Subject(s)
Hemoglobinuria, Paroxysmal , Neisseria meningitidis , Pancytopenia , Sepsis , Thrombosis , Humans , Hemoglobinuria, Paroxysmal/diagnosis , Hemoglobinuria, Paroxysmal/drug therapy , Complement Inactivating Agents/therapeutic use , Hemolysis , Thrombosis/drug therapy , Sepsis/diagnosis , Sepsis/drug therapy , Sepsis/etiology
18.
Res Sq ; 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37886595

ABSTRACT

Alzheimer's disease (AD) is a complex neurodegenerative disease associated with memory decline, cognitive impairment, amyloid plaque formation and tau tangles. Neuroinflammation has been shown to be a precursor to apparent amyloid plaque accumulation and subsequent synaptic loss and cognitive decline. In this study, the ability of a novel, small molecule, T-ALZ01, to inhibit neuroinflammatory processes was analyzed. T-ALZ01, an inhibitor of complement component C1r, demonstrated a significant reduction in the levels of the inflammatory cytokines, IL-6 and TNF-α in vitro. An LPS-induced animal model, whereby animals were injected intraperitoneally with 0.5 mg/kg LPS, was used to analyze the effect of T-ALZ01 on neuroinflammation in vivo. Moreover, exosomes (nanosized, endogenous extracellular vehicles) were used as drug delivery vehicles to facilitate intranasal administration of T-ALZ01 across the blood-brain barrier. T-ALZ01 demonstrated significant reduction in degenerating neurons and the activation of resident microglia and astrocytes, as well as inflammatory markers in vivo. This study demonstrates a significant use of small molecule complement inhibitors via exosome drug delivery as a possible therapeutic in disorders characterized by neuroinflammation, such AD.

19.
BMC Res Notes ; 16(1): 244, 2023 Sep 30.
Article in English | MEDLINE | ID: mdl-37777762

ABSTRACT

OBJECTIVE: Geographic Atrophy (GA) is the advanced form of the non-neovascular ('dry') type of age-related macular degeneration (AMD) and responsible for one-quarter of legal blindness in the UK. New therapies delivered by intravitreal injection are in late-stage development, and two such therapies (pegcetacoplan (Syfovre) and avacincaptad pegol (Izervay)) have now been approved for clinical use by the US Food and Drug Administration. These therapies slow down, but do not stop or reverse, progression of GA and they may also increase the risk of developing the neovascular ('wet') type of AMD. Within a larger study exploring the acceptability of these new treatments to people living with GA, we developed a forced-choice exercise to evaluate how participants weigh up benefits and drawbacks of different treatment regimens. This research note reports quantitative and qualitative findings from this exercise. RESULTS: Twenty-eight participants took part in this exercise. The exercise demonstrated that participants were generally, although not unanimously, in favour of less frequent treatment for GA that was slightly less efficacious in terms of preserving visual function but presented a lower risk of developing wet AMD. Even among a small sample, the exercise demonstrated the highly personal and idiosyncratic decision-making processes influencing participants' choices of preferred hypothetical GA treatment.


Subject(s)
Geographic Atrophy , Macular Degeneration , Humans , Geographic Atrophy/drug therapy , Macular Degeneration/drug therapy
20.
Clin Exp Ophthalmol ; 51(8): 835-852, 2023 11.
Article in English | MEDLINE | ID: mdl-37737509

ABSTRACT

Age-related macular degeneration is a global disease with a significant societal impact. The advent of anti-vascular endothelial growth factor therapy (anti-VEGF) has revolutionised the treatment of neovascular age-related macular degeneration (nAMD). Dry age-related macular degeneration (dAMD) is being investigated for possible therapeutic options. The therapeutic categories undergoing clinical trials include complement pathway inhibitors, visual cycle modulators, reduction of toxic byproducts, antioxidative therapy, neuroprotective agents, laser therapy, surgical options, gene therapy, stem cell therapy, and miscellaneous treatments. Two intravitreal anti-complement factors (pegcetacoplan and avacincaptad pegol) have recently shown phase 3 clinical trial evidence of a reduction in the growth of geographic atrophy. In this review, we provide an update on treatment options currently undergoing clinical research trials for the management of dAMD and preventing the progression of Geographic Atrophy (GA).


Subject(s)
Geographic Atrophy , Macular Degeneration , Wet Macular Degeneration , Humans , Geographic Atrophy/therapy , Macular Degeneration/drug therapy , Angiogenesis Inhibitors/therapeutic use , Intravitreal Injections , Wet Macular Degeneration/drug therapy
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