Atypical hemolytic uremic syndrome (ahus) biomarker proteins

Abstract

The disclosure provides biomarker proteins, a change in the concentration or activity level of which are associated with atypical hemolytic uremic syndrome (aHUS) or clinically meaningful treatment of aHUS with a complement inhibitor. Also provided are compositions and methods for interrogating the concentration and/or activity of one or more of the biomarker proteins in a biological fluid. The compositions and methods are useful for, among other things, evaluating risk for developing aHUS, diagnosing aHUS, determining whether a subject is experiencing the first acute presentation of aHUS, monitoring progression or abatement of aHUS, and/or monitoring response to treatment with a complement inhibitor or optimizing such treatment.

1 - 297 . (canceled) 
     
     
         298 . A method for treating a patient having atypical hemolytic uremic syndrome (aHUS) whose blood or urine has been determined to contain elevated levels at least two aHUS-associated biomarker proteins selected from the group consisting of TNFR1, IL-6, proteolytic fragment Ba of complement component factor B, soluble C5b9 (sC5b9), prothrombin fragment F1+2, d-dimer, thrombomodulin, complement component C5a, β2 microglobulin (β2M), clusterin, cystatin C, fatty acid binding protein 1 (FABP-1), soluble CD40 ligand (sCD40L), vascular endothelial cell growth factor (VEGF), chemokine (C-X-C motif) ligand 9, chemokine (C-X-C motif) ligand 10, monocyte chemotactic protein-1, vascular cell adhesion molecule-1, and tissue inhibitor of metalloproteinases-1, the method comprising administering to the patient an inhibitor of complement C5 in an amount and with a frequency sufficient to reduce the concentration of the at least two aHUS-associated biomarker proteins compared to the concentration measured in the patient's blood or urine prior to treatment with the complement C5 inhibitor. 
     
     
         299 . The method of  claim 298 , wherein the subject:
 (a) has received dialysis at least once within the three months immediately prior to treatment with the complement C5 inhibitor; or   (b) is experiencing a first acute aHUS manifestation.   
     
     
         300 . The method of  claim 298 , wherein the reduced concentration of the at least two aHUS-associated biomarker proteins occurs within two weeks or two months after the first administration of the complement C5 inhibitor. 
     
     
         301 . The method of  claim 298 , wherein the subject is chronically treated with a complement C5 inhibitor. 
     
     
         302 . The method of  298 , wherein the complement C5 inhibitor is selected from the group consisting of a small molecule, a polypeptide, a polypeptide analog, a peptidomimetic, and an aptamer. 
     
     
         303 . The method of  298 , wherein the complement C5 inhibitor is selected from the group consisting of MB12/22, MB12/22-RGD, ARC187, ARC1905, SSL7, and OmCI. 
     
     
         304 . The method of  claim 298 , wherein the complement C5 inhibitor is an antibody, or an antigen-binding fragment thereof. 
     
     
         305 . The method of  claim 304 , wherein the antibody, or antigen-binding fragment thereof, is selected from the group consisting of a humanized antibody, a recombinant antibody, a diabody, a chimerized or chimeric antibody, a monoclonal antibody, a deimmunized antibody, a fully human antibody, a single chain antibody, an Fv fragment, an Fd fragment, an Fab fragment, an Fab′ fragment, and an F(ab′) 2  fragment. 
     
     
         306 . The method of  claim 304 , wherein the antibody, or antigen-binding fragment thereof, binds to complement component C5 and inhibits cleavage of C5 into fragments C5a and C5b. 
     
     
         307 . The method of  claim 306 , wherein the antibody is eculizumab or a variant of eculizumab. 
     
     
         308 . The method of  claim 307 , wherein the antigen-binding fragment is pexelizumab. 
     
     
         309 . The method of  claim 298 , wherein at least one of the aHUS-associated biomarkers is selected from the group consisting of: proteolytic fragment Ba of factor B, TNFR1, D-dimer, thrombomodulin, and cystatin C. 
     
     
         310 . The method of  claim 298 , wherein the at least two aHUS-associated biomarker proteins are measured using an immunoassay, such as an enzyme-linked immunosorbent assay (ELISA) or a radioimmunoassay (RIA). 
     
     
         311 . The method of  claim 298 , wherein the biological fluid is blood, a blood fraction, or urine. 
     
     
         312 . The method of  claim 311 , wherein the blood fraction is serum or plasma. 
     
     
         313 . The method of  claim 298 , wherein:
 (i) the concentration of at least one aHUS-associated biomarker is measured in two or more types of biological fluid; or   (ii) the concentration of a first of the at least two aHUS-associated biomarker proteins is measured in one type of biological fluid and the concentration of a second of the at least two aHUS biomarker proteins is measured in a second type of fluid.   
     
     
         314 . The method of  claim 298 , wherein:
 (i) the concentration of chemokine (C-X-C motif) ligand 9, chemokine (C-X-C motif) ligand 10, IL-6, monocyte chemotactic protein-1, vascular cell adhesion molecule-1, vascular endothelial cell growth factor (VEGF), sCD40L, or sTNFR1 in the serum of the subject is determined;   (ii) the concentration of at least one of β2 microglobulin (β2M), clusterin, cystatin C, fatty acid binding protein 1 (FABP-1), soluble C5b9 (sC5b9), tissue inhibitor of metalloproteinases, and complement component C5a in the urine of the subject is determined; and/or   (iii) the concentration of, proteolytic fragment Ba of complement component factor B, soluble C5b9 (sC5b9), prothrombin fragment F1+2, D-dimer, thrombomodulin, or von Willebrand Factor (vWF) in the plasma of the subject is determined.   
     
     
         315 . The method of  claim 298 , wherein the normal concentration of sTNFR1 is less than 2000 pg/mL. 
     
     
         316 . The method of  claim 298 , wherein the concentration of sTNFR1 in the biological sample is deemed elevated when it is:
 (i) at least two fold greater than the normal concentration of sTNFR1; or   (ii) at least 10,000 pg/mL.   
     
     
         317 . A method for diagnosing a subject as having or being at risk for developing atypical hemolytic uremic syndrome (aHUS), the method comprising: determining the concentration of at least two aHUS-associated biomarker proteins in a biological fluid obtained from a subject,
 wherein the aHUS-associated biomarker proteins are selected from the group consisting of: TNFR1, IL-6, proteolytic fragment Ba of complement component factor B, soluble C5b9 (sC5b9), prothrombin fragment F1+2, d-dimer, thrombomodulin, complement component C5a, β2 microglobulin (β2M), clusterin, cystatin C, fatty acid binding protein 1 (FABP-1), soluble CD40 ligand (sCD40L), vascular endothelial cell growth factor (VEGF), chemokine (C-X-C motif) ligand 9, chemokine (C-X-C motif) ligand 10, monocyte chemotactic protein-1, vascular cell adhesion molecule-1, and tissue inhibitor of metalloproteinases-1, and   wherein an elevated concentration of the at least two aHUS-associated biomarker proteins compared to the concentration of the aHUS-associated biomarker proteins measured in a sample of biological fluid of the same type indicates that the subject has, or is at risk for developing, aHUS.   
     
     
         318 . A method for monitoring responsiveness of a subject to treatment with an inhibitor of complement C5, the method comprising: determining the concentration of at least two aHUS-associated biomarker proteins in a biological fluid obtained from the subject, wherein:
 (a) the at least two aHUS-associated biomarker proteins are selected from the group consisting of: TNFR1, IL-6, proteolytic fragment Ba of complement component factor B, soluble C5b9 (sC5b9), prothrombin fragment F1+2, d-dimer, thrombomodulin, complement component C5a, β2 microglobulin (β2M), clusterin, cystatin C, fatty acid binding protein 1 (FABP-1), soluble CD40 ligand (sCD40L), vascular endothelial cell growth factor (VEGF), chemokine (C-X-C motif) ligand 9, chemokine (C-X-C motif) ligand 10, monocyte chemotactic protein-1, vascular cell adhesion molecule-1, and tissue inhibitor of metalloproteinases-1   (b) the subject has, is suspected of having, or is at risk for developing aHUS;   (c) the subject has been or is being treated with an inhibitor of complement C5; and   (d) the subject has a reduced concentration of the at least two aHUS biomarker proteins compared to the concentration measured in a sample of biological fluid of the same type obtained from the subject prior to treatment with the complement C5 inhibitor.