NZ753260B2 - Methods for reducing proteinuria in a human subject suffering from immunoglobulin a nephropathy - Google Patents

Abstract

one aspect, the invention provides methods for reducing proteinuria in a human subject suffering, or at risk of developing Immunoglobulin A Nephropathy (IgAN). The methods comprise the step of administering, to a subject in need thereof, an amount of a MASP-2 inhibitory antibody effective to inhibit MASP-2-dependent complement activation. bit MASP-2-dependent complement activation.

Description

METHODS FOR REDUCING PROTEINURIA IN A N SUBJECT SUFFERING FROM IM]VIUNOGLOBULIN A NEPHROPATHY STATEMENT REGARDING CE LISTING The sequence listing associated with this application is provided in text format in lieu of a paper copy and is hereby incorporated by reference into the specification. The name of the text file containing the sequence listing is MP_1_0269_PCT_Sequence_Listing_20171013_ST25. The text file is 136 KB, was created on October 10, 2017, and is being submitted via EFS-Web with the filing of the specification.

BACKGROUND The complement system provides an early acting mechanism to initiate, amplify and orchestrate the immune response to microbial infection and other acute insults (MK. Liszewski and JP. Atkinson, 1993, in ental Immunology, Third Edition, edited by WE. Paul, Raven Press, Ltd., New York), in humans and other vertebrates.

While complement activation provides a valuable first-line defense t ial pathogens, the activities of complement that promote a protective immune response can also represent a potential threat to the host (KR. Kalli, et al., Springer Semin. lmmunopalhol.15:417-431, 1994, BR Morgan, Eur. J. Clinical lnveslig. -228, 1994). For example, C3 and C5 proteolytic products recruit and activate neutrophils.

While indispensable for host defense, activated neutrophils are indiscriminate in their release of destructive enzymes and may cause organ damage. In addition, complement tion may cause the deposition of lytic complement components on nearby host cells as well as on microbial targets, resulting in host cell lysis.

The complement system has also been implicated in the pathogenesis of us acute and chronic disease states, including: myocardial infarction, stroke, ARDS, reperfusion injury, septic shock, capillary leakage following thermal burns, postcardiopulmonary bypass inflammation, transplant rejection, rheumatoid arthritis, le sis, myasthenia gravis, and Alzheimer's e. In almost all of these conditions, complement is not the cause but is one of l factors ed in pathogenesis. Nevertheless, complement tion may be a major ogical mechanism and represents an effective point for clinical control in many of these disease states. The growing recognition of the importance of complement-mediated tissue injury in a variety of disease states underscores the need for effective complement tory drugs. To date, Eculizumab (Solaris®), an antibody against C5, is the only complement- ing drug that has been approved for human use. Yet, C5 is one of several effector molecules located “downstream” in the complement system, and blockade of C5 does not t activation of the complement system. ore, an inhibitor of the initiation steps of complement activation would have significant advantages over a “downstream” complement inhibitor.

Currently, it is widely accepted that the complement system can be activated through three distinct pathways: the classical y, the lectin pathway, and the alternative pathway. The classical pathway is usually triggered by a X composed of host antibodies bound to a foreign particle (1'.e., an antigen) and thus requires prior exposure to an antigen for the generation of a specific antibody response. Since activation of the classical pathway depends on a prior adaptive immune response by the host, the classical pathway is part of the acquired immune system. In contrast, both the 2O lectin and alternative pathways are independent of adaptive immunity and are part of the innate immune system.

The activation of the complement system results in the sequential activation of serine protease zymogens. The first step in activation of the classical pathway is the binding of a specific recognition molecule, Clq, to antigen-bound IgG and IgM molecules. Clqis associated with the Clr and Cls serine se proenzymes as a compleX called Cl. Upon binding of Clq to an immune X, autoproteolytic cleavage of the Arg-Ile site of Clr is followed by Clr-mediated cleavage and activation of Cls, which y acquires the ability to cleave C4 and C2. C4 is cleaved into two fragments, designated C4a and C4b, and, similarly, C2 is cleaved into C2a and C2b. C4b fragments are able to form covalent bonds with adjacent hydroxyl or amino groups and generate the C3 convertase (C4b2a) through noncovalent interaction with the C2a fragment of activated C2. C3 convertase (C4b2a) activates C3 by proteolytic cleavage into C3a and C3b subcomponents leading to generation of the C5 convertase (C4b2a3b), which, by ng C5 leads to the formation of the membrane attack complex (C5b combined with C6, C7, C8 and C-9, also referred to as “MAC”) that can disrupt cellular membranes leading to cell lysis. The activated forms of C3 and C4 (C3b and C4b) are covalently ted on the foreign target surfaces, which are recognized by complement receptors on multiple phagocytes.

Independently, the first step in activation of the complement system through the lectin pathway is also the binding of specific recognition les, which is followed by the activation of associated serine protease proenzymes. However, rather than the binding of immune complexes by Clq, the recognition molecules in the lectin pathway comprise a group of carbohydrate-binding proteins (mannan-binding lectin (lVfl3L), H-f1colin, M-ficolin, L-f1colin and C-type lectin CL-l l), collectively referred to as lectins. See J. Lu et al., m. Biophys. Acta 1572:387-400, (2002); Holmskov et al., Annu. Rev. Immunol. 21:547-578 (2003); Teh et al., logy [01:225—232 (2000)).

See also J. Luet et al., Biochim Biophys Acta 1572:387-400 ; Holmskov et al, Annu Rev Immunol 21:547-578 ; Teh et al., Immunology 1012225-232 ; Hansen et al, J. Immunol ):6096-6104 (2010).

Ikeda et a1. first demonstrated that, like Clq, MBL could activate the complement system upon binding to yeast mannan-coated erythrocytes in a C4—dependent manner (Ikeda et al., J. Biol. Chem. 262:7451-7454, (1987)). MBL, a member of the collectin protein family, is a calcium-dependent lectin that binds carbohydrates with 3- and 4-hydroxy groups ed in the equatorial plane of the pyranose ring. Prominent s for MBL are thus D-mannose and N—acetyl-D-glucosamine, while carbohydrates not fitting this steric requirement have undetectable affinity for MBL (Weis et al., Nature 360:127-134, (1992)). The interaction between MBL and monovalent sugars is extremely weak, with dissociation constants typically in the single-digit millimolar range.

MBL es tight, specific binding to glycan s by avidity, i.e., by interacting simultaneously with le monosaccharide residues located in close proximity to each other (Lee et al., Archiv. Biochem. Biophys. 299:129-136, (1992)). MBL izes the carbohydrate patterns that commonly decorate microorganisms such as bacteria, yeast, parasites and certain viruses. In contrast, 1Vfl3L does not recognize D-galactose and sialic acid, the penultimate and ultimate sugars that usually decorate "mature" complex glycoconjugates present on mammalian plasma and cell surface roteins. This binding specificity is thought to promote recognition of “foreign” surfaces and help protect from “self-activation.” However, MBL does bind with high y to clusters of high-mannose "precursor" glycans on N—linked glycoproteins and glycolipids sequestered in the endoplasmic reticulum and Golgi of mammalian cells (Maynard eta1., J. Biol.

Chem. 88-3794, (1982)), Therefore, damaged cells are potential targets for lectin pathway activation via MBL binding.

The ficolins possess a different type of lectin domain than MBL, called the fibrinogen-like domain. Ficolins bind sugar residues in a Ca++-independent manner. In humans, three kinds of ficolins (L-ficolin, in and H-ficolin) have been identified.

The two serum ficolins, L-ficolin and H-ficolin, have in common a specificity for N—acetyl-D-glucosamine, however, H-ficolin also binds N—acetyl-D-galactosamine. The difference in sugar city of L-ficolin, in, CL-ll, and MBL means that the different lectins may be complementary and target different, though pping, glycoconjugates. This concept is supported by the recent report that, of the known lectins in the lectin pathway, only L-ficolin binds cally to lipoteichoic acid, a cell wall glycoconjugate found on all Gram-positive bacteria (Lynch et al., J. Immunol. 172:1198-1202, (2004)). The collectins (i.e., lVfl3L) and the ficolins bear no significant similarity in amino acid sequence. However, the two groups of proteins have similar domain organizations and, like Clq, assemble into oligomeric structures, which maximize the possibility of multisite binding. 2O The serum concentrations of MBL are highly variable in healthy populations and this is cally controlled by polymorphisms/mutations in both the promoter and coding regions of the lVfl3L gene. As an acute phase protein, the expression of MBL is further upregulated during inflammation. L-ficolin is present in serum at concentrations similar to those of lVfl3L. Therefore, the L-ficolin branch of the lectin pathway is potentially comparable to the MBL arm in th. lVfl3L and ficolins can also on as ns, which allow ytes to target lVfl3L- and ficolin-decorated surfaces (see Jack et al., J Leukoc Biol., 77(3):328-36 (2004), Matsushita and Fujita, Immunobiolog, ):490—7 (2002), Aoyagi et al., J Immunol, l74(l):418—25(2005). This opsonization requires the interaction of these proteins with phagocyte receptors an et al., J. Exp. Med. 169:1733, (1989); Matsushita et al., J. Biol. Chem. 271:2448-54, (1996)), the identity of which has not been established.

Human MBL forms a specific and ffinity interaction through its collagen-like domain with unique Clr/Cls-like serine proteases, termed MBL-associated serine ses (MASPs). To date, three MASPs have been described. First, a single enzyme "MASP" was identified and characterized as the enzyme responsible for the initiation of the complement cascade (i.e., cleaving C2 and C4) (Matsushita et al., J Exp Med 176(6):1497-1502 (1992); Ji et al., J. Immunol. [50:571-578, (1993)). It was subsequently determined that the MASP activity was, in fact, a mixture of two proteases: MASP—1 and MASP-2 (Thiel et al., Nature 386:506-510, (1997)). However, it was demonstrated that the MBL-MASP-2 complex alone is ent for complement activation (Vorup-Jensen et al., J. Immunol. 165:2093-2100, (2000)). Furthermore, only MASP-2 cleaved C2 and C4 at high rates s et al., J. Immunol. 170:1374-1382, (2003)). Therefore, MASP-2 is the protease responsible for activating C4 and C2 to generate the C3 tase, C4b2a. This is a significant difference from the Cl complex of the classical pathway, where the coordinated action of two specific serine proteases (Clr and Cls) leads to the activation of the complement system. In addition, a third novel protease, MASP-3, has been isolated (Dahl, M.R., et al., Immunity 15:127-35, 2001). MASP—l and MASP-3 are atively spliced products of the same gene.

MASPs share identical domain organizations with those of Clr and Cls, the enzymatic components of the Cl complex (Sim et al., Biochem. Soc. Trans. , (2000)). These domains include an N—terminal s/sea urchin VEGF/bone morphogenic protein (CUB) domain, an epidermal growth factor—like , a second 2O CUB domain, a tandem of complement control protein domains, and a serine protease domain. As in the Cl proteases, activation of MASP-2 occurs through cleavage of an Arg-Ile bond adjacent to the serine protease domain, which splits the enzyme into disulfide-linked A and B chains, the latter consisting of the serine se domain. lVfl3L can also associate with an alternatively sliced form of MASP-2, known as MBL-associated protein of 19 kDa (MApl9) or small associated protein (sMAP), which lacks the tic activity of MASP-2. (Stover, J. Immunol. 162:3481-90, (1999), Takahashi et al., Int. Immunol. -863, ). MAp19 comprises the first two domains of MASP-2, followed by an extra sequence of four unique amino acids. The function of MApl9 is unclear (Degn et al., J Immunol. Methods, 2011). The MASP-1 and MASP-2 genes are located on human chromosomes 3 and 1, respectively (Schwaeble et al., Immunobiology 205:455-466, (2002)).

Several lines of evidence t that there are different MBL—MASP xes and a large fraction of the MASPs in serum is not complexed with MBL (Thiel, et al., J.

Immunol. [65:878-887, ). Both H- and L-flcolin bind to all MASPs and activate the lectin complement pathway, as does MBL (Dahl et al., Immunity 15:127-35, (2001); Matsushita et a1., J. Immunol. 168:3502-3506, ). Both the lectin and classical pathways form a common C3 convertase (C4b2a) and the two pathways converge at this step.

The lectin pathway is widely thought to have a major role in host defense against infection in the naive host. Strong evidence for the ement of MBL in host defense comes from analysis of patients with decreased serum levels of functional MBL (Kilpatrick, Biochim. s. Acta 1572:401-413, ). Such patients display susceptibility to ent bacterial and fungal infections. These symptoms are usually evident early in life, during an apparent window of vulnerability as maternally derived antibody titer wanes, but before a full repertoire of antibody responses develops. This syndrome often results from mutations at several sites in the collagenous portion of lVfl3L, which interfere with proper formation of lVfl3L oligomers. However, since MBL can function as an opsonin independent of complement, it is not known to what extent the increased susceptibility to infection is due to ed complement activation.

All three pathways (i.e., the classical, lectin and alternative) have been thought to converge at C5, which is cleaved to form products with multiple proinflammatory effects, The converged pathway has been referred to as the terminal complement pathway. C5a is 2O the most potent anaphylatoxin, inducing alterations in smooth muscle and vascular tone, as well as vascular permeability. It is also a powerful chemotaxin and activator of both neutrophils and monocytes. C5a-mediated cellular tion can significantly amplify atory responses by inducing the release of multiple additional inflammatory mediators, including cytokines, hydrolytic enzymes, arachidonic acid metabolites, and reactive oxygen species. C5 cleavage leads to the formation of C5b-9, also known as the membrane attack complex (MAC). There is now strong evidence that sublytic MAC deposition may play an important role in inflammation in addition to its role as a lytic pore-forming complex.

In addition to its essential role in immune defense, the complement system butes to tissue damage in many clinical conditions. Although there is ive evidence ating both the classical and ative complement pathways in the enesis of non-infectious human diseases, the role of the lectin pathway is just beginning to be evaluated. Recent studies provide ce that activation of the lectin 2017/056386 y can be responsible for complement activation and related inflammation in ischemia/reperfusion injury. Collard et al. (2000) reported that cultured endothelial cells subjected to oxidative stress bind MBL and show deposition of C3 upon exposure to human serum (Collard et al., Am. J. Pathol. 156:1549-1556, (2000)). In addition, treatment of human sera with blocking anti-MBL monoclonal antibodies inhibited lVfl3L binding and complement activation. These findings were extended to a rat model of myocardial ischemia-reperfusion in which rats treated with a ng antibody directed against rat MBL showed significantly less myocardial damage upon occlusion of a coronary artery than rats d with a control antibody (Jordan et al., Circulation 104:1413-1418, (2001)). The molecular mechanism of MBL binding to the vascular endothelium after oxidative stress is unclear; a recent study suggests that activation of the lectin pathway after oxidative stress may be ed by MBL binding to vascular endothelial cytokeratins, and not to onjugates (Collard et al., Am. J. . 159:1045-1054, (2001)). Other s have implicated the classical and alternative pathways in the pathogenesis of ischemia/reperfusion injury and the role of the lectin pathway in this disease remains controversial (Riedermann, N.C., et al, Am. J. Pathol. 162:363-367, 2003).

Fibrosis is the formation of excessive connective tissue in an organ or tissue, commonly in response to damage or injury. A hallmark of fibrosis is the production of excessive extracellular matrix following local trauma. The normal physiological response to injury results in the deposition of connective tissue, but this initially beneficial reparative s may t and become pathological, altering the ecture and function of the tissue. At the cellular level, epithelial cells and fibroblasts proliferate and differentiate into myofibroblasts, resulting in matrix contraction, increased rigidity, ascular compression, and hypoxia. An influx of inflammatory cells, including macrophages and lymphocytes, results in ne release and amplifies the deposition of collagen, fibronectin and other molecular markers of fibrosis. Conventional therapeutic approaches have largely been targeted towards the inflammatory process of s, using corticosteroids and immunosuppressive drugs. unately, these anti- inflammatory agents have had little to no clinical effect. Currently there are no effective treatments or therapeutics for fibrosis, but both animal s and anecdotal human reports suggest that fibrotic tissue damage may be ed (Tampe and Zeisberg, Nat Rev Nephrol, Vol 10:226-237, 2014).

The kidney has a limited capacity to recover from injury. s renal pathologies result in local inflammation that causes scarring and fibrosis of renal tissue. The perpetuation of inflammatory stimuli drives tubulointerstitial inflammation and fibrosis and progressive renal functional impairment in chronic kidney disease. Its progression to end-stage renal failure is associated with significant morbidity and mortality. Since tubulointerstitial fibrosis is the common end point of multiple renal ogies, it represents a key target for therapies aimed at preventing renal failure. Risk factors (e.g., proteinuria) independent of the y renal disease contribute to the development of renal fibrosis and loss of renal excretory function by driving local inflammation, which in turn enhances disease progression.

In view of the role of fibrosis in many diseases and disorders, such as, for example, tubulointerstitial fibrosis leading to chronic kidney disease, there is a pressing need to develop therapeutically effective agents for treating diseases and conditions caused or exacerbated by fibrosis. In further view of the paucity of new and existing treatments targeting inflammatory pro-fibrotic pathways in renal disease, there is a need to develop therapeutically effective agents to treat, t, prevent and/or reverse renal fibrosis and thereby prevent ssive chronic kidney disease.

SUMMARY This y is provided to introduce a selection of concepts in a simplified form that are r bed below in the Detailed Description. This y is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject .

In a ular aspect, the present invention provides the use of a MASP-2 inhibitory monoclonal antibody, or antigen-binding fragment thereof that specifically binds to human MASP-2 and inhibits MASPdependent complement activation in an amount effective to improve renal on in the cture of a ment for treating a human subject suffering from steroid-dependent lupus nephritis (LN), wherein the composition is to be administered in an amount sufficient to improve renal function and decrease the corticosteroid dosage in said subject and wherein the MASP-2 inhibitory antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising CDR-H1, CDR-H2 and CDR-H3 of the amino acid ce set forth as SEQ ID NO:67 and a light chain variable region comprising , CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69. (followed by page 8a) In another particular aspect, the present invention provides the use of a MASP-2 inhibitory onal antibody, or antigen-binding nt thereof, comprising a heavy chain variable region comprising , CDR-H2 and CDR-H3 of the amino acid sequence set forth as SEQ ID NO:67 and a light chain variable region comprising CDR-L1, CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69 in the manufacture of a medicament for reducing proteinuria in a human subject ing from steroid-dependent Immunoglobulin A Nephropathy (IgAN) wherein the medicament is adapted for administration according to a dosage n as follows: a. the medicament comprising about 4 mg/kg of said antibody is to be administered to a subject suffering from IgAN once weekly intravenously for a treatment period of at least 12 weeks; wherein the medicament s proteinuria in said human subject.

In one aspect, the invention provides a method for ng, inhibiting, alleviating or preventing fibrosis in a mammalian subject suffering, or at risk of developing a disease or disorder caused or exacerbated by fibrosis and/or mation, comprising administering to the subject an amount of a MASP-2 inhibitory agent effective to inhibit fibrosis. In one embodiment, the MASP-2 inhibitory agent is a MASP-2 antibody or fragment thereof. In one embodiment, the MASP-2 inhibitory agent is a MASP-2 monoclonal antibody, or fragment thereof that specifically binds to a portion of SEQ ID NO:6. In one embodiment, the MASP-2 inhibitory agent selectively inhibits lectin pathway complement activation without substantially inhibiting C1q-dependent complement activation. In one embodiment, the subject is ing from a disease or [FOLLOWED BY PAGE 9] - 8a - disorder caused by or exacerbated by at least one of (i) fibrosis and/or inflammation associated with an ischemia reperfusion , (ii) renal fibrosis and/or renal inflammation (e.g., tubulointerstitial fibrosis, chronic kidney disease, chronic renal failure, glomerular e (e.g., focal segmental glomerulosclerosis), an immune x disorder (e.g., IgA nephropathy, membraneous nephropathy), lupus nephritis, nephrotic me, diabetic nephropathy, tubulointerstitial damage and glomerulonepthlitis (e.g., C3 glomerulopathy), (iii) pulmonary fibrosis and/or inflammation (e.g., chronic obstructive pulmonary disease, cystic fibrosis, pulmonary fibrosis ated with scleroderma, bronchiectasis and pulmonary hypertension), (iv) hepatic s and/or inflammation (e.g., cirrhosis, nonalcoholic fatty liver disease (steatohepatitis)), liver fibrosis secondary to alcohol abuse, liver fibrosis secondary to acute or chronic hepatitis, y disease and toxic liver injury (e.g., hepatotoxicity due to drug-induced liver damage induced by acetaminophen or other drug), (v) cardiac fibrosis and/or inflammation (e.g., cardiac fibrosis, myocardial infarction, valvular fibrosis, atrial fibrosis, endomyocardial fibrosis hmogenic right ventricular cardiomyopathy , (vi) vascular fibrosis (e. g., vascular disease, an atherosclerotic vascular disease, ar stenosis, restenosis, vasculitis, phlebitis, deep vein thrombosis and abdominal aortic aneurysm), (vii) fibrosis of the skin (e.g., ive wound healing, scleroderma, systemic sclerosis, s, connective tissue diseases, scarring, and hypertrophic scars), (viii) fibrosis of the joints (e.g., arthrofibrosis), (ix) fibrosis of the central nervous system (e.g., stroke, traumatic brain injury and spinal cord injury), (x) fibrosis of the digestive system (e.g., Crohn’s disease, pancreatic fibrosis and ulcerative colitis), (xi) ocular fibrosis (e.g., anterior sular cataract, posterior capsule opacification, r degeneration, and retinal and vitreal retinopathy), (xii) fibrosis of musculoskeletal soft- tissue structures (e.g., adhesive capsulitis, Dupuytren’s cture and myelofibrosis), (xiii) fibrosis of the reproductive organs (e.g., endometriosis and Peyronie’s disease), (xiv) a chronic infectious disease that causes fibrosis and/or inflammation (e.g., alpha virus, Hepatitis A, Hepatitis B, Hepatitis C, tuberculosis, HIV and influenza), (xv) an autoimmune disease that causes fibrosis and/or inflammation (e.g., scleroderrna and systemic lupus matosus (SLE), (xvi) scarring ated with trauma (e.g., wherein the scarring associated with trauma is selected from the group consisting of surgical complications (e,g., surgical adhesions wherein scar tissue can form between internal organs causing contracture, pain and can cause infertility), chemotherapeutic drug-induced fibrosis, radiation-induced fibrosis and scarring associated with burns), or (xvii) organ transplant, breast fibrosis, muscle fibrosis, retroperitoneal fibrosis, thyroid fibrosis, lymph node fibrosis, bladder fibrosis and pleural fibrosis.

In another aspect, the present ion provides a method for treating, inhibiting, alleviating or ting renal fibrosis in a mammalian subject suffering, or at risk of developing a disease or disorder caused or exacerbated by renal fibrosis and/or inflammation, comprising administering to the subject an amount of a MASP—Z inhibitory agent effective to inhibit renal fibrosis. In one embodiment, the MASP-2 inhibitory agent is a MASP—2 antibody or fragment thereof. In one embodiment, the MASP-2 inhibitory agent is a MASP-2 onal antibody, or nt thereof that specifically binds to a n of SEQ ID NO:6. In one embodiment, the MASP-Z antibody or fragment thereof specifically binds to a polypeptide comprising SEQ ID N06 with an affinity of at least times greater than it binds to a different antigen in the complement system. In one embodiment, the antibody or fragment thereof is selected from the group consisting of a recombinant antibody, an antibody having reduced effector function, a chimeric antibody, a zed antibody and a human antibody. In one embodiment, the MASP-2 inhibitory agent selectively inhibits lectin pathway complement tion without substantially ting Clq-dependent ment activation. In one embodiment, the MASP-Z inhibitory agent is administered subcutaneously, intraperitoneally, intra- muscularly, arterially, intravenously, or as an inhalant. In one embodiment, the MASP-Z inhibitory agent is administered in an amount effective to inhibit tubulointerstitial fibrosis. In one embodiment, the MASP-Z inhibitory agent is administered in an amount effective to reduce, delay or eliminate the need for dialysis in the subject. In one embodiment, the subject is suffering from a renal disease or disorder selected from the group ting of chronic kidney disease, chronic renal failure, glomerular e (e.g., focal segmental glomerulosclerosis), an immune x disorder (e.g., IgA nephropathy, membraneous nephropathy), lupus nephritis, tic syndrome, diabetic pathy, tubulointerstitial damage and glomerulonepthritis (e.g., C3 glomerulopathy). In one embodiment, the subject is suffering from proteinuria and the MASP-2 inhibitory agent is administered in an amount effective to reduce proteinuria in the subject. In one embodiment, the MASP-2 tory agent is administered in an amount and for a time effective to achieve at least a 20 percent reduction (e.g., at least a percent reduction, or at least a 40 percent reduction, or at least a 50 percent reduction) in 24-hour urine protein excretion as compared to baseline 24-hour urine protein excretion in the subject prior to treatment. In one embodiment, the t is suffering from a renal e or disorder associated with proteinuria selected from the group consisting of nephrotic syndrome, pre-eclampsia, sia, toxic lesions of kidneys, amyloidosis, collagen vascular diseases (e.g., systemic lupus erythematosus), dehydration, ular diseases (e.g. membranous glomerulonephritis, focal segmental glomerulonephritis, C3 glomerulopathy, minimal change disease, lipoid nephrosis), strenuous exercise, stress, benign orthostatis (postural) proteinuria, focal tal glomerulosclerosis, IgA nephropathy (i.e., Berger’s disease), IgM nephropathy, membranoproliferative glomerulonephritis, membranous nephropathy, minimal change disease, sarcoidosis, Alport’s syndrome, diabetes mellitus (diabetic nephropathy), drug- induced toxicity (e.g., NSAIDS, nicotine, penicillamine, lithium carbonate, gold and other heavy metals, ACE inhibitors, antibiotics (e. g., adriamycin) or opiates (e.g. heroin) or other nephrotoxins); Fabry’s disease, infections (e.g., HIV, syphilis, hepatitis A, B or C, poststreptococcal ion, urinary schistosomiasis), aminoaciduria, Fanconi syndrome, hypertensive sclerosis, interstitial nephritis, sickle cell disease, hemoglobinuria, multiple myeloma, myoglobinuria, organ rejection (e.g., kidney lant rejection), ebola hagic fever, Nail patella syndrome, familial mediterranean fever, HELLP syndrome, systemic lupus erythematosus, Wegener’s granulomatosis, Rheumatoid arthritis, Glycogen storage disease type 1, Goodpasture’s syndrome, Henoch-Schénlein purpura, urinary tract infection which has spread to the kidneys, SjOgren’s me and post-infections glomerulonepthritis. In one ment, the subject is suffering from IgA nephropathy. In one embodiment, the t is ing from membranous nephropathy.

In another aspect, the present invention provides a method of preventing or reducing renal damage in a subject suffering from a disease or condition associated with proteinuria comprising administering an amount of a MASP-2 tory agent effective to reduce or prevent proteinurea in the subject. In one embodiment, the MASP-2 inhibitory agent is a MASP-Z antibody or fragment thereof. In one embodiment, the MASP-2 inhibitory agent is a MASP-Z monoclonal antibody or fragment thereof that specifically binds to a portion of SEQ ID NO:6. In one embodiment, the MASP-Z inhibitory agent selectively inhibits lectin pathway complement activation t substantially ting Clq-dependent complement tion. In one embodiment, the disease or condition ated with proteinuria is selected from the group consisting of nephrotic syndrome, pre-eclampsia, sia, toxic lesions of kidneys, amyloidosis, collagen vascular es (e.g., systemic lupus erythematosus), dehydration, glomerular diseases (e.g. nous ulonephritis, focal segmental glomerulonephritis, C3 glomerulopathy, minimal change disease, lipoid nephrosis), ous exercise, stress, benign orthostatis ral) proteinuria, focal segmental glomerulosclerosis, IgA nephropathy (i.e., Berger’s disease), IgM nephropathy, membranoproliferative glomerulonephritis, membranous nephropathy, l change disease, sarcoidosis, Alport’s syndrome, diabetes mellitus (diabetic nephropathy), drug-induced toxicity (e.g., NSAIDS, nicotine, penicillamine, m carbonate, gold and other heavy metals, ACE inhibitors, antibiotics (e.g., adriamycin) or opiates (e.g. heroin)); Fabry’s disease, infections (e.g., HIV, syphilis, hepatitis A, B or C, poststreptococcal infection, urinary schistosomiasis); aminoaciduria, Fanconi syndrome, hypertensive nephrosclerosis, interstitial nephritis, sickle cell disease, hemoglobinuria, multiple myeloma, myoglobinuria, organ rejection (e.g., kidney transplant rejection), ebola hemorrhagic fever, Nail patella syndrome, familial rranean fever, HELLP syndrome, systemic lupus erythematosus, Wegener’s granulomatosis, toid arthritis, Glycogen storage disease type 1, Goodpasture’s syndrome, Henoch-Schonlein purpura, urinary tract infection which has spread to the kidneys, SjOgren’s syndrome and post-infections glomerulonepthlitis. In one embodiment, the MASP-2 tory agent is administered in an amount and for a time effective to achieve at least a 20 percent reduction (e.g., at least a 30 t ion, or at least a 40 t reduction, or at least a 50 percent reduction) in 24-hour urine protein excretion as compared to baseline 24-hour urine protein excretion in the subject prior to treatment.

In another aspect, the present invention provides a method of inhibiting the progression of chronic kidney disease, comprising administering an amount of a MASP-2 inhibitory agent effective to reduce or prevent renal fibrosis, e.g., tubulointerstitial fibrosis, in a subject in need thereof. In one embodiment, the MASP-2 tory agent is a MASP-2 dy or fragment f. In one embodiment, the MASP-2 inhibitory agent is a MASP-2 monoclonal antibody, or fragment thereof that specifically binds to a portion of SEQ ID NO:6. In one embodiment, the MASP-2 inhibitory agent selectively inhibits lectin pathway complement activation Without substantially inhibiting Clq- dependent complement activation. In one embodiment, the subject in need thereof exhibits nuria prior to administration of the MASP-2 inhibitory agent and administration of the MASP-Z inhibitory agent decreases proteinuria in the subject. In one embodiment, the MASP-Z inhibitory agent is administered in an amount and for a time effective to achieve at least a 20 percent reduction (e.g., at least a 30 percent reduction, or at least a 40 percent ion, or at least a 50 percent reduction) in 24-hour urine n excretion as compared to baseline 24-hour urine protein excretion in the subject prior to treatment. In one embodiment, the MASP-Z inhibitory agent is administered in an amount effective to reduce, delay or eliminate the need for dialysis in the subject.

In another aspect, the invention es a method of protecting a kidney from renal injury in a subject that has undergone, is undergoing, or will undergo ent with one or more nephrotoxic agents, comprising stering an amount of a MASP-2 inhibitory agent effective to prevent or ameliorate nduced nephropathy. In one embodiment, the MASP-2 inhibitory agent is a MASP-2 antibody or fragment thereof. In one embodiment, the MASP-2 tory agent is a MASP-2 monoclonal antibody or fragment thereof that specifically binds to a portion of SEQ ID NO:6. In one ment, the MASP-Z inhibitory agent selectively inhibits lectin pathway complement tion t substantially inhibiting Clq—dependent complement activation.

In r aspect, the invention provides a method of treating a human t ing from Immunoglobulin A Nephropathy (IgAN) comprising administering to the subject a composition comprising an amount of a MASP-2 inhibitory antibody, or antigen-binding fragment thereof, effective to inhibit MASP-Z-dependent complement activation. In one embodiment, the subject is suffering from steroid-dependent IgAN. In one embodiment, the MASP-2 inhibitory antibody is a monoclonal antibody, or fragment thereof that specifically binds to human MASP-Z. In one embodiment, the antibody or fragment thereof is selected from the group consisting of a recombinant antibody, an antibody having reduced effector function, a chimeric dy, a zed antibody, and a human antibody. In one embodiment, the MASP-2 inhibitory antibody does not substantially inhibit the classical pathway. In one embodiment, the MASP-2 inhibitory antibody inhibits C3b deposition in 90% human serum with an IC50 of 30 nM or less. In one embodiment, the method further comprises identifying a human subject having steroid—dependent IgAN prior to the step of administering to the subject a composition sing an amount of a MASP-2 inhibitory antibody, or antigen-binding fragment thereof, effective to improve renal function. In one embodiment, the MASP-2 inhibitory antibody or antigen-binding nt thereof is administered in an amount ive to improve renal function. In one embodiment, the MASP-2 tory antibody or antigen-binding nt thereof is administered in an amount effective and for a time sufficient to achieve at least a 20 percent reduction in 24-hour urine protein excretion as compared to baseline 24-hour urine protein excretion in the subject prior to treatment. In one embodiment, the composition is administered in an amount sufficient to improve renal on and decrease the corticosteroid dosage in said subject. In one embodiment, the MASP-2 inhibitory antibody or antigen-binding fragment thereof ses a heavy chain variable region comprising CDRH1 , CDR-H2 and CDR-H3 of the amino acid sequence set forth as SEQ ID NO:67 and a light chain le region comprising CDR-L1, CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69.

In another aspect, the invention provides a method of treating a human subject suffering from membranous nephropathy (MN) comprising administering to the subject a composition sing an amount of a MASP-2 tory antibody, or antigen-binding fragment thereof, effective to inhibit MASPdependent complement activation. In one embodiment, the subject is ing from steroid-dependent MN. In one embodiment, the MASP-2 inhibitory antibody is a monoclonal antibody, or fragment thereof that specifically binds to human MASP-2. In one embodiment, the MASP-2 inhibitory antibody or antigenbinding fragment thereof is administered in an amount effective to improve renal function. In one embodiment, the MASP-2 inhibitory antibody or antigen-binding fragment thereof is administered in an amount effective and for a time sufficient to achieve at least a 20 percent ion in 24-hour urine protein excretion as ed to baseline 24-hour urine protein excretion in the subject prior to treatment. In one embodiment, the ition is administered in an amount sufficient to improve renal on and decrease the corticosteroid dosage in said subject. In one embodiment, the MASP-2 inhibitory antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising CDRH1 , CDR-H2 and CDR-H3 of the amino acid sequence set forth as SEQ ID NO:67 and a light chain variable region comprising CDR-L1, CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69.

In another aspect, the invention provides a method of treating a human subject suffering from Lupus tis (LN) comprising administering to the subject a composition comprising an amount of a MASP-2 inhibitory antibody, or n-binding fragment thereof, effective to t MASPdependent complement activation. In one embodiment, the subject is suffering from steroid-dependent LN. In one embodiment, the MASP-2 inhibitory antibody is a monoclonal antibody, or fragment thereof that specifically binds to human MASP-2. In one embodiment, the MASP-2 inhibitory antibody or n-binding fragment thereof is administered in an amount effective to improve renal function. In one ment, the MASP-2 inhibitory antibody or n-binding fragment thereof is administered in an amount effective and for a time sufficient to achieve at least a 20 percent reduction in 24-hour urine protein ion as compared to ne 24-hour urine protein excretion in the subject prior to treatment. In one embodiment, the composition is administered in an amount sufficient to improve renal function and decrease the corticosteroid dosage in said subject. In one embodiment, the MASP-2 tory antibody or antigen-binding fragment thereof comprises a heavy chain variable region comprising CDR-H1, CDR-H2 and CDR-H3 of the amino acid ce set forth as SEQ ID NO:67 and a light chain variable region comprising CDR-L1, CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69.

In another , the invention provides a method of reducing proteinuria in a human subject suffering from IgAN comprising administering to the subject a MASP-2 inhibitory antibody, or antigen-binding fragment thereof, comprising a heavy chain variable region comprising CDR-H1, CDR-H2 and CDR-H3 of the amino acid sequence set forth as SEQ ID NO:67 and a light chain le region comprising CDR-L1, CDR-L2 and CDR-L3 of the amino acid sequence set forth as SEQ ID NO:69 according to a dosage regimen as follows: a. administering about 4 mg/kg (i.e., from 3.6 mg/kg to 4.4 mg/kg) of said antibody to a subject suffering from IgAN once weekly intravenously for a treatment period of at least 12 weeks; or b. administering from about 180 mg to about 725 mg (i.e., from 162 mg to 797 mg) of said antibody to a t suffering from IgAN once weekly intravenously for a treatment period of at least 12 weeks, wherein the method reduces proteinuria in said human subject.

W0 2018.107170] DESCRIPTION OF THE DRAWINGS The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following ed description, when taken in conjunction with the accompanying drawings, wherein: FIGURE 1 is a diagram illustrating the genomic structure of human ;