Potent, aggregate-selective Anti-aβ antibodies and uses thereof

Abstract

The invention provides binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, nucleic acids comprising the inventive binding agents, vectors and cells comprising the inventive nucleic acids, and pharmaceutical compositions thereof. The invention also provides methods for treating or preventing a disease, disorder, or condition, in particular, Alzheimer's disease, in a mammal, by administering the binding agents or compositions thereof. The invention further provides methods for inducing clearance of an aggregated form of amyloid-beta (Aβ) peptide in a mammal, comprising administering the inventive binding agents and pharmaceutical compositions described herein.

Description

Leydig 774215 1 POTENT, AGGREGATE-SELECTIVE ANTI-Aβ ANTIBODIES AND USES THEREOF CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 681,564 filed on August 9, 2024, the entire disclosure of which is hereby incorporated by reference. INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ELECTRONICALLY

[0002] Incorporated by reference in its entirety herein is a computer-readable nucleotide / amino acid sequence listing submitted concurrently herewith and identified as follows: One 303,554 Byte Extensible Markup Language (xml) file named "774215_SequenceListing.xml," created on August 9, 2025. BACKGROUND OF THE INVENTION

[0003] Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that represents the most common cause of dementia in aged individuals. It is characterized by a gradual decline in cognitive function, memory loss, and behavioral changes. The prevalence of AD increases throughout life, affecting approximately 13.2% of individuals age 75-84 and 33.4% over age 85 (Alzheimer's Association, “2024 Alzheimer's disease facts and figures,” Alzheimer's & Dementia, 20(5):3708-3821 (April 2024)). The neuropathological hallmarks of AD include extracellular amyloid plaques, intracellular neurofibrillary tangles, and significant loss of synapses and neurons.

[0004] The primary component of amyloid plaques is the amyloid-beta (Aβ) peptide, which is derived from the amyloid precursor protein (APP) through sequential cleavage by beta-secretase and gamma-secretase. Mutations in APP or PSEN1 and PSEN2, proteins involved in APP processing, lead to increased Aβ production and cause familial Alzheimer's Disease (FAD), an inherited form of AD (Levy-Lahad, et al., “Candidate gene for the chromosome 1 familial Alzheimer's disease locus,” Science, 269(5226):973-977 (1995); Goate, et al., “Segregation of a missense mutation in the amyloid precursor protein gene with familial Alzheimer's disease,” Nature, 349(6311):704-706 (1991); and Sherrington, et al., “Cloning of a gene bearing missense mutations in early-onset familial Alzheimer's disease,”Leydig 774215 2 Nature, 375(6534):754-760 (1995)). Although FAD only accounts for a small portion of AD cases, the central role Aβ plays in the pathogenesis of AD has led to formation of the amyloid cascade hypothesis, which posits that the accumulation and aggregation of Aβ peptides plays a central role in the pathogenesis of both FAD and the more common sporadic AD (Karran, et al., “The amyloid cascade hypothesis for Alzheimer's disease: an appraisal for the development of therapeutics,” Nature Reviews Drug Discovery, 10(9):698-712 (2011)).

[0005] Aβ exists in several isoforms and aggregation states, with monomeric Aβ being thought to serve important biological functions with minimal neurotoxicity (Jeong, et al., “Physiological roles of monomeric amyloid-β and implications for Alzheimer’s disease therapeutics,” Experimental Neurobiology, 31(2):65 (2022)). Aβ aggregates exist in different sizes including soluble oligomers, soluble protofibrils, and mature fibrils (Benilova et al., “The toxic Aβ oligomer and Alzheimer's disease: an emperor in need of clothes,” Nature Neuroscience, 15(3):349-57 (January 2012)). These aggregated forms of Aβ are neurotoxic and disrupt synaptic function, leading to the cognitive deficits observed in AD patients. Soluble Aβ (sAβ) aggregates are particularly toxic, causing synaptic dysfunction and neuronal death (Hartley, et al., “Protofibrillar intermediates of amyloid β-protein induce acute electrophysiological changes and progressive neurotoxicity in cortical neurons,” Journal of Neuroscience, 19(20):8876-8884 (1999)). Fibrils, though less toxic, contribute to the structural core of amyloid plaques and constitute the majority of the total brain amyloid burden in AD (Mucke, et al., “Neurotoxicity of amyloid β-protein: synaptic and network dysfunction,” Cold Spring Harbor perspectives in medicine, 2(7):a006338 (2012)).

[0006] Given the central role of Aβ aggregation in AD, therapeutic strategies have focused on targeting Aβ to prevent its aggregation, promote its clearance, or neutralize its toxic effects. Both prevention of aggregation and facilitation of clearance are important. They may serve as two phases of treatment – first clearance of plaque and then prevention of new plaque from forming. One promising approach is the development of antibodies that target Aβ. However, some existing antibodies have targeted monomeric Aβ or bind broadly across different forms of Aβ, which may cause non-pathogenic forms of Aβ to compete with pathogenic forms, limiting antibody efficacy (Goure, et al., “Targeting the proper amyloid- beta neuronal toxins: a path forward for Alzheimer’s disease immunotherapeutics,” Alzheimer's Research & Therapy, 6:1-15 (2014); Sperling, et al., “Trial of solanezumab in preclinical Alzheimer’s disease,” New England Journal of Medicine, 389(12):1096-1107 (2023); and Tolar, et al., “Aducanumab, gantenerumab, BAN2401, and ALZ-801—the firstLeydig 774215 3 wave of amyloid-targeting drugs for Alzheimer’s disease with potential for near term approval,” Alzheimer's Research & Therapy, 12(1):95 (2020)).

[0007] Recent advances have highlighted the need for antibodies with high selectivity for aggregated forms of Aβ, such as sAβ aggregates and fibrils, while minimizing binding to monomeric Aβ. Such selectivity may improve the therapeutic profile of these antibodies. Selective targeting of aggregated Aβ forms is advantageous because it directly addresses the pathogenic species responsible for neurotoxicity and plaque formation.

[0008] To that end, monoclonal antibodies such as Lecanemab and Donanemab, which selectively target aggregated forms of Aβ or amyloid aggregates that contain pyroglutamate (pGlu) modified Aβ, have shown promising results in clinical trials, leading to FDA approval of both molecules. These antibodies have been effective in slowing cognitive decline and reducing amyloid plaque burden in patients with AD, validating the important therapeutic potential of targeting aggregated Aβ with slowing of cognitive decline by 27-35% after 18 months (Van Dyck, et al., “Lecanemab in early Alzheimer’s disease,” New England Journal of Medicine, 388(1):9-21 (2023) and Sims, et al., “Donanemab in early symptomatic Alzheimer disease: the TRAILBLAZER-ALZ 2 randomized clinical trial,” JAMA, 330(6):512-527 (2023)).

[0009] However, there remains an ongoing need in the art for potent binding agents that selectively target aggregated forms of amyloid-beta (Aβ) peptides and can be used for the diagnosis, prevention, and treatment of Alzheimer's disease and other disorders characterized by Aβ aggregation. The invention provides such compounds and approaches to effectively deliver them across the blood brain barrier (BBB) to reach amyloid plaques in the brain. The binding agents of the invention also can be used to induce clearance of pathogenic Aβ aggregates. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein. BRIEF SUMMARY OF THE INVENTION

[0010] The invention provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide and an immunoglobulin light chain variable region polypeptide, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22 and 59, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23-42Leydig 774215 4 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62 and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS, WAS, KVF, SEQ ID NOs: 83-102 and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122 and 275.

[0011] The invention also provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317 or at least the CDRs thereof.

[0012] The invention further provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317.

[0013] The invention also provides a nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein.

[0014] The invention further provides a vector comprising a nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein.

[0015] The invention also provides an isolated cell comprising any one of the described nucleic acids or the described vectors.

[0016] The invention also provides a method of providing the binding agent targeted to the aggregated form of an amyloid-beta (Aβ) peptide described herein, the method comprising expressing in a cell in vitro one or more nucleic acids encoding the immunoglobulin heavy and light chain polypeptides thereof.Leydig 774215 5

[0017] The invention also provides a composition comprising any one of the described binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, the described nucleic acids, or the described vectors, and a pharmaceutically acceptable carrier. In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein is conjugated to a blood-brain barrier (BBB) shuttle moiety. In some embodiments, the composition is formulated for nasal administration, intravenous injection, subcutaneous injection, or intraperitoneal injection. In some embodiments, the composition is formulated for intravenous injection. In some embodiments, the composition is formulated for subcutaneous injection.

[0018] The invention further provides a method for treating or preventing a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance, the method comprising administering any one of the described binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the described compositions, to the mammal.

[0019] The invention also provides a method for inducing clearance of an aggregated form of amyloid-beta (Aβ) peptide in a mammal, the method comprising administering any one of the described binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the described composition, to the mammal.

[0020] The invention also provides a hybridoma or cell line that expresses any one of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein.

[0021] The invention further provides a method of diagnosing Alzheimer’s disease in a mammal, the method comprising: (1) taking a biological sample of the mammal, (2) contacting the sample with the binding agents targeted to the aggregated form of amyloid- beta (Aβ) peptide described herein, (3) measuring the concentration of complexes formed of the sample and the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein, and (4) comparing the concentration of complexes to a reference value. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0022] FIGs.1A and 1B are graphs showing the results of size exclusion chromatography size exclusion chromatography (SEC) high performance liquid chromatography (HPLC) inLeydig 774215 6 milli-absorbance units (mAU) vs. time in minutes for purified human sAβ 1-42 aggregates (FIG.1A) and purified Aβ 1-40 monomer (FIG.1B).

[0023] FIG.2 is a flow chart showing an antibody discovery method used for isolation and initial characterization of antibodies described herein.

[0024] FIGs.3A-3C are graphs showing the results of direct ELISA on soluble Aβ (sAβ) aggregate-coated plates in OD 450nm vs. antibody concentration in µg / mL over 5 rounds of screening. The antibodies 1A3, 1A5, 1G8, 1H2, 1B9, 2D8, and 2A10 were tested in rounds 1 and 2 (FIG.3A), the antibodies 3C6, 3B8, 3E8, 3E10, and 3E2 were tested in round 3 (FIG. 3B), the antibodies 4D11, 4A10, 4B2, 5H1, 4E1, and 4C10 were tested in rounds 4 and 5 (FIG.3C), and Lecanemab (solid circle with dashed line) was used as a reference antibody in all rounds.

[0025] FIGs.4A-4C are graphs showing results of direct ELISA with plates coated with soluble Aβ (sAβ) aggregate (top graph) or Aβ monomer (bottom graph) in OD 450nm vs. antibody concentration in µg / mL over 4 rounds of screening. The antibodies 1A3, 1G8, 1A5, 1B9, 1H2, 2A10, and 2D8 were tested in rounds 1 and 2 (FIG.4A), the antibodies 3E8, 3B8, 3C6, 3E10, and 3E2 were tested in round 3 (FIG.4B), the antibodies H1G8_K1A3, 4A10_M1, 4D11, 4A10, 4B2, and 4E1 were tested in round 4 (FIG.4C), and Lecanemab (solid circle with dashed line) and H2731 (empty circle with dashed line) were used as reference antibodies.

[0026] FIGs.5A-5I are graphs showing the results of competition ELISA as the percent of uncompeted OD vs. amyloid beta (Abeta) concentration in µM as either the soluble Aβ aggregate (sAβ Agg, line with solid circles), 1-40 monomer (1-40 Mono, dashed line with empty squares), or 1-28 monomer (1-28 Mono, dotted line with empty circles) for Lecanemab (FIG.5A), H2731 (FIG.5B), 3B8 (FIG.5C), 4B2 (FIG.5D), 3E8 (FIG.5E), 4D11 (FIG.5F), 1G8 (FIG.5G), 4A10_M1 (FIG.5H), and H1G8_K1A3 (FIG.5I). The vertical dotted lines at 133 picomolar Abeta concentration represent the presumed lower limit of detection at which point the number of Aβ peptides equals the number of antibody binding sites.

[0027] FIGs.6A-6H are graphs showing the association and dissociation of anti-Aβ antibodies as concentration (nM) vs. time in seconds (s) for Lecanemab (FIG.6A), 1G8 (FIG. 6B), 3E8 (FIG.6C), H1G8-K1A3 (FIG.6D), 4A10_M1 (FIG.6E), 4B2 (FIG.6F), 3B8 (FIG. 6G), and H2731 (FIG.6H).Leydig 774215 7

[0028] FIGs.7A and 7B are immunofluorescent micrographs of unfixed, frozen brain sections from 7.5-month-old female mice carrying humanized APP with three FAD- associated mutations (APP-SAA) stained for Aβ plaques by treatment with Lecanemab (A), H2731 (B), 1G8 (C), or 3B8 (D) (FIG.7A), or 3E8 (E), 4A10_M1 (F), 4B2 (G), or H1G5_K1A3 (H) (FIG.7B). The scale bars are 50 μm.

[0029] FIGs.8A and 8B are immunofluorescent micrographs of unfixed, frozen brain sections from human donors with AD (Braak stage IV, 10 μm thick) stained for Aβ plaques by treatment with Lecanemab (A), H2731 (B), 1G8 (C), or 3B8 (D) (FIG.8A), or 4B2 (E), or the pan-anti-amyloid antibody control 6E10 (F) (FIG.8B). The scale bars are 50 μm.

[0030] FIG.9 is a graph showing in vitro phagocytosis of sAβ aggregates by iPSC- derived microglia-like cells as normalized mean fluorescence intensity (MFI) vs. concentration (nM) of the antibodies Lecanemab, H2731, 1A3, 3E8, 1G8, 4B2, 3B8, or 1B9.

[0031] FIG.10 is a set of fluorescent micrographs showing amyloid plaques stained using the anti-APP antibody 6E10 or Amylo-glo on unfixed APP-SAA brain sections following treatment with Lecanemab, H2731, IgG, H1G8-K1A3, 4A10_M1, 3B8, 3E8, 4B2, or 1G8 antibodies prior to ex vivo phagocytosis by iPSC-derived microglia-like cells.

[0032] FIGs.11A-11C are graphs showing the results of direct ELISA on soluble Aβ (sAβ) aggregate-coated plates with humanized anti-Aβ antibodies (solid lines) compared with parental, non-humanized mouse (mu) antibodies (dashed lines), as OD 450 nM vs. amyloid beta (Ab) concentration in µg / mL. The 1G8 parental non-humanized mouse antibody (1G8_mu) and humanized variants are shown in FIG.11A, the 3B8 parental non-humanized mouse antibody (3B8_mu) and humanized variants are shown in FIG.11B, and the 4B2 parental non-humanized mouse antibody (4B2_mu) and humanized variants are shown in FIG.11C.

[0033] FIGs.12A-12D are graphs showing the results of direct ELISA on soluble Aβ (sAβ) aggregate-coated plates (FIGs.12A and 12B) and competition ELISA with Aβ monomer (FIGs.12C and 12D) for mutants to the 1G8_V3 antibody in which mutant residues were combined using lineage-based rational design (RD) (mutant sequences shown in solid lines) and compared with parental 1G8_V3 (dashed lines with black circles).

[0034] FIGs.13A-13D are graphs showing the results of direct ELISA on soluble Aβ (sAβ) aggregate-coated plates (FIGs.13A and 13B) and competition ELISA with Aβ monomer (FIGs 13C and 13D) for mutants to the 1G8_V3 antibody in which mutant residuesLeydig 774215 8 were discovered using a look-through-mutagenesis (mutant sequences shown in solid lines) and compared with parental 1G8_V3 (dashed lines with black circles).

[0035] FIGs.14A and 14B are graphs showing the results of direct ELISA on soluble Aβ (sAβ) aggregate-coated plates with a 24-hour dissociation step before development (FIG. 14A) and competition ELISA with Aβ monomer (FIG.14B) for antibody 1B9 displayed in a multivalent format (MV).

[0036] FIG.15 is a graph showing the brain-to-plasma ratios following intravenous injection of 1G8_V3 compared to 1G8_V3 connected to a BBB shuttle. These molecules were injected into mice expressing human transferrin receptor (TfR) extracellular domain and showed increased central nervous system (CNS) delivery. DETAILED DESCRIPTION OF THE INVENTION

[0037] The invention provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide and an immunoglobulin light chain variable region polypeptide, wherein the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22 and 59, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23-42 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62 and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS, WAS, KVF, or any one of SEQ ID NOs: 83-102 and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122 and 275.

[0038] The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of the invention binds to any aggregated form of amyloid-beta (Aβ) peptide homolog or paralog. As used herein, the term "aggregated form of amyloid-beta (Aβ) peptide" refers to any non- monomeric assembly comprising two or more Aβ peptide molecules that are directly or indirectly associated with each other. These assemblies may contain multiple Aβ peptides directly in contact via non-covalent interactions and / or one or more covalent bonds. Assemblies may also contain Aβ peptides indirectly associated between non-Aβ molecules (e.g., proteins, lipids, metal ions, carbohydrates, or other factors). Aggregate componentsLeydig 774215 9 may be associated through non-covalent interactions and / or one or more covalent bonds. In embodiments, the aggregated form of Aβ peptide includes, but is not limited to, soluble oligomers, soluble protofibrils, and mature fibrils. In embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide binds the aggregated form of amyloid-beta (Aβ) peptide. In other embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide binds the human aggregated form of amyloid- beta (Aβ) 1-42 peptide: DAEFRHDSGYEVHHQKLVFFAEDVGSNKGAIIGLMVGGVVIA (SEQ ID NO: 323). In other embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide binds the human aggregated form of amyloid-beta (Aβ) 1-40 peptide: DAEFRHDSGYEVHHQKLVFFAEDVGSNKGAIIGLMVGGVV (SEQ ID NO: 324). In other embodiments, the binding agent targeted to the aggregated form of amyloid- beta (Aβ) peptide binds the human aggregated form of amyloid-beta (Aβ) 1-28 peptide: DAEFRHDSGYEVHHQKLVFFAEDVGSNK (SEQ ID NO: 325). In some embodiments, the aggregated form of amyloid-beta (Aβ) peptide comprises at least about 70%, about 75%, about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more sequence identity to SEQ ID NO: 323. In other embodiments, the aggregated form of amyloid-beta (Aβ) peptide comprises at least about 70%, about 75%, about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more sequence identity to SEQ ID NO: 324. In some embodiments, the aggregated form of amyloid-beta (Aβ) peptide comprises at least about 70%, about 75%, about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more sequence identity to SEQ ID NO: 325.

[0039] The binding properties or characteristics of an antigen-binding agent can be observed, measured, and / or assessed using standard techniques including, but not limited to, ELISA, competitive ELISA, surface plasmon resonance analysis (BIACORE™), or KINEXA™, in vitro or in vivo neutralization assays, receptor-ligand binding assays, and immunohistochemistry assays.

[0040] As used herein, the terms “immunoglobulin heavy chain variable region polypeptide” (“Ig heavy chain variable region polypeptide”) and “immunoglobulin light chain variable region polypeptide” (“Ig light chain variable region polypeptide”) refer to the polypeptides that together form an antigen binding site. Each of the Ig heavy and light chain variable regions are polypeptides comprising three complementarity determining regionsLeydig 774215 10 (CDR1, CDR2, and CDR3) connected by framework regions. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of the invention can be any of a variety of types of binding agents known in the art that comprise Ig heavy and light chains.

[0041] The CDRs of a given heavy or light chain Ig sequence can be determined in accordance with any of the various known Ig numbering schemes, such as Kabat, Chothia, Martin (Enhanced Chothia), IMGT, AbM or AHo (see, e.g., Kabat, et al., “Sequences of Proteins of Immunological Interest,” U.S. Department of Health and Human Services, NIH (1991); Chothia, et al., “Canonical Structures for the Hypervariable Regions of Immunoglobulins,” J. Mol. Biol., 196:901-917 (1987); Al-Lazikani et al., “Standard Conformations for the Canonical Structures of Immunoglobulins,” J. Mol. Biol., 273:927-948 (1997); Abhinandan et al., “Analysis and Improvements to Kabat and Structurally Correct Numbering of Antibody Variable Domains,” Mol. Immunol., 45:3832-3839 (2008); Lefranc et al., “The IMGT unique numbering for immunoglobulins, T cell Receptors and Ig-like domains,” The Immunologist, 7:132-136 (1999); Lefranc et al., “IMGT unique numbering for immunoglobulin and T cell receptor variable domains and I superfamily V-like domains,” Dev. Comp. Immunol., 27:55-77 (2003); and Honegger et al., “Yet another numbering scheme for immunoglobulin variable domains: an automatic modeling and analysis tool,” J. Mol. Biol., 309:657-670 (2001)). In some embodiments the CDRs of a given heavy or light chain Ig sequence are determined according to IMGT notation.

[0042] The invention also provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317 or at least the CDRs thereof.

[0043] The invention also provides a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317. In some embodiments, the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise an immunoglobulin heavy chainLeydig 774215 11 variable region polypeptide with an amino acid sequence that is at least about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more identical to any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227- 242, 276-286, and 298-307 and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more identical to any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317.

[0044] As used herein amino acid or nucleic acid “sequence identity” can be determined by comparing a nucleic acid or amino acid sequence of interest to a reference nucleic acid or amino acid sequence. The percent identity is the number of nucleotides or amino acid residues that are the same (i.e., that are identical) as between the optimally aligned sequence of interest and the reference sequence divided by the length of the longest sequence (i.e., the length of either the sequence of interest or the reference sequence, whichever is longer). Alignment of sequences and calculation of percent identity can be performed using available software programs. Examples of such programs include CLUSTAL-W, T-Coffee, and ALIGN (for alignment of nucleic acid and amino acid sequences), BLAST programs (e.g., BLAST 2.1, BL2SEQ, BLASTp, BLASTn, and the like) and FASTA programs (e.g., FASTA3x, FASTM, and SSEARCH) (for sequence alignment and sequence similarity searches). Sequence alignment algorithms also are disclosed in, for example, Altschul et al., J. Molecular Biol., 215(3):403-410 (1990); Beigert et al., Proc. Natl. Acad. Sci. USA, 106(10):3770-3775 (2009); Durbin et al., eds., “Biological Sequence Analysis: Probalistic Models of Proteins and Nucleic Acids,” Cambridge University Press, Cambridge, UK (2009); Soding, Bioinformatics, 21(7):951-960 (2005); Altschul et al., Nucleic Acids Res., 25(17):3389-3402 (1997); and Gusfield, “Algorithms on Strings, Trees and Sequences,” Cambridge University Press, Cambridge UK (1997)). Percent (%) identity of sequences can be also calculated, for example, as 100 x [(identical positions) / min(TGA, TGB)], where TGAand TGB are the sum of the number of residues and internal gap positions in peptide sequences A and B in the alignment that minimizes TGA and TGB. See, e.g., Russell et al., J. Mol Biol., 244:332-350 (1994).

[0045] As mentioned above, the binding agent can comprise an Ig heavy and / or light chain variable region with at least about 90% identity (e.g., at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% identity) to a specific heavy or lightLeydig 774215 12 chain variable region sequence provided herein. Similarly, the CDRs of the Ig heavy and / or light chain variable region can have at least about 90% identity (e.g., at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% identity) to a specific CDR sequence provided herein. Thus, the Ig heavy and light chain variable region or CDR sequence can comprise at least one (e.g., 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, 8 or more, 9 or more, or 10 or more, etc., as applicable based on the length of the sequence) amino acid modification (e.g., substitution, addition, or deletion) as compared to the specific sequences provided herein, provided the binding agent maintains the ability to specifically bind the aggregated form of amyloid-beta (Aβ) peptide, optionally wherein the binding agent maintains the affinity of a binding agent with the specified sequences and / or competes with a binding agent having the specified sequences for binding to the aggregated form of amyloid-beta (Aβ) peptide.

[0046] The amino acids of the sequences provided can be substituted with any other amino acid. Amino acids include naturally-occurring α amino acids and their stereoisomers, as well as non-naturally occurring amino acids and their stereoisomers. “Stereoisomers” of a given amino acid refer to isomers having the same molecular formula and intramolecular bonds but different three-dimensional arrangements of bonds and atoms (e.g., an L-amino acid and the corresponding D-amino acid). The amino acids can be glycosylated (e.g., N- linked glycans, O-linked glycans, phosphoglycans, C-linked glycans, or glypiation) or deglycosylated.

[0047] Naturally-occurring amino acids are those encoded by the genetic code, as well as those amino acids that are later modified, e.g., hydroxyproline, γ-carboxyglutamate, and O-phosphoserine. Naturally-occurring α-amino acids include, without limitation, alanine (Ala), cysteine (Cys), aspartic acid (Asp), glutamic acid (Glu), phenylalanine (Phe), glycine (Gly), histidine (His), isoleucine (Ile), arginine (Arg), lysine (Lys), leucine (Leu), methionine (Met), asparagine (Asn), proline (Pro), glutamine (Gln), serine (Ser), threonine (Thr), valine (Val), tryptophan (Trp), tyrosine (Tyr), and combinations thereof. Stereoisomers of naturally- occurring α-amino acids include, without limitation, D-alanine (D-Ala), D-cysteine (D-Cys), D aspartic acid (D-Asp), D-glutamic acid (D-Glu), D-phenylalanine (D-Phe), D-histidine (D His), D-isoleucine (D-Ile), D-arginine (D-Arg), D-lysine (D-Lys), D-leucine (D-Leu), D methionine (D-Met), D-asparagine (D-Asn), D-proline (D-Pro), D-glutamine (D-Gln), DLeydig 774215 13 serine (D-Ser), D-threonine (D-Thr), D-valine (D-Val), D-tryptophan (D-Trp), D-tyrosine (D Tyr), and combinations thereof.

[0048] Non-naturally occurring amino acids include, without limitation, amino acid analogs, amino acid mimetics, synthetic amino acids, N-substituted glycines, and N-methyl amino acids in either the L- or D-configuration that function in a manner similar to the naturally-occurring amino acids. For example, “amino acid analogs” can be unnatural amino acids that have the same basic chemical structure as naturally-occurring amino acids (i.e., a carbon that is bonded to a hydrogen, a carboxyl group, an amino group) but have modified side-chain groups or modified peptide backbones, e.g., homoserine, norleucine, methionine sulfoxide, and methionine methyl sulfonium. “Amino acid mimetics” refer to chemical compounds that have a structure that is different from the general chemical structure of an amino acid, but that function in a manner similar to a naturally-occurring amino acid.

[0049] Amino acids may be referred to herein by either the commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission.

[0050] The amino acid substitution can be conservative, semi-conservative, or non- conservative with respect to the basic properties of the original amino acid residue. A “conservative” substitution refers to the replacement of one amino acid by another amino acid with a common property. A functional way to define common properties between individual amino acids is to analyze the normalized frequencies of amino acid changes between corresponding proteins of homologous organisms (Schulz and Schirmer, Principles of Protein Structure, Springer-Verlag, New York (1979)). According to such analyses, groups of amino acids may be defined where amino acids within a group exchange preferentially with each other, and therefore resemble each other most in their impact on the overall protein structure (Schulz and Schirmer, supra).

[0051] Amino acids are broadly grouped as “aromatic” or “aliphatic.” An aromatic amino acid includes an aromatic ring. Examples of “aromatic” amino acids include histidine (H or His), phenylalanine (F or Phe), tyrosine (Y or Tyr), and tryptophan (W or Trp). Non-aromatic amino acids are broadly grouped as “aliphatic.” Examples of “aliphatic” amino acids include glycine (G or Gly), alanine (A or Ala), valine (V or Val), leucine (L or Leu), isoleucine (I or Ile), methionine (M or Met), serine (S or Ser), threonine (T or Thr), cysteine (C or Cys), proline (P or Pro), glutamic acid (E or Glu), aspartic acid (D or Asp), asparagine (N or Asn), glutamine (Q or Gln), lysine (K or Lys), and arginine (R or Arg).Leydig 774215 14

[0052] Aliphatic amino acids may be sub-divided into four sub-groups. The “large aliphatic non-polar sub-group” consists of valine, leucine, and isoleucine. The “aliphatic slightly-polar sub-group” consists of methionine, serine, threonine, and cysteine. The “aliphatic polar / charged sub-group” consists of glutamic acid, aspartic acid, asparagine, glutamine, lysine, and arginine. The “small-residue sub-group” consists of glycine and alanine. The group of charged / polar amino acids may be sub-divided into three sub-groups: the “positively-charged sub-group” consisting of lysine and arginine, the “negatively-charged sub-group” consisting of glutamic acid and aspartic acid, and the “polar sub-group” consisting of asparagine and glutamine.

[0053] Aromatic amino acids may be sub-divided into two sub-groups: the “nitrogen ring sub-group” consisting of histidine and tryptophan and the “phenyl sub-group” consisting of phenylalanine and tyrosine.

[0054] Examples of conservative amino acid substitutions include substitutions of amino acids within the sub-groups described above, for example, lysine for arginine and vice versa such that a positive charge may be maintained, glutamic acid for aspartic acid and vice versa such that a negative charge may be maintained, serine for threonine such that a free -OH can be maintained, and glutamine for asparagine such that a free -NH2 can be maintained.

[0055] “Semi-conservative mutations” include amino acid substitutions of amino acids within the same groups listed above, but not within the same sub-group. For example, the substitution of aspartic acid for asparagine, or asparagine for lysine, involves amino acids within the same group, but different sub-groups. “Non-conservative mutations” involve amino acid substitutions between different groups, for example, lysine for tryptophan, or phenylalanine for serine, etc.

[0056] In addition, one or more amino acids can be inserted into the aforementioned immunoglobulin heavy or light chain variable region polypeptides. Any number of any suitable amino acids can be inserted into the amino acid sequence of the immunoglobulin heavy or light chain variable region polypeptide. In this respect, at least one amino acid (e.g., 2 or more, 5 or more, or 10 or more amino acids), but not more than 20 amino acids (e.g., 18 or less, 15 or less, or 12 or less amino acids), can be inserted into the amino acid sequence of the immunoglobulin heavy or light chain variable region polypeptide. Preferably, 1-10 amino acids (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acids) are inserted into the amino acid sequence of the immunoglobulin heavy or light chain variable region polypeptide. In this respect, the amino acid(s) can be inserted into any one of the aforementionedLeydig 774215 15 immunoglobulin heavy or light chain variable region polypeptides in any suitable location. In some embodiments, the amino acid(s) are inserted into a CDR (e.g., CDR1, CDR2, or CDR3) of the immunoglobulin heavy or light chain variable region polypeptide; in other embodiments, the amino acids are inserted into a framework region.

[0057] In embodiments, the binding agent targeted to the aggregated form of amyloid- beta (Aβ) peptide disclosed herein comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of SEQ ID NO: 83, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of SEQ ID NO: 84, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of SEQ ID NO: 85, and the LCDR3 of SEQ ID NO: 105; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of SEQ ID NO: 87, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 108; the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of SEQ ID NO: 89, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO: 110; the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of SEQ ID NO: 91, and the LCDR3 of SEQ ID NO: 111; the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of SEQ ID NO: 92, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of SEQ ID NO: 93, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of SEQ ID NO: 94, and the LCDR3 of SEQ ID NO: 114; the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of SEQLeydig 774215 16 ID NO: 95, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of SEQ ID NO: 96, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO: 117; the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of SEQ ID NO: 98, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of SEQ ID NO: 99, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of SEQ ID NO: 100, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of SEQ ID NO: 101, and the LCDR3 of SEQ ID NO: 121; or the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of SEQ ID NO: 102, and the LCDR3 of SEQ ID NO: 122. In embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of the amino acid sequence of WAS, and the LCDR3 of SEQ ID NO: 105; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 108; the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of the amino acid sequence ofLeydig 774215 17 KVS, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of the amino acid sequence of KVF, and the LCDR3 of SEQ ID NO: 110; the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 111; the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 114; the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 117; the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 121; or the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 122. In embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, theLeydig 774215 18 HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 273, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 274, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266,Leydig 774215 19 the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 275. In embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVF, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQLeydig 774215 20 ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence of KVS, and the LCDR3 of SEQ ID NO: 275.

[0058] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein is an antibody or an antigen-binding fragment thereof.Leydig 774215 21

[0059] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide provide herein is an antibody. In some embodiments, the binding agent is a whole (or complete) antibody, which comprises an antigen binding domain comprising the Ig heavy and light variable domains as well as a fragment crystallizable (Fc) domain. An exemplary antibody structure is a tetramer composed of two pairs of polypeptide chains, each pair having one “light” (a smaller chain, such as about 25 kDa) and one “heavy” chain (a larger chain, such as about 50-70 kDa), typically connected by disulfide bonds. Each chain is composed of structural domains, which are referred to as immunoglobulin domains. These domains are classified into different categories by size and function, e.g., variable domains or regions on the light and heavy chains (VL and VH, respectively) and constant domains or regions on the light and heavy chains (CL and CH, respectively). The N terminus of each chain defines a variable region, typically about 100 to 110 or more amino acids (but not limited thereto), referred to as the paratope, primarily responsible for antigen recognition, i.e., the antigen binding domain. Light chains are classified as either kappa or lambda. Heavy chains are classified as gamma, mu, alpha, delta, or epsilon, which in turn define the immunoglobulin classes, IgG, IgM, IgA, IgD and IgE, respectively. The classes can be further divided into subclasses. For instance, there are four IgG subclasses (IgG1, IgG2, IgG3, and IgG4) in humans, named in order of their abundance in serum (i.e., IgG1 is the most abundant). In some embodiments, the antibody is an IgG, IgM, IgA, IgD or IgE antibody. In some embodiments, the antibody is an IgG antibody.

[0060] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide provided herein is an antibody fragment selected from F(ab’)2, Fab’, Fab, Fv, scFv, dsFv, dAb, and a single chain binding polypeptide. As used herein, the term “antibody fragment” refers to an antigen binding construct that comprises at least an antigen-binding region of an antibody, alone or with other components that together constitute the antigen-binding construct. Many different types of antibody “fragments” are known in the art, including, for instance, (i) a Fab fragment, which is a monovalent fragment consisting of the VL, VH, CL, and CH1 domains, (ii) a F(ab’)2 fragment, which is a bivalent fragment comprising two Fab fragments linked by a disulfide bridge at the hinge region, (iii) a Fv fragment consisting of the VL and VH domains of a single arm of an antibody, (iv) a Fab’ fragment, which results from breaking the disulfide bridge of an F(ab’)2fragment using mild reducing conditions, (v) a disulfide-stabilized Fv fragment (dsFv), and (vi) a single chain Fv (scFv), which is a monovalent molecule consisting of the two domains of the Fv fragmentLeydig 774215 22 (i.e., VLand VH) joined by a synthetic linker which enables the two domains to be synthesized as a single polypeptide chain.

[0061] In some embodiments, the antibody is humanized. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide can be, or can be obtained from, a human antibody, a non-human antibody, a humanized antibody, or a chimeric antibody, or corresponding antibody fragments. As used herein the term “chimeric” refers to an antibody or fragment thereof typically comprising human constant regions and non-human variable regions. As used herein the term “humanized” refers to a monoclonal antibody typically comprising a human antibody scaffold but with non-human origin amino acids or sequences in at least one CDR (e.g., 1, 2, 3, 4, 5, or all six CDRs).

[0062] Methods for generating such antibodies are known in the art and are described in, for example, Köhler and Milstein, Eur. J. Immunol., 5:511-519 (1976); Harlow and Lane (eds.), “Antibodies: A Laboratory Manual,” CSH Press (1988); and Janeway et al. (eds.), “Immunobiology,” 9th Ed., Garland Publishing, New York, NY (2017). In certain embodiments, a human or chimeric antibody or antibody fragment can be generated using a transgenic animal (e.g., a mouse) wherein one or more endogenous immunoglobulin genes are replaced with one or more human immunoglobulin genes. Examples of transgenic mice wherein endogenous antibody genes are effectively replaced with human antibody genes include, but are not limited to, the Medarex HUMAB-MOUSE™, the Kirin TC MOUSE™, and the Kyowa Kirin KM-MOUSE™ (see, e.g., Lonberg, Nat. Biotechnol., 23(9):1117-25 (2005), and Lonberg, Handb. Exp. Pharmacol., 181:69-97 (2008)). A humanized antibody can be generated using any suitable method known in the art (see, e.g., An, Z. (ed.), Therapeutic Monoclonal Antibodies: From Bench to Clinic, John Wiley & Sons, Inc., Hoboken, New Jersey (2009)), including, e.g., grafting of non-human CDRs onto a human antibody scaffold (see, e.g., Kashmiri et al., Methods, 36(1):25-34 (2005) and Hou et al., J. Biochem., 144(1):115-120 (2008)) and use of phage display (see, e.g., Fellouse, et al., Journal of Molecular Biology, 373(4):924-940 (2007) and Glanville, et al., Proc. Natl. Acad. Sci. USA, 106(48):20216-20221 (2009)).

[0063] In some embodiments, the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106. In some embodiments, the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide describedLeydig 774215 23 herein comprise the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 163 and 179, SEQ ID NOs: 164 and 180, SEQ ID NOs: 165 and 181, SEQ ID NOs: 166 and 182, SEQ ID NOs: 167 and 183, SEQ ID NOs: 168 and 184, SEQ ID NOs: 169 and 185, SEQ ID NOs: 170 and 186, SEQ ID NOs: 171 and 187, SEQ ID NOs: 172 and 188, SEQ ID NOs: 173 and 189, SEQ ID NOs: 174 and 190, SEQ ID NOs: 175 and 191, SEQ ID NOs: 176 and 192, SEQ ID NOs: 177 and 193, or SEQ ID NOs: 178 and 194.

[0064] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO: 110. In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 195 and 211, SEQ ID NOs: 196 and 212, SEQ ID NOs: 197 and 213, SEQ ID NOs: 198 and 214, SEQ ID NOs: 199 and 215, SEQ ID NOs: 200 and 216, SEQ ID NOs: 201 and 217, SEQ ID NOs: 202 and 218, SEQ ID NOs: 203 and 219, SEQ ID NOs: 204 and 220, SEQ ID NOs: 205 and 221, SEQ ID NOs: 206 and 222, SEQ ID NOs: 207 and 223, SEQ ID NOs: 208 and 224, SEQ ID NOs: 209 and 225, or SEQ ID NOs: 210 and 226.

[0065] In some embodiments, the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO: 117. In some embodiments the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein comprise the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 227 and 243, SEQ ID NOs: 228 and 244, SEQ ID NOs: 229 and 245, SEQ ID NOs: 230 and 246, SEQ ID NOs: 231 and 247, SEQ ID NOs: 232 and 248, SEQ ID NOs: 233 and 249, SEQ ID NOs: 234 and 250, SEQ ID NOs: 235 and 251, SEQ ID NOs: 236 and 252, SEQ ID NOs: 237 and 253, SEQ ID NOs: 238 and 254, SEQ ID NOs: 239 and 255, SEQ ID NOs: 240 and 256, SEQ ID NOs: 241 and 257, or SEQ ID NOs: 242 and 258.

[0066] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein is, or is part of, a multispecific or bispecific antibody, chimeric antigen receptor, chimeric T cell receptor, bispecific T-cell engager, multivalent antibody, diabody, triabody, tetrabody, hexabody, bis-scFv fragment, Fab dimer, or Fab trimer. In some embodiments the binding agent can be monospecific for theLeydig 774215 24 aggregated form of amyloid-beta (Aβ) peptide, or can be bispecific or multi-specific. For instance, in bivalent or multivalent antibodies or antibody fragments, the binding domains can be different, and each binding domain can target different epitopes of the same antigen or target different antigens.

[0067] Methods of constructing multivalent binding constructs are known in the art. Bispecific and multispecific antibodies are known in the art. Furthermore, a diabody, triabody, tetrabody, or hexabody can be provided, which is a dimer, trimer, tetramer, or hexamer of polypeptide chains each comprising a VH connected to a VL by a peptide linker that is too short to allow pairing between the VH and VL on the same polypeptide chain, thereby driving the pairing between the complementary domains on different VH -VL polypeptide chains to generate a multimeric molecule having two, three, four, or six functional antigen binding sites. Also, bis-scFv fragments, which are small scFv fragments with two different variable domains can be generated to produce bispecific bis-scFv fragments capable of binding two different epitopes. Fab dimers (Fab2) and Fab trimers (Fab3) can be produced using genetic engineering methods to create multispecific constructs based on Fab fragments.

[0068] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein has more than two binding domains per molecule, e.g., three binding domains per molecule, four binding domains per molecule, five binding domains per molecule, or six binding domains per molecule. In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein having more than two binding domains per molecule has a higher avidity of binding to sAβ aggregates as compared to the avidity of binding to sAβ aggregates of a binding agent having two or less binding domains per molecule, e.g., having two binding domains per molecule, or having one binding domain per molecule.

[0069] The blood-brain barrier (BBB) is known to prevent penetration of large molecules, such as an antibody, from the blood into the central nervous system (CNS). To facilitate transfer of large molecules across the BBB, a BBB shuttle can be used according to the invention. A BBB shuttle is any moiety that, when conjugated with a binding agent, increases the exposure of the binding agent within the CNS after systemic administration. Such a shuttle can be used to facilitate the transfer across the BBB of the binding agents disclosed herein. Any BBB shuttle increasing CNS exposure can be used with the binding agents of the invention. Desirably, the BBB shuttle increases the exposure of the binding agent within theLeydig 774215 25 CNS after systemic administration as compared to exposure of the binding agent, without the BBB shuttle, within the CNS after systemic administration under the same conditions.

[0070] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein is conjugated to a BBB shuttle moiety. In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide disclosed herein is connected to a BBB shuttle protein to improve the engagement with amyloid plaque. The resultant protein can be used as a therapeutic agent. In some embodiments, the BBB shuttle moiety is a binding agent which targets a molecule present on cell types relevant to the BBB which are exposed to blood and / or brain fluids such as CSF; binding to this molecule results in increased CNS delivery of shuttle and cargo relative to cargo alone, with the cargo molecule being the binding agent to the aggregated form of Aβ. In some embodiments, the BBB shuttle moiety is a binding agent targeted to a transferrin receptor (TfR). In some embodiments, the BBB shuttle moiety is a binding agent targeted to CD98 heavy chain. In some embodiments, the BBB shuttle moiety is a binding agent targeted to IGF-1 receptor. In some embodiments, the BBB shuttle moiety is a binding agent targeted to insulin receptor. In some embodiments, the BBB shuttle moiety is a binding agent targeted to an LDLR family protein. In some embodiments, the BBB shuttle moiety is a binding agent targeted to GLUT1. In some embodiments, the BBB shuttle moiety is a binding agent targeted to leptin receptor. In some embodiments, the BBB shuttle moiety is a binding agent targeted to TMEM30A. In some embodiments, the BBB shuttle moiety is an antibody or an antigen-binding fragment thereof. In some embodiments, the BBB shuttle moiety is a single chain variable fragment (scFv). In some embodiments, the BBB shuttle moiety is a heavy chain only variable domain (VHH). In some embodiments, the BBB shuttle is a peptide. In some embodiments, the BBB shuttle is a non-polypeptide, including but not limited to, small synthetic molecules, peptides made of non-natural amino acids, viruses, and particles derived from viruses. The complexing of a cargo and a shuttle may be achieved by covalent or non- covalent bonds.

[0071] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein is an antibody conjugate. In this respect, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide can be a conjugate of (1) an antibody, an alternative scaffold, or fragments thereof, and (2) a protein or non-protein moiety. For example, the binding agent targeted to the aggregated form ofLeydig 774215 26 amyloid-beta (Aβ) peptide can be conjugated to a peptide, a fluorescent molecule, or an immune-activating or immune-suppressive agent.

[0072] In some embodiments, the BBB shuttle is a non-polypeptide, including but not limited to, small synthetic molecules, peptides made of non-natural amino acids, viruses, and particles derived from viruses. The complexing of a cargo and a shuttle may be achieved by covalent or non-covalent bonds.

[0073] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein can have any suitable affinity to the aggregated form of amyloid-beta (Aβ) peptide or an epitope thereof. As used herein, the term “affinity” refers to the equilibrium constant for the reversible binding of two agents and is expressed as the dissociation constant (KD). Affinity of a binding agent to a ligand, such as affinity of an antibody for an epitope, can be, for example, from about 1 picomolar (pM) to about 1 micromolar (μM) (e.g., from about 1 picomolar (pM) to about 1 nanomolar (nM), or from about 1 nM to about 1 micromolar (μM)). In some embodiments the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein can bind to a human aggregated form of amyloid-beta (Aβ) peptide with a KD less than or equal to 1 micromolar (e.g., 0.9 μM, 0.8 μM, 0.7 μM, 0.6 μM, 0.5 μM, 0.4 μM, 0.3 μM, 0.2 μM, 0.1 μM, 0.05 μM, 0.025 μM, 0.01 μM, 0.001 μM, or a range defined by any two of the foregoing values). In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein can bind to a human aggregated form of amyloid-beta (Aβ) peptide with a KD less than or equal to 200 nanomolar (e.g., 190 nM, 175 nM, 150 nM, 125 nM, 110 nM, 100 nM, 90 nM, 80 nM, 75 nM, 60 nM, 50 nM, 40 nM, 30 nM, 25 nM, 20 nM, 15 nM, 10 nM, 5 nM, 1 nM, or a range defined by any two of the foregoing values). In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein can bind to a human aggregated form of amyloid-beta (Aβ) peptide with a KD less than or equal to 1 nanomolar (e.g., 0.9 nM, 0.8 nM, 0.7 nM, 0.6 nM, 0.5 nM, 0.4 nM, 0.3 nM, 0.2 nM, 0.1 nM, 0.05 nM, 0.025 nM, 0.01 nM, 0.001 nM, or a range defined by any two of the foregoing values). In another embodiment, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein can bind to human the aggregated form of amyloid-beta (Aβ) peptide with a KD less than or equal to 200 pM (e.g., 190 pM, 175 pM, 150 pM, 125 pM, 110 pM, 100 pM, 90 pM, 80 pM, 75 pM, 60 pM, 50 pM, 40 pM, 30 pM, 25 pM, 20 pM, 15 pM, 10 pM, 5 pM, 1 pM, or a range defined by any two of the foregoing values).Leydig 774215 27

[0074] In some embodiments, the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein also binds to a non-human species of the aggregated form of amyloid-beta (Aβ) peptide that is useful for development in animal models (e.g., toxicity screens and the like).

[0075] Immunoglobulin affinity for an antigen or epitope of interest can be measured using any art-recognized assay. Such methods include, for example, fluorescence activated cell sorting (FACS), separable beads (e.g., magnetic beads), surface plasmon resonance (SPR), solution phase competition (KINEXA™), antigen panning, and / or ELISA (see, Janeway et al. (eds.), Immunobiology, 9th Ed., Garland Publishing, New York, NY (2017)). In some embodiments, the binding agent (e.g., an antibody or antigen-binding antibody fragment) has an affinity to the human aggregated form of amyloid-beta (Aβ) peptide as described above as determined by SPR or as determined by solution-phase competition assay. In some embodiments, the binding agent (e.g., an antibody or antigen-binding antibody fragment) has an affinity to human the aggregated form of amyloid-beta (Aβ) peptide as described above as determined by ELISA or as determined by FACS.

[0076] The invention also provides a nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of any one of the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein.

[0077] The term “nucleic acid sequence” is intended to encompass a polymer of DNA or RNA, i.e., a polynucleotide, which can be single-stranded or double-stranded and which can contain non-natural or altered nucleotides. The terms “nucleic acid” and “polynucleotide” as used herein refer to a polymeric form of nucleotides of any length, either ribonucleotides (RNA) or deoxyribonucleotides (DNA). These terms refer to the primary structure of the molecule, and thus include double- and single-stranded DNA, and double- and single- stranded RNA. The terms include, as equivalents, analogs of either RNA or DNA made from nucleotide analogs and modified polynucleotides such as, though not limited to, methylated and / or capped polynucleotides. Nucleic acids are typically linked via phosphate bonds to form nucleic acid sequences or polynucleotides, though many other linkages are known in the art (e.g., phosphorothioates, boranophosphates, and the like). The nucleic acid can be part of a vector.

[0078] The invention also provides a vector comprising a nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of anyLeydig 774215 28 one of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein. Any type of vector can be used, particularly an expression vector useful for expressing the polypeptides in a cell. The vector can be, for example, a plasmid, episome, cosmid, viral vector (e.g., retroviral or adenoviral), or phage. Suitable vectors and methods of vector preparation are well known in the art (see, e.g., Sambrook et al., “Molecular Cloning, a Laboratory Manual,” 3rd edition, Cold Spring Harbor Press, Cold Spring Harbor, N.Y. (2001); and Ausubel et al., “Current Protocols in Molecular Biology,” Greene Publishing Associates and John Wiley & Sons, New York, N.Y. (1994)).

[0079] The vector preferably comprises expression control sequences, such as promoters, enhancers, polyadenylation signals, transcription terminators, internal ribosome entry sites (IRES), and the like, that provide for the expression of the coding sequence in a host cell. Exemplary expression control sequences are known in the art and described in, for example, Goeddel, Gene Expression Technology: Methods in Enzymology, Vol.185, Academic Press, San Diego, Calif. (1990).

[0080] A large number of promoters, including constitutive, inducible, and repressible promoters, from a variety of different sources are well known in the art. Representative sources of promoters include for example, virus, mammal, insect, plant, yeast, and bacteria, and suitable promoters from these sources are readily available, or can be made synthetically, based on sequences publicly available, for example, from depositories such as the American Type Culture Collection (ATCC) as well as other commercial or individual sources. Promoters can be unidirectional (i.e., initiate transcription in one direction) or bi-directional (i.e., initiate transcription in either a 3’ or 5’ direction). Non-limiting examples of promoters include, for example, the T7 bacterial expression system, pBAD (araA) bacterial expression system, the cytomegalovirus (CMV) promoter, the SV40 promoter, the RSV promoter. Inducible promoters include, for example, the Tet system (U.S. Patents 5,464,758 and 5,814,618), the Ecdysone inducible system (No et al., Proc. Natl. Acad. Sci. USA, 93:3346- 3351 (1996)), the T-REX™ system (Invitrogen, Carlsbad, CA), LACSWITCH™ system (Stratagene, San Diego, CA), and the Cre-ERT tamoxifen inducible recombinase system (Indra et al., Nuc. Acid. Res., 27:4324-4327 (1999); Nuc. Acid. Res., 28:e99 (2000); U.S. Patent 7,112,715; and Kramer & Fussenegger, Methods Mol. Biol., 308:123-144 (2005)).

[0081] The term “enhancer” as used herein, refers to a DNA sequence that increases transcription of, for example, a nucleic acid sequence to which it is operably linked. Enhancers can be located many kilobases away from the coding region of the nucleic acidLeydig 774215 29 sequence and can mediate the binding of regulatory factors, patterns of DNA methylation, or changes in DNA structure. A large number of enhancers from a variety of different sources are well known in the art and are available as or within cloned polynucleotides (from, e.g., depositories such as the ATCC as well as other commercial or individual sources). A number of polynucleotides comprising promoters (such as the commonly-used CMV promoter) also comprise enhancer sequences. Enhancers can be located upstream, within, or downstream of coding sequences.

[0082] The vector also can comprise a “selectable marker gene.” The term “selectable marker gene,” as used herein, refers to a nucleic acid sequence that allow cells expressing the nucleic acid sequence to be specifically selected for or against, in the presence of a corresponding selective agent. Suitable selectable marker genes are known in the art and described in, e.g., International Patent Application Publications WO 1992 / 008796 and WO 1994 / 028143; Wigler et al., Proc. Natl. Acad. Sci. USA, 77:3567-3570 (1980); O’Hare et al., Proc. Natl. Acad. Sci. USA, 78:1527-1531 (1981); Mulligan & Berg, Proc. Natl. Acad. Sci. USA, 78:2072-2076 (1981); Colberre-Garapin et al., J. Mol. Biol., 150:1-14 (1981); Santerre et al., Gene, 30:147-156 (1984); Kent et al., Science, 237:901-903 (1987); Wigler et al., Cell, 11:223-232 (1977); Szybalska & Szybalski, Proc. Natl. Acad. Sci. USA, 48:2026-2034 (1962); Lowy et al., Cell, 22:817-823 (1980); and U.S. Patents 5,122,464 and 5,770,359.

[0083] In some embodiments, the vector is an “episomal expression vector” or “episome,” which is able to replicate in a host cell, and persists as an extrachromosomal segment of DNA within the host cell in the presence of appropriate selective pressure (see, e.g., Conese et al., Gene Therapy, 11:1735-1742 (2004)). Representative commercially available episomal expression vectors include, but are not limited to, episomal plasmids that utilize Epstein Barr Nuclear Antigen 1 (EBNA1) and the Epstein Barr Virus (EBV) origin of replication (oriP). The vectors pREP4, pCEP4, pREP7, and pcDNA3.1 from Invitrogen (Carlsbad, CA) and pBK-CMV from Stratagene (La Jolla, CA) represent non-limiting examples of an episomal vector that uses T-antigen and the SV40 origin of replication in lieu of EBNA1 and oriP.

[0084] Other suitable vectors include integrating expression vectors, which may randomly integrate into the host cell’s DNA, or may include a recombination site to enable the specific recombination between the expression vector and the host cell’s chromosome. Such integrating expression vectors may utilize the endogenous expression control sequences of the host cell’s chromosomes to effect expression of the desired protein. Examples ofLeydig 774215 30 vectors that integrate in a site specific manner include, for example, components of the flp-in system from Invitrogen (Carlsbad, CA) (e.g., pcDNA™5 / FRT), or the cre-lox system, such as can be found in the pExchange-6 Core Vectors from Stratagene (La Jolla, CA). Examples of vectors that randomly integrate into host cell chromosomes include, for example, pcDNA3.1 (when introduced in the absence of T-antigen) from Invitrogen (Carlsbad, CA), UCOE from Millipore (Billerica, MA), and pCI or pFN10A (ACT) FLEXI™ from Promega (Madison, WI).

[0085] Viral vectors also can be used. Representative commercially available viral expression vectors include, but are not limited to, the adenovirus-based Per.C6 system available from Crucell, Inc. (Leiden, The Netherlands), the lentiviral-based pLP1 from Invitrogen (Carlsbad, CA), and the retroviral vectors pFB-ERV plus pCFB-EGSH from Stratagene (La Jolla, CA).

[0086] The invention also provides an isolated cell comprising any one of the described nucleic acids or the described vectors.

[0087] Nucleic acid sequences encoding the heavy and light chain immunoglobulin sequences can be provided to a cell on the same vector (i.e., in cis). A unidirectional promoter can be used to control expression of each nucleic acid sequence. In another embodiment, a combination of bidirectional and unidirectional promoters can be used to control expression of multiple nucleic acid sequences. Nucleic acid sequences encoding the inventive amino acid sequences alternatively can be provided to the population of cells on separate vectors (i.e., in trans). Each of the nucleic acid sequences in each of the separate vectors can comprise the same or different expression control sequences. The separate vectors can be provided to cells simultaneously or sequentially.

[0088] The vector(s) comprising the nucleic acid(s) encoding the inventive amino acid sequences can be introduced into a host cell that is capable of expressing the polypeptides encoded thereby, including any suitable prokaryotic or eukaryotic cell. As such, the invention provides an in vitro (isolated) cell or cell line comprising the inventive vector, which expresses the immunoglobulin heavy and light chain polypeptides. Preferred host cells are those that can be easily and reliably grown, have reasonably fast growth rates, have well characterized expression systems, and can be transformed or transfected easily and efficiently.

[0089] Examples of suitable prokaryotic cells include, but are not limited to, cells from the genera Bacillus (such as Bacillus subtilis and Bacillus brevis), Escherichia (such as E.Leydig 774215 31 coli), Pseudomonas, Streptomyces, Salmonella, and Erwinia. Particularly useful prokaryotic cells include the various strains of Escherichia coli (e.g., K12, HB101 (ATCC No.33694), DH5α, DH10, MC1061 (ATCC No.53338), and CC102).

[0090] Preferably, the vector is introduced into a eukaryotic cell. Suitable eukaryotic cells are known in the art and include, for example, yeast cells, insect cells, and mammalian cells. Examples of suitable yeast cells include those from the genera Kluyveromyces, Pichia, Rhino-sporidium, Saccharomyces, and Schizosaccharomyces. Preferred yeast cells include, for example, Saccharomyces cerivisae and Pichia pastoris.

[0091] Suitable insect cells are described in, for example, Kitts et al., Biotechniques, 14:810-817 (1993); Lucklow, Curr. Opin. Biotechnol., 4:564-572 (1993); and Lucklow et al., J. Virol., 67:4566-4579 (1993). Preferred insect cells include Sf-9 and HI5 (Invitrogen, Carlsbad, CA).

[0092] Preferably, mammalian cells are utilized in the invention. A number of suitable mammalian host cells are known in the art, and many are available from ATCC. Examples of suitable mammalian cells include, but are not limited to, Chinese hamster ovary cells (CHO) cells, such as CHO-K1 cells (ATCC No. CCL61), CHO DHFR-cells (Urlaub et al., Proc. Natl. Acad. Sci. USA, 97:4216-4220 (1980)), human embryonic kidney (HEK) 293 or 293T cells (ATCC No. CRL1573), and 3T3 cells (ATCC No. CCL92). Other suitable mammalian cell lines are the monkey COS-1 (ATCC No. CRL1650) and COS-7 cell lines (ATCC No. CRL1651), as well as the CV-1 cell line (ATCC No. CCL70). Further exemplary mammalian host cells include primate cell lines and rodent cell lines, including transformed cell lines. Normal diploid cells, cell strains derived from in vitro culture of primary tissue, as well as primary explants, are also suitable. Other suitable mammalian cell lines include, but are not limited to, mouse neuroblastoma N2A cells, HeLa, mouse L-929 cells, and BHK or HaK hamster cell lines, all of which are available from the ATCC. Suitable cell lines also include hybridomas. Methods for selecting suitable mammalian host cells and methods for transformation, culture, amplification, screening, and purification of cells are known in the art.

[0093] The mammalian cell can be a human cell. For example, the mammalian cell can be a human lymphoid or lymphoid derived cell line, such as a cell line of pre-B lymphocyte origin. Examples of human lymphoid cells lines include, without limitation, RAMOS (CRL- 1596), Daudi (CCL-213), EB-3 (CCL-85), DT40 (CRL-2111), 18-81 (Jack et al., Proc. Natl. Acad. Sci. USA, 85:1581-1585 (1988)), Raji cells (CCL-86), and derivatives thereof.Leydig 774215 32

[0094] A nucleic acid sequence encoding the inventive amino acid sequence may be introduced into a cell by “transfection,” “transformation,” or “transduction.” “Transfection,” “transformation,” or “transduction,” as used herein, refer to the introduction of one or more exogenous polynucleotides into a host cell by using physical or chemical methods. Many transfection techniques are known in the art and include, for example, calcium phosphate DNA co-precipitation (see, e.g., Murray E.J. (ed.), Methods in Molecular Biology, Vol.7, Gene Transfer and Expression Protocols, Humana Press (1991)); DEAE-dextran; electroporation; cationic liposome-mediated transfection; tungsten particle-facilitated microparticle bombardment (Johnston, Nature, 346:776-777 (1990)); and strontium phosphate DNA co-precipitation (Brash et al., Mol. Cell Biol., 7:2031-2034 (1987)). Phage or viral vectors can be introduced into host cells, after growth of infectious particles in suitable packaging cells, many of which are commercially available.

[0095] The invention also provides a method of providing a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein, the method comprising expressing in a cell in vitro one or more nucleic acids encoding the immunoglobulin heavy and light chain polypeptides thereof.

[0096] The invention also provides a composition comprising any one of the described binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, the described nucleic acids, or the described vectors, and a pharmaceutically acceptable carrier. Any suitable carrier can be used within the context of the invention, and such carriers are well known in the art. The choice of carrier will be determined, in part, by the particular site to which the composition may be administered and the particular method used to administer the composition. The composition optionally can be sterile. The composition can be frozen or lyophilized for storage and reconstituted in a suitable sterile carrier prior to use. The compositions can be generated in accordance with conventional techniques described in, e.g., Remington: The Science and Practice of Pharmacy, 21st Edition, Lippincott Williams & Wilkins, Philadelphia, PA (2001).

[0097] In some embodiments, the composition is formulated for nasal administration, intravenous injection, subcutaneous injection, or intraperitoneal injection. In some embodiments, the composition is formulated for intravenous injection. In some embodiments, the composition is formulated for subcutaneous injection. The composition can be formulated for parenteral administration, such as IV administration or administration into a body cavity or lumen of an organ. Compositions for injection will commonly comprise the activeLeydig 774215 33 ingredient dissolved or suspended in a pharmaceutically acceptable carrier. Among the acceptable vehicles and solvents that can be employed are water and an isotonic solution of one or more salts such as sodium chloride, e.g., Ringer’s solution. In addition, sterile fixed oils can conventionally be employed as a solvent or suspending medium. For this purpose, any bland fixed oil can be employed, including synthetic monoglycerides or diglycerides. In addition, fatty acids such as oleic acid can likewise be used in the preparation of injectables. These compositions desirably are sterile and generally free of undesirable matter. These compositions can be sterilized by conventional, well known sterilization techniques. The compositions can contain pharmaceutically acceptable auxiliary substances as required to approximate physiological conditions such as pH adjusting and buffering agents, toxicity adjusting agents, e.g., sodium acetate, sodium chloride, potassium chloride, calcium chloride, sodium lactate and the like.

[0098] The composition can contain any suitable concentration of the described binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide, described nucleic acids encoding same, or described vectors effective to elicit a therapeutic response. The concentration can vary widely, and will be selected primarily based on fluid volumes, viscosities, body weight, and the like, in accordance with the particular mode of administration selected and the patient's needs. In certain embodiments, the concentration of the described immunoglobulin heavy chain polypeptide, the described immunoglobulin light chain polypeptide, the described binding agent targeted to the aggregated form of amyloid- beta (Aβ) peptide, the described nucleic acids encoding any of the foregoing, or the described vector comprising any one of the described nucleic acids in a solution formulation for injection will range from about 0.1% (w / w) to about 10% (w / w).

[0099] Any of the described binding agents targeted to the aggregated form of amyloid- beta (Aβ) peptide, or the described compositions, are for use as a medicament for treating a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid- beta (Aβ) peptide binding or clearance. In some embodiments of the described uses the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition, including but not limited to Alzheimer’s disease, Down’s syndrome, Parkinson’s disease and various types of dementia with or without brain pathology.

[0100] In some embodiments, any of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the compositions described herein, are for use as a medicament for treating a disease, disorder, or condition in a mammal that is responsive toLeydig 774215 34 aggregated form of amyloid-beta (Aβ) peptide binding or clearance. In some embodiments of the described uses, the disease, disorder, or condition is a disease, disorder, or condition that is clinically noted outside of the brain, e.g. Aβ-positive inclusion-body myopathy, Cerebral Amyloid Angiopathy (CAA).

[0101] As used herein, the term “neurodegenerative disease, disorder, or condition” refers to a class of neurological diseases, disorders, or conditions where the neurological disease, disorder, or condition is characterized by a gradual and progressive loss of neural tissue, and / or altered neurological function, typically reduced neurological function as a result of a gradual and progressive loss of neural tissue. This gradual loss may take place in the brain or outside of the brain where nerve cells are present. Examples of neurodegenerative diseases, disorders, and conditions include, but are not limited to acute and chronic disorders of the central nervous (CNS) and peripheral nervous system (PNS), such as Alzheimer’s disease, Down’s syndrome, Parkinson’s disease, amyotrophic lateral sclerosis (ALS), Huntington’s disease, dementia with Lewy bodies (DLB), pure autonomic failure (PAF), Bradbury- Eggleston syndrome, multiple system atrophy (MSA), Lewy body variant of Alzheimer’s disease (AD), spinal muscular atrophy (SMA), Friedreich ataxia, Hallervorden-Spatz disease, pantothenate kinase associated neurodegeneration (PKAN), and neurodegeneration with brain iron accumulation type 1 (NBIA1). In some embodiments, the neurodegenerative disease, disorder, or condition described herein includes a neurodegenerative disease, disorder, or condition where there is an increase in pathogenic aggregated forms of Aβ that are neurotoxic, disrupt synaptic function, and lead to cognitive deficits. Examples of neurodegenerative diseases where there is an increase in pathogenic aggregated forms of Aβ include, but are not limited to, Alzheimer's disease and Down’s syndrome. In some embodiments of the described uses, the neurodegenerative disease, disorder, or condition is Alzheimer’s disease. In some embodiments of the described uses the neurodegenerative disease, disorder, or condition is Down’s syndrome. In some embodiments of the described uses the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition that is characterized by ocular deposition of aggregated Aβ. In some embodiments of the described uses the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition that is characterized by deposition of aggregated Aβ outside the central nervous system.

[0102] In some embodiments, the described binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide (e.g., antibody or antibody fragment) induces clearance byLeydig 774215 35 promoting antibody dependent cell-mediated phagocytosis (ADCP). ADCP is a cellular process by which effector cells with phagocytic potential, such as microglia, monocytes, and macrophages, can internalize target cells. Once phagocytosed, the target cell resides in a phagosome, which fuses with a lysosome to begin degradation of the target cell via an oxygen-dependent or independent mechanism. This function is dependent on opsonization, or identification of the target cell with a binding agent, which then also serves as a bridge between the target cell and the phagocytic cell. Mechanistically, the binding agent binds its cognate antigen on the target cell through its antigen recognition domain, and then recruits the phagocytic cell to the target with its Fc region. Once bound to the Fc receptor of the phagocytic cell, the target cell is ingested and degraded. This process also leads to the production of soluble factors by the effector cells that help initiate and drive the immune response.

[0103] The invention also provides a method for treating or preventing a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance, the method comprising administering any one of the described binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the described compositions, to the mammal.

[0104] As used herein, the terms “treat,” “treatment,” and “treating” refer to any indicia of success in the treatment or amelioration of a condition (e.g., Alzheimer’s disease), including any objective or subjective parameter such as abatement; diminishing of symptoms or making the symptom, injury, or condition more tolerable to the patient; reduction in the rate of symptom progression; decreasing the frequency or duration of the symptom or condition; or, in some situations, preventing the onset of the symptom. The treatment or amelioration of symptoms can be based on any objective or subjective parameter, including, for example, the result of a physical examination. In this respect, the described compounds, pharmaceutical compositions, and methods can provide any amount of any level of treatment. Furthermore, the treatment provided by the disclosed method can include the treatment of one or more conditions or symptoms of the disease or condition being treated.

[0105] As used herein, the terms “mammal” refers to any subject for whom diagnosis, treatment, or therapy is desired (e.g., humans). Mammal may refer to any animal classified as a mammal, including but not limited to, humans, domestic and farm animals, and zoo, sports, or pet animals, such as dogs, horses, cats, cows, sheep, goats, pigs, camels, etc. In some embodiments the mammal is a human.Leydig 774215 36

[0106] As used herein, the term “administering” refers to parenteral, intravenous, intraperitoneal, intramuscular, intratumoral, intralesional, intranasal, or subcutaneous administration, oral administration, administration as a suppository, topical contact, intrathecal administration, or the implantation of a slow release device, e.g., a mini osmotic pump, to the subject. In some embodiments the administration is via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection. In some embodiments, the administration is via intravenous injection. In some embodiments, the administration is via subcutaneous injection.

[0107] The exact dose of the described binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the described composition will depend on the purpose of the treatment, and will be ascertainable by one skilled in the art using known techniques (see, e.g., Lieberman, Pharmaceutical Dosage Forms (vols.13, 1992); Lloyd, The Art, Science and Technology of Pharmaceutical Compounding (1999); Pickar, Dosage Calculations (1999); Goodman & Gilman’s The Pharmacological Basis of Therapeutics, 11th Edition (McGraw-Hill, 2006); and Remington: The Science and Practice of Pharmacy, 22nd Edition, (Pharmaceutical Press, London, 2012)). The amount of binding agent may vary according to factors such as the disease state, age, sex, and weight of the individual, and the ability of the binding agent to elicit a desired response in the individual. For example, a therapeutically effective amount of a binding agent of the invention is an amount induces clearance of the pathogenic aggregated form of Aβ peptide in Alzheimer’s disease.

[0108] A typical dose can be, for example, in the range of 1 pg / kg to 20 mg / kg of animal or human body weight; however, doses below or above this exemplary range are within the scope of the invention. The daily parenteral dose can be about 0.00001 μg / kg to about 20 mg / kg of total body weight (e.g., about 0.001 μg / kg, about 0.1 μg / kg , about 1 μg / kg, about 5 μg / kg, about 10 μg / kg, about 100 μg / kg, about 500 μg / kg, about 1 mg / kg, about 5 mg / kg, about 10 mg / kg, or a range defined by any two of the foregoing values), preferably from about 0.1 μg / kg to about 10 mg / kg of total body weight (e.g., about 0.5 μg / kg, about 1 μg / kg, about 50 μg / kg, about 150 μg / kg, about 300 μg / kg, about 750 μg / kg, about 1.5 mg / kg, about 5 mg / kg, or a range defined by any two of the foregoing values), more preferably from about 1 μg / kg to 5 mg / kg of total body weight (e.g., about 3 μg / kg, about 15 μg / kg, about 75 μg / kg, about 300 μg / kg, about 900 μg / kg, about 2 mg / kg, about 4 mg / kg, or a range defined by any two of the foregoing values), and even more preferably from about 0.5 to 15 mg / kg bodyLeydig 774215 37 weight per day (e.g., about 1 mg / kg, about 2.5 mg / kg, about 3 mg / kg, about 6 mg / kg, about 9 mg / kg, about 11 mg / kg, about 13 mg / kg, or a range defined by any two of the foregoing values). Therapeutic or preventative efficacy can be monitored by periodic assessment of treated patients. For repeated administrations over several days or longer, depending on the condition, the treatment can be repeated until a desired suppression of disease symptoms occurs. However, other dosage regimens may be useful and are within the scope of the invention. The desired dosage can be delivered by a single bolus administration of the composition, by multiple bolus administrations of the composition, or by continuous infusion administration of the composition.

[0109] In some embodiments, the disease, disorder, or condition is Alzheimer’s disease. As used herein the term “Alzheimer’s disease” or “AD” refer to any form of Alzheimer’s disease, including but not limited to familial Alzheimer’s disease (FAD).

[0110] The invention also provides a method for inducing clearance of an aggregated form of amyloid-beta (Aβ) peptide in a mammal, the method comprising administering the described binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide, or the described composition, to the mammal. The administration can be via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection. In some embodiments, the administration is via intravenous injection. In some embodiments, the administration is via subcutaneous injection. In some embodiments, the mammal is a human.

[0111] As used herein, the term “clearance” refers to any reduction in the amount of pathogenic aggregated form of amyloid-beta (Aβ) peptide in a mammal. In some embodiments clearance is induced by promoting antibody dependent cell-mediated phagocytosis (ADCP).

[0112] The invention also provides a hybridoma or cell line that expresses a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein.

[0113] The invention also provides a method of diagnosing Alzheimer’s disease in a mammal, the method comprising (1) taking a biological sample of the mammal, (2) contacting the sample with a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein, (3) measuring the concentration of complexes formed of the sample and a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide described herein, and (4) comparing the concentration of complexes to a reference value.

[0114] As used herein, a “biological sample” refers to a sample derived from a mammal. In some embodiments, the biological sample can be a body fluid or a cell or tissue extract.Leydig 774215 38 Examples of biological samples include, but are not limited to, blood, plasma, serum, cerebrospinal fluid (CSF), or a biopsied tissue. Any method known in the art for taking a biological sample that preserves the integrity of the aggregated form of Aβ peptide may be employed in the context of the invention.

[0115] Aggregated form of amyloid-beta (Aβ) peptide levels can be measured as the concentration of complexes formed of the sample and the described binding agent by any suitable method known in the art. Such methods include, for example, immunohistochemistry, immunofluorescence, radioimmunoassay (RIA), and FACS. Normal or standard expression values aggregated form of amyloid-beta (Aβ) peptide can be established using any suitable technique, e.g., by combining a sample comprising, or suspected of comprising, an aggregated form of amyloid-beta (Aβ) peptide with an aggregated form of amyloid-beta (Aβ) peptide specific antibody under conditions suitable to form an antigen-antibody complex. The binding agent can be used with or without modification, such as covalent or non-covalent labeling with a detectable moiety. For example, the detectable moiety can be a radioisotope (e.g., 3H, 14C, 32P, 35S, or 125I), a fluorescent or chemiluminescent compound (e.g., fluorescein isothiocyanate, rhodamine, or luciferin), an enzyme (e.g., alkaline phosphatase, beta-galactosidase, or horseradish peroxidase), or prosthetic groups. Any method known in the art for separately conjugating an antigen-binding agent (e.g., an antibody) to a detectable moiety may be employed in the context of the invention (see, e.g., Hunter et al., Nature, 194:495-496 (1962); David et al., Biochemistry, 13:1014-1021 (1974); Pain et al., J. Immunol. Meth., 40:219-230 (1981); and Nygren, J. Histochem. and Cytochem., 30:407-412 (1982)). The antibody is directly or indirectly labeled with a detectable substance to facilitate detection of the bound or unbound antibody. Suitable detectable substances include various enzymes, prosthetic groups, fluorescent materials, luminescent materials, and radioactive materials (see, e.g., Zola, Monoclonal Antibodies: A Manual of Techniques, CRC Press, Inc. (1987)). In a similar manner, the binding agent can be used in an assay to monitor aggregated form of amyloid- beta (Aβ) peptide levels in a subject being tested for a disease or disorder that is associated with abnormal aggregated form of amyloid-beta (Aβ) peptide levels.

[0116] The reference value used for comparison with the concentration of complexes formed of aggregated form of amyloid-beta (Aβ) peptide expressed in a sample and the described binding agent will vary depending on the sample. In some embodiments the reference sample can be from a patient diagnosed with Alzheimer’s disease.Leydig 774215 39

[0117] Aspects, including embodiments, of the invention described herein may be beneficial alone or in combination, with one or more other aspects or embodiments. Without limiting the foregoing description, certain non-limiting aspects of the disclosure numbered 1-61 are provided below. As will be apparent to those of skill in the art upon reading this disclosure, each of the individually numbered aspects may be used or combined with any of the preceding or following individually numbered aspects. This is intended to provide support for all such combinations of aspects and is not limited to combinations of aspects explicitly provided below:

[0118] (1) In aspect (1) is provided a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide and an immunoglobulin light chain variable region polypeptide, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22 and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23-42 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62 and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences of KVS, WAS, KVF, or any one of SEQ ID NOs: 83-102 and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122 and 275.

[0119] (2) In aspect (2) is provided a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317 or at least the CDRs thereof.

[0120] (3) In aspect (3) is provided a binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-142, 163-178, 195-210, 227-242, 276-286, and 298-307 and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90%Leydig 774215 40 identical to any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317.

[0121] (4) In aspect (4) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23- 42, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82, a complementarity determining region 2 (LCDR2) comprising any one of SEQ ID NOs: 83- 102, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122.

[0122] (5) In aspect (5) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23- 42, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences of KVS, WAS, KVF, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122.

[0123] (6) In aspect (6) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 2, comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123-142, or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, or at least the CDRs thereof.

[0124] (7) In aspect (7) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 3, comprising an immunoglobulin heavy chain variableLeydig 774215 41 region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-142, and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 143-162.

[0125] (8) In aspect (8) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 6, 16, and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 26 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43, 46, and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 66 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of SEQ ID NOs: 86, 88, and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 106 and 275.

[0126] (9) In aspect (9) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 6, 16, and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 26 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43, 46, and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 66 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS and KVF, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 106 and 275.

[0127] (10) In aspect (10) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 2, comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 276-286 and 298-307, or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 287-297 and 308-317, or at least the CDRs thereof.Leydig 774215 42

[0128] (11) In aspect (11) is provided the binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of aspect 3, comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 276-286 and 298-307, and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 287-297 and 308-317.

[0129] (12) In aspect (12) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-3, which comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of SEQ ID NO: 83, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of SEQ ID NO: 84, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of SEQ ID NO: 85, and the LCDR3 of SEQ ID NO: 105; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of SEQ ID NO: 87, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 108; the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of SEQ ID NO: 89, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO: 110;Leydig 774215 43 the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of SEQ ID NO: 91, and the LCDR3 of SEQ ID NO: 111; the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of SEQ ID NO: 92, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of SEQ ID NO: 93, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of SEQ ID NO: 94, and the LCDR3 of SEQ ID NO: 114; the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of SEQ ID NO: 95, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of SEQ ID NO: 96, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO: 117; the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of SEQ ID NO: 98, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of SEQ ID NO: 99, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of SEQ ID NO: 100, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of SEQ ID NO: 101, and the LCDR3 of SEQ ID NO: 121; orLeydig 774215 44 the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of SEQ ID NO: 102, and the LCDR3 of SEQ ID NO: 122.

[0130] (13) In aspect (13) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-3, which comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of the amino acid sequence WAS, and the LCDR3 of SEQ ID NO: 105; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 108; the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of the amino acid sequence KVF, and the LCDR3 of SEQ ID NO: 110; the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 111;Leydig 774215 45 the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 114; the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 117; the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 121; or the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 122.Leydig 774215 46

[0131] (14) In aspect (14) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-3, which comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 273, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 274, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 47 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 275.Leydig 774215 48

[0132] (14) In aspect (14) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-3, which comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 273, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 274, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 49 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 275.Leydig 774215 50

[0133] (15) In aspect (15) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-3, which comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVF, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 51 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 275.Leydig 774215 52

[0134] (16) In aspect (16) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-15, wherein the binding agent is an antibody or an antigen-binding fragment thereof.

[0135] (17) In aspect (17) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 16, wherein the binding agent is an antibody fragment selected from F(ab’)2, Fab’, Fab, Fv, scFv, dsFv, dAb, and a single chain binding polypeptide.

[0136] (18) In aspect (18) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 16, wherein the binding agent is an antibody.

[0137] (19) In aspect (19) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 18, wherein the antibody is an IgG, IgM, IgA, IgD or IgE antibody.

[0138] (20) In aspect (20) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 18 or aspect 19, wherein the antibody is an IgG antibody.

[0139] (21) In aspect (27) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 18-20 wherein the antibody is humanized.

[0140] (22) In aspect (22) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 20 or aspect 21, comprising the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106.

[0141] (23) In aspect (23) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 22, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 163 and 179, SEQ ID NOs: 164 and 180, SEQ ID NOs: 165 and 181, SEQ ID NOs: 166 and 182, SEQ ID NOs: 167 and 183, SEQ ID NOs: 168 and 184, SEQ ID NOs: 169 and 185, SEQ ID NOs: 170 and 186, SEQ ID NOs: 171 and 187, SEQ ID NOs: 172 and 188, SEQ ID NOs: 173 and 189, SEQ ID NOs: 174 and 190, SEQ ID NOs: 175 and 191, SEQ ID NOs: 176 and 192, SEQ ID NOs: 177 and 193, or SEQ ID NOs: 178 and 194.

[0142] (24) In aspect (24) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 20 or aspect 21, comprising the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO: 110.Leydig 774215 53

[0143] (25) In aspect (25) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 24, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 195 and 211, SEQ ID NOs: 196 and 212, SEQ ID NOs: 197 and 213, SEQ ID NOs: 198 and 214, SEQ ID NOs: 199 and 215, SEQ ID NOs: 200 and 216, SEQ ID NOs: 201 and 217, SEQ ID NOs: 202 and 218, SEQ ID NOs: 203 and 219, SEQ ID NOs: 204 and 220, SEQ ID NOs: 205 and 221, SEQ ID NOs: 206 and 222, SEQ ID NOs: 207 and 223, SEQ ID NOs: 208 and 224, SEQ ID NOs: 209 and 225, or SEQ ID NOs: 210 and 226.

[0144] (26) In aspect (26) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 20 or aspect 21, comprising the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO: 117.

[0145] (27) In aspect (27) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 26, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 227 and 243, SEQ ID NOs: 228 and 244, SEQ ID NOs: 229 and 245, SEQ ID NOs: 230 and 246, SEQ ID NOs: 231 and 247, SEQ ID NOs: 232 and 248, SEQ ID NOs: 233 and 249, SEQ ID NOs: 234 and 250, SEQ ID NOs: 235 and 251, SEQ ID NOs: 236 and 252, SEQ ID NOs: 237 and 253, SEQ ID NOs: 238 and 254, SEQ ID NOs: 239 and 255, SEQ ID NOs: 240 and 256, SEQ ID NOs: 241 and 257, or SEQ ID NOs: 242 and 258.

[0146] (28) In aspect (28) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-27, wherein the binding agent is, or is part of, a multispecific or bispecific antibody, chimeric antigen receptor, chimeric T cell receptor, bispecific T-cell engager, multivalent antibody, diabody, triabody, tetrabody, hexabody, bis-scFv fragment, Fab dimer, or Fab trimer.

[0147] (29) In aspect (29) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-28, comprising at least one additional Aβ binding domain fused to the binding agent, wherein the binding agent has more than two binding domains per molecule and a higher avidity of binding to sAβ aggregates compared to the binding agent without at least one additional Aβ binding domain fused to the binding agent.Leydig 774215 54

[0148] (30) In aspect (30) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-29, wherein the binding agent is conjugated to a blood-brain barrier (BBB) shuttle moiety.

[0149] (31) In aspect (31) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 30, wherein the BBB shuttle moiety is a binding agent targeted to a transferrin receptor (TfR).

[0150] (32) In aspect (32) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of aspect 31, wherein the BBB shuttle moiety is an antibody or an antigen-binding fragment thereof.

[0151] (33) In aspect (33) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, wherein the binding agent is an antibody conjugate.

[0152] (34) In aspect (34) is provided a nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1- 32.

[0153] (35) In aspect (35) is provided a vector comprising the nucleic acid of aspect 34.

[0154] (36) In aspect (36) is provided an isolated cell comprising the nucleic acid of aspect 34 or the vector of aspect 35.

[0155] (37) In aspect (37) is provided a method of providing the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, the method comprising expressing in a cell in vitro one or more nucleic acids encoding the immunoglobulin heavy and light chain polypeptides thereof.

[0156] (38) In aspect (38) is provided a composition comprising the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, the nucleic acid of aspect 34, or the vector of aspect 35, and a pharmaceutically acceptable carrier.

[0157] (39) In aspect (39) is provided the composition of aspect 38 wherein the composition is formulated for nasal administration, intravenous injection, subcutaneous injection, or intraperitoneal injection.

[0158] (40) In aspect (40) is provided the composition of aspect 38 or aspect 39, wherein the composition is formulated for intravenous injection.Leydig 774215 55

[0159] (41) In aspect (41) is provided the composition of aspect 38 or aspect 39, wherein the composition is formulated for subcutaneous injection.

[0160] (42) In aspect (42) is provided the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, or the composition of any one of aspects 38-41, for use as a medicament for treating a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance.

[0161] (43) In aspect (43) is provided the use of aspect 42, wherein the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition.

[0162] (44) In aspect (44) is provided the use of aspect 43, wherein the neurodegenerative disease, disorder, or condition is Alzheimer’s disease.

[0163] (45) In aspect (45) is provided the use of aspect 43, wherein the neurodegenerative disease, disorder, or condition is Down’s syndrome.

[0164] (46) In aspect (46) is provided the use of aspect 42, where the disease, disorder, or condition is characterized by ocular deposition of aggregated Aβ.

[0165] (47) In aspect (47) is provided the use of aspect 42, where the disease, disorder, or condition is characterized by deposition of aggregated Aβ outside the central nervous system.

[0166] (48) In aspect (48) is provided a method for treating or preventing a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance, the method comprising administering the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, or the composition of any one of aspects 38-41, to the mammal.

[0167] (49) In aspect (49) is provided the method of aspect 48, wherein the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition.

[0168] (50) In aspect (50) is provided the method of aspect 49, wherein the neurodegenerative disease, disorder, or condition is Alzheimer’s disease.

[0169] (51) In aspect (51) is provided the method of aspect 49, wherein the neurodegenerative disease, disorder, or condition is Down’s syndrome.

[0170] (52) In aspect (52) is provided the method of aspect 48, where the disease, disorder, or condition is characterized by ocular deposition of aggregated Aβ.

[0171] (53) In aspect (53) is provided the method of aspect 48, where the disease, disorder, or condition is characterized by deposition of aggregated Aβ outside the central nervous system.Leydig 774215 56

[0172] (54) In aspect (54) is provided the method of any one of aspects 48-53, wherein the administration is via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection.

[0173] (55) In aspect (55) is provided the method of any one of aspects 48-54 wherein the administration is via intravenous injection.

[0174] (56) In aspect (56) is provided the method of any one of aspects 48-54, wherein the administration is via subcutaneous injection.

[0175] (57) In aspect (57) is provided the method of any one of aspects 48-56, wherein the mammal is a human.

[0176] (58) In aspect (58) is provided a method for inducing clearance of an aggregated form of amyloid-beta (Aβ) peptide in a mammal, the method comprising administering the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, or the composition of any one of aspects 38-41, to the mammal.

[0177] (59) In aspect (59) is provided the method of aspect 58, wherein the administration is via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection.

[0178] (60) In aspect (60) is provided the method of aspect 58 or aspect 59, wherein the administration is via intravenous injection.

[0179] (61) In aspect (61) is provided the method of aspect 58 or aspect 59, wherein the administration is via subcutaneous injection.

[0180] (62) In aspect (62) is provided the method of any one of aspects 58-61, wherein the mammal is a human.

[0181] (63) In aspect (63) is provided a hybridoma or cell line that expresses the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1- 32.

[0182] (64) In aspect (64) is provided a method of diagnosing Alzheimer’s disease in a mammal, the method comprising: (1) taking a biological sample of the mammal, (2) contacting the sample with the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-32, (3) measuring the concentration of complexes formed of the sample and the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of aspects 1-30, and comparing the concentration of complexes to a reference value.Leydig 774215 57

[0183] The following examples further illustrate the invention but, of course, should not be construed as in any way limiting its scope. EXAMPLES

[0184] The following examples describe the discovery of binding agents targeted to an aggregated form of amyloid-beta (Aβ) peptides through a rigorous screening process to identify candidates with optimal binding characteristics from a pool of over 500 million splenocytes from immunized mice.

[0185] The examples also highlight several desirable properties, both singularly and in combination, with potential advantages of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein over existing binding agents. The selective targeting of pathogenic Aβ aggregates by the binding agents described herein directly addresses the disease-relevant species involved in AD pathogenesis, potentially leading to reduced off-target binding and better outcomes. The examples show that the binding agents described herein exhibit strong binding affinity for sAβ aggregates and fibrils compared to other Aβ binding agents, enhancing their potential for therapeutic efficacy and possibly more tolerable delivery to patients. The examples also demonstrate through in vitro studies the ability of the binding agents described herein to potently confer increased uptake by microglial cells compared to reference antibodies, and therefore induce clearance of Aβ aggregates.

[0186] The following methods were carried out in connection with the examples. Soluble Aβ (sAβ) aggregates preparation

[0187] Unconjugated synthetic wild-type Aβ1-42 peptide, whose purity was ≥95% by high performance liquid chromatography (HPLC), was purchased from Anaspec Inc. (San Jose, CA, USA). The lyophilized Aβ1-42 peptide was reconstituted with 10 mM NaOH (pH11) to the concentration between 300 and 600 µM. The peptide powder was dissolved with brief vortexing and sonication in sonication bath (Söderberg et al., “Lecanemab, Aducanumab, and Gantenerumab - Binding Profiles to Different Forms of Amyloid-Beta Might Explain Efficacy and Side Effects in Clinical Trials for Alzheimer's Disease,” Neurotherapeutics, 20(1):195-206, (January 2023)). sAβ aggregates were prepared by mixing one part of 4XPBS (200 mM sodium phosphate, 600 mM NaCl, pH7.4) and three parts of the peptide solution and incubating the mixture at 37°C for 40 - 50 minutes, depending on theLeydig 774215 58 concentration of the peptide. The sAβ aggregates were separated from insoluble Aβ fibrils by centrifugation at 4°C for 10 min and further purified through size exclusion chromatography (SEC) using Superdex 7510 / 300 (Cytiva). sAβ aggregates were eluted from the Superdex column. The purity of the sAβ aggregates was assessed by HPLC with a Superdex 753.2 / 100 column (Cytiva) in buffer consisting of 50 mM Na-phosphate (pH 7.4), 150 mM NaCl, and 0.5 % Tween-20 at the flow rate of 80 µl / min. sAβ aggregates were eluted at 11-12 minutes. The purified human sAβ aggregates were at least 95 % pure and not contaminated by other Aβ conformational form (FIG.1A and Table 1A). Aβ1-40 monomer was purified through the same method as sAβ aggregates purification without the incubation at 37°C. The Aβ1-40 monomer was eluted from the Superdex 75 Increase 10 / 300 column between 18 ml and 19 ml of elution. Then, the purity of the Aβ1-40 monomer was assessed by HPLC with a Superdex 753.2 / 100 column (Cytiva) in buffer consisting of 50 mM Na-phosphate (pH7.4), 150 mM NaCl, and 0.5 % Tween-20 at the flow rate of 80 µl / min. Aβ 1-40 monomer was eluted at 19- 20 minutes. The prepared Aβ 1-40 monomer was at least 95 % pure (FIG.1B and Table 1B).

[0188] In Table 1A and Table 1B BB refers to baseline-to-baseline; VV refers to valley- to-valley; VB refers to valley-to-baseline; and BV refers to baseline-to-valley. Table 1A # Time Type Area Height Width Area% SymmetryTable 1B # Time Type Area Height Width Area% SymmetryLeydig 774215 59 Mouse immunization

[0189] Balb / C mice were immunized with sAβ aggregate preparation. The procedure used to immunize mice was a standard protocol involving intraperitoneal (i. p.) injections of sAβ aggregates in the presence of Freund’s adjuvant. Each animal was initially immunized with 30 µg sAβ aggregate and subsequently boosted with 15 µg of sAβ aggregates for 5 times. The sAβ aggregate antigen was mixed 1:1 with Freund’s complete adjuvant prior to the first injection. For subsequent 5 booster injections incomplete Freund’s adjuvant was used. Mice were bled and blood collected for antibody titer determinations by ELISA. Mice were sacrificed and the spleen cells, PBMC, and lymph node cells were collected for antibody discovery. Anti-sAβ aggregate Antibody Discovery

[0190] The binding agent discovery method used for isolation and initial characterization of antibodies described herein is shown in FIG.2. Isolated B cells were stained with a fluorophore-conjugated sAβ aggregate probe to identify sAβ aggregates-specific B cells. Stained B cells were subsequently sorted using fluorescence-activated cell sorting (FACS) at one cell per well into PCR plates (VWR, catalog number: 211-0297). Single B cells in PCR plates underwent reverse transcription to generate cDNA. Overhang primers were employed to amplify the variable regions of the heavy and kappa genes and add homologous sequences for downstream generation of linear expression cassettes (LECs). LECs were transfected into Expi293F cells in 96-well culture blocks using Expifectamine (Thermo Fisher, catalog number: A14525). Transfected cells were cultured and allowed to express the antibody for five to seven days. The expression yields were determined by IgG enzyme-linked immunosorbent assay (ELISA) (Thermo Fisher, catalog number: 88-50550-22). The unpurified expression supernatant from each well was diluted to concentrations of 100 ng / mL, 10 ng / mL, and 1 ng / mL. These dilutions were used in a sAβ aggregates direct ELISA to screen for antibody binding activity. Clones demonstrating strong signals in the initial screening were selected for further analysis. Variable regions of the selected clones were sequenced using the LEC clone inserts. Expression plasmids were then generated to express and purify the antibodies for in-depth functional and binding studies.Leydig 774215 60 Recombinant antibody construction and production

[0191] Antibody variable fragment genes were cloned into mammalian expression vectors for expression of antibodies. Antibody variable heavy chains were cloned into a pcDNA plasmid vector with built-in human IgG1 constant sequence (SEQ ID NO: 1) (including CH1, CH2 and CH3), and antibody variable light chains were cloned into a pcDNA plasmid vector with built-in human kappa light chain constant sequence (SEQ ID NO: 2), shown in Table 2. Cloning was done by standard molecular engineering methods that include digestion of the vector and antibody variable fragments with restriction enzymes and ligation of the vector with the antibody fragments, or Gibson assembly of the vector with the fragments. The expression vector plasmids contain necessary expression and regulatory elements for transcription and translation of antibody genes. Table 2. Human IgG1 heavy chain and kappa light chain constant sequences Human SEQ ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWN IgG1 ID SGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNV P N V V

[0192] Plasmids with cloned antibody variable heavy chain sequences and variable light chain sequences were co-transfected together into mammalian cells, such as CHO or HEK293 or Expi293 cells, using Polyethylenimine HCl MAX as a carrier. The mammalian cells were cultured in a cell culture shaker for 5-7 days at 37°C with supply of 8% CO2 and 80% humidity. Antibodies expressed in the culture supernatants were thereafter purified using Protein A column chromatography. Antibodies bound to protein A in the columns were eluted using acidic glycine buffer (pH2-2.5), neutralized with basic Tris buffer (pH8.0), and proceeded for buffer exchange using phosphate buffered saline (PBS) pH7.2. The purity of the antibodies was analyzed with SDS-PAGE and size-exclusion HPLC.Leydig 774215 61 Screening of sAβ aggregate specific antibody by ELISA

[0193] For Aβ ELISA, plates and reagents were kept strictly at 4°C leading up to and during coating and competition steps. Subsequent steps were done at room temperature. Molar concentrations of Aβ monomer and sAβ aggregates are based on the Aβ monomeric peptide. Protocols were modified from previously published work (Englund, et al., “Sensitive ELISA detection of amyloid‐β sAβ aggregates in biological samples,” Journal of Neurochemistry, 103(1):334-345, (2007) and Jin, et al., “An in vitro paradigm to assess potential anti-Aβ antibodies for Alzheimer’s disease,” Nature Communications, 9(1):2676, (2018)). Aβ Direct ELISA

[0194] High binding plates (R&D Systems, catalog number: DY990) were coated with Aβ monomer or sAβ aggregates in 100µL PBS (Fisher Scientific, catalog number: SH30256LS) at a concentration of 25 ng / mL. Plates were coated at 4°C for 2 hours, washed with wash buffer (PBS with 0.05% Tween 20 (Sigma-Aldrich, catalog number: P9416)), blocked with 270 µL 2% BSA (Sigma-Aldrich, catalog number: A3059) for one hour and washed with wash buffer. Antibody samples were added in 100 µL and incubated for 1 hour and washed with wash buffer. Anti-human IgG HRP (Thermo Fisher, catalog number: 31413) secondaries were diluted at 1:10,000, added in 100µL, and incubated for 45 minutes. Antibody samples and secondary antibodies were diluted in 0.5% BSA.100 µL TMB substrate (Thermo Fisher, catalog number: N301) was added for exactly 10 minutes before being stopped with 40 µL 2.5M sulfuric acid (Millipore Sigma, catalog number: 1099120001). The absorbance (OD) was measured with a standard plate reader at 450 nm. In general, test antibodies were measured at 10-fold dilutions from 10 to 0.0001µg / mL. Samples were tested with controls of sAβ aggregates-coated wells with no test antibody, or non-Aβ- coated wells, and blocked wells with 1µg / mL test antibody. High throughput LEC supernatant ELISA primary screenings followed the same protocol but were done in a narrower concentration range with fewer controls, and promising candidates were later confirmed more extensively. Aβ Competition ELISA

[0195] For competition ELISA, plates were coated with sAβ aggregates, blocked, and washed as described above. In a separate, low-binding assay plate (Millipore Sigma, catalogLeydig 774215 62 number: P-96-450V-C-S), 1 ng of test antibody was added to each well in 10 µL (100 ng / mL stock antibody). Then, a dilution series of Aβ (sAβ aggregates or monomer) was added to the 1 ng of antibody in 90 µL (antibody final concentration 10 ng / mL). Aβ and antibody were allowed to incubate at 4°C for 1 hour. This mixture was then directly added to the coated, blocked ELISA plate and incubated for 20 minutes at room temperature. Subsequent secondary antibody addition, substrate development, and measurement were completed as described above. Data were plotted as percentage of maximum signal. The max signal was set as the signal with 10 ng / mL antibody and no Aβ, and the background signal was OD=0.05. The calculation was: ((sample – background) / (max – background))*100%. At 10 ng / mL of antibody, the fragment antigen-binding regions (fabs) are present at approximately 133 picomolar. This is assumed to be the lower IC50 limit of detection of the assay, where the concentration of fabs is equal to the concentration of Aβ peptide. Binding kinetics measurement

[0196] The binding kinetics of anti-Aβ antibody to various species of Aβ was measured by bio-Layer Interferometry (BLI) using Octet Red (Sartorius). To measure the binding kinetics to sAβ aggregates, N-terminally biotinylated sAβ aggregates (sAβ-agg-Biot) captured on SA Biosensors (Sartorius). Then, the sAβ-agg-Biot captured Biosensors were dipped into the solutions containing anti-Aβ antibody, whose concentrations were 2-fold serially diluted, starting from 40 nM. For each assay, the association and dissociation of the antibody were monitored for 200 sec and 400 sec, respectively. The assay was performed at 25°C in PBST-BSA buffer containing 0.1 % Tween-20 and BSA. The data was analyzed with Octet Analysis Studio 12.2 (Sartorius) and fit to 1:1 binding model to derive Kon, Koff, and dissociation constant KD.

[0197] The Octet assay was used to screen anti-Aβ antibodies that bind to sAβ aggregates with high affinity. In the Octet assays, Lecanemab (DrugBank Entry for DB accession number: DB14580, Lecanemab, pgs.1-8, Source: DrugBank Online, Modify Date: July 18, 2023 [online database], [retrieved on June 21, 2024]) or H2731 (United States Published Patent Application No.20220041700 (Skov et al., 2022)) were included as reference anti-Aβ antibodies.Leydig 774215 63 Immunofluorescent staining of human AD brain tissue

[0198] Unfixed, frozen brain tissue specimens from human donors with AD (Braak stage IV – VI) were cryosectioned at a thickness of 10 µm, and thaw-mounted on 12 mm diameter 1.5 poly-L-lysine coated coverslips. Prior to immunofluorescence staining, serial brain sections were washed with PBS to remove Optimal Cutting Temperature compound (OCT), and then incubated with anti-Aβ or human isotype control antibodies for 1 hour at 37°C. Sections were then washed, fixed using 4% paraformaldehyde, and incubated with Alexa Fluor conjugated anti-human secondary antibody (Invitrogen) for one hour at room temperature. Following immunostaining, tissue sections were stained using Amylo-glo (Biosensis) according to the manufacturer’s protocol and mounted using Prolong Glass Antifade Mountant (Thermo Fisher Scientific). Immunofluorescence imaging was performed using the Keyence BZ-X800 microscope. Z-stacks were acquired at 40x magnification, using at a 0.5 um pitch and range of 10 um, and merged to produce maximum intensity projections. Cell line and iMGL differentiation

[0199] The GM23338 iPSC line from Coriell Institute was differentiated into hematopoietic progenitor cells (HPCs) using the STEMdiff Hematopoietic Kit from Stemcell Technologies according to the manufacturer’s protocol and were cryopreserved prior to differentiation into iPSC-derived microglia-like cells (iMGLs). Approximately one month prior to phagocytosis assays, HPCs were recovered and differentiated into iMGLs as previously described (Abud, et al., “iPSC-Derived Human Microglia-like Cells to Study Neurological Diseases,” Neuron, 94(2):278-293 (April 2017)) and used for experimentation from 28-33 days after recovery. In vitro phagocytosis assay

[0200] One hour prior to the phagocytosis assay, iMGL were treated with 100 nM Bafilomycin A1 to prevent lysosomal degradation of phagocytosed contents, and APC- labeled sAβ aggregates were pre-incubated with anti-Aβ or isotype control antibodies at 4°C in assay medium. To begin the assay, iMGL medium was replaced with the pre-incubated antibody and sAβ aggregate solution, and phagocytosis was allowed to proceed for 2 hours at 37°C. Cells were then harvested, and mean APC fluorescence was determined using flow cytometry.Leydig 774215 64 Ex vivo phagocytosis assay

[0201] Unfixed hAβSAA knock-in (APP-SAA) (The Jackson Laboratory) mouse brains were coronally cryosectioned at a thickness of 10 µm, and thaw-mounted on 12 mm diameter 1.5 poly-L-lysine coated coverslips. Serial brain sections were washed with PBS to remove OCT, and then preincubated with antibody for 1 hour at 37°C. Sections were then washed to remove unbound antibody, and iMGLs were added to tissue sections in assay media. Cultures were maintained at 37°C for 24 hours, then were washed and either fixed with 4% paraformaldehyde, or stored at -80°C. Immunofluorescence imaging of amyloid plaques

[0202] Evaluation of amyloid plaques following iMGL phagocytosis was assessed using immunofluorescent Aβ staining. Briefly, fixed brain tissue sections were washed in PBS, permeabilized, and then blocked in 5% normal goat serum. Sections were then incubated with anti-APP clone 6E10 antibody (Novus Biologicals), followed by Alexa Fluor conjugated anti- human and anti-rabbit IgG antibodies (Invitrogen). Following immunostaining, tissue sections were stained using Amylo-glo (Biosensis) according to the manufacturer’s protocol and mounted using Prolong Glass Antifade Mountant (Thermo Fisher Scientific). Immunofluorescence imaging was performed using the Keyence BZ-X800 microscope. Z- stacks were acquired at 40x magnification, using at a 0.5 µm pitch and range of 10 µm, and merged to produce a maximum intensity projection. Humanization of mouse anti-Aβ antibodies

[0203] Humanization of mouse anti-Aβ antibodies were performed by CDR grafting. Briefly, the original mouse sequences were aligned to all human germline sequences. The original mouse and closest matching germline sequences were analyzed, and the most appropriate germline frameworks were selected. Molecular models were built for VH and VL domains based on homology to previously published antibody crystal structures. Complementarity determining regions (CDRs) from the parent mouse antibodies were grafted onto the human frameworks, antibody sequences were analyzed for specific liabilities based on published protein motifs and back mutations introduced as necessary to maintain proper folding and binding property. The humanized heavy chain variable and light chain variable sequences were cloned into pcDNA3.1 vector with the human IgG1 constant sequence (SEQ ID NO: 1) and human kappa constant sequence (SEQ ID NO: 2).Leydig 774215 65 EXAMPLE 1

[0204] This example demonstrates the discovery of novel binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein by screening for the binding strength of the binding agents to sAβ aggregates.

[0205] B cells isolated from sAβ aggregate immunized mice were sorted into 96-well plate using FACS. Linear expression cassettes (LECs) that include all necessary mammalian expression components were produced through 3 rounds of PCR, and the LECs were transfected into Expi293F cells to produce antibodies, which were used in a direct ELISA to measure the binding strength of the antibodies to sAβ aggregates. Direct ELISA on sAβ aggregate-coated plates was performed for initial screening of expressed antibodies in non- purified supernatant from cultures transfected with LEC in high throughput. The antibodies 1A3, 1A5, 1G8, 1H2, 1B9, 2D8, and 2A10 were tested in rounds 1 and 2 (FIG.3A), the antibodies 3C6, 3B8, 3E8, 3E10, and 3E2 were tested in round 3 (FIG.3B), the antibodies 4D11, 4A10, 4B2, 5H1, 4E1, and 4C10 were tested in rounds 4 and 5 (FIG.3C). ELISA for each round was completed with Lecanemab as a reference antibody. The binding strength of the antibodies were compared to the reference antibody Lecanemab (DrugBank Entry for DB accession number: DB14580, Lecanemab, pgs.1-8, Source: DrugBank Online, Modify Date: July 18, 2023 [online database], [retrieved on June 21, 2024]). After 5 rounds of screenings the antibody clones that had stronger binding than Lecanemab, antibodies 1A3, 1A5, 1G8, 1H2, 1B9, 3C6, 3B8, 3E8, 3E10, 3E2, 4D11, 4A10, 4B2, 5H1, 4E1, and 4C10, were selected for sequencing and further characterization.

[0206] LEC fragments from the selected mouse antibody clones were sequenced to obtain the heavy and light chain variable sequences. The CDRs and full amino acid sequences of heavy and light chain variable regions were listed in Table 3, Table 4, Table 5, and Table 6. Additional residues that are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are underlined in Table 3, Table 4, Table 5, and Table 6. In Table 5 and Table 6 CDRs as defined by IMGT notation are shown in bold with no underline.Leydig 774215 66 Table 3. CDR sequences of the heavy chain variable regions Bindin SEQ SEQ SEQ g Agent ID CDRH1 ID CDRH2 ID CDRH3 Y YLeydig 774215 67 Table 4. CDR sequences of the light chain variable regions Binding SEQ ID SEQ SEQ Agent NO. CDRL1 ID CDRL2 ID CDRL3 T T T T Y T T T T T T T T T T T T T T TLeydig 774215 68 Table 5. The amino acid sequences of the full heavy chain variable regions (mouse) Binding SEQ Heavy Chain Variable Region Sequence Agent ID G R G L G T G L G R E R LS G R G R K T G L G RLeydig 774215 69 Binding SEQ Heavy Chain Variable Region Sequence Agent ID G L G L G L G D G R G R G S G LLeydig 774215 70 Table 6. The amino acid sequences of the full light chain variable regions (mouse) Bindin SEQ Light Chain Variable Region Sequence g ID A t NO L L Q L L Q L Q L L L K G L L LLeydig 774215 71 Bindin SEQ Light Chain Variable Region Sequence g ID A nt NO L K G K G L L K G LEXAMPLE 2

[0207] This example demonstrates the binding characteristics of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein compared to Lecanemab and H2731.

[0208] The selected mouse sequences of heavy and light chain variable regions were cloned into mammalian expression plasmid pcDNA3.1 with human IgG1 Fc sequence and transfected into CHO cells for chimeric recombinant antibody production. The purified chimeric recombinant antibodies were used to measure binding to sAβ aggregates or Aβ monomers.

[0209] The binding activity of the purified recombinant chimeric antibodies to sAβ aggregate or Aβ monomer was measured by direct ELISA with plates coated with sAβ aggregate (FIGs.4A-4C, top graph) or Aβ monomer (FIGs.4A-4C, bottom graph). The binding activity of antibodies 1A3, 1G8, 1A5, 1B9, 1H2, 2A10, and 2D8 were tested in rounds 1 and 2 and compared with reference antibody Lecanemab (FIG.4A). The bindingLeydig 774215 72 activity of antibodies 3E8, 3B8, 3C6, 3E10, and 3E2 were tested in round 3 (FIG.4B) and the binding activity of antibodies H1G8_K1A3, 4A10_M1, 4D11, 4A10, 4B2, and 4E1 were tested in round 4 (FIG.4C) and were compared side-by-side with reference antibodies Lecanemab and H2731. Antibodies that bind strongly to sAβ aggregates and weakly to Aβ monomers compared to reference antibodies, antibodies 1A3, 1G8, 4B2, 3E8, 3B8, 4A10_M1, and 4D11, were selected for further characterization.

[0210] The binding activity of the recombinant antibodies 3B8 (FIG.5C), 4B2 (FIG.5D), 3E8 (FIG.5E), 4D11 (FIG.5F), 1G8 (FIG.5G), 4A10_M1 (FIG.5H), and H1G8_K1A3 (FIG.5I), were further measured by competition ELISA in comparison to the reference antibodies Lecanemab (FIG.5A) and H2731 (FIG.5B). Antibodies were preincubated at 10ng / mL with dilutions of sAβ aggregates, Aβ1-40 monomer (mono), or Aβ1-28 monomer (mono). The remaining binding signal of the antibody was then measured by direct ELISA. More potent antibodies competed at lower concentrations of sAβ aggregates, such as antibodies 1G8, 3B8, 3E8, 4A10_M1, 4B2, 4D11, and H1G8_K1A3, and more selective antibodies had a wider range between sAβ aggregate and monomer curves, such as antibodies 1G8, 3B8, 3E8, 4A10_M1, 4D11, and H1G8_K1A3. In FIGs.5A-5I the vertical dotted lines at 133 picomolar Abeta concentration represented the presumed lower limit of detection at which point the number of Aβ peptides equals the number of antibody binding sites. Antibodies in the present invention showed a range of binding profiles, with many showing both strong potency to sAβ aggregates (greater than Lecanemab) and strong selectivity for sAβ aggregates over monomers (greater than H2731).

[0211] The binding kinetics of anti-Aβ antibodies to sAβ aggregates was measured by bio-Layer Interferometry (BLI) using Octet Red (Sartorius). Binding curves to sAβ aggregates from 40 nM to 0.625 nM (with 2-fold serial dilution) were determined for Lecanemab (FIG.6A), 1G8 (FIG.6B), 3E8 (FIG.6C), H1G8-K1A3 (FIG.6D), 4A10_M1 (FIG.6E), 4B2 (FIG.6F), 3B8 (FIG.6G), and H2731 (FIG.6H).

[0212] The apparent dissociation constants (KD) of the disclosed antibodies 1G8, 3E8, H1G8-K1A3, 4A10_M1, 4B2, 3B8, and H2731 ranged from 0.17 nM to 0.33 nM binding affinity for sAβ aggregates, compared to the reference antibody Lecanemab at 0.9 nM, and the monomer binding affinity of the disclosed antibodies ranged from 100 to 300 nM. The binding kinetics parameters were determined using Octet Analysis studio 12. The data was double referenced before the kinetic parameters were determined using 1: 1 binding model.Leydig 774215 73

[0213] These results demonstrate that binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein have superior binding affinity and selectivity towards aggregated forms of Aβ peptide compared to known Aβ peptide antibodies such as Lecanemab and H2731. The binding agents 1G8, 3B8, and 4B2 showed superior binding and / or selectivity characteristics compared to Lecanemab and H2731. This suggests that these binding agents targeted to an aggregated form of Aβ peptide may demonstrate increased potency and reduced off-target binding effects as a therapeutic for Alzheimer’s disease, or other diseases, disorders, or conditions responsive to binding of aggregated forms of Aβ peptide. EXAMPLE 3

[0214] This example demonstrates the binding of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein to Aβ plaques on unfixed, frozen brain sections from an AD mouse model (APP-SAA) and human donors with AD.

[0215] To investigate whether the antibodies described in this invention recognize disease associated Aβ plaques in the brain parenchyma, unfixed, frozen brain sections from human donors with pathological AD diagnosis (Braak stages IV – VI) or 7.5-month-old female APP- SAA mice were incubated with the selected antibodies in parallel with reference antibodies.

[0216] On brain sections of mouse model of AD (FIGs.7A and 7B), two reference antibodies, Lecanemab (FIG.7A, panel A) and H2731 (FIG.7A, panel B), as well as six selected antibodies described herein, 1G8 (FIG.7A, panel C), 3B8 (FIG.7A, panel D), 3E8 (FIG.7B, panel E), 4A10_M1 (FIG.7B, panel F), 4B2 (FIG.7B, panel G), and H1G5_K1A3 (FIG.7B, panel H), exhibit robust immunoreactivity to amyloid plaques. Three antibodies, in addition to two reference antibodies and one pan-anti-amyloid antibody control, were also tested on human AD brain sections (FIGs.8A and 8B). While all antibodies tested recognize human disease-associated Aβ plaques, Lecanemab (FIG.8A, panel A), 6E10 (FIG.8, panel F), and 4B2 (FIG.8B, panel E) have relatively weak immunoreactivity compared to H2731 (FIG.8A, panel B), which shows very strong binding against human Aβ plaques, and 1G8 (FIG.8A, panel C) and 3B8 (FIG.8A, panel D) which exhibit immunoreactivity stronger than Lecanemab, 6E10, and 4B2 but weaker than H2731.

[0217] These results demonstrate that the 1G8 and 3B8 binding agents described herein show superior immunoreactivity with aggregated forms of Aβ peptide compared to known Aβ peptide antibodies such as Lecanemab and H2731. This suggests that at least theseLeydig 774215 74 binding agents targeted to an aggregated form of Aβ peptide could be used at lower concentrations than known Aβ peptide antibodies such as Lecanemab and H2731, and therefore could be used as a more effective therapeutic for Alzheimer’s disease, or other diseases, disorders, or conditions responsive to binding of aggregated forms of Aβ peptide. EXAMPLE 4

[0218] This example demonstrates the ability of the binding agents targeted to the aggregated form of amyloid-beta (Aβ) peptide described herein to induce clearance of Aβ by stimulating phagocytosis of anti-Aβ antibodies.

[0219] To assess the ability of antibodies described in this invention to stimulate antibody-mediated phagocytosis, sAβ aggregates were pre-incubated with varying concentrations of the selected antibodies in parallel with reference antibodies prior to incubation with iPSC-derived microglia-like cells (iMGLs) in vitro. At all antibody concentrations tested, anti-sAβ antibodies increased phagocytosis of APC-labeled sAβ aggregates compared to hIgG isotype. This condition allows differentiation of phagocytic potencies of the tested antibodies. When normalized to the maximum mean fluorescence signal for a given antibody, antibodies 3E8, 4B2, 3B8, 1G8, 1A3, and 1B9 achieved about half maximal response at lower concentrations compared to the reference antibody Lecanemab indicating the higher potency of those antibodies in promoting phagocytosis of sAβ aggregates (FIG.9).

[0220] To evaluate the ability of antibodies described in this invention to promote phagocytosis of Aβ ex vivo, unfixed brain sections from 7.5-month-old female APP-SAA mice were pre-incubated with Lecanemab, H2731, IgG, H1G8-K1A3, 4A10_M1, 3B8, 3E8, 4B2, or 1G8 in parallel prior to incubation with iMGLs. Tissues were then incubated with anti-APP antibody 6E10 or Amylo-glo to visualize residual amyloid plaque. Phagocytic uptake was qualitatively assessed using immunofluorescent micrographs (FIG.10). Pre- treatment of brain sections with H2731, H1G8-K1A3, 3E8, 3B8, 4B2, and 1G8 antibodies reduced the mean plaque area by 25-75% compared to sections pre-treated with the hIgG isotype, while pre-treatment of brain sections with the reference antibody, Lecanemab, and 4A10_M1 did not reduce the mean plaque area.

[0221] These results demonstrate that at least the 3E8, 4B2, 3B8, 1G8, 1A3, and 1B9 binding agents described herein show superior potency in promoting phagocytosis of aggregated forms of Aβ peptide compared to known Aβ peptide antibodies such asLeydig 774215 75 Lecanemab and H2731 in both humans and mice. This suggests that at least these binding agents targeted to an aggregated form of Aβ peptide could be more effective at inducing clearance of pathogenic aggregated Aβ peptide antibodies than known Aβ peptide antibodies such as Lecanemab and H2731, and therefore could be used as a more effective therapeutic for Alzheimer’s disease, or other diseases, disorders, or conditions responsive to binding of aggregated forms of Aβ peptide. EXAMPLE 5

[0222] This example demonstrates the humanization and characterization of selected variants mouse anti-sAβ aggregate antibodies.

[0223] Three mouse anti-sAβ aggregate antibodies, 1G8, 3B8 and 4B2, were selected for humanization. The 16 humanized heavy chain variable and light chain variable sequences from mouse antibody 1G8 are shown in Table 7A, from mouse antibody 3B8 are shown in Table 7B, and from mouse antibody 4B2 are shown in Table 7C. CDRs as defined by IMGT notation are shown in bold with no underline. Additional residues that are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are underlined. Table 7A.1G8 Humanized variant sequences Binding SEQ Heavy SEQ Kappa Agent ID ID S H N T S H N TLeydig 774215 76 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO A L S F A L S F S H N T S H N T A L S F A L S FLeydig 774215 77 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO S H N T S H N T A L S F A L S F S H N T S H N TLeydig 774215 78 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO A L S F A L S F I F S P I F S P I W F SLeydig 774215 79 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO I W F S P I F S P I F S P I W F S I W F S P I F S PLeydig 774215 80 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO I F S P I W F S I W F S P I F S P I F S P I W F SLeydig 774215 81 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO I W F S PBinding SEQ Heavy SEQ Kappa T W R I V T W L I T W R I V T W L I VLeydig 774215 82 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO T W R I V T W L I T W R I V T W L I V T W R I VLeydig 774215 83 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO T W L I T W R I V T W L I V T W R I V T W L I T W R I VLeydig 774215 84 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO T W L I Vcloned into pcDNA3.1 vector with the human IgG1 constant sequence and human kappa constant sequence and humanized recombinant antibody variants were produced. The binding activity and binding kinetics of the humanized antibodies were measured by direct ELISA.

[0225] The binding activity of representative humanized variants as compared to the mouse (mu) parental antibodies was measured by direct ELISA for 1G8 (FIG.11A), 3B8 (FIG.11B), and 4B2 (FIG.11C). The EC50values for these antibodies are shown in Table 8. These data indicated that the binding activity of the humanized variants, when expressed, did not change significantly from the parental mouse antibodies. In Table 8, EC50refers to half maximal effective concentration and N.D. refers to not determined.Leydig 774215 85 Table 8. EC50Values for 1G8, 3B8, 4B2 mouse parental antibodies and humanized variants 1G8 EC50(µg / mL) 3B8 EC50(µg / mL) 4B2 EC50(µg / mL)1G8 mu 0.0028 3B8 mu 0.0129 4B2 mu 0.0046

[0226] These results demonstrate that the humanized variants of binding agents 1G8, 3B8, and 4B2 described herein show comparable or superior binding characteristics to aggregated forms of Aβ peptide compared to their parental mouse forms. This suggests that these humanized variants of binding agents 1G8, 3B8, and 4B2 could serve as effective therapeutics for Alzheimer’s disease, or other diseases, disorders, or conditions responsive to binding of aggregated forms of Aβ peptide, particularly in humans where they would be less likely to cause an immunogenic response. EXAMPLE 6

[0227] This example demonstrates the development of additional variants into the humanized framework of one of the binding agents described herein using lineage-based rational design (RD).

[0228] Variants were informed by identifying naturally-occurring CDR mutations discovered from mouse sequences within the related clonal expansion (or sites identified as likely important by these natural mutations and tested with different residues); theseLeydig 774215 86 mutations were then introduced into the humanized sequences in non-naturally-occurring combinations and then tested for Aβ binding characteristics.1G8_V3 was selected as the humanized sequence framework for the RD project. Mutations informed by related clones during initial discovery were then added, individually or in combination, to the 1G8_V3 backbone. Eleven (11) such sequences are shown in Table 9. CDRs as defined by IMGT notation are shown in bold with no underline. Additional residues that are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are underlined. The HCDRs and LCDRs of the RD sequence variants to 1G8_V3, along with underlined residues that are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are shown in Tables 10 and 11, respectively. Table 9. RD sequence variants to 1G8_V3 Binding SEQ Heavy SEQ Kappa Agent ID ID A T K A L D A T KLeydig 774215 87 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO A L S F A L D A L S F A T K A L S F A L S FLeydig 774215 88 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO A L V D A L S F. _ SEQ SEQ SEQ Binding Agent ID CDRH1 ID CDRH2 ID CDRH3Leydig 774215 89 Table 11. CDR sequences of the light chain variable regions of RD variants to 1G8_V3 SEQ SEQ SEQ Binding Agent ID CDRL1 ID CDRL2 ID CDRL3 T T T T T T T T T T T [ clo e o a a a e p ess o p as pc . u a g c seque ce and transfected into CHO cells for recombinant antibody production. The purified human recombinant antibodies were used to measure binding to sAβ aggregates or binding competition by Aβ monomers.

[0230] The binding activity of RD variants, as compared to the 1V3 parental antibodies, was measured by sAβ aggregate direct ELISA (FIG.12A and 12B), and competition ELISA (FIG.12C and 12D). The relative binding signal (inverse of EC50or IC50values) for these antibodies is shown in Table 12 where a value of 1.0 equals the signal of 1G8_V3, and higher numbers indicate more potent binding signal to the noted antigen compared to 1G8_V3. ND = no data or cannot be calculated. These data suggest that the binding activity of the RD variants was meaningfully altered relative to 1G8_V3. In some cases, selectivity is increased via more potent direct ELISA binding to sAβ aggregates and decreased competition by Aβ monomer.Leydig 774215 90 Table 12. Inverse EC50Values for RD sequence variants relative to 1G3_V3 (higher values correspond to stronger binding) sAβ aggregate direct ELISA Aβ monomercompetition ELISAto

[0231] This example demonstrates the development of additional variants into the humanized framework of one of the binding agents described herein using look-through- mutagenesis (LTM).

[0232] Variants were informed by conducting an alanine scan of 1G8_V3 and noting permissive residues. Those permissive residues were then mutated to a subset of amino acids via LTM and then tested for Aβ binding characteristics.1G8_V3 was selected for the LTM project. An alanine scan was conducted in which several mutants were produced, each with a mutation to alanine in one location of their CDRs. Residues of minimal impact on binding were considered likely not part of the paratope, and residues of total knockout were considered essential. Residues of intermediate impact were deemed “permissive” locations in which mutation may have the highest likelihood of modifying binding behavior relative to the parental while maintaining high potency. These permissive locations were mutated to a subset of amino acids across various chemical properties (for example, at each site, one residue was tested with a negative charge).10 such sequences are shown in Table 13. CDRs as defined by IMGT notation are shown in bold with no underline. Additional residues thatLeydig 774215 91 are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are underlined. The HCDRs and LCDRs of the RD sequence variants to 1G8_V3, along with underlined residues that are not included in the CDRs as defined by IMGT notation but may be involved in antigen binding based on in silico structural modeling and / or lineage mutation hotspot analysis are shown in Tables 14 and 15 respectively. Table 13. LTM sequence variants relative to 1G8_V3 Binding SEQ Heavy SEQ Kappa Agent ID ID I R I I W F S I W F S I W F SLeydig 774215 92 Binding SEQ Heavy SEQ Kappa Agent ID ID NO NO I W F S I W F S I F S I F S I F S I W F SLeydig 774215 93 Table 14. CDR sequences of the heavy chain variable regions of LTM variants of 1G8_V3 SEQ SEQ SEQ Binding Agent ID CDRH1 ID CDRH2 ID CDRH3 Y Y Y Y Y Y Y Y Y YTable 15. CDR sequences of the light chain variable regions of LTM variants of 1G8_V3 SEQ SEQ SEQ Binding Agent ID CDRL1 ID CDRL2 ID CDRL3 T T T T T T T T T T

[0233] The binding activity of LTM variants, as compared to the 1V3 parental antibodies, was measured by sAβ aggregate direct ELISA (FIGs.13A and 13B), and competition ELISA (FIGs.13C and 13D). The relative binding signal (inverse of EC50 or IC50 values) for these antibodies is shown in Table 16 where a value of 1.0 equals the signal of 1G8_V3, and higherLeydig 774215 94 numbers indicate more potent binding signal to the noted antigen compared to 1G8_V3. These data suggest that the binding activity of the LTM variants is meaningfully altered relative to 1G8_V3. In some cases, selectivity is increased via more potent direct ELISA binding to sAβ aggregates and decreased competition by Aβ monomer. Table 16. EC50 Values for LTM sequence variants relative to 1G3_V3 (higher values correspond to stronger binding) sAβ aggregate direct ELISA Aβ monomer competition ELISA Inv r EC r l tiv t 1G8 V3 Inv r IC r l tiv t 1G8 V3EXAMPLE 8

[0234] This example demonstrates the engineering of the binding agents described herein for modified avidity of binding to sAβ aggregates, relative to standard bivalent monoclonal antibodies, via the addition of two antigen-binding domains onto a standard IgG (bivalent) format, resulting in tetravalent constructs (referred here as multivalent, MV, clones).

[0235] It was observed that the high selectivity for sAβ aggregates over Aβ monomer of the binding agents described here is related, in part, to a relatively high impact of avidity where these binding agents maintain sustained binding preferentially when more than one binding domain is engaged with the antigen. sAβ aggregates are highly multimeric and Aβ monomers are not multimeric, therefore sAβ aggregates satisfy this avidity requirement. ByLeydig 774215 95 adding additional binding domains, it was hypothesized that the competition by monomer would remain unchanged but the sustained interaction with sAβ aggregates would increase

[0236] To generate an exemplary construct toward this end, binding agent 1B9 was used. 1B9 was expressed as chimeric human IgG1 with additional 1B9 scFvs fused to the C-termini of the light chains (also known as a “butterfly” format).1B9 multivalent is shown here as a non-limiting illustration, and any Aβ binding agent described herein, combinations of multiple Aβ binding agents described herein, or combinations of Aβ binding agents described herein fused with other Aβ binding agents may be substituted in multivalent (greater than two Aβ binding domains) format. The butterfly format with scFvs on the light chain C-termini is shown here as a non-limiting illustration of a higher-avidity binding agent, and any format allowing sustained binding due to addition of Aβ binding domains relative to standard bivalent IgG may be substituted, including constructs that are trivalent, tetravalent, pentavalent, hexavalent, septivalent, octavalent, or greater. The heavy chain and light chain variable and constant sequences for this exemplary 1B9 molecule are shown in Table 17.Leydig 774215 96 Table 17. LTM sequence variants relative to 1G8_V3 Binding SEQ Heavy SEQ Kappa Agent ID ID N N I G V K E P N S E I R S K F G G Q I N

[0237] The binding activity of 1B9_MV was compared with 1B9 parental (bivalent standard IgG). Monomer competition was measured by monomer competition ELISA as described above (FIG.14A), and sustained sAβ aggregate binding was measured by direct ELISA with 24 hour dissociation. Plates were coated with a standard protocol coating with sAβ aggregate, blocking, human Fc test antibody incubation, and wash. Samples then underwent a 24 hour dissociation step after test antibody binding in which plates were incubated with excess (10ug / mL) competing antibody with a mouse Fc. Finally, samples were developed with an anti-human Fc secondary. The goal of the dissociation step is to estimate the relative long-term dissociation of the multivalent constructs compared to standard IgG (FIG.14B). The IC50 and EC50 values of those tests are shown in Table 18. These data suggest that the monomer competition of the tetravalent MV clones is similar toLeydig 774215 97 the monomer competition in bivalent standard IgG clones, but the long-term sustained sAβ aggregate binding is greater in the MV molecule than the standard IgG molecule, consistent with the idea that addition of binding domains increases avidity and reduces dissociation from antigen. Table 18. EC50 Values for LTM sequence variants sAβ aggregate direct ELISAAβ monomer with 24h dissociation stepcompetition ELISA

[0238] This example illustrates the generation and evaluation of the anti-amyloid-beta (Aβ) binding agents described herein in a blood-brain barrier (BBB)-shuttled format for increased CNS delivery of the Aβ binding agent. The anti-amyloid binding agent chosen here for the point of illustration is 1G8_V3. The shuttle moiety selected for demonstration is a heavy chain only variable domain (VHH) that binds the transferrin receptor (TfR) and is known to the art. This specific BBB shuttle is used here solely as a non-limiting illustration of the concept; other BBB-shuttle moieties known in the art or discovered in the future may be substituted. The clone 1G8_V3 is also shown here as a non-limiting illustration, and any Aβ binding agents described herein may be substituted.

[0239] To generate this exemplary construct, 1G8_V3 was expressed with the monovalent VHH BBB shuttle using a “knob-in-hole” format Fc design with a linker (GGGSGGGS) (SEQ ID NO: 320) fused between the C-terminus of the “hole” Fc (SEQ ID NO: 321) and the VHH N-terminus. The “knob” heavy chain constant region (SEQ ID NO: 322) did not have any C-terminal additions. Heavy chain variable domain and light chain variable domain 1G8_V3 sequences were as described in SEQ ID NOs: 165 and 181, respectively. The light chain constant region was as described above (SEQ ID NO: 2). The resulting molecule with 1G8_V3 tagged with a monovalent VHH was named 1G8_V3_BBB. Constructs were expressed with three plasmids (heavy hole, heavy knob, kappa) and otherwise expressed as described above in CHO cells.Leydig 774215 98 Table 19. Knob-in-Hole Sequence SEQ Heavy Hole SEQ Heavy Knob ID ID N N C F T T R K V F Eo e o s a e o s u g, J u a oc - ce which the endogenous murine Tfrc extracellular domain (ECD) was replaced by human TFRC ECD (n = 4 per group) received a single 1.6 mg kg⁻¹ intravenous dose of either 1G8_V3 or 1G8_V3-BBB.24 hours post-dose, animals were perfused with PBS, and brain homogenates and plasma were analyzed by anti-human-Fc ELISA. The brain-to-plasma ratio of 1G8-V3-BBB was significantly higher than 1G8-V3 (p < 0.01, unpaired t-test) (FIG.15). The data confirm that appending a BBB-shuttle moiety to the anti-Aβ binding agents described here substantially increases CNS exposure. Because the shuttle domain is modular, analogous constructs may employ alternative BBB-shuttle entities (e.g., VHH, scFv, peptides, receptor ligands, VNARs, picobodies, aptamers, small-molecule conjugates, or other moiety allowing for BBB shuttling) and may be linked to any region of the anti-amyloid binding agent (N-terminus, C-terminus, Fc hinge, chemically through engineered cysteines or enzymatic tags, or via otherwise BBB modified variable or constant regions). Thus, these results demonstrate the concept of the anti-Aβ binding agents described here linked to a BBB-shuttle moiety for increased CNS delivery.Leydig 774215 99

[0241] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0242] The use of the terms “a” and “an” and “the” and “at least one” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0243] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

Leydig 774215 100 CLAIM(S):

1. A binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide and an immunoglobulin light chain variable region polypeptide, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22 and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23-42 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62 and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS, WAS, KVF, or any one of SEQ ID NOs: 83-102 and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122 and 275.

2. A binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123- 142, 163-178, 195-210, 227-242, 276-286, and 298-307 or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317 or at least the CDRs thereof.

3. A binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-142, 163-178, 195- 210, 227-242, 276-286, and 298-307 and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 143-162, 179-194, 211-226, 243-258, 287-297, and 308-317.

4. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 1, wherein:Leydig 774215 101 the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23- 42, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82, a complementarity determining region 2 (LCDR2) comprising any one of SEQ ID NOs: 83- 102, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122.

5. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 3-22, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 23- 42, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43-62; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 63-82, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS, WAS, KVF, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 103-122.

6. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 2, comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 123-142, or at least the complementarity determining regions (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 143-162, or at least the CDRs thereof.

7. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 3, comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 123-Leydig 774215 102 142, and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 143-162.

8. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 6, 16, and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 26 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43, 46, and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 66 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of SEQ ID NOs: 86, 88, and 273-274, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 106 and 275.

9. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 1, wherein: the immunoglobulin heavy chain variable region polypeptide comprises a complementarity determining region 1 (HCDR1) comprising any one of SEQ ID NOs: 6, 16, and 259, a complementarity determining region 2 (HCDR2) comprising any one of SEQ ID NOs: 26 and 260-261, and a complementarity determining region 3 (HCDR3) comprising any one of SEQ ID NOs: 43, 46, and 262-266; and the immunoglobulin light chain variable region polypeptide comprises a complementarity determining region 1 (LCDR1) comprising any one of SEQ ID NOs: 66 and 267-272, a complementarity determining region 2 (LCDR2) comprising any one of the amino acid sequences KVS and KVF, and a complementarity determining region 3 (LCDR3) comprising any one of SEQ ID NOs: 106 and 275.

10. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 2, comprising an immunoglobulin heavy chain variable region of any one of SEQ ID NOs: 276-286 and 298-307, or at least the complementarity determining regionsLeydig 774215 103 (CDRs) thereof; and an immunoglobulin light chain variable region of any one of SEQ ID NOs: 287-297 and 308-317, or at least the CDRs thereof.

11. The binding agent targeted to an aggregated form of amyloid-beta (Aβ) peptide of claim 3, comprising an immunoglobulin heavy chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 276- 286 and 298-307, and an immunoglobulin light chain variable region polypeptide with an amino acid sequence that is at least 90% identical to any one of SEQ ID NOs: 287-297 and 308-317.

12. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-3, which comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of SEQ ID NO: 83, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of SEQ ID NO: 84, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of SEQ ID NO: 85, and the LCDR3 of SEQ ID NO: 105; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of SEQ ID NO: 87, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 108;Leydig 774215 104 the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of SEQ ID NO: 89, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO: 110; the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of SEQ ID NO: 91, and the LCDR3 of SEQ ID NO: 111; the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of SEQ ID NO: 92, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of SEQ ID NO: 93, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of SEQ ID NO: 94, and the LCDR3 of SEQ ID NO: 114; the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of SEQ ID NO: 95, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of SEQ ID NO: 96, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO: 117;Leydig 774215 105 the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of SEQ ID NO: 98, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of SEQ ID NO: 99, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of SEQ ID NO: 100, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of SEQ ID NO: 101, and the LCDR3 of SEQ ID NO: 121; or the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of SEQ ID NO: 102, and the LCDR3 of SEQ ID NO:

122.

13. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-3, which comprises: the HCDR1 of SEQ ID NO: 3, the HCDR2 of SEQ ID NO: 23, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 63, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 103; the HCDR1 of SEQ ID NO: 4, the HCDR2 of SEQ ID NO: 24, the HCDR3 of SEQ ID NO: 44, the LCDR1 of SEQ ID NO: 64, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 104; the HCDR1 of SEQ ID NO: 5, the HCDR2 of SEQ ID NO: 25, the HCDR3 of SEQ ID NO: 45, the LCDR1 of SEQ ID NO: 65, the LCDR2 of SEQ ID NO: the amino acid sequence WAS, and the LCDR3 of SEQ ID NO: 105;Leydig 774215 106 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 7, the HCDR2 of SEQ ID NO: 27, the HCDR3 of SEQ ID NO: 47, the LCDR1 of SEQ ID NO: 67, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 107; the HCDR1 of SEQ ID NO: 8, the HCDR2 of SEQ ID NO: 28, the HCDR3 of SEQ ID NO: 48, the LCDR1 of SEQ ID NO: 68, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 108; the HCDR1 of SEQ ID NO: 9, the HCDR2 of SEQ ID NO: 29, the HCDR3 of SEQ ID NO: 49, the LCDR1 of SEQ ID NO: 69, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 109; the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of the amino acid sequence KVF, and the LCDR3 of SEQ ID NO: 110; the HCDR1 of SEQ ID NO: 11, the HCDR2 of SEQ ID NO: 31, the HCDR3 of SEQ ID NO: 51, the LCDR1 of SEQ ID NO: 71, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 111; the HCDR1 of SEQ ID NO: 12, the HCDR2 of SEQ ID NO: 32, the HCDR3 of SEQ ID NO: 52, the LCDR1 of SEQ ID NO: 72, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 112; the HCDR1 of SEQ ID NO: 13, the HCDR2 of SEQ ID NO: 33, the HCDR3 of SEQ ID NO: 53, the LCDR1 of SEQ ID NO: 73, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 113; the HCDR1 of SEQ ID NO: 14, the HCDR2 of SEQ ID NO: 34, the HCDR3 of SEQ ID NO: 54, the LCDR1 of SEQ ID NO: 74, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 114;Leydig 774215 107 the HCDR1 of SEQ ID NO: 15, the HCDR2 of SEQ ID NO: 35, the HCDR3 of SEQ ID NO: 55, the LCDR1 of SEQ ID NO: 75, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 115; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 36, the HCDR3 of SEQ ID NO: 56, the LCDR1 of SEQ ID NO: 76, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 116; the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 117; the HCDR1 of SEQ ID NO: 18, the HCDR2 of SEQ ID NO: 38, the HCDR3 of SEQ ID NO: 58, the LCDR1 of SEQ ID NO: 78, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 118; the HCDR1 of SEQ ID NO: 19, the HCDR2 of SEQ ID NO: 39, the HCDR3 of SEQ ID NO: 59, the LCDR1 of SEQ ID NO: 79, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 119; the HCDR1 of SEQ ID NO: 20, the HCDR2 of SEQ ID NO: 40, the HCDR3 of SEQ ID NO: 60, the LCDR1 of SEQ ID NO: 80, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 120; the HCDR1 of SEQ ID NO: 21, the HCDR2 of SEQ ID NO: 41, the HCDR3 of SEQ ID NO: 61, the LCDR1 of SEQ ID NO: 81, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 121; or the HCDR1 of SEQ ID NO: 22, the HCDR2 of SEQ ID NO: 42, the HCDR3 of SEQ ID NO: 62, the LCDR1 of SEQ ID NO: 82, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO:

122.

14. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-3, which comprises:Leydig 774215 108 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 273, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 88, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 109 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 274, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 110 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO: 106; or the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO:

275.

15. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-3, which comprises: the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of SEQ ID NO: the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: the amino acid sequence KVF, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 268, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 111 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 262, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 16, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 43, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 263, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 259, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 264, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 267, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 260, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 261, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106;Leydig 774215 112 the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 265, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 266, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 269, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO:270, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 271, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 272, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 106; or 16. the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of the amino acid sequence KVS, and the LCDR3 of SEQ ID NO: 275.The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-15, wherein the binding agent is an antibody or an antigen-binding fragment thereof.

17. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 16, wherein the binding agent is an antibody fragment selected from F(ab’)2, Fab’, Fab, Fv, scFv, dsFv, dAb, and a single chain binding polypeptide.

18. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 16, wherein the binding agent is an antibody.Leydig 774215 113 19. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 18, wherein the antibody is an IgG, IgM, IgA, IgD or IgE antibody.

20. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 18 or claim 19, wherein the antibody is an IgG antibody.

21. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 18-20, wherein the antibody is humanized.

22. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 20 or claim 21, comprising the HCDR1 of SEQ ID NO: 6, the HCDR2 of SEQ ID NO: 26, the HCDR3 of SEQ ID NO: 46, the LCDR1 of SEQ ID NO: 66, the LCDR2 of SEQ ID NO: 86, and the LCDR3 of SEQ ID NO:

106.

23. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 22, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 163 and 179, SEQ ID NOs: 164 and 180, SEQ ID NOs: 165 and 181, SEQ ID NOs: 166 and 182, SEQ ID NOs: 167 and 183, SEQ ID NOs: 168 and 184, SEQ ID NOs: 169 and 185, SEQ ID NOs: 170 and 186, SEQ ID NOs: 171 and 187, SEQ ID NOs: 172 and 188, SEQ ID NOs: 173 and 189, SEQ ID NOs: 174 and 190, SEQ ID NOs: 175 and 191, SEQ ID NOs: 176 and 192, SEQ ID NOs: 177 and 193, or SEQ ID NOs: 178 and 194.

24. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 20 or claim 21, comprising the HCDR1 of SEQ ID NO: 10, the HCDR2 of SEQ ID NO: 30, the HCDR3 of SEQ ID NO: 50, the LCDR1 of SEQ ID NO: 70, the LCDR2 of SEQ ID NO: 90, and the LCDR3 of SEQ ID NO:

110.

25. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 24, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 195 and 211, SEQ ID NOs: 196 and 212, SEQ ID NOs: 197 and 213, SEQ ID NOs: 198 and 214, SEQ ID NOs: 199 and 215, SEQ ID NOs: 200 and 216, SEQ ID NOs: 201 and 217, SEQ ID NOs: 202 and 218, SEQ ID NOs: 203 and 219, SEQ ID NOs: 204 and 220, SEQ ID NOs: 205 and 221, SEQ ID NOs: 206 and 222, SEQ ID NOs: 207 and 223, SEQ ID NOs: 208 and 224, SEQ ID NOs: 209 and 225, or SEQ ID NOs: 210 and 226.Leydig 774215 114 26. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 20 or claim 21, comprising the HCDR1 of SEQ ID NO: 17, the HCDR2 of SEQ ID NO: 37, the HCDR3 of SEQ ID NO: 57, the LCDR1 of SEQ ID NO: 77, the LCDR2 of SEQ ID NO: 97, and the LCDR3 of SEQ ID NO:

117.

27. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 26, which comprises the heavy and light chain immunoglobulin polypeptides of SEQ ID NOs: 227 and 243, SEQ ID NOs: 228 and 244, SEQ ID NOs: 229 and 245, SEQ ID NOs: 230 and 246, SEQ ID NOs: 231 and 247, SEQ ID NOs: 232 and 248, SEQ ID NOs: 233 and 249, SEQ ID NOs: 234 and 250, SEQ ID NOs: 235 and 251, SEQ ID NOs: 236 and 252, SEQ ID NOs: 237 and 253, SEQ ID NOs: 238 and 254, SEQ ID NOs: 239 and 255, SEQ ID NOs: 240 and 256, SEQ ID NOs: 241 and 257, or SEQ ID NOs: 242 and 258.

28. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-27, wherein the binding agent is, or is part of, a multispecific or bispecific antibody, chimeric antigen receptor, chimeric T cell receptor, bispecific T-cell engager, multivalent antibody, diabody, triabody, tetrabody, hexabody, bis-scFv fragment, Fab dimer, or Fab trimer.

29. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-28, comprising more than two binding domains per molecule, wherein the binding agent has a higher avidity of binding to sAβ aggregates as compared to the avidity of binding to sAβ aggregates of a binding agent having one or two binding domains per molecule.

30. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-29, wherein the binding agent is conjugated to a blood-brain barrier (BBB) shuttle moiety.

31. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 30, wherein the BBB shuttle moiety is a binding agent targeted to a transferrin receptor (TfR).Leydig 774215 115 32. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of claim 30 or claim 31, wherein the BBB shuttle moiety is an antibody or an antigen- binding fragment thereof.

33. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, wherein the binding agent is an antibody conjugate.

34. A nucleic acid encoding the heavy chain immunoglobulin polypeptide and the light chain immunoglobulin polypeptide of the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32.

35. A vector comprising the nucleic acid of claim 34.

36. An isolated cell comprising the nucleic acid of claim 34 or the vector of claim 35.

37. A method of providing the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, the method comprising expressing in a cell in vitro one or more nucleic acids encoding the immunoglobulin heavy and light chain polypeptides thereof.

38. A composition comprising the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, the nucleic acid of claim 34, or the vector of claim 35, and a pharmaceutically acceptable carrier.

39. The composition of claim 38 wherein the composition is formulated for nasal administration, intravenous injection, subcutaneous injection, or intraperitoneal injection.

40. The composition of claim 38 or claim 39, wherein the composition is formulated for intravenous injection.

41. The composition of claim 38 or claim 39, wherein the composition is formulated for subcutaneous injection.

42. The binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, or the composition of any one of claims 38-41, for use as aLeydig 774215 116 medicament for treating a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance.

43. The use of claim 42, wherein the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition.

44. The use of claim 43, wherein the neurodegenerative disease, disorder, or condition is Alzheimer’s disease.

45. The use of claim 43, wherein the neurodegenerative disease, disorder, or condition is Down’s syndrome.

46. The use of claim 42, wherein the disease, disorder, or condition is characterized by ocular deposition of aggregated Aβ.

47. The use of claim 42, wherein the disease, disorder, or condition is characterized by deposition of aggregated Aβ outside the central nervous system.

48. A method for treating or preventing a disease, disorder, or condition in a mammal that is responsive to aggregated form of amyloid-beta (Aβ) peptide binding or clearance, the method comprising administering the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, or the composition of any one of claims 38-41, to the mammal.

49. The method of claim 48, wherein the disease, disorder, or condition is a neurodegenerative disease, disorder, or condition.

50. The method of claim 49, wherein the neurodegenerative disease, disorder, or condition is Alzheimer’s disease.

51. The method of claim 49, wherein the neurodegenerative disease, disorder, or condition is Down’s syndrome.

52. The method of claim 48, wherein the disease, disorder, or condition is characterized by ocular deposition of aggregated Aβ.Leydig 774215 117 53. The method of claim 48, wherein the disease, disorder, or condition is characterized by deposition of aggregated Aβ outside the central nervous system.

54. The method of any one of claims 48-53, wherein the administration is via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection.

55. The method of any one of claims 48-54, wherein the administration is via intravenous injection.

56. The method of any one of claims 48-54, wherein the administration is via subcutaneous injection.

57. The method of any one of claims 48-56, wherein the mammal is a human.

58. A method for inducing clearance of an aggregated form of amyloid-beta (Aβ) peptide in a mammal, the method comprising administering the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, or the composition of any one of claims 38-41, to the mammal.

59. The method of claim 58, wherein the administration is via nasal delivery, intravenous injection, subcutaneous injection, or peritoneal injection.

60. The method of claim 58 or claim 59, wherein the administration is via intravenous injection.

61. The method of claim 58 or claim 59, wherein the administration is via subcutaneous injection.

62. The method of any one of claims 58-61, wherein the mammal is a human.

63. A hybridoma or cell line that expresses the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32.

64. A method of diagnosing Alzheimer’s disease in a mammal, the method comprising: (1) taking a biological sample of the mammal,Leydig 774215 118 (2) contacting the sample with the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, (3) measuring the concentration of complexes formed of the sample and the binding agent targeted to the aggregated form of amyloid-beta (Aβ) peptide of any one of claims 1-32, and comparing the concentration of complexes to a reference value.

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