Metabolite biomarkers for diseases associated with contact activation system
Metabolite biomarkers for HAE, measured via mass spectrometry and immunoassays, address the challenge of misdiagnosis by providing precise diagnostic tools for hereditary angioedema, enhancing treatment efficacy and patient safety.
Patent Information
- Application Number
- JP2025092519
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2017-06-12
- Filing Date
- 2025-06-03
- Publication Date
- 2025-08-26
AI Technical Summary
Current diagnostic methods for hereditary angioedema (HAE) are inadequate, often misdiagnosing the condition as an allergy and failing to provide early detection, leading to ineffective treatments and potential life-threatening emergencies.
Identification of metabolite biomarkers differentially present in biological samples from HAE patients compared to healthy individuals, using mass spectrometry and immunoassays to measure levels of specific metabolites such as serotonin, fatty acid amides, lipid peroxides, and steroid metabolites, allowing for accurate diagnosis and treatment monitoring.
Enables early and accurate identification of HAE, facilitating timely intervention and personalized treatment strategies, reducing the risk of severe attacks and improving patient management.
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Figure 2025124816000001_ABST
Abstract
Description
[Technical Field]
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 62 / 518,367, filed June 12, 2017, and U.S. Provisional Application No. 62 / 395,770, filed September 16, 2016. The entire contents of each of these referenced applications are incorporated herein by reference. [Background technology]
[0002] background The plasma contact activation system (CPAS) is a pro-inflammatory and pro-coagulant system involving a group of plasma proteases. It is activated by factor XIIa upon exposure to foreign or negatively charged surfaces or by prolylcarboxypeptidase on the surface of endothelial cells (Sainz IM et al., Thromb. Haemost. (2007) 98, 77-83). Inappropriate or unregulated activation of the contact system is involved in various diseases, including hereditary angioedema (HAE).
[0003] HAE is a disease that causes sudden attacks of swelling that can affect multiple parts of the body (such as the face, limbs, genitals, gastrointestinal tract, and upper respiratory tract). Because HAE symptoms often resemble those of allergies or intestinal colic, patients with HAE are often difficult to identify until they exhibit severe or life-threatening symptoms. Early diagnosis would allow for better management of emergency situations involving acute HAE attacks, and early diagnosis would also help manage HAE patients to prevent or attenuate acute HAE episodes (e.g., by having HAE patients avoid exposure to stimuli that may trigger HAE episodes).
[0004] Therefore, it is of great interest to identify biomarkers for HAE and develop reliable diagnostic and prognostic methods to identify subjects with specific types of HAE or at risk of suffering from acute HAE attacks. Such biomarkers would also be beneficial for research into the mechanisms of the disease, which may facilitate the development of effective new treatments for this disease. Summary of the Invention
[0005] Summary of the Disclosure The present disclosure is based on the identification of metabolite biomarkers that are differentially present in biological samples obtained from subjects with diseases associated with the contact activation system compared to healthy individuals, or that are differentially present in biological samples obtained from subjects at different stages of such diseases (e.g., seizures versus quiescence).
[0006] Accordingly, one aspect of the present disclosure provides a method of analyzing a sample, comprising: (i) providing a biological sample (e.g., a serum or plasma sample) obtained from a subject (e.g., a human subject) having, suspected of having, or at risk for a disease associated with the contact activation system; and (ii) measuring the level of a set of metabolic biomarkers comprising at least one metabolic biomarker selected from Table 1. In some embodiments, the disease associated with the contact activation system is hereditary angioedema (HAE), such as HAE type I or HAE type II. In some examples, the set of biomarkers consists of between 2 and 10 metabolic biomarkers selected from Table 1.
[0007] In any of the methods described herein, at least one metabolite is serotonin or a metabolite related to serotonin metabolism.In some embodiments, at least one metabolite biomarker is a metabolite related to fatty acid amide hydrolase activity (e.g., a fatty acid amide such as palmitic acid amide, oleic acid amide or linoleic acid amide).In some embodiments, at least one metabolite biomarker is lipid peroxide (e.g., 9-hydroxyoctadecadienoic acid (9-HODE), 13-hydroxyoctadecadienoic acid (13-HODE), 9,10-dihydroxy-12Z-octadecenoic acid (9,10-DiHOME), 12,13-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME), or 19,20-dihydroxy-4Z,7Z,10Z,13Z,16Z-docosapentaenoic acid (19,20-DiHDPA)). In some embodiments, the at least one metabolite biomarker is a metabolite involved in sulfur metabolism (eg, N-acetylmethionine, methionine sulfone, S-adenosylhomocysteine, cystine, or cysteine sulfinic acid).In some embodiments, the at least one metabolite biomarker is a metabolite involved in steroid metabolism (e.g., pregnenolone sulfate, 5α-pregnane-3β,20β-diol monosulfate, pregnene-diol disulfate, pregn steroid monosulfate, prenanediol-3-glucuronide, cortisol, corticosterone, cortisone, dehydroisoandrosterone sulfate (DHEA-S), 16α-hydroxyDHEA 3-sulfate, epiandrosterone sulfate, androsterone sulfate, 4-androstene-3β,17β-diol monosulfate, 4-androstene-3α,17α-diol monosulfate, 4-androstene-3β,17β-diol disulfate, 5α-androstane-3α,17α-diol monosulfate, 5α-androstane-3β,17β-diol disulfate, androsteroid monosulfate, etiocholanolong glucuronide, or pregnanolone / alloprenanolone sulfate. In some embodiments, the at least one metabolic biomarker is a fatty acid (e.g., eicosapentaenoic acid (EPA), mead acid, or stearidonic acid). In some embodiments, at least one metabolic biomarker is a precursor to a cofactor (eg, a precursor to a cofactor of coenzyme A, such as nicotinamide or pantothenic acid).
[0008] In some embodiments, measuring the levels of the set of biomarkers involves mass spectrometry, chromatography, or immunoassay. In some embodiments, measuring the levels of the set of biomarkers involves mass spectrometry, where the biological sample is subjected to a separation step (e.g., gas chromatography, liquid chromatography, or capillary electrophoresis) prior to mass spectrometry.
[0009] In some embodiments, the method further comprises: if the level of the set of biomarkers in the subject deviates from the level of the same set of biomarkers in a control subject, identifying the subject as having a disease associated with the contact system. In some embodiments, the method further comprises: if the subject is identified as having a disease, administering to the subject an effective amount of a therapeutic agent for treating the disease (such as a plasma kallikrein (pKal) inhibitor, a bradykinin 2 receptor inhibitor, and / or a C1 esterase inhibitor). In some embodiments, the pKal inhibitor is an anti-pKal antibody. In some embodiments, the therapeutic agent is lanadelumab, ecallantide, icatibant, or human plasma-derived C1 esterase inhibitor.
[0010] In some embodiments, the subject is a human patient undergoing treatment for a disease, wherein the method further comprises assessing the efficacy of the treatment based on the levels of the set of metabolic biomarkers, wherein a deviation in the subject's levels of the set of metabolic biomarkers from those of a control subject indicates the efficacy of the treatment. In some embodiments, the method further comprises identifying a treatment suitable for the subject based on the levels of the set of metabolic biomarkers. In some embodiments, the method further comprises identifying the subject as a candidate for treatment for the disease based on the levels of the set of metabolic biomarkers.
[0011] In some embodiments, the human patient has a history of a disease (e.g., HAE). In some embodiments, the set of metabolite biomarkers includes one or more metabolite biomarkers selected from the list consisting of corticosterone, eicosapentaenoic acid, mead acid, stearidonic acid, nicotinamide, and pantothenic acid. In some embodiments, the method further includes assessing the risk of a disease attack (e.g., an HAE attack) based on the level of the set of metabolite biomarkers, and deviation of the level of the set of metabolite biomarkers from that of a control subject indicates a risk of a disease attack. In some embodiments, the method further includes administering a therapeutic agent to the subject if the subject is identified as being at risk of a disease attack.
[0012] The present disclosure provides biomarkers that can identify patients with diseases associated with the contact activation system (e.g., HAE). Measuring the levels of a set of biomarkers can also be useful in the assessment and treatment of such diseases.
[0013] Another aspect of the present disclosure provides a method for identifying a subject as having or at risk of having a disease associated with the contact activation system, the method comprising: (i) providing a biological sample obtained from the subject; (ii) measuring levels of a set of metabolite biomarkers; and (iii) identifying the subject as having or at risk of having the disease if the levels of the set of metabolite biomarkers deviate from the levels of the set of metabolite biomarkers in a control sample.
[0014] Another aspect provides a method for assessing the risk of an attack of a disease associated with activation of the contact system (e.g., an HAE attack), comprising: (i) providing a biological sample from a subject; (ii) measuring the levels of a set of metabolic biomarkers; and (iii) identifying the subject as being at risk of having an attack of the disease if the levels of the set of metabolic biomarkers deviate from the levels of the set of metabolic biomarkers in a control sample.
[0015] In another aspect, a kit for analyzing a sample from a subject having, suspected of having, or at risk for having a disease associated with the contact system is provided, the kit comprising a first binding substance specific for a first metabolic marker selected from Table 1 and a second binding substance specific for a second metabolic marker selected from Table 1, wherein the first metabolic marker and the second metabolic marker are different. In some embodiments, the kit further comprises at least one additional binding substance for another metabolic marker selected from Table 1. In some examples, the first binding substance is an antibody specific for the first metabolic biomarker, and / or the second binding substance is an antibody specific for the second metabolic biomarker. In some embodiments, the kit may further comprise a first detection substance that binds to the first binding substance and a second detection substance that binds to the second binding substance. In some embodiments, the first binding substance and the second binding substance may be immobilized on a support member.
[0016] The details of one or more embodiments of the present disclosure are set forth in the description below. Other features or advantages of the present disclosure will be apparent from the following drawings and detailed description of certain embodiments, as well as from the appended claims.
[0017] The following drawings form part of the present specification and are included to further demonstrate certain aspects of the disclosure that can be better understood by reference to one or more of these drawings in combination with the detailed description of specific embodiments presented herein. [Brief explanation of the drawings]
[0018] [Figure 1-1]Figure 1 presents graphs showing the results of metabolite analysis from control healthy subjects and patients with HAE either during an attack or at baseline by random forest analysis. A: Random forest analysis separated patients with basal HAE from healthy individuals with 77.5% accuracy. B: Patients with basal HAE from patients with HAE during an attack with 20% accuracy. [Figure 1-2] Same as above. [Figure 2] Figure 2 presents graphs showing the levels of serotonin detected in plasma samples from patients with HAE (type I / II) and healthy volunteers. A: Diagram showing the levels of serotonin detected in plasma samples from patients with HAE (type I / II; n=20) compared to healthy volunteers (n=20). B: Diagram showing the levels of serotonin detected in plasma samples from basal HAE patients (n=20) grouped based on their history of HAE attacks (<1 per month, 1-2 per month, or >2 per month). Serotonin levels are presented as fold increase relative to the levels in healthy volunteers (n=20). DETAILED DESCRIPTION OF THE INVENTION
[0019] Detailed Description The contact activation system initiates the intrinsic pathway of blood coagulation and promotes inflammation through the release of the pro-inflammatory peptide bradykinin. Factor XII (FXII), also known as Hageman factor, is a serine protease that plays a role in activating the intrinsic pathway of blood coagulation and the kallikrein-kinin system. FXII is activated by negatively charged surfaces (e.g., polyanionic surfaces, glass, polyphosphate, ellagic acid) to produce its active form, FXIIa. Activated FXIIa has the ability to cleave prekallikrein, generating activated pKal. Activated pKal can then cleave FXII to FXIIa, which in turn generates more pKal, which further activates FXII to FXIIa, creating a positive feedback loop. Activated pKal can also cleave high-molecular-weight kininogen (HMWK) to release bradykinin. In diseases associated with activation of the contact system, such as HAE, increased levels of bradykinin can induce vasodilation and inflammation, leading to edematous HAE attacks. It is desirable to identify novel biomarkers that can be used to identify diseases, such as those mediated by the contact activation system, and to identify subjects who have or are at risk for having such diseases.
[0020] The present disclosure is based, at least in part, on the identification, by metabolome analysis, of metabolites that are differentially present in biological samples obtained from subjects with a disease associated with the contact activation system (e.g., basal state or seizures) compared to healthy individuals. It was unexpectedly observed that metabolites belonging to specific cellular pathways or processes (e.g., metabolites involved in sulfur metabolism, steroid metabolism, serotonin metabolism, metabolites associated with fatty acid amide hydrolase activity) and metabolite families (e.g., fatty acids) have similar trends (e.g., elevated or decreased levels) in samples from subjects with disease compared to healthy individuals. Furthermore, some metabolites were identified as differentially present in biological samples obtained from subjects with a disease of the contact activation system during a seizure compared to subjects with the disease in a quiescent (basal) state.
[0021] Thus, provided herein are methods for analyzing biological samples from subjects having, suspected of having, or at risk for a disease associated with the contact activation system (e.g., HAE) by detecting the presence or measuring the levels of a set of metabolite biomarkers. Such methods may be useful, for example, to identify patients at risk for a disease associated with the contact activation system (e.g., HAE), to select candidates for treatment, to monitor disease progression or condition, to evaluate the effectiveness of treatment for the disease, to determine a course of treatment, to assess whether a subject is at risk for developing the disease, to identify whether a disease or disorder is associated with the contact activation system, and / or for research purposes (including, for example, studying disease mechanisms and / or biological pathways / processes involved in the disease, which may be utilized for the development of new therapies).
[0022] Metabolite biomarkers of the contact activation system The methods and kits described herein are based, at least in part, on the identification of metabolites found to be differentially present in samples from subjects with HAE compared to samples from healthy subjects, and / or to be differentially present in samples at different stages of such disease (e.g., basal state vs. attack). As used herein, the term "metabolite biomarker" or "set of metabolite biomarkers" refers to a metabolite or set of metabolites that are present at different levels in samples from different groups of subjects (e.g., subjects with a disease associated with the contact system vs. healthy subjects (e.g., subjects without the disease), or subjects with a disease but in a quiescent stage vs. subjects undergoing an attack of the disease). Such biomarkers / sets of biomarkers may be used in both diagnostic / prognostic applications and non-clinical applications (e.g., for research purposes).
[0023] In some embodiments, a metabolite biomarker may be present at an elevated level in a sample from a subject with a disease associated with the contact activation system (e.g., HAE) compared to the level of the same metabolite biomarker in a sample from a healthy subject. In some embodiments, a metabolite biomarker may be present at a decreased level in a sample from a subject with a disease associated with the contact activation system (e.g., HAE) compared to the level of the biomarker in a sample from a healthy subject. In yet another example, a metabolite biomarker may be present at an elevated level in a sample obtained from a subject during an attack of a disease as described herein compared to a subject during a quiescent state of the disease. Alternatively, a metabolite biomarker may be present at a decreased level in a sample obtained from a subject during an attack of a disease as described herein compared to a subject during a quiescent state of the disease.
[0024] In some embodiments, a set of metabolic biomarkers comprising one or more biomarkers may be analyzed using the methods described herein. When a set of metabolic biomarkers comprises two or more biomarkers, all of the biomarkers may be present at elevated or decreased levels in diseased subjects compared to healthy subjects. Alternatively, the set of metabolic biomarkers may include at least one biomarker that is elevated in diseased subjects compared to healthy subjects and at least one biomarker that is decreased in diseased subjects compared to healthy subjects.
[0025] Similarly, a set of metabolic biomarkers for distinguishing between subjects undergoing a disease attack and subjects in a quiescent state of the disease, the set of biomarkers may include multiple biomarkers all of which are elevated or decreased in a first disease stage (e.g., a stroke) relative to a second disease stage (e.g., a quiescent state), or the set of biomarkers may include at least one biomarker that is elevated in the first disease stage relative to the second disease stage and at least one biomarker that is decreased in the first disease stage relative to the second disease stage.
[0026] Table 1 below provides metabolite biomarkers that can be assessed by the methods described herein to assess a subject or a biological sample from a subject for diseases associated with the contact activation system.
[0027] [Table 1] TIFF2025124816000003.tif55162
[0028] In some embodiments, the set of biomarkers measured and analyzed in any of the methods described herein includes at least one (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) metabolites selected from Table 1.
[0029] As described in Example 1, it was unexpectedly found that several metabolites involved in different cellular processes and pathways are differentially present in samples from subjects with HAE compared to healthy subjects. This data indicates that the metabolites or metabolic pathways shown in Table 1 may play a role in or be affected by diseases associated with the contact system.
[0030] The metabolite biomarkers described herein may be characterized as "involved in" or "associated with" a particular pathway or activity. As used herein, the terms "involved in" or "associated with" apply to metabolites that contribute to a pathway. For example, a metabolite involved in or associated with a pathway may perform a function within the pathway, may be a precursor to another molecule within the pathway, a substrate for an enzyme within the pathway, or may be a product of the pathway (including a by-product or degradation product or molecule). In some embodiments, the pathway is a metabolic pathway, such as a biosynthetic pathway or a catabolic pathway. In some embodiments, a metabolite may be described as associated with the activity of a particular enzyme. For example, a metabolite associated with the activity of an enzyme may be a substrate for that enzyme, a product of the activity of that enzyme, or a cofactor whose presence regulates or promotes the activity of that enzyme. In some embodiments, the level of an enzyme's substrate or enzyme's product is indicative of the level of that enzyme's activity (e.g., during a disease or during a particular state of a disease).
[0031] As used herein, the term "precursor," such as a precursor of a cofactor, refers to a metabolite that precedes another molecule (e.g., a product) in a synthetic pathway. For example, a precursor of a cofactor is a metabolite in the synthetic pathway of the cofactor that can be modified or used to produce the cofactor. Also as used herein, the term "cofactor" refers to a molecule that interacts with an enzyme to promote the activity of the enzyme.
[0032] In some embodiments, the set of biomarkers includes serotonin or one or more metabolites involved in serotonin production (eg, one or more metabolites involved in serotonin production selected from Table 1).
[0033] In some embodiments, the set of biomarkers includes one or more metabolites associated with fatty acid amide hydrolase activity (e.g., one or more metabolites involved in serotonin production selected from Table 1). A metabolite associated with fatty acid amide hydrolase activity can be any metabolite involved in a reaction catalyzed by fatty acid amide hydrolase. Such a metabolite can be a substrate of the enzyme, a product of the enzyme, or any intermediate thereof.
[0034] In some embodiments, the set of biomarkers includes one or more metabolites that are lipid peroxides, which refer to any product of the reaction of lipid peroxidation. Examples include the lipid peroxide compounds listed in Table 1. In some embodiments, the set of biomarkers includes one or more metabolites associated with sulfur metabolism (e.g., one or more metabolites involved in sulfur metabolism selected from Table 1).
[0035] In some embodiments, the set of biomarkers includes one or more metabolites associated with steroid metabolism (eg, one or more metabolites involved in steroid metabolism selected from Table 1).
[0036] As also described in Example 1, several metabolites have also been found to be differentially present in samples from subjects with HAE during an HAE attack compared to subjects with HAE during a resting (basal) state. In some embodiments, the set of biomarkers includes one or more metabolites that are fatty acids (e.g., one or more metabolites that are fatty acids selected from Table 1). In some embodiments, the set of biomarkers includes one or more metabolites that are precursors to cofactors (e.g., one or more metabolites that are precursors to cofactors selected from Table 1). In some embodiments, the set of biomarkers includes corticosterone.
[0037] The utility of metabolic biomarkers One aspect of the present disclosure relates to a method for analyzing a sample obtained from a subject (e.g., a human patient) having, suspected of having, or at risk for a disease associated with the contact activation system by measuring the levels of a set of biomarkers as described herein in the sample. Results obtained from such assays may be useful for diagnostic and / or prognostic applications, as well as other non-clinical applications (such as research applications).
[0038] (i) Analysis of biological samples The methods described herein involve providing a biological sample obtained from a subject. As used herein, "biological sample" refers to a composition containing tissue (e.g., blood, plasma, or protein) from a subject. A sample includes both the initial, unprocessed sample collected from a subject as well as subsequently processed (e.g., partially purified or preserved) forms. Exemplary samples include blood, plasma, tears, or mucus. In some embodiments, the sample is a bodily fluid sample, such as a serum sample or plasma sample. In some embodiments, multiple (e.g., at least two, three, four, five, or more) biological samples may be collected from a subject over time or at specific time intervals, for example, to assess disease progression or the effectiveness of a treatment.
[0039] A biological sample can be obtained from a subject using any means known in the art. In some embodiments, a sample is obtained from a subject by collecting a sample (e.g., a blood sample) in an evacuated collection tube (e.g., a vacuum collection tube). In some embodiments, the evacuated collection tube contains one or more protease inhibitors, for example, to reduce or prevent activation of the ex vivo contact system during sample collection. Such protease inhibitors may be included in a liquid formulation. In some embodiments, the protease inhibitors include at least one serine protease inhibitor and at least one cysteine protease inhibitor. Such evacuated collection tubes are known in the art. See, for example, PCT Application No. US2016 / 046681. Optionally, the evacuated collection tube may further contain one or more anticoagulants.
[0040] The terms "patient," "subject," or "individual" may be used interchangeably and refer to a subject in need of analysis as described herein. In some embodiments, the subject is a human or a non-human mammal. In some embodiments, the subject is suspected of or at risk for a disease or disorder associated with the contact activation system (e.g., HAE). Such a subject may exhibit one or more symptoms associated with the disease. Alternatively, or in addition, such a subject may possess one or more risk factors for the disease (e.g., a genetic factor associated with the disease (e.g., a genetic defect in CI-INH)).
[0041] Alternatively, the subject who needs the analysis described herein may be a patient with the disease. Such a subject may currently be suffering from an attack of the disease, or may have previously suffered from the disease (e.g., currently in a quiescent state). In some cases, the subject is a human patient who may be undergoing treatment for the disease (e.g., treatment with C1 esterase inhibitor (C1-INH), plasma kallikrein inhibitor, or bradykinin inhibitor). In other cases, such a human patient may not be undergoing such treatment.
[0042] Examples of diseases associated with the contact activation system include, but are not limited to, kallikrein-mediated disorders, e.g., bradykinin-mediated disorders (such as hereditary angioedema (HAE)), non-histamine-dependent idiopathic angioedema, rheumatoid arthritis, Crohn's disease, lupus, Alzheimer's disease, septic shock, burns, cerebral ischemia / reperfusion injury, cerebral edema, diabetic retinopathy, diabetic nephropathy, macular edema, vasculitis, arterial or venous thrombosis, thrombosis associated with ventricular assist devices or stents, heparin-induced thrombocytopenia with thrombosis, thromboembolic disease, and coronary heart disease with unstable angina, edema, eye disease, gout, intestinal bowel disease, and the like. disease), oral mucositis, neuropathic pain, inflammatory pain, spinal stenosis - degenerative spinal disease, postoperative ileus, aortic aneurysm, osteoarthritis, hereditary angioedema, pulmonary embolism, stroke, head trauma or peritumoral cerebral edema, sepsis, acute middle cerebral artery (MCA) ischemic event (stroke), restenosis (e.g., after angioplasty), systemic lupus erythematosus nephritis, autoimmune diseases, inflammatory diseases, cardiovascular diseases, neurological diseases, diseases associated with protein misfolding, diseases associated with angiogenesis, hypertensive and diabetic nephropathy, allergic and respiratory diseases (e.g., anaphylaxis, asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, cystic fibrosis, persistent rhinitis), and tissue injury (e.g., burns or chemical injuries).
[0043] In some embodiments, the disease or condition associated with the contact activation system is hereditary angioedema (HAE).Hereditary angioedema (HAE) is also known as "Quincke's edema," C1 esterase inhibitor deficiency, C1 inhibitor deficiency, and hereditary angioneurotic edema (HANE).HAE is characterized by recurrent episodes of severe swelling (angioedema), which can affect, for example, the extremities, face, genitals, gastrointestinal tract, and airway.Symptoms of HAE include, for example, swelling in the arms, legs, lips, eyes, tongue, and / or throat; airway obstruction, which may be accompanied by throat swelling and sudden hoarseness; repeated episodes of abdominal cramps without apparent cause; and / or intestinal swelling, which may become severe and lead to abdominal cramps, vomiting, dehydration, diarrhea, pain, and / or shock.Approximately one-third of individuals with HAE develop a non-itchy rash called erythema marginatum during an attack.
[0044] Airway swelling can be life-threatening and, in some patients, leads to death. The mortality rate is estimated at 15–33%. HAE results in approximately 15,000–30,000 emergency room visits per year. Trauma or stress (e.g., dental procedures, illness (e.g., viral illnesses such as colds and influenza), menstruation, and surgery) can trigger attacks of angioedema. To prevent acute attacks of HAE, patients can try to avoid specific stimuli that have previously triggered attacks. However, attacks often occur without a known trigger. Typically, HAE symptoms first appear in childhood and worsen during adolescence. On average, untreated individuals experience attacks every 1–2 weeks, with most episodes lasting approximately 3–4 days (ghr.nlm.nih.gov / condition / hereditary-angioedema). The frequency and duration of attacks vary widely among people with hereditary angioedema, even within the same family.
[0045] There are three types of HAE, known as types I, II, and III. It is estimated that 1 in 50,000 people suffer from HAE, with type I accounting for approximately 85% of cases, type II accounting for approximately 15% of cases, and type III being extremely rare. Type III is the most recently described form and was initially thought to occur only in women, although families with affected men have been identified.
[0046] HAE is inherited in an autosomal dominant pattern, so affected individuals may inherit the mutation from one affected parent. De novo mutations in the gene can also occur, so HAE can occur in people with no family history of the disorder. It is estimated that 20-25% of cases arise from de novo spontaneous mutations.
[0047] Mutations in the SERPING1 gene cause type I and type II hereditary angioedema. The SERPING1 gene provides instructions for producing the C1 inhibitor protein, which is important for suppressing inflammation. C1 inhibitor blocks the activity of certain proteins that promote inflammation. Mutations that cause type I hereditary angioedema reduce levels of C1 inhibitor in the blood. In contrast, mutations that cause type II hereditary angioedema result in the production of abnormally functioning C1 inhibitor. When functional C1 inhibitor levels are inadequate, excessive amounts of bradykinin are produced. Bradykinin promotes inflammation by increasing fluid leakage through blood vessel walls into body tissues. Excessive accumulation of fluid in body tissues causes the swelling episodes seen in individuals with type I and type II hereditary angioedema.
[0048] Mutations in the F12 gene are associated with some cases of type III hereditary angioedema. The F12 gene provides instructions for producing clotting factor XII. In addition to playing a critical role in blood clotting (clotting), factor XII is also an important stimulator of inflammation and is involved in the production of bradykinin. Specific mutations in the F12 gene result in the production of increased activity of factor XII. As a result, more bradykinin is produced, increasing the leakiness of blood vessel walls, which leads to episodes of swelling. The cause of other cases of type III hereditary angioedema remains unknown. In these cases, mutations in one or more yet-to-be-identified genes may be responsible for the disorder.
[0049] Although HAE can manifest similarly to other forms of angioedema caused by allergies or other medical conditions, HAE differs significantly in terms of cause and treatment. When HAE is misdiagnosed as an allergy, it is most commonly treated with antihistamines, steroids, and / or epinephrine, which are usually ineffective for HAE (although epinephrine can be used for life-threatening reactions). Misdiagnosis has also led to unnecessary exploratory laparotomy in patients with abdominal swelling, and in some HAE patients, abdominal pain has been incorrectly diagnosed as being psychogenic.
[0050] C1 inhibitor therapy as well as other therapies for HAE are described in Kaplan, AP, J Allergy Clin Immunol, 2010, 126(5):918-925.
[0051] Acute treatment of an HAE attack is administered to halt the progression of edema as quickly as possible. Intravenously administered C1 inhibitor concentrates derived from donor blood are one type of acute treatment. However, this treatment is not available in many countries. In emergency situations where C1 inhibitor concentrates are unavailable, fresh frozen plasma (FFP) can be used as an alternative because it also contains C1 inhibitor.
[0052] Purified C1 inhibitor derived from human blood has been used in Europe since 1979. Several C1 inhibitor treatments are currently available in the United States, and two C1 inhibitor products are currently available in Canada. Verinert (CSL Behring), which is pasteurized, was approved by the FDA in 2009 for acute attacks. Synrise®, which is nanofiltered, was approved by the FDA in 2008 for prophylaxis. Rutin / Ruconest (Pharming) is an investigational recombinant C1 inhibitor that does not carry the risk of infectious disease transmission due to human bloodborne pathogens.
[0053] Treatment for acute HAE attacks may also include medication and / or intravenous fluids for pain relief.
[0054] Other treatments may stimulate C1 inhibitor synthesis or reduce C1 inhibitor consumption. Androgenic drugs such as danazol can reduce the frequency and severity of attacks by stimulating C1 inhibitor production.
[0055] Helicobacter pylori can cause abdominal attacks. Antibiotics to treat H. pylori may reduce abdominal attacks.
[0056] Newer treatments attack the contact cascade. Ecallantide (KALBITOR®) inhibits plasma kallikrein and is approved in the United States. Icatibant (Firasil®, Shire) inhibits the bradykinin B2 receptor and is approved in Europe and the United States.
[0057] Diagnosis of HAE can rely, for example, on family medical history and / or blood tests. Laboratory findings associated with types I, II, and III HAE are described, for example, in Kaplan, AP, J Allergy Clin Immunol, 2010, 126(5):918-925. In type I HAE, C1 inhibitor levels are decreased, as are C4 levels, but C1q levels are normal. In type II HAE, C1 inhibitor levels are normal or increased, but C1 inhibitor function is abnormal. C4 levels are decreased and C1q levels are normal. In type III, C1 inhibitor, C4, and C1q levels may all be normal. The present disclosure is based, at least in part, on the identification of metabolites (Table 1) that have different levels in samples from HAE patients compared to healthy individuals. Measuring the levels of a set of biomarkers of these metabolites can be used to identify whether a subject has a disease (such as HAE). In some embodiments, the methods may be utilized to determine whether a patient has had an HAE attack or is experiencing an HAE attack.
[0058] Symptoms of HAE can be evaluated, for example, by using a questionnaire (for example, a questionnaire that is answered by the patient, clinician, or family). Such questionnaires are known in the art, and include, for example, visual analog scales. For example, see McMillan, CV et al. Patient. 2012;5(2):113-26.
[0059] A biological sample described herein may be subjected to analysis by measuring the level of a set of biomarkers as described herein in the biological sample. The level (e.g., amount) of a biomarker disclosed herein or a change in the level of a biomarker may be assessed using an assay described herein and / or an assay known in the art. One or more of the biomarkers described herein may be analyzed using conventional methods. In some embodiments, the level of a biomarker is assessed or measured by directly detecting a metabolite in the biological sample. Alternatively, or in addition, the level of a metabolite may be assessed or measured indirectly in the biological sample, for example, by detecting the level of a binding agent (e.g., an antibody in an immunoassay) that binds to the metabolite or by detecting the activity of the metabolite.
[0060] The type of detection assay used to detect and / or quantify biomarkers of the contact activation system (such as those presented herein) will depend on the particular context in which the assay will be used (e.g., clinical or research use), the type and number of biomarkers to be detected, and the type and number of patient samples to be run in parallel, to name a few parameters.
[0061] In some embodiments, biomarkers are measured using mass spectrometry. Generally, mass spectrometry relies on separating molecular ions based on the mass-to-charge ratio of the ions. In some embodiments, the mass spectrometry is tandem mass spectrometry, which involves two or more mass analyses. The level of metabolites may be measured by comparing the mass spectrum obtained from mass spectrometry of a sample with the mass spectrum of another sample or a reference or control sample. The identity of the metabolites in the spectrum may be confirmed by comparing the spectrum with a library of spectra or spectra of known metabolites. In some embodiments, before detecting metabolic biomarkers, components of a biological sample may be separated using, for example, chromatographic methods as described herein. Examples of separation methods include, for example, gas chromatography, liquid chromatography, capillary electrophoresis, and ion mobility. In some embodiments, biomarkers are measured using liquid chromatography followed by mass spectrometry.
[0062] In some embodiments, biomarkers are measured using chromatographic methods. Chromatography allows for the separation of molecules (in a mobile phase) based on the migration of molecules through a medium (solid phase). Examples of chromatographic methods that can be compatible with the methods described herein include, but are not limited to, gas chromatography, liquid chromatography, reversed-phase chromatography, ion-exchange chromatography, size-exclusion chromatography, and affinity chromatography.
[0063] In some embodiments, biomarkers are measured using immunoassays. Examples of immunoassays include, but are not limited to, immunoblotting assays (Western blots), enzyme-linked immunosorbent assays (ELISAs) (e.g., sandwich ELISAs), radioimmunoassays, electrochemiluminescence-based detection assays, magnetic immunoassays, lateral flow assays, and related techniques. Further suitable immunoassays for detecting the biomarkers presented herein will be apparent to those skilled in the art. However, it will be apparent to those skilled in the art that the present disclosure is not limited to immunoassays, and that detection assays that rely on chromogenic substrates may also be useful for detecting and / or quantifying contact-based biomarkers as presented herein.
[0064] ELISAs are known in the art (see, e.g., Crowther, John R (2009), "The ELISA Guidebook," 2nd ed., Humana Press and Lequin R (2005), "Enzyme immunoassay (EIA) / enzyme-linked immunosorbent assay (ELISA)," Clin. Chem. 51(12):2415-8), and exemplary ELISAs are described herein. Kits for performing ELISAs are also known in the art and commercially available (see, e.g., ELISA kits from Life Technologies and BD Biosciences).
[0065] In some embodiments, immunoassays are used to measure the level of metabolic biomarker(s). The immunoassays described herein may be in a sandwich ELISA format, in which a first binding substance that specifically binds to a metabolite of a set of biomarkers is immobilized on a support member. The support member may then be incubated with a biological sample as described herein for a suitable time under conditions that allow the formation of a complex between the binding substance and a metabolite in the sample. Such a complex may then be detected using a detection substance that binds to the metabolite, the binding substance-metabolite complex, or the binding substance. The detection substance may be conjugated to a label that can directly or indirectly emit a signal. The intensity of the signal represents the level of the metabolite in the sample. In some embodiments, the detection substance is detected, and its level represents the level of the metabolite in the sample.
[0066] Any binding substance that specifically binds to a desired metabolite may be used in the methods and kits described herein to measure the level of a metabolite in a biological sample. In some embodiments, the binding substance is an antibody that specifically binds to a desired metabolite. In some embodiments, the binding substance is an aptamer antibody that specifically binds to a desired metabolite. In some embodiments, a sample may be contacted simultaneously or sequentially with two or more binding substances that bind to different metabolites (e.g., multiplex analysis; e.g., SOMAScan™ assay (SOMALogic)). The biological sample is contacted with the binding substance under appropriate conditions. In general, the term "contacting" refers to bringing the binding substance into contact with the biological sample or agent for a suitable time sufficient to form a complex between the binding substance and the metabolite (if present) in the sample. In some embodiments, contacting is performed by capillary action, in which the biological sample or agent crosses the surface of a support membrane.
[0067] In some embodiments, immunoassays may be performed on low-throughput platforms, including simple immunoassay formats. For example, low-throughput platforms may be used to measure the presence and amount of metabolites in biological samples (e.g., biological tissues, tissue extracts) for diagnostic methods, for monitoring disease and / or treatment progression, and / or for predicting whether a disease or disorder may benefit from a particular treatment.
[0068] In some embodiments, it may be necessary to immobilize the binding substance on a support member. The method for immobilizing the binding substance will depend on factors such as the nature of the binding substance and the material of the support member, and may require a specific buffer. Such methods will be apparent to those skilled in the art. For example, a set of biomarkers in a biological sample as described herein may be measured using any of the kits and / or detection devices also described herein.
[0069] In some embodiments, biomarkers are measured in enzyme-coupled assays. For example, biomarkers present in a biological sample may be used as substrates for an enzymatic reaction that can be coupled to a second reaction. Such a reaction results in the production of a product (e.g., a cofactor) that can be detected, for example, by a change in absorbance or fluorescence.
[0070] As used herein, the terms "measuring" or "measuring" or "detecting" or "detection" mean assessing the presence, absence, quantity or amount (which may be an effective amount) of a substance in a sample (including deriving a qualitative or quantitative concentration level of such a substance), or assessing a value or classification of interest.
[0071] The assay (e.g., Western blot assay) may further involve the use of commercially available quantitative imaging systems (e.g., LICOR imaging technology) (see, e.g., LI-COR Biosciences' Odyssey® CLx Infrared Imaging System). In some embodiments, an electrochemiluminescence detection assay, or an assay relying on a combination of electrochemiluminescence and patterned array technology, is used (e.g., Meso Scale Discovery's (MSD) ECL or MULTI-ARRAY technology assay).
[0072] In any of the methods described herein, the levels of metabolites of the set of biomarkers may be compared to the levels of the metabolites in a control or reference sample.
[0073] The methods and kits described herein (also with any of the sets of metabolite biomarkers described herein) may be applied to the assessment of diseases associated with the contact activation system (such as those described herein).
[0074] (ii) Diagnostic and / or prognostic uses The levels of the metabolites presented in Table 1 detected in samples from subjects can be used as reliable biomarkers for diagnosing diseases associated with the contact activation system (e.g., HAE), monitoring the progression of such diseases, assessing the effectiveness of treatments for the diseases, identifying patients suitable for particular treatments, and / or predicting attacks of the disease in subjects.
[0075] Thus, described herein are diagnostic and prognostic methods for diseases associated with the contact activation system based on the levels of a set of biomarkers in a biological sample obtained from a subject. In some embodiments, the levels of the biomarkers measured using any of the methods described herein can be used to assess whether a subject (e.g., a human patient) from whom the biological sample was obtained has or is at risk for a disease associated with the contact activation system, such as a plasma kallikrein-associated disease (e.g., HAE) or an autoimmune disease (such as RA, UC, and Crohn's disease).
[0076] In some embodiments, the level of the biomarker may then be compared to a reference sample or control sample to determine a value indicative of the amount of the metabolite in the sample. In some embodiments, the value for the biomarker is obtained by comparing the level of the metabolite in the sample to the level of another metabolite (e.g., an internal control or internal standard) in the sample. Such a biomarker value may be normalized to the internal control or internal standard. The value of the biomarker may be compared to a reference value to determine whether a subject has or is at risk for a disease associated with the contact activation system. The reference value may represent the level of the corresponding biomarker in a subject (e.g., a human subject) who does not have the target disease. In some embodiments, if the level or value of the biomarker is higher than the reference level or value, the subject may be identified as having or at risk for a disease associated with the contact activation system. In some embodiments, if the level or value of the biomarker is lower than the reference level or value, the subject may be identified as having or at risk for a disease associated with the contact activation system.
[0077] In some embodiments, the level of the biomarker may be compared to a predetermined threshold for that metabolite, deviation from which may indicate that the subject has a disease associated with the contact system. The predetermined threshold may represent a value of the biomarker that distinguishes between the level of the biomarker in patients with the target disease and the level of the biomarker in patients without the target disease.
[0078] In some embodiments, the set of biomarkers includes two or more metabolites that are differentially present (elevated and / or decreased) in subjects with or at risk of having a disease compared to healthy individuals. In some examples, the set of biomarkers includes at least one metabolite biomarker that is elevated in subjects with or at risk of having a disease and at least one metabolite biomarker that is decreased in subjects with or at risk of having a disease. In some embodiments, the set of biomarkers includes two or more metabolite biomarkers that have elevated levels in subjects with or at risk of having a disease compared to healthy controls. In other embodiments, the set of biomarkers includes two or more metabolite biomarkers that have decreased levels in subjects with or at risk of having a disease compared to healthy controls.
[0079] In some embodiments, the control or reference sample is a biological sample obtained from a healthy individual. In some embodiments, the control or reference sample contains known amounts of the metabolite being evaluated.
[0080] As used herein, a control sample may be a healthy subject or individual who is known to be free of the target disease (e.g., a disease associated with the contact system) or has no history of the disease at the time the level of the metabolite(s) is measured.
[0081] The term "control subject" includes an individual subject or a group of subjects with similar characteristics (e.g., a group of healthy individuals with certain characteristics (e.g., age, sex, ethnicity, etc.) matching those of a candidate subject). In some embodiments, the level of a biomarker in a control subject is used to establish a reference value (e.g., the average level of a biomarker in control subjects encompassing a group of subjects) against which the level of the biomarker in a candidate or test subject can be compared.
[0082] The control level refers to the level of a set of metabolite biomarkers as described herein in a control subject. The control level may be a predetermined level or threshold. Such a predetermined level may represent the level of the metabolite in a population of subjects who do not have or are not at risk of the target disease (for example, the average level in a population of healthy subjects). It may also represent the level of the metabolite in a population of subjects who have the target disease.
[0083] The predetermined level can take various forms. For example, it can be a single cutoff value, such as a median or mean value. In some embodiments, such a predetermined level can be established based on comparative groups (such as one defined group known to have the target disease and another defined group known not to have the target disease). Alternatively, the predetermined level can be a range (e.g., a range representing the level of the metabolite in a control population).
[0084] The control level as described herein can be determined by conventional techniques. In some cases, the control level can be obtained by performing a conventional method (e.g., the same assay as that used to obtain the level of the metabolite in the test sample as described herein) on a control sample as described herein. In other cases, the level of the metabolite can be obtained from members of a control population, and the results can be analyzed, for example, by a computer program, to obtain a control level (predetermined level) that represents the level of the metabolite in the control population.
[0085] By comparing the level of biomarkers in a sample obtained from a candidate subject with a reference value as described herein, it can be determined whether the candidate subject has or is at risk for a disease associated with the contact system (e.g., HAE). For example, if the level of biomarker(s) in the candidate subject's sample deviates from the reference value (e.g., is increased compared to the reference value), the candidate subject may be identified as having or at risk for the disease. If the reference value represents a range of values for the level of biomarkers in a population of subjects with the target disease, a value of biomarker in the candidate sample within that range indicates that the candidate subject has or is at risk for the target disease.
[0086] As used herein, an "elevated level" or "level above a reference value" means that the level of a biomarker is higher than a reference value (e.g., a predetermined threshold for the level of the biomarker in a control sample). Control levels are described in detail herein. Elevated levels of a biomarker include levels of the biomarker that are, for example, 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 150%, 200%, 300%, 400%, or 500% or more above the reference value. In some embodiments, the level of the biomarker in the test sample is at least 1.1 fold, 1.2 fold, 1.3 fold, 1.4 fold, 15 fold, 1.6 fold, 1.7 fold, 1.8 fold, 1.9 fold, 2 fold, 2.5 fold, 3 fold, 3.5 fold, 4 fold, 4.5 fold, 5 fold, 5 fold, 6 fold, 7 fold, 8 fold, 9 fold, 10 fold, 50 fold, 100 fold, 150 fold, 200 fold, 300 fold, 400 fold, 500 fold, 1000 fold, or 10,000 fold or more higher than the level of the biomarker in the reference sample.
[0087] As used herein, a "decreased level" or "level below a reference value" means that the level of a biomarker is lower than a reference value (e.g., a predetermined threshold value for the biomarker in a control sample). Control levels are described in detail herein. A reduced level of a biomarker includes a level of the biomarker that is, for example, 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 150%, 200%, 300%, 400%, or 500% or more lower than the reference value. In some embodiments, the level of the biomarker in the test sample is at least 1.1 fold, 1.2 fold, 1.3 fold, 1.4 fold, 15 fold, 1.6 fold, 1.7 fold, 1.8 fold, 1.9 fold, 2 fold, 2.5 fold, 3 fold, 3.5 fold, 4 fold, 4.5 fold, 5 fold, 5 fold, 6 fold, 7 fold, 8 fold, 9 fold, 10 fold, 50 fold, 100 fold, 150 fold, 200 fold, 300 fold, 400 fold, 500 fold, 1000 fold, or 10,000 fold or more lower than the level of the biomarker in the reference sample.
[0088] In some embodiments, the candidate subject is a human patient with symptoms of a disease associated with the contact activation system, such as a pKal-mediated disorder (e.g., HAE) or an autoimmune disease (such as RA, UC, and Crohn's disease). For example, the subject has edema; swelling that is entirely or mainly peripheral; hives; redness, pain, and swelling in the absence of evidence of infection; non-histamine-mediated edema; recurrent bouts of swelling; or a combination thereof. In other embodiments, the subject does not have symptoms of a pKal-mediated disorder at the time the sample is collected, or does not have a history of symptoms of a pKal-mediated disorder, or does not have a history of a pKal-mediated disorder, such as HAE. In yet other embodiments, the subject is resistant to antihistamine therapy, corticosteroid therapy, or both.
[0089] Subjects identified by the methods described herein may receive suitable treatment, such as treatment with a pKal inhibitor, as described herein.
[0090] Given the correlation between biomarker levels and such diseases, the assays and kits described herein can also be applied to assess the effectiveness of treatments for diseases associated with the contact system (such as those described herein). For example, multiple biological samples (e.g., blood or plasma samples) may be collected from a subject receiving treatment before and after treatment or during the course of treatment. The level of the biomarker may be measured by any of the assays described herein, and the value (e.g., amount) of the biomarker may be determined accordingly. For example, if an elevated level of a biomarker indicates that the subject has the target disease, and the level of the biomarker decreases after or over the course of treatment (the level of the biomarker in a later sample compared to the level of the biomarker in an earlier sample), it indicates that the treatment is effective. As another example, if a decreased level of a biomarker indicates that the subject has the target disease, and the level of the biomarker increases after or over the course of treatment (the level of the biomarker in a later sample compared to the level of the biomarker in an earlier sample), it indicates that the treatment is effective. In some examples, the treatment involves an effective amount of a therapeutic agent, such as a plasma kallikrein inhibitor, a bradykinin B2 receptor antagonist, or a C1 esterase inhibitor (C1-INH). Examples of therapeutic agents include, but are not limited to, lanadelumab, ecallantide, icatibant, and human plasma-derived C1-INH.
[0091] If a subject is identified as not responding to treatment, a higher dose and / or more frequent administration of the therapeutic agent is administered to the identified subject. In some embodiments, the dosage or administration frequency of the therapeutic agent is maintained, reduced, or discontinued in subjects who are identified as responding to treatment or not requiring further treatment. Alternatively, a different treatment may be administered to subjects who are found not to respond to the first treatment.
[0092] In other embodiments, the value of a biomarker or set of biomarkers can also be used to identify a disorder associated with the contact system or that the disorder may be treatable, for example, by a pKal inhibitor. To carry out this method, the level of a biomarker in a sample (e.g., a blood sample or plasma sample) taken from a subject with a target disease may be measured by a suitable method (e.g., mass spectrometry, chromatography, immunoassay, etc., as described herein). If the level of the biomarker deviates from the reference value (e.g., elevated or decreased), this indicates that a pKal inhibitor may be effective in treating the disease. If the disease is identified as sensitive to a pKal inhibitor (i.e., treatable by a pKal inhibitor), the method may further include administering to the subject with the disease an effective amount of a pKal inhibitor (e.g., an anti-pKal antibody or an inhibitory peptide (e.g., lanadelumab, ecallantide, etc.)), a bradykinin 2 receptor inhibitor (e.g., icatibant), and / or C1-INH (e.g., human plasma-derived C1-INH).
[0093] Also within the scope of the present disclosure are methods for assessing the severity of or pathology of diseases associated with the contact system. For example, as described herein, HAE can be in a quiescent state (basal state) during which the subject does not experience symptoms of the disease. HAE attacks are recurrent episodes that can typically last 2-5 days and during which the subject may experience pain and swelling, for example, in the hands, feet, face, gastrointestinal tract, genitals, and pharynx (throat). In some embodiments, the level of one or more biomarkers indicates whether the subject will experience, is experiencing, or will soon experience an HAE attack. In some embodiments, the method involves comparing the level of a biomarker in a sample obtained from a subject with HAE with the level of that biomarker in a sample obtained from the same subject (e.g., a sample obtained from the same subject in a basal state or a sample obtained from the same subject during an HAE attack).
[0094] Another aspect of the present disclosure provides a method for assessing the risk of a disease attack (e.g., an HAE attack). As described herein, HAE attacks are typically recurring episodes during which a subject may experience symptoms (such as pain and swelling). In some embodiments, the level of one or more biomarkers indicates whether a subject is at risk for an HAE attack. In some embodiments, the method involves comparing the level of a biomarker in a sample obtained from a subject with HAE with the level of that biomarker in a sample obtained from the same subject (e.g., a sample obtained from the same subject in an underlying condition or during an HAE attack). For example, an elevated (or decreased) level of a biomarker associated with an HAE attack compared to the level of the biomarker in another sample from the subject may indicate that the subject is at risk for an HAE attack.
[0095] In some embodiments, the method involves comparing the level of a biomarker in a sample obtained from a subject with HAE with the level of a biomarker in a control sample or reference sample. In some embodiments, the level of a biomarker in a control sample or reference sample represents the level of a biomarker that indicates an HAE attack state. For example, a biomarker level in a sample obtained from a subject with HAE that is similar to the level of a biomarker in a reference that indicates an HAE attack state may indicate that the subject is at risk of having an HAE attack. In some embodiments, the level of a biomarker in a control sample or reference sample represents the level of a biomarker that indicates an underlying HAE state. For example, a biomarker level in a sample obtained from a subject with HAE that deviates (is elevated or decreased) from the level of a biomarker in a reference that indicates an underlying HAE state may indicate that the subject is at risk of having an HAE attack.
[0096] (iii) Non-clinical use Furthermore, the levels of any of the sets of biomarkers described herein may be used for research purposes. Although a number of diseases associated with the contact activation system have been identified, it is possible that other diseases are mediated by similar mechanisms or involve similar components. In some embodiments, the methods described herein may be used to identify diseases as being associated with the contact activation system or components of the contact activation system. In some embodiments, the methods described herein may be used to study the mechanisms (e.g., discovering new biological pathways or processes involved in the development of a disease) or progression of a disease.
[0097] In some embodiments, the levels of a set of biomarkers as described herein may be utilized in the development of new treatments for diseases associated with the contact activation system. For example, the levels of the set of biomarkers may be measured in samples obtained from subjects undergoing a new treatment (e.g., a clinical trial). In some embodiments, the levels of the set of biomarkers may indicate the effectiveness of the new treatment or the progression of disease in the subject before, during, or after the new treatment.
[0098] Kits and detection devices for measuring a set of metabolite biomarkers - Patent Application 20070122999 The present disclosure also provides kits and detection devices for use in measuring levels of a set of biomarkers as described herein. Such kits or detection devices may include binding substances that specifically bind to metabolic biomarkers (such as those listed in Table 1). For example, such kits or detection devices may include at least two binding substances specific for two different metabolic biomarkers selected from Table 1. In some examples, the kits or detection devices include binding substances specific for all members of the set of metabolic biomarkers described herein.
[0099] In some embodiments, one or more of the binding agents is an antibody that specifically binds to a metabolite of the set of biomarkers, hi some embodiments, one or more of the binding agents is an aptamer (such as a peptide aptamer or an oligonucleotide aptamer) that specifically binds to a metabolite of the set of biomarkers.
[0100] In some embodiments, the kit further comprises a detecting agent (e.g., an antibody that binds to the binding agent) for detecting binding of the binding agent to a metabolite(s) of the set of biomarkers. The detecting agent may be conjugated to a label. In some embodiments, the detecting agent is an antibody that specifically binds to at least one of the binding agents. In some embodiments, the binding agent comprises a tag that can be identified by the detecting agent and to which the detecting agent can bind directly or indirectly.
[0101] In some embodiments, the kit or device further comprises a support member. In some embodiments, the support member is a membrane such as a nitrocellulose membrane, a polyvinylidene fluoride (PVDF) membrane, or a cellulose acetate membrane. In some examples, the immunoassay may be in the format of a Western blot assay or a lateral flow assay.
[0102] In some embodiments, the support member is a multiwell plate such as an ELISA plate. In some embodiments, the immunoassays described herein may be performed on a high-throughput platform. In some embodiments, multiwell plates (e.g., 24-well, 48-well, 96-well, or 384-well or greater plates) may be used for high-throughput immunoassays. Individual immunoassays may be performed simultaneously in each well. Therefore, it is generally desirable to measure multiple wells simultaneously using a plate reader to increase assay throughput. In some embodiments, plate readers capable of simultaneously imaging multiple wells (e.g., 4-well, 16-well, 24-well, 48-well, 96-well, or 384-well or greater) may be used for this platform. For example, commercially available plate readers (e.g., the plate::vision system available from Perkin Elmer (Waltham, MA)) may be used. This plate reader is capable of dynamic fluorescence analysis. The plate::vision system has high-light-gathering efficiency optics and special optics designed for simultaneous analysis of 96 wells. Additional suitable parallel plate readers include, but are not limited to, SAFIRE (Tecan, San Jose, CA), FLIPRTETRA® (Molecular Devices, Union City, CA), FDSS7000 (Hamamatsu, Bridgewater, NJ), and CellLux (Perkin Elmer, Waltham, MA).
[0103] In the kit or detection device, one or more of the binding substances may be immobilized on a support member, which may be a membrane, bead, slide, or multi-well plate. The selection of an appropriate support member for an immunoassay will depend on various factors, such as the number of samples and the method for detecting the signal emitted from the label conjugated to the second agent.
[0104] The kit may also include one or more buffers as described herein (including but not limited to a coating buffer, a blocking buffer, a washing buffer and / or a stopping buffer).
[0105] In some embodiments, the kit may include instructions for use according to any of the methods described herein. The included instructions may include instructions on how to use the components included in the kit to measure levels of metabolites of a set of biomarkers in a biological sample taken from a subject, such as a human patient.
[0106] The instructions for using the kit generally include information about the amount of each component and suitable conditions for carrying out the assay methods described herein. The components in the kit may be in unit dose, bulk package (e.g., multi-dose package), or sub-unit dose. The instructions provided in the kits of the present disclosure are typically written instructions on a label or package insert (e.g., a paper sheet included in the kit), although machine-readable instructions (e.g., instructions carried on a magnetic or optical storage disk) are also acceptable.
[0107] The label or package insert indicates that the kit is used for assessing levels of metabolites of the set of biomarkers. Instructions may be provided for performing any of the methods described herein.
[0108] The kits of the present disclosure are contained in suitable packaging. Suitable packaging includes, but is not limited to, vials, bottles, jars, flexible packaging (e.g., sealed Mylar or plastic bags), and the like. Also contemplated are packages for use in combination with specific devices, such as inhalers, intranasal administration devices (e.g., nebulizers), or infusion devices (e.g., minipumps). The kits may have a sterile access port (e.g., the container may be an intravenous solution bag or a vial with a stopper pierceable by a hypodermic needle). The container may also have a sterile access port (e.g., the container may be an intravenous solution bag or a vial with a stopper pierceable by a hypodermic needle).
[0109] The kit may optionally provide additional components, such as information for determination (such as a control sample and / or a standard or reference sample). Typically, the kit includes a container and a label or package insert(s) on or associated with the container. In some embodiments, the present disclosure provides an article of manufacture comprising the contents of the above-described kit.
[0110] Treatment of diseases associated with the contact activation system Subjects identified using the methods described herein as being at risk for or suffering from a disease associated with the contact activation system may be treated with any appropriate therapeutic agent. In some embodiments, the methods provided include selecting a treatment for the subject based on the output of the described methods (e.g., measuring the levels of a set of biomarkers).
[0111] In some embodiments, the methods described herein provide a method for identifying a subject as a candidate for preventative (prophylactic) treatment. As used herein, "preventative" treatment encompasses any therapy or treatment regimen aimed at preventing or reducing the occurrence of a disease (e.g., an HAE attack). In some embodiments, the method further includes administering a preventative treatment to the subject. Any of the therapeutic agents described herein (e.g., a pKal inhibitor such as lanadelumab). In some embodiments, the level of a set of metabolite biomarkers in a sample obtained from the subject indicates that the patient has or is at risk of having HAE (e.g., by comparing the level of the metabolite biomarkers to levels in a reference or control sample). Any subject with HAE or at risk of having HAE may be administered a prophylactic treatment. The selection of an appropriate therapeutic agent and administration regimen for preventative treatment will be apparent to one skilled in the art.
[0112] In some embodiments, the method includes one or both of selecting or administering a therapeutic agent (e.g., a kallikrein inhibitor, a bradykinin B2 receptor inhibitor, and / or a C1 esterase inhibitor) for administration to the subject based on the output of the assay (e.g., detection of a biomarker).
[0113] In some embodiments, the therapeutic agent is administered to the subject one or more times. In some embodiments, a plasma kallikrein inhibitor is administered to the subject. In some embodiments, the kallikrein inhibitor is a peptide, a small molecule inhibitor, a kallikrein antibody or a fragment thereof. In some embodiments, a bradykinin B2 receptor antagonist is administered to the subject. In some embodiments, C1-INH is administered to the subject.
[0114] A therapeutic agent (e.g., a kallikrein inhibitor, a bradykinin B2 receptor inhibitor, and / or C1-INH) may be administered together with another therapy as part of a combination therapy for the treatment of a disease or condition involving the contact activation system. The combination therapy (e.g., a combination therapy with one or more of a kallikrein inhibitor, a bradykinin B2 receptor antagonist, or a C1-INH replacement agent, e.g., a combination therapy with one or more of a kallikrein inhibitor, a bradykinin B2 receptor antagonist, or a C1-INH replacement agent and another therapy) may be provided in several different configurations. A first agent may be administered before or after the administration of the other therapy. In some situations, the first agent and the other therapy (e.g., a therapeutic agent) are administered simultaneously or closely in time (e.g., with a short injection interval, such as during the same treatment session). The first agent and the other therapy may also be administered at a longer time interval.
[0115] Treatment drugs Plasma kallikrein binding agents (e.g., binding proteins, e.g., polypeptides, e.g., inhibitory polypeptides, e.g., antibodies, e.g., inhibitory antibodies, or other binding agents (e.g., small molecules)) are useful therapeutic agents for various diseases and conditions (e.g., diseases and conditions associated with plasma kallikrein activity). For example, in some embodiments, the disease or condition associated with plasma kallikrein activity is hereditary angioedema (HAE). In some embodiments, a plasma kallikrein binding agent, such as a plasma kallikrein inhibitor, is administered to a subject at risk for or suffering from a disease associated with the contact activation system.
[0116] Some useful protein-based inhibitors of kallikrein (either tissue kallikrein and / or plasma kallikrein) contain a Kunitz domain. As used herein, a "Kunitz domain" is a polypeptide domain having at least 51 amino acids and containing at least two (preferably three) disulfides. This domain folds so that the first and sixth cysteines, the second and fourth, and the third and fifth cysteines form disulfide bonds (e.g., in a 58-amino acid Kunitz domain, cysteines may be present at positions corresponding to amino acids 5, 14, 30, 38, 51, and 55 according to the numbering of the BPTI homologous sequence presented below, and disulfides may be formed between the cysteines at positions 5 and 55, 14 and 38, and 30 and 51). Alternatively, if two disulfides are present, they may be formed between corresponding subsets of the cysteines. The spacing between each cysteine can be within 7, 5, 4, 3, 2, 1, or 0 amino acids of the spacing between positions corresponding to positions 5-55, 14-38, and 30-51 according to the numbering of the BPTI sequence presented below. The BPTI sequence can be used as a reference to point to specific positions in any general Kunitz domain. Comparison of a Kunitz domain of interest to BPTI can be performed by identifying the best-match alignment that maximizes the number of matching cysteines.
[0117] The 3D structure (at high resolution) of the Kunitz domain of BPTI is known. One X-ray structure has been deposited in the Brookhaven Protein Data Bank as "6PTI." The 3D structures of several BPTI homologs (Eigenbrot et al., Protein Engineering (1990) 3(7):591-598; Hynes et al., Biochemistry (1990) 29:10018-10022) are known. The sequences of at least 81 Kunitz domains are known. Known human homologs include the three Kunitz domains of LACI, also known as tissue factor pathway inhibitor (TFPI) (Wun et al., J.Biol.Chem.(1988) 263(13):6001-6004; Girard et al., Nature(1989) 338:518-20; Novotny et al., J.Biol.Chem.(1989) 264(31):18832-18837), the two Kunitz domains of inter-α-trypsin inhibitor APP-I (Kido et al. J.Biol.Chem.(1988) 263(34):18104-18107), the Kunitz domains of collagen, and the three Kunitz domains of TFPI-2 (Sprecher et al., PNAS USA(1994) 91:3353-3357), the Kunitz domain of hepatocyte growth factor activator inhibitor type 1, the Kunitz domain of hepatocyte growth factor activator inhibitor type 2, and the Kunitz domain described in U.S. Patent Application Publication No. 2004-0152633. LACI is a human serum phosphoglycoprotein with a molecular weight of 39 kDa that contains three Kunitz domains (amino acid sequence in Table 2).
[0118] [Table 2]
[0119] The Kunitz domains are designated LACI-K1 (residues 50-107), LACI-K2 (residues 121-178), and LACI-K3 (residues 213-270). The cDNA sequence of LACI was reported by Wun et al. (J. Biol. Chem. (1988) 263(13):6001-6004). Girard et al. (Nature (1989) 338:518-20) reported mutational studies in which the P1 residues of each of the three Kunitz domains were altered. LACI-K1 inhibits factor VIIa (F.VIIa) when it is complexed with tissue factor, and LACI-K2 inhibits factor Xa.
[0120] Exemplary Kunitz domain-containing proteins include the following (SWISS-PROT accession numbers in parentheses): [ka]
[0121] Kunitz domains can be identified from sequence databases using various methods. For example, known amino acid sequences, consensus sequences, or motifs (e.g., ProSite Motifs) of Kunitz domains can be searched against the GenBank sequence database (National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD) using BLAST (e.g., using default parameters for Pfam searches; against the SMART database; or against the ProDom database) for HMMs (hidden Markov models). For example, Pfam Release 9, Pfam accession number PF00014, provides numerous Kunitz domains and HMMs for identifying Kunitz domains. A description of the Pfam database can be found in Sonhammer et al. Proteins (1997) 28(3):405-420, and a detailed description of HMMs can be found, for example, in Gribskov et al. Meth. Enzymol. (1990) 183:146-159; Gribskov et al. Proc. Natl. Acad. Sci. USA (1987) 84:4355-4358; Krogh et al. J. Mol. Biol. (1994) 235:1501-1531; and Stultz et al. Protein Sci. (1993) 2:305-314. The SMART database of HMMs (Simple Modular Architecture Research Tool, EMBL, Heidelberg, DE) is as described in Schultz et al. Proc. Natl. Acad. Sci. USA (1998) 95:5857 and Schultz et al. Nucl. Acids Res (2000) 28:231.The SMART database contains domains identified by hidden Markov model profiling using the HMMer2 search program (R. Durbin et al. (1998) "Biological sequence analysis: probabilistic models of proteins and nucleic acids," Cambridge University Press). This database is also annotated and monitored. The ProDom protein domain database consists of an automated compilation of homologous domains (Corpet et al. Nucl. Acids Res. (1999) 27:263-267). The current version of ProDom was constructed using recursive PSI-BLAST searches of the SWISS-PROT 38 and TREMBL protein databases (Altschul et al. Nucleic Acids Res. (1997) 25:3389-3402; Gouzy et al. Computers and Chemistry (1999) 23:333-340). This database automatically generates consensus sequences for each domain. Prosite lists Kunitz domains as motifs and identifies proteins containing Kunitz domains (see, e.g., Falquet et al. Nucleic Acids Res. (2002) 30:235-238).
[0122] Kunitz domains interact with target proteases primarily using amino acids in two loop regions ("binding loops"). The first loop region is located approximately between residues corresponding to amino acids 13-20 of BPTI. The second loop region is located approximately between residues corresponding to amino acids 31-39 of BPTI. In an exemplary library of Kunitz domains, one or more amino acid positions within the first and / or second loop regions are varied. When screening for Kunitz domains that interact with kallikrein or selecting variants with improved affinity, particularly useful positions to vary include positions 13, 15, 16, 17, 18, 19, 31, 32, 34, and 39 relative to the sequence of BPTI. At least some of these positions are expected to be in close contact with the target protease. Varying other positions (e.g., positions adjacent to the aforementioned positions in the three-dimensional structure) is also useful.
[0123] The "framework regions" of a Kunitz domain are defined as residues that are part of the Kunitz domain, but specifically exclude residues within the first and second binding loop regions (i.e., around residues corresponding to amino acids 13-20 of BPTI and amino acids 31-39 of BPTI). Conversely, residues not within the binding loops may tolerate a broader range of amino acid substitutions (e.g., conservative and / or non-conservative substitutions).
[0124] In one embodiment, these Kunitz domains are variants of the loop structure comprising Kunitz domain 1 of human lipoprotein-associated coagulation inhibitor (LACI). LACI contains three well-defined internal peptide loop structures that are paradigm Kunitz domains (Girard, T. et al., Nature (1989) 338:518-520). Variants of Kunitz domain 1 of LACI described herein have been screened and isolated, and they bind to kallikrein with improved affinity and specificity (see, e.g., U.S. Patent Nos. 5,795,865 and 6,057,287). These methods can also be applied to the frameworks of other Kunitz domains to obtain other Kunitz domains that interact with kallikrein (e.g., plasma kallikrein). Useful modulators of kallikrein function typically bind to and / or inhibit kallikrein as determined using kallikrein binding and kallikrein inhibition assays.
[0125] In some aspects, the plasma kallikrein inhibitor binds to the active form of plasma kallikrein. In some embodiments, the plasma kallikrein inhibitor binds to and inhibits plasma kallikrein (e.g., human plasma kallikrein and / or mouse kallikrein). Exemplary polypeptide-based plasma kallikrein drugs are disclosed in U.S. Patent No. 5,795,865, U.S. Patent No. 5,994,125, U.S. Patent No. 6,057,287, U.S. Patent No. 6,333,402, U.S. Patent No. 7,628,983, U.S. Patent No. 8,283,321, U.S. Patent No. 7,064,107, U.S. Patent No. 7,276,480, U.S. Patent No. 7,851,442, U.S. Patent No. 8,124,586, U.S. Patent No. 7,811,991 and U.S. Patent Application Publication No. 20110086801, the entire contents of each of which are incorporated herein by reference. In some embodiments, the plasma kallikrein inhibitor is an inhibitory polypeptide or inhibitory peptide. In some embodiments, the inhibitory peptide is ecallantide (also known as DX-88 or KALBITOR®; SEQ ID NO: 3). In some embodiments, the kallikrein inhibitor comprises or consists of a DX-88 polypeptide having a sequence of about 58 amino acids from amino acids 3 to 60 of SEQ ID NO: 3, or the 60 amino acid sequence of SEQ ID NO: 3.
[0126] Glu Ala Met His Ser Phe Cys Ala Phe Lys Ala Asp Asp Gly Pro Cys Arg Ala Ala His Pro Arg Trp Phe Phe Asn Ile Phe Thr Arg Gln Cys Glu Glu Phe Ile Tyr Gly Gly Cys Glu Gly Asn Gln Asn Arg Phe Glu Ser Leu Glu Glu Cys Lys Lys Met Cys Thr Arg Asp (SEQ ID NO: 3).
[0127] The plasma kallikrein inhibitor may be a full-length antibody (e.g., IgG (e.g., IgG1, IgG2, IgG3, IgG4), IgM, IgA (e.g., IgA1, IgA2), IgD, and IgE) or may comprise only an antigen-binding fragment (e.g., a Fab fragment, a F(ab')2 fragment, or an scFv fragment). The binding protein may comprise two heavy chain immunoglobulins and two light chain immunoglobulins, or may be a single-chain antibody. The plasma kallikrein inhibitor may be a recombinant protein, such as a humanized antibody, a CDR-grafted antibody, a chimeric antibody, a deimmunized antibody, or an in vitro generated antibody, and may optionally comprise a constant region derived from a human germline immunoglobulin sequence. In one embodiment, the plasma kallikrein inhibitor is a monoclonal antibody.
[0128] Exemplary plasma kallikrein binding proteins are disclosed in U.S. Patent Application Publication No. 20120201756, the entire contents of which are incorporated herein by reference. In some embodiments, the kallikrein binding protein is selected from the group consisting of M162-A04, M160-G12, M142-H08, X63-G06, X101-A01 (also referred to as DX-2922), X81-B01, X67-D03, X67-G04, X81-B01, X67-D03, X67-G04, X115-B07, X115-D05, X115-E09, X115-E10, X115-E11, X115-E12, X115-E13, X115-E14, X115-E15, X115-E16, X115-E17, X115-E18, X115-E19, X115-E20, X115-E21, X115-E22, X115-E23, X115-E24, X115-E25, X115-E26, X115-E27, X115-E28, X115-E29, X115-E30, X115-E31, X115-E32, X115-E33, X115-E34, X115-E35, X115-E36, X115-E37, X115-E38, X115-E39, X115-E40, X115-E41, X115-E42, X115-E43, X115-E and an antibody (e.g., a human antibody) having a light chain and / or a heavy chain of an antibody selected from the group consisting of 115-H06, X115-A03, X115-D01, X115-F02, X124-G01 (also referred to herein as DX-2930 or lanadelumab), X115-G04, M29-D09, M145-D11, M06-D09, and M35-G04. In some embodiments, the plasma kallikrein binding protein competes with or binds to the same epitope as M162-A04, M160-G12, M142-H08, X63-G06, X101-A01 (also referred to herein as DX-2922), X81-B01, X67-D03, X67-G04, X81-B01, X67-D03, X67-G04, X115-B07, X115-D05, X115-E09, X115-H06, X115-A03, X115-D01, X115-F02, X124-G01, X115-G04, M29-D09, M145-D11, M06-D09, and M35-G04. In some embodiments, the plasma kallikrein binding protein is lanadelumab. See U.S. Patent Application Publication Nos. 20110200611 and 20120201756, which are incorporated herein by reference.
[0129] An example of a plasma kallikrein inhibitor antibody is lanadelumab. The amino acid sequences of the heavy and light chain variable regions of lanadelumab are provided below, with the CDR regions identified in bold and underlined.
[0130] Lanadelumab heavy chain variable region sequence (SEQ ID NO: 4) EVQLLESGGG LVQPGGSLRL SCAASGFTFS HYIMMWVRQA PGKGLEWVSG IYSSGGITVY ADSVKGRFTI SRDNSKNTLY LQMNSLRAED TAVYYCAYRR IGVPRRDEFD IWGQGTMVTV SS
[0131] Lanadelumab light chain variable region sequence (SEQ ID NO: 5) DIQMTQSPS TLSASVGDRV TITCRASQSI SSWLAWYQQK PGKAPKLLIY KASTLESGVP SRFSGSGSGT EFTLTISSLQ PDDFATYYCQ QYNTYWTFGQ GTKVEI
[0132] In some embodiments, a plasma kallikrein inhibitor may have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more sequence identity to a plasma kallikrein inhibitor described herein. In some embodiments, a plasma kallikrein inhibitor may have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more sequence identity in the framework regions of the HC and / or LC (e.g., FR1, 2, 3, and / or 4 of the HC and / or LC) to a plasma kallikrein inhibitor described herein. In some embodiments, a plasma kallikrein inhibitor may have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more sequence identity in the CDRs of the HC and / or LC (e.g., CDR1, 2, and / or 3 of the HC and / or LC) to a plasma kallikrein inhibitor described herein. In some embodiments, a plasma kallikrein inhibitor may have about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% or more sequence identity in the constant region (e.g., CH1, CH2, CH3, and / or CL1) to a plasma kallikrein inhibitor described herein.
[0133] In some aspects, the small molecule binds to and inhibits the active form of plasma kallikrein.
[0134] Bradykinin B2 receptor inhibitor In some embodiments, a bradykinin B2 receptor inhibitor (e.g., antagonist) is administered to the subject. Exemplary bradykinin B2 receptor antagonists include icatibant (Firadyl®), a 10-amino acid peptidomimetic that blocks the binding of native bradykinin to the bradykinin B2 receptor.
[0135] C1-INH replacement In some embodiments, a C1 esterase inhibitor (C1-INH), such as a C1-INH replacement drug, is administered to the subject. Exemplary C1-INH replacement drugs are publicly available and include, for example, human plasma-derived C1-INH (e.g., Verinert® and Sinrise®).
[0136] Without further elaboration, it is believed that, based on the above description, one skilled in the art can utilize the present disclosure to its fullest extent. Accordingly, the following specific embodiments are to be construed as merely illustrative, and not limiting in any way to the remainder of the disclosure. All publications cited herein are incorporated by reference for the purpose or subject matter referenced herein. [Example]
[0137] Example Example 1: Identification of metabolites that are differentially present in samples from HAE patients compared to healthy individuals To investigate novel metabolic biomarkers of hereditary angioedema, we performed an analysis comparing the metabolite composition of plasma samples obtained from patients with HAE with that of healthy individuals. Citrated plasma was collected from 20 healthy individuals and 20 patients with HAE during a quiescent state of the disease ("basal state") and during edematous attacks ("attacks"). The samples were subjected to a validated liquid chromatography-mass spectrometry (LC-MS) method to detect metabolites present in the samples. This analysis detected 1,069 distinct plasma metabolites. The abundance of each metabolite was compared between samples and subjected to statistical analysis.
[0138] As shown in Table 3, 187 different metabolites were differentially present in samples from HAE patients at basal state compared to healthy individuals (73 elevated and 114 decreased), 156 different metabolites were differentially present in samples from HAE patients during an attack compared to healthy individuals (51 elevated and 105 decreased), and 59 different metabolites were differentially present in samples from HAE patients during an attack compared to HAE patients at basal state (25 elevated during an attack and 34 decreased during an attack).
[0139] [Table 3]
[0140] Random forest analysis showed separation of HAE patients from healthy individuals with a classification accuracy of 78% (Figure 1, panel A) and separation of HAE patients in the basal state from HAE patients during an attack with a classification accuracy of 20% (Figure 1, panel B).
[0141] Metabolomic analysis of samples from HAE patients compared with healthy individuals Metabolomic comparison of samples from HAE patients and healthy individuals identified several promising metabolites that exhibited disease-specific differences in the levels detected in plasma samples. For example, the neurotransmitter serotonin was found to be significantly elevated in plasma samples from HAE patients compared with plasma samples from healthy individuals (P < 0.05, Welch's two-sample t-test), particularly during HAE attacks (Table 4; Figure 2, panel A). The serotonin precursor tryptophan was found to be decreased in plasma samples from HAE patients compared with plasma samples from healthy individuals, further indicating that serotonin metabolism is altered during HAE. Other metabolites involved in the production of serotonin (e.g., indole lactic acid and indole propionic acid) were also found to be significantly different between HAE patients and healthy individuals (Table 4).
[0142] [Table 4]
[0143] Serotonin is a neurotransmitter and vasoactive amine that acts on the central nervous system, gastrointestinal tract, and platelets, and is involved in regulating vascular tone. When serotonin levels were classified based on the rate of HAE attacks, we observed that serotonin levels were highest in patients with more frequent HAE attacks (more than two attacks per month) (Figure 2, Panel B). Therefore, detecting serotonin levels may be useful in identifying patients with more active disease or whose disease is less likely to be suppressed by treatment.
[0144] Several metabolites related to fatty acid amide hydrolase (FAAH) activity were significantly increased in samples from patients with HAE, suggesting a decrease in FAAH activity in HAE patients (Table 5). For example, palmitamide, oleamide, and linoleamide (18:2n6) were significantly elevated in HAE plasma compared with healthy plasma (Table 5).
[0145] [Table 5]
[0146] Several lipid peroxidation markers, including 9 / 13-HODE, 9,10-DiHOME, 12,13-DiHOME, and 19,20 DiHDPA, were found to be decreased in samples from HAE patients compared to healthy individuals (Table 6), consistent with the expected reduction in membrane-associated oxidative stress in patients with HAE.
[0147] [Table 6]
[0148] The lipid-bound antioxidant gamma / beta-tocopherol was also found to have significantly elevated levels in samples from HAE patients (Table 7).
[0149] [Table 7]
[0150] The metabolomic data further suggested that sulfur metabolism and steroid metabolism may be involved in HAE. As shown in Table 8, many metabolites related to sulfur metabolism, including N-acetylmethionine, methionine sulfone, S-adenosylhomocysteine (SAH), cystine, and cysteine sulfinic acid, were detected at elevated levels. Several steroid metabolites, including cortisol, were detected at reduced levels in HAE patients compared with healthy individuals (Table 9).
[0151] [Table 8]
[0152] These results indicate that any of the metabolites identified in the metabolomics study could be used as biomarkers to distinguish samples from patients with HAE from healthy individuals. Furthermore, the study identified anti-inflammatory pathways, oxidative stress pathways, and steroid metabolism pathways as altered in HAE patients. These pathways may provide a potential source of novel biomarkers.
[0153] Metabolomic analysis comparing samples from patients with HAE in a basal state with samples from patients with HAE during an attack Metabolomic analysis also identified several metabolites present at different levels in patients with HAE in the basal state compared with those with HAE during attacks. Corticosterone, an intermediate in the formation of aldosterone, was found to be significantly decreased during HAE attacks (Table 9). Furthermore, several polyunsaturated fatty acids, including eicosapentaenoic acid, mead acid, and stearidonic acid, were found to be significantly elevated during attacks compared with those during the basal state (Table 10). Finally, two metabolic precursors of coenzyme A cofactors (nicotinamide and pantothenic acid) were observed to be significantly elevated during attacks compared with those during the basal state (Figure 10, panels A-C).
[0154] [Table 9] TIFF2025124816000013.tif195162
[0155] [Table 10]
[0156] [Table 11]
[0157] These results indicated that these metabolites (e.g., those with significant fold-change ratios) could be used alone or in combination as reliable biomarkers for HAE and other diseases associated with the contact system.
[0158] The metabolomic data also provided new insights into the pathobiology of HAE. For example, a subset of metabolites was associated with edema, including serotonin and lipid amides; metabolites related to oxidative stress such as oxidative limits, γ-tocopherol / β-tocopherol; and steroids. This analysis also provided new insights into the pathobiology of HAE during basal compared with attacks. For example, some of the differences between basal and attacks included anti-inflammatory lipid precursors, mineralocorticoids (corticosterone), and regulators of water and salt balance.
[0159] Metabolomic analysis has also identified a number of metabolites that are present at different levels between patients with HAE and healthy individuals, and between patients with HAE at baseline compared to during an attack. Any of the metabolites identified herein (e.g., metabolites with significant fold changes between HAE patients and healthy individuals) can be used (individually or in combination (in a set of biomarkers)) as biomarkers for diseases associated with the contact activation system in methods, for example, to identify patients at risk for a disease associated with the contact activation system (e.g., HAE), to select candidates for treatment, to monitor disease progression or disease state, to evaluate the effectiveness of treatment for a disease, to determine a course of treatment, to identify whether a disease or disorder is associated with the contact activation system, and / or for research purposes (e.g., including studying disease mechanisms that may be utilized for the development of new therapies).
[0160] Other embodiments All features disclosed herein may be combined in any combination. Each feature disclosed herein may be replaced by an alternative feature serving the same, equivalent, or similar purpose. Thus, unless expressly stated otherwise, each disclosed feature is only one example of a generic series of equivalent or similar features.
[0161] From the foregoing description, those skilled in the art can readily ascertain the essential features of the present disclosure, and can make various changes and modifications to the present disclosure to adapt it to various uses and conditions without departing from the spirit and scope thereof. Accordingly, other embodiments are within the scope of the following claims.
[0162] Equivalents and Scope Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the present disclosure described herein. The scope of the present disclosure is not intended to be limited to the above description, but rather is as set forth in the appended claims.
[0163] In the claims, articles such as "a," "an," and "the" can mean one or more unless indicated otherwise or clear from the context. A claim or description including "or" between one or more members of a group is deemed to stand if one, more than one, or all of the group members are present in, used in, or associated with a given product or process, unless indicated otherwise or clear from the context. The present disclosure includes embodiments in which exactly one member of a group is present in, used in, or associated with a given product or process. The present disclosure includes embodiments in which two or more, or all of the group members are present in, used in, or associated with a given product or process.
[0164] Furthermore, the present disclosure encompasses all variations, combinations, and permutations in which one or more limitations, elements, clauses, and descriptive terms from one or more of the enumerated claims are introduced into another claim. For example, any claim that depends on another claim may be modified to include one or more limitations found in any other claim that depends from the same base claim. Where elements are presented as a list (e.g., in Markush group format), each subgroup of elements is also disclosed, and any element(s) may be deleted from the group. In general, when the present disclosure or aspects of the present disclosure are referred to as comprising certain elements and / or features, it should be understood that certain embodiments of the present disclosure or aspects of the present disclosure consist of or consist essentially of such elements and / or features. For the sake of brevity, those embodiments have not been specifically described in those terms herein. It should also be noted that the terms "comprising" and "containing" are intended to be open-ended, permitting the inclusion of additional elements or steps. Where ranges are given, endpoints are included. Furthermore, unless otherwise indicated or apparent from the context and the understanding of one of ordinary skill in the art, values expressed as ranges may, in various embodiments of the present disclosure, assume any specific value or subrange within the stated range, to the nearest tenth of the lower limit of the range, unless the context clearly dictates otherwise.
[0165] This application refers to various issued patents, published patent applications, journal articles, and other publications, all of which are incorporated herein by reference. In the event of a conflict between any of the incorporated references and this specification, this specification shall control. Furthermore, any specific embodiments of the present disclosure that fall within the prior art may be expressly excluded from one or more of the claims. Such embodiments may be excluded even if the exclusion is not explicitly set forth herein because they are deemed to be known to those of ordinary skill in the art. Any specific embodiments of the present disclosure may be excluded from any claim for any reason, whether related to the existence of prior art or not.
[0166] Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments described herein. The scope of the embodiments described herein is not intended to be limited to the above description, but rather is as set forth in the appended claims. Those skilled in the art will appreciate that various changes and modifications to this description may be made without departing from the spirit or scope of the present disclosure as defined in the following claims.
Claims
[Claim 1] (i) providing a biological sample obtained from a subject having, suspected of having, or at risk for having a disease associated with the contact activation system; (ii) measuring the levels of a set of metabolic biomarkers; 1. A method for analyzing a sample, comprising: