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Journal of Investigational Allergology... Feb 2021Hereditary angioedema due to C1-esterase inhibitor deficiency (C1-INH-HAE) is a rare autosomal dominant disease. In the last decade, new drugs and new indications for... (Review)
Review
Hereditary angioedema due to C1-esterase inhibitor deficiency (C1-INH-HAE) is a rare autosomal dominant disease. In the last decade, new drugs and new indications for old drugs have played a role in the management of C1-INH-HAE. This review examines current therapy for C1-INH-HAE and provides a brief summary of drugs that are under development. Increased knowledge of the pathophysiology of C1-INH-HAE has been crucial for advances in the field, with inhibition of the kallikrein-kinin system (plasma kallikrein, activated factor XII) as a key area in the discovery of new drugs, some of which are already marketed for treatment of C1-INH-HAE. Pharmacological treatment is based on 3 pillars: treatment of acute angioedema attacks (on-demand treatment), short-term (preprocedure) prophylaxis, and long-term prophylaxis. The 4 drugs that are currently available for the treatment of acute angioedema attacks (purified plasma-derived human C1 esterase inhibitor concentrate, icatibant acetate, ecallantide, recombinant human C1 esterase inhibitor) are all authorized for self-administration, except ecallantide. Purified plasma-derived human C1 esterase inhibitor concentrate is the treatment of choice for short-term prophylaxis. Tranexamic acid, danazol, intravenous and subcutaneous nanofiltered purified plasma-derived human C1 esterase inhibitor concentrate, and lanadelumab can be used for long-term prophylaxis. New drugs are being investigated, mainly as long-term prophylaxis, and are aimed at blocking the kallikrein-kinin system by means of antiprekallikrein, antikallikrein, and anti-activated FXII action.
Topics: Angioedemas, Hereditary; Anti-Inflammatory Agents, Non-Steroidal; Bradykinin; Complement C1 Inhibitor Protein; Humans; Kallikrein-Kinin System; Peptides; Recombinant Proteins
PubMed: 33602658
DOI: 10.18176/jiaci.0653 -
JAMA Nov 2018Current treatments for long-term prophylaxis in hereditary angioedema have limitations. (Comparative Study)
Comparative Study Randomized Controlled Trial
IMPORTANCE
Current treatments for long-term prophylaxis in hereditary angioedema have limitations.
OBJECTIVE
To assess the efficacy of lanadelumab, a fully human monoclonal antibody that selectively inhibits active plasma kallikrein, in preventing hereditary angioedema attacks.
DESIGN, SETTING, AND PARTICIPANTS
Phase 3, randomized, double-blind, parallel-group, placebo-controlled trial conducted at 41 sites in Canada, Europe, Jordan, and the United States. Patients were randomized between March 3, 2016, and September 9, 2016; last day of follow-up was April 13, 2017. Randomization was 2:1 lanadelumab to placebo; patients assigned to lanadelumab were further randomized 1:1:1 to 1 of the 3 dose regimens. Patients 12 years or older with hereditary angioedema type I or II underwent a 4-week run-in period and those with 1 or more hereditary angioedema attacks during run-in were randomized.
INTERVENTIONS
Twenty-six-week treatment with subcutaneous lanadelumab 150 mg every 4 weeks (n = 28), 300 mg every 4 weeks (n = 29), 300 mg every 2 weeks (n = 27), or placebo (n = 41). All patients received injections every 2 weeks, with those in the every-4-week group receiving placebo in between active treatments.
MAIN OUTCOME AND MEASURES
Primary efficacy end point was the number of investigator-confirmed attacks of hereditary angioedema over the treatment period.
RESULTS
Among 125 patients randomized (mean age, 40.7 years [SD, 14.7 years]; 88 females [70.4%]; 113 white [90.4%]), 113 (90.4%) completed the study. During the run-in period, the mean number of hereditary angioedema attacks per month in the placebo group was 4.0; for the lanadelumab groups, 3.2 for the every-4-week 150-mg group; 3.7 for the every-4-week 300-mg group; and 3.5 for the every-2-week 300-mg group. During the treatment period, the mean number of attacks per month for the placebo group was 1.97; for the lanadelumab groups, 0.48 for the every-4-week 150-mg group; 0.53 for the every-4-week 300-mg group; and 0.26 for the every-2-week 300-mg group. Compared with placebo, the mean differences in the attack rate per month were -1.49 (95% CI, -1.90 to -1.08; P < .001); -1.44 (95% CI, -1.84 to -1.04; P < .001); and -1.71 (95% CI, -2.09 to -1.33; P < .001). The most commonly occurring adverse events with greater frequency in the lanadelumab treatment groups were injection site reactions (34.1% placebo, 52.4% lanadelumab) and dizziness (0% placebo, 6.0% lanadelumab).
CONCLUSIONS AND RELEVANCE
Among patients with hereditary angioedema type I or II, treatment with subcutaneous lanadelumab for 26 weeks significantly reduced the attack rate compared with placebo. These findings support the use of lanadelumab as a prophylactic therapy for hereditary angioedema. Further research is needed to determine long-term safety and efficacy.
TRIAL REGISTRATION
EudraCT Identifier: 2015-003943-20; ClinicalTrials.gov Identifier: NCT02586805.
Topics: Adolescent; Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Child; Double-Blind Method; Female; Hereditary Angioedema Types I and II; Humans; Injections, Subcutaneous; Male; Middle Aged; Plasma Kallikrein; Quality of Life; Young Adult
PubMed: 30480729
DOI: 10.1001/jama.2018.16773 -
The Journal of Allergy and Clinical... Jul 2021Berotralstat (BCX7353) is an oral, once-daily inhibitor of plasma kallikrein in development for the prophylaxis of hereditary angioedema (HAE) attacks. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Berotralstat (BCX7353) is an oral, once-daily inhibitor of plasma kallikrein in development for the prophylaxis of hereditary angioedema (HAE) attacks.
OBJECTIVE
Our aim was to determine the efficacy, safety, and tolerability of berotralstat in patients with HAE over a 24-week treatment period (the phase 3 APeX-2 trial).
METHODS
APeX-2 was a double-blind, parallel-group study that randomized patients at 40 sites in 11 countries 1:1:1 to receive once-daily berotralstat in a dose of 110 mg or 150 mg or placebo (Clinicaltrials.gov identifier NCT03485911). Patients aged 12 years or older with HAE due to C1 inhibitor deficiency and at least 2 investigator-confirmed HAE attacks in the first 56 days of a prospective run-in period were eligible. The primary efficacy end point was the rate of investigator-confirmed HAE attacks during the 24-week treatment period.
RESULTS
A total of 121 patients were randomized; 120 of them received at least 1 dose of the study drug (n = 41, 40, and 39 in the 110-mg dose of berotralstat, 150-mg of dose berotralstat, and placebo groups, respectively). Berotralstat demonstrated a significant reduction in attack rate at both 110 mg (1.65 attacks per month; P = .024) and 150 mg (1.31 attacks per month; P < .001) relative to placebo (2.35 attacks per month). The most frequent treatment-emergent adverse events that occurred more with berotralstat than with placebo were abdominal pain, vomiting, diarrhea, and back pain. No drug-related serious treatment-emergent adverse events occurred.
CONCLUSION
Both the 110-mg and 150-mg doses of berotralstat reduced HAE attack rates compared with placebo and were safe and generally well tolerated. The most favorable benefit-to-risk profile was observed at a dose of 150 mg per day.
Topics: Administration, Oral; Adult; Angioedemas, Hereditary; Double-Blind Method; Female; Humans; Male; Plasma Kallikrein; Prospective Studies; Pyrazoles; Treatment Outcome
PubMed: 33098856
DOI: 10.1016/j.jaci.2020.10.015 -
Hamostaseologie Feb 2022Blood coagulation is essential to maintain the integrity of a closed circulatory system (hemostasis), but also contributes to thromboembolic occlusion of vessels... (Review)
Review
Blood coagulation is essential to maintain the integrity of a closed circulatory system (hemostasis), but also contributes to thromboembolic occlusion of vessels (thrombosis). Thrombosis may cause deep vein thrombosis, pulmonary embolism, myocardial infarction, peripheral artery disease, and ischemic stroke, collectively the most common causes of death and disability in the developed world. Treatment for the prevention of thromboembolic diseases using anticoagulants such as heparin, coumarins, thrombin inhibitors, or antiplatelet drugs increase the risk of bleeding and are associated with an increase in potentially life-threatening hemorrhage, partially offsetting the benefits of reduced coagulation. Thus, drug development aiming at novel targets is needed to provide efficient and safe anticoagulation. Within the last decade, experimental and preclinical data have shown that some coagulation mechanisms principally differ in thrombosis and hemostasis. The plasma contact system protein factors XII and XI, high-molecular-weight kininogen, and plasma kallikrein specifically contribute to thrombosis, however, have minor, if any, role in hemostatic coagulation mechanisms. Inherited deficiency in contact system proteins is not associated with increased bleeding in humans and animal models. Therefore, targeting contact system proteins provides the exciting opportunity to interfere specifically with thromboembolic diseases without increasing the bleeding risk. Recent studies that investigated pharmacologic inhibition of contact system proteins have shown that this approach provides efficient and safe thrombo-protection that in contrast to classical anticoagulants is not associated with increased bleeding risk. This review summarizes therapeutic and conceptual developments for selective interference with pathological thrombus formation, while sparing physiologic hemostasis, that enables safe anticoagulation treatment.
Topics: Animals; Anticoagulants; Blood Coagulation; Factor XII; Hemostasis; Humans; Thrombosis
PubMed: 35196732
DOI: 10.1055/a-1717-7958 -
Frontiers in Immunology 2021Angioedema is a prevailing symptom in different diseases, frequently occurring in the presence of urticaria. Recurrent angioedema without urticaria (AE) can be... (Review)
Review
Angioedema is a prevailing symptom in different diseases, frequently occurring in the presence of urticaria. Recurrent angioedema without urticaria (AE) can be hereditary (HAE) and acquired (AAE), and several subtypes can be distinguished, although clinical presentation is quite similar in some of them. They present with subcutaneous and mucosal swellings, affecting extremities, face, genitals, bowels, and upper airways. AE is commonly misdiagnosed due to restricted access and availability of appropriate laboratorial tests. HAE with C1 inhibitor defect is associated with quantitative and/or functional deficiency. Although bradykinin-mediated disease results mainly from disturbance in the kallikrein-kinin system, traditionally complement evaluation has been used for diagnosis. Diagnosis is established by nephelometry, turbidimetry, or radial immunodiffusion for quantitative measurement of C1 inhibitor, and chromogenic assay or ELISA has been used for functional C1-INH analysis. Wrong handling of the samples can lead to misdiagnosis and, consequently, mistaken inappropriate approaches. Dried blood spot (DBS) tests have been used for decades in newborn screening for certain metabolic diseases, and there has been growing interest in their use for other congenital conditions. Recently, DBS is now proposed as an efficient tool to diagnose HAE with C1 inhibitor deficiency, and its use would improve the access to outbound areas and family members. Regarding HAE with normal C1 inhibitor, complement assays' results are normal and the genetic sequencing of target genes, such as exon 9 of and , is the only available method. New methods to measure cleaved high-molecular-weight kininogen and activated plasma kallikrein have emerged as potential biochemical tests to identify bradykinin-mediated angioedema. Validated biomarkers of kallikrein-kinin system activation could be helpful in differentiating mechanisms of angioedema. Our aim is to focus on the capability to differentiate histaminergic AE from bradykinin-mediated AE. In addition, we will describe the challenges developing specific tests like direct bradykinin measurements. The need for quality tests to improve the diagnosis is well represented by the variability of results in functional assays.
Topics: Angioedema; Angioedemas, Hereditary; Biomarkers; Bradykinin; Complement C1 Inhibitor Protein; DNA Mutational Analysis; Diagnosis, Differential; Diagnostic Errors; Dried Blood Spot Testing; Enzyme-Linked Immunosorbent Assay; Factor XII; Humans; Mutation; Plasminogen; Recurrence
PubMed: 34956216
DOI: 10.3389/fimmu.2021.785736 -
Frontiers in Allergy 2022Hereditary angioedema (HAE) is a rare disease caused by mutations in the gene. This results in deficient or dysfunctional C1 esterase inhibitor (C1-INH) and affects... (Review)
Review
Hereditary angioedema (HAE) is a rare disease caused by mutations in the gene. This results in deficient or dysfunctional C1 esterase inhibitor (C1-INH) and affects multiple proteases involved in the complement, contact-system, coagulation, and fibrinolytic pathways. Current options for the treatment and prevention of HAE attacks include treating all affected pathways direct C1-INH replacement therapy; or specifically targeting components of the contact activation system, in particular by blocking the bradykinin B receptor (B2R) or inhibiting plasma kallikrein, to prevent bradykinin generation. Intravenously administered plasma-derived C1-INH (pdC1-INH) and recombinant human C1-INH have demonstrated efficacy and safety for treatment of HAE attacks, although time to onset of symptom relief varied among trials, specific agents, and dosing regimens. Data from retrospective and observational analyses support that short-term prophylaxis with intravenous C1-INH products can help prevent HAE attacks in patients undergoing medical or dental procedures. Long-term prophylaxis with intravenous or subcutaneous pdC1-INH significantly decreased the HAE attack rate vs. placebo, although breakthrough attacks were observed. Pathway-specific therapies for the management of HAE include the B2R antagonist icatibant and plasma kallikrein inhibitors ecallantide, lanadelumab, and berotralstat. Icatibant, administered for treatment of angioedema attacks, reduced B2R-mediated vascular permeability and, compared with placebo, reduced the time to initial symptom improvement. Plasma kallikrein inhibitors, such as ecallantide, block the binding site of kallikrein to prevent cleavage of high molecular weight kininogen and subsequent bradykinin generation. Ecallantide was shown to be efficacious for HAE attacks and is licensed for this indication in the United States, but the labeling recommends that only health care providers administer treatment because of the risk of anaphylaxis. In addition to C1-INH replacement therapy, the plasma kallikrein inhibitors lanadelumab and berotralstat are recommended as first-line options for long-term prophylaxis and have demonstrated marked reductions in HAE attack rates. Investigational therapies, including the activated factor XII inhibitor garadacimab and an antisense oligonucleotide targeting plasma prekallikrein messenger RNA (donidalorsen), have shown promise as long-term prophylaxis. Given the requirement of lifelong management for HAE, further research is needed to determine how best to individualize optimal treatments for each patient.
PubMed: 36172291
DOI: 10.3389/falgy.2022.952233 -
Frontiers in Physiology 2023Human plasma kallikrein (PKa) is obtained by activating its precursor, prekallikrein (PK), historically named the Fletcher factor. Human PKa and tissue kallikreins are... (Review)
Review
Human plasma kallikrein (PKa) is obtained by activating its precursor, prekallikrein (PK), historically named the Fletcher factor. Human PKa and tissue kallikreins are serine proteases from the same family, having high- and low-molecular weight kininogens (HKs and LKs) as substrates, releasing bradykinin (Bk) and Lys-bradykinin (Lys-Bk), respectively. This review presents a brief history of human PKa with details and recent observations of its evolution among the vertebrate coagulation proteins, including the relations with Factor XI. We explored the role of Factor XII in activating the plasma kallikrein-kinin system (KKS), the mechanism of activity and control in the KKS, and the function of HK on contact activation proteins on cell membranes. The role of human PKa in cell biology regarding the contact system and KSS, particularly the endothelial cells, and neutrophils, in inflammatory processes and infectious diseases, was also approached. We examined the natural plasma protein inhibitors, including a detailed survey of human PKa inhibitors' development and their potential market.
PubMed: 37711466
DOI: 10.3389/fphys.2023.1188816 -
Frontiers in Cardiovascular Medicine 2022The contact system consists of coagulation factor XII (FXII), prekallikrein, and H-kininogen (HK) and plays important roles in many diseases. Plasma kallikrein (PKa)...
OBJECTIVES
The contact system consists of coagulation factor XII (FXII), prekallikrein, and H-kininogen (HK) and plays important roles in many diseases. Plasma kallikrein (PKa) cleaved HK (cHK) is a marker of contact activation. Presently, we developed a specific and precise enzyme-linked immunosorbent assay (ELISA) for determination of cHK and
METHODS
Cleaved HK specific mouse monoclonal antibodies (mAbs) were generated using a peptide corresponding to the PKa cleavage site on HK as immunogen. ELISA, surface plasmon resonance analysis, and immunoprecipitation established the specificity of the antibody, which subsequently was used in a sandwich ELISA. The analytical imprecision and the concentration of cHK in a reference population and in women receiving oral contraceptives (OC) were determined. cHK was assessed in plasma exposed to polytetrafluoroethylene, silicone, and glass tubes.
RESULTS
The selected mAb showed excellent specificity towards cHK. The intra-assay and inter-assay CV of the ELISA were 3.6 and 6.0%, respectively. The reference population (60 women, 60 men) displayed a median cHK plasma concentration of 1.38 μg/mL and a reference interval of 0.82 - 2.56 μg/mL. Women receiving OC had significantly higher concentrations, < 0.001. cHK was significantly elevated in plasma exposed to polytetrafluoroethylene, = 0.001, and glass, < 0.0001.
CONCLUSION
The ELISA showed excellent precision and specificity. cHK assessment demonstrated ongoing contact activation in healthy individuals, augmented by OC. The cHK antibody and the ELISA could be promising tools in contact activation related diseases and investigations of the plasma compatibility of blood contacting biomaterials.
PubMed: 35669477
DOI: 10.3389/fcvm.2022.873975 -
Biological Chemistry Mar 2013Diabetic retinopathy (DR) occurs, to some extent, in most people with at least 20 years' duration of diabetes mellitus. The progression of DR to its sight-threatening... (Review)
Review
Diabetic retinopathy (DR) occurs, to some extent, in most people with at least 20 years' duration of diabetes mellitus. The progression of DR to its sight-threatening stages is usually associated with the worsening of underlying retinal vascular dysfunction and disease. The plasma kallikrein-kinin system (KKS) is activated during vascular injury, where it mediates important functions in innate inflammation, blood flow, and coagulation. Recent findings from human vitreous proteomics and experimental studies on diabetic animal models have implicated the KKS in contributing to DR. Vitreous fluid from people with advanced stages of DR contains increased levels of plasma KKS components, including plasma kallikrein (PK), coagulation factor XII, and high-molecular-weight kininogen. Both bradykinin B1 and B2 receptor isoforms (B1R and B2R, respectively) are expressed in human retina, and retinal B1R levels are increased in diabetic rodents. The activation of the intraocular KKS induces retinal vascular permeability, vasodilation, and retinal thickening, and these responses are exacerbated in diabetic rats. Preclinical studies have shown that the administration of PK inhibitors and B1R antagonists to diabetic rats ameliorates retinal vascular hyperpermeability and inflammation. These findings suggest that components of plasma KKS are potential therapeutic targets for diabetic macular edema.
Topics: Blood Chemical Analysis; Diabetic Retinopathy; Humans; Kallikrein-Kinin System; Plasma; Retinal Neovascularization
PubMed: 23362193
DOI: 10.1515/hsz-2012-0316