Methods for removing pathogenic proteins

Abstract

The present invention provides a composition for treating diseases that are susceptible to the response by reducing the level of pathogenic proteins. [Solution] A pharmaceutical for the treatment of myasthenia gravis, comprising the following chemical formula: TIFF2026137111000081.tif88150 A pharmaceutical product is provided comprising a compound having or a pharmaceutically acceptable salt thereof.

Description

Technical Field

[0001] The present invention relates to the treatment of diseases mediated by pathogenic proteins. More specifically, the present invention relates to the treatment of diseases sensitive to response by reducing the level of pathogenic proteins using degraders, such as molecular degraders such as bifunctional molecular degraders.

Background Art

[0002] An increase in the level of circulating pathogenic proteins can be a contributing factor in the progression of various tumor diseases, immune-mediated diseases and other diseases. Although certain drugs are currently available in this field, there is a need for new drugs that can effectively treat the disease or slow down its progression.

Summary of the Invention

[0003] The present invention is directed to the treatment of diseases sensitive to response by reducing the level of pathogenic proteins in a subject that requires such treatment.

[0004] Subcutaneous delivery of bifunctional degraders has been found to be unexpectedly superior to their intravenous administration by providing a rapid and sustained reduction of pathogenic immunoglobulins. This observation has been found to be consistent across several classes and species of bifunctional degraders. We have found, quite surprisingly, that adsorption of degraders can occur first via diffusion into the lymphatic circulation, followed by delivery to the venous and ultimately systemic circulation. The present invention now makes it possible to enable early saturation of the degrader binding site by immunoglobulins. We have found that lymphatic flow from the subcutaneous injection site and antibody target can direct relatively undiluted degraders and degrader targets to a common anatomical confluence for mixing and high affinity before systemic dissemination. This directed target-mediated pharmacokinetic can efficiently facilitate the delivery of immunoglobulin-containing degraders to the hepatic ASGPR, thereby reducing the removal of "first-pass" drugs not bound by targets by the liver. Furthermore, the inventors have found that by regulating the molar excess of the degrading agent in the extravascular system (e.g., lymphatic vessels), a desired free molar excess of the degrading agent can be seeded into the venous circulation, thereby enabling intravascular binding of immunoglobulins.

[0005] In one embodiment, the present invention provides a composition or compound, such as a bifunctional degrading agent, for use in reducing the level of pathogenic protein in a subject. This use involves contacting the bifunctional degrading agent with a component of the extravascular system of the subject, wherein the bifunctional degrading agent has an affinity for (i) hepatocyte asialoglycoprotein (ASGPR) receptor expressed in the liver of the subject, and (ii) the pathogenic protein, in an amount effective in promoting a reduction in the level of pathogenic protein in the subject. In a related embodiment, the present invention provides a method for reducing the level of pathogenic protein in a subject by contacting the pathogenic protein with a bifunctional degrading agent in an amount effective in promoting a reduction in the level of pathogenic protein in the subject. This method may further include the step of assaying the subject to determine whether subcutaneous administration of the composition favorably reduces the level of pathogenic protein in the subject. The reduction in pathogenic protein levels in subjects after administration of a bifunctional degrading agent may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0006] In another embodiment, the present invention provides a composition (a bifunctional degrading agent) for use in treating a response-sensitive disease by reducing levels of pathogenic proteins. This use involves subcutaneously administering a therapeutically effective amount of the bifunctional degrading agent, which has affinity for (i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the subject, and (ii) pathogenic proteins, to a subject requiring such treatment. In a related embodiment, the present invention provides a method for treating a response-sensitive disease by reducing levels of pathogenic proteins by subcutaneously administering a therapeutically effective amount of the bifunctional degrading agent to a subject. This method may further include the step of assaying the subject to determine whether subcutaneous administration of the composition favorably treats the response-sensitive disease by reducing levels of pathogenic proteins. The reduction in pathogenic protein levels in the subject after administration of the bifunctional degrading agent to the subject may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0007] In yet another embodiment, the present invention provides a composition (a bifunctional degrading agent) for use in reducing the level of pathogenic proteins in a subject. This use involves administering a bifunctional degrading agent having affinity for (i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the subject, and (ii) pathogenic proteins, to the subject in an amount effective to promote a reduction in the level of pathogenic proteins in the subject, thereby achieving a pharmacodynamic / pharmacokinetic ratio (EC50) of at least 1.0–1.8 for monovalent degrading agents and 1.5–3.0 for bivalent degrading agents. In relevant embodiments, the present invention provides a method for reducing the level of pathogenic proteins in the subject by administering a bifunctional degrading agent to the subject in an amount effective to promote a reduction in the level of pathogenic proteins in the subject, thereby achieving a pharmacodynamic / pharmacokinetic ratio (EC50 / AUC). This method may further include the step of assaying the subject to determine whether subcutaneous administration of the composition favorably reduces the level of pathogenic proteins in the subject. For example, the pharmacodynamic / pharmacokinetic ratio (EC50 / AUC) of a monovalent degrading agent measured for IgG species at 7–14 days post-administration is at least 1. It may be 0 to 1.8, for example, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, or at least 1.8. For example, the measured pharmacodynamic / pharmacokinetic ratio (EC50 / AUC) of the divalent degrading agent for IgG species 7 to 14 days after administration may be at least 1.5 to 3.0, for example, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, at least 2.0, at least 2. 1, at least 2.2, at least 2.3, at least 2.4, at least 2.5, at least 2.6, at least 2.7, at least 2.8, at least 2.9, or at least 3.0. In one embodiment, the pathogenic protein may be a pathogenic IgG species. In another embodiment, the pathogenic protein may be a pathogenic IgA species such as Gd-IgA1. In another embodiment, the pathogenic protein may be a pathogenic IgD species. In another embodiment, the pathogenic protein may be a pathogenic IgE species.In another embodiment, the pathogenic protein may be a pathogenic IgM species. In one embodiment, a single SC dose of 500 mg of molecular degrader can achieve a sustained reduction of at least 60% of the pathogenic protein for 10 days.

[0008] In yet another embodiment, the present invention provides a composition (a bifunctional degrader) for use in the treatment of a disease in a subject. This use comprises administering to the subject in an amount effective to promote a reduction in the level of pathogenic protein in the subject, the bifunctional degrader having affinity for (i) hepatocyte ASGPR receptors expressed in the liver of the subject, and (ii) pathogenic protein, wherein the administration is carried out in a first step of (a) intravenously administering the bifunctional degrader, and (b) in a second step of administering the bifunctional degrader in a manner other than intravenous. In a related embodiment, the present invention provides a method for treating a disease in a subject, the method comprising administering to the subject in an amount effective to promote a reduction in the level of pathogenic protein in the subject, wherein the administration is carried out in a first step of (a) intravenously administering the bifunctional degrader, and (b) in a second step of administering the bifunctional degrader in a manner other than intravenous. This method may further include the step of assaying a subject to determine whether subcutaneous administration of the composition favorably treats the disease in the subject.

[0009] The present invention also provides subcutaneous use of a bifunctional protein degrader ("MODE(registered trademark)"). In one embodiment, the present invention provides treatment of a disease to which the response is sensitive by reducing the level of a pathogenic protein, the method comprising subcutaneously administering to a subject in need of such treatment a therapeutically effective amount of (i) hepatocyte asialoglycoprotein (ASGPR) receptor expressed in the liver of the subject, and (ii) a bifunctional degrader having affinity for the pathogenic protein. The reduction in the level of pathogenic protein in the subject after administration of the bifunctional degrader to the subject may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0010] In another embodiment, the bifunctional decomposition agent is administered by the subject or patient using an auto-injector.

[0011] In one embodiment, subcutaneous use of the MoDE® Degrader provides the use of a precision tool to rapidly, deeply, and selectively target the pathogenesis of the disease itself, rather than the patient's entire immune system, which can be comfortably administered in the patient's own home. MoDE degradation factors target a class of proteins involved in the pathogenesis of the disease.

[0012] Another embodiment of this method has a chemical formula selected from the Marcush group of bifunctional degrader chemical formulas (I), (II), and (III). [ka] [ka] [ka] In the formula, R2 is NHC(=O)CH3; R5 is CH2OH; the pathogenic protein targeting ligand is a ligand having affinity for the pathogenic protein; linker A is a chemical group that links the ASGPR ligand to linker B, linker C, or linker D; linker B is a chemical group that links linker A to the pathogenic protein targeting ligand; linker C is a chemical group that links linker C to the pathogenic protein targeting ligand; and linker D is a chemical group that links linker A to the pathogenic protein targeting ligand. In yet another embodiment, linkers A, B, C, and D are as defined in International Patent Publication WO 2021 / 155317.

[0013] In another embodiment of this use or method for treating the disease, a bifunctional degrader has the following general chemical structure: [ka] [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via the asiaroglycoprotein receptor or other receptor identified herein, preferably on the surface of hepatocytes and other degrading cells in or in a subject; [LINKER] is a chemical moiety having a valence of 1 to 15, which, if present, directly binds to [CPBM] or [CRBM] or binds [LINKER] to [CPBM] or [CRBM], where [LINKER] is covalently bonded to one or more [CRBM] and / or [CPBM] groups via a [CON] which optionally contains a [MULTICON] group, wherein [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself; k' is an integer from 1 to 15; j' is an integer from 1 to 15; h and h' are each independently integers from 0 to 15; iL is an integer from 0 to 15; however, at least one of h, h' and iL is at least 1. In yet another embodiment, [CPBM], [CON], [LINKER], and [CRBM] are as defined in International Patent Publication WO 2019 / 199634.

[0014] In another embodiment of this use or method for treating a disease, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin G ("IgG") degrading agent.

[0015] In yet another embodiment, the IgG degrading agent has the following structure, FCIII-GN3, as shown in Figure 15. [ka] Or a pharmaceutically acceptable salt thereof. FCIII-GN3 is a small molecule MoDE degrader under development for the treatment of IgG-mediated diseases such as Graves' disease. FCIII-GN3 is designed for self-administration via an easy-to-use and patient-friendly autoinjector.

[0016] In yet another embodiment, the IgG degrader has the following structure as shown in FIG. 16.

Chemical formula

[0017] In yet another embodiment, the IgG degrader has the following structure as shown in FIG. 17.

Chemical formula

[0018] In yet another embodiment, the IgG degrader has the following structure as shown in FIG. 18.

Chemical formula

[0019] The present invention also provides subcutaneous use of a bifunctional protein degrader ("TRAP®"). In one embodiment, the present invention provides treatment of a disease susceptible to the response by reducing levels of pathogenic proteins, the method comprising subcutaneously administering to a subject requiring such treatment a therapeutically effective amount of (i) hepatocyte asialoglycoprotein (ASGPR) receptor expressed in the liver of the subject, and (ii) a bifunctional degrader having affinity for pathogenic proteins. In another embodiment of the use or method for reducing levels of pathogenic proteins, the reduction in levels of pathogenic proteins in the subject is 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0020] In one embodiment, subcutaneous administration of a TRAP-degrading agent provides the use of a precision tool to rapidly, deeply, and selectively target the pathogenesis of the disease itself, rather than the patient's entire immune system, and which can be comfortably administered in the patient's own home. TRAP-degrading agents remove proteins that cause specific abnormal diseases, leaving healthy components of the immune system intact. For example, compound 1 is a precision tool that removes only the disease-causing entities, and then degrades IgA more deeply, rapidly, and potentially without the off-target effects of less precise treatment.

[0021] In another embodiment of this use or method for treating a disease, the bifunctional degrader of pathogenic proteins is a degrader of galactose-deficient immunoglobulin A ("Gd-IgA").

[0022] In yet another embodiment, the Gd-IgA degrader has the following structure, compound 1, as shown in Figure 19. [ka] or a pharmaceutically acceptable salt thereof.

[0023] In another embodiment of this use or method of treating the disease, the bifunctional degrader of pathogenic proteins is a degrader of anti-β1ECII autoantibodies. In yet another embodiment, the bifunctional degrader of anti-β1ECII autoantibodies has the following structure, compound 2, or a pharmaceutically acceptable salt thereof, as shown in Figure 20.

[0024] In another embodiment of this use or method for treating a disease, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin E ("IgE") degrading agent. In another embodiment, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin M ("IgM") degrading agent.

[0025] In one embodiment, the present invention provides a bifunctional degrader for use in reducing the level of pathogenic protein in a subject, the method comprising subcutaneously administering a therapeutically effective amount of the bifunctional degrader to the subject. This use or method may further include the step of assaying the subject to determine that the subcutaneous administration of the bifunctional degrader favorably treats a disease susceptible to the response by reducing the level of pathogenic protein, i.e., that the bifunctional degrader has been administered in a therapeutically effective amount. In another embodiment of the use or method for reducing the level of pathogenic protein, the reduction in the level of pathogenic protein in the subject is 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0026] In another embodiment of this use or method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is an IgG degrading agent. In yet another embodiment, the IgG degrading agent is FCIII-GN3 having the structure shown in Figure 15, or a pharmaceutically acceptable salt thereof.

[0027] In yet another embodiment, the IgG degrader has the structure shown in Figure 16, or a pharmaceutically acceptable salt thereof.

[0028] In yet another embodiment, the IgG degrader has the structure shown in Figure 17, or a pharmaceutically acceptable salt thereof.

[0029] In yet another embodiment, the IgG degrader has the structure shown in Figure 18, or a pharmaceutically acceptable salt thereof.

[0030] In another embodiment of this use or method for reducing the level of pathogenic protein, the bifunctional degrader of pathogenic protein is galactose-deficient immunoglobulin A ("Gd-IgA")

[0031] In yet another embodiment, the Gd-IgA degrader has the structure shown in Figure 19, or a pharmaceutically acceptable salt thereof.

[0032] In another embodiment of this use or method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is a degrading agent for anti-β1ECII autoantibodies.

[0033] In another embodiment of this use or method for reducing the level of pathogenic protein, the bifunctional degrading agent of the anti-β1ECII autoantibody has the structure shown in Figure 20, or a pharmaceutically acceptable salt thereof.

[0034] In another embodiment of this use or method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin E ("IgE") degrading agent. In another embodiment, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin M ("IgM") degrading agent.

[0035] The present invention provides an alternative subcutaneous use of a bifunctional protein degrader ("MODE(registered trademark)") for reducing levels of pathogenic proteins by contact with components of the extravascular system. In a related embodiment, the present invention comprises administering the bifunctional protein in an amount effective in promoting a reduction in levels of pathogenic proteins in an extravascular system component target. In another embodiment, the pathogenic protein mediates a disease selected from cancer, heart disease, autoimmune disease, or inflammatory disease. This use or method assays the target to determine whether this subcutaneous administration of the bifunctional protein degrader is effective in promoting a reduction in levels of pathogenic proteins in an extravascular system component target.

[0036] In another embodiment of the use or method for reducing the level of pathogenic protein, the pathogenic protein is an abnormal immunoglobulin. In yet another embodiment, the immunoglobulin is immunoglobulin A ("IgA"), immunoglobulin D ("IgD"), immunoglobulin E ("IgE"), immunoglobulin G ("IgG"), or immunoglobulin M ("IgM"). In yet another embodiment, the abnormal form of IgA is galactose-deficient immunoglobulin A1 "Gd-IgA".

[0037] In another embodiment of the use or method for reducing the level of pathogenic proteins, for example, the extravascular system is the lymphatic system. In yet another embodiment, the components of the lymphatic system are lymph, lymphatic vessels, lymph nodes, and lymphatic organs. In yet another embodiment, the lymphatic organs are the thymus, spleen, tonsils, bone marrow, or Peyer's patches.

[0038] Another embodiment of a use or method for reducing the level of pathogenic protein has at least one of the following: the bifunctional degrading agent has a chemical formula selected from the Markush group of chemical formulas (I), (II), and (III) as described above, where R2 is NHC(=O)CH3 and R5 is CH2OH; the pathogenic protein targeting ligand is a ligand having affinity for pathogenic protein; linker A is a chemical group that connects the ASGPR ligand to linker B, linker C, or linker D; linker B is a chemical group that links linker A and the pathogenic protein targeting ligand; linker C is a chemical group that links linker C and the pathogenic protein targeting ligand; and linker D is a chemical group that links linker A and the pathogenic protein targeting ligand. In yet another embodiment, linkers A, B, C, and D are as defined in International Publication No. 2021 / 155317.

[0039] In another embodiment of the use or method for reducing pathogenic protein levels, the bifunctional degrading agent has the following general chemical structure: [ka] As described in more detail above, in yet another embodiment, [CPBM], [CON], [LINKER], and [CRBM] are as defined in International Publication No. 2019 / 199634.

[0040] In another embodiment of the use or method for reducing pathogenic protein levels, for example, the bifunctional degrading agent is administered to the subject before contact with components of the extravascular system of the subject. In yet another embodiment, the administration is subcutaneous. In yet another embodiment, the administration is transdermal. In yet another embodiment, the administration is intramuscular.

[0041] In another embodiment of the use or method for reducing the level of pathogenic protein, the reduction in the level of pathogenic protein in the subject is 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0042] In another embodiment of the use or method for reducing the level of pathogenic protein, the reduction in the level of pathogenic protein lasts for at least 10 hours, at least 20 hours, at least 30 hours, at least 40 hours, at least 50 hours, at least 60 hours, at least 70 hours, at least 80 hours, at least 90 hours, or at least 100 hours after administration.

[0043] In another embodiment of the use or method for reducing pathogenic protein levels, the bifunctional degrading agent is an IgG degrading agent.

[0044] In yet another embodiment, the IgG degrading agent is FCIII-GN3 having the structure shown in Figure 15, or a pharmaceutically acceptable salt thereof.

[0045] In yet another embodiment, the IgG degrader has the structure shown in Figure 16, or a pharmaceutically acceptable salt thereof.

[0046] In yet another embodiment, the IgG degrader has the structure shown in Figure 17, or a pharmaceutically acceptable salt thereof.

[0047] In yet another embodiment, the IgG degrader has the structure shown in Figure 18, or a pharmaceutically acceptable salt thereof.

[0048] In another embodiment of a method for reducing pathogenic protein levels, the bifunctional degrading agent is a degrading agent for galactose-deficient immunoglobulin A ("Gd-IgA").

[0049] In yet another embodiment, the Gd-IgA degrader has the structure shown in Figure 19, or a pharmaceutically acceptable salt thereof.

[0050] In another embodiment of the method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is a degrading agent for anti-β1ECII autoantibodies.

[0051] In yet another embodiment, the bifunctional degrading agent for anti-β1ECII autoantibody has the structure shown in Figure 20, or a pharmaceutically acceptable salt thereof.

[0052] In another embodiment of the use or method for reducing the level of pathogenic proteins, the bifunctional degrading agent of the pathogenic proteins is an immunoglobulin E (IgE) degrading agent. In another embodiment, the bifunctional degrading agent of the pathogenic proteins is an immunoglobulin M (IgM) degrading agent.

[0053] This invention also reduces the level of pathogenic proteins and the specific pharmacodynamic / pharmacokinetic ratio. This use or method involves assaying a subject and subcutaneous administration of this bifunctional degrading agent to favorably reduce the level of pathogenic proteins and the specific pharmacodynamic / pharmacokinetic ratio.

[0054] In one embodiment, a method or use for reducing the level of pathogenic protein in a subject involves administering a bifunctional degrader having affinity for i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the subject, and ii) pathogenic protein, to the subject in an amount effective to promote the reduction of the level of pathogenic protein in the subject, thereby providing a pharmacodynamic / pharmacokinetic ratio (EC50 / AUC) measured 7–14 days after administration, at least 1.0–1.8 for monovalent degraders and 1.5–3.0 for bivalent degraders.

[0055] In another embodiment of the use or method, or administration to reduce the level of pathogenic protein, is subcutaneous. In another embodiment, administration is transdermal. In yet another embodiment, administration is intramuscular.

[0056] In another embodiment of the use or method, the bifunctional degrading agent for reducing the level of pathogenic protein has a chemical formula selected from the Markush group of chemical formulas (I), (II), and (III) as described above, where R2 is NHC(=O)CH3 and R5 is CH2OH; the pathogenic protein targeting ligand is a ligand having affinity for pathogenic protein; linker A is a chemical group that connects the ASGPR ligand to linker B, linker C or linker D; linker B is a chemical group that links linker A and the pathogenic protein targeting ligand; linker C is a chemical group that links linker C and the pathogenic protein targeting ligand; and linker D is a chemical group that links linker A and the pathogenic protein targeting ligand. In yet another embodiment, linker A, linker B, linker C and linker D are as defined in International Publication No. 2021 / 155317.

[0057] In another embodiment of the use or method for reducing the level of pathogenic proteins, the bifunctional degrading agent has the following general chemical structure: [ka] As described in more detail above, in yet another embodiment, [CPBM], [CON], [LINKER], and [CRBM] are as defined in International Publication No. 2019 / 199634.

[0058] In another embodiment of the method for reducing the level of pathogenic protein, the bifunctional degrading agent is an IgG degrading agent.

[0059] In yet another embodiment, the IgG degrading agent is FCIII-GN3 having the structure shown in Figure 15, or a pharmaceutically acceptable salt thereof.

[0060] In yet another embodiment, the IgG degrader has the structure shown in Figure 16, or a pharmaceutically acceptable salt thereof.

[0061] In yet another embodiment, the IgG degrader has the structure shown in Figure 17, or a pharmaceutically acceptable salt thereof.

[0062] In yet another embodiment, the IgG degrader has the structure shown in Figure 18, or a pharmaceutically acceptable salt thereof.

[0063] In another embodiment of the method for reducing the level of pathogenic protein, the bifunctional degrader is a degrader for galactose-deficient immunoglobulin A ("Gd-IgA").

[0064] In yet another embodiment, the Gd-IgA degrader has the structure shown in Figure 19, or a pharmaceutically acceptable salt thereof.

[0065] In another embodiment of the method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is a degrading agent for anti-β1ECII autoantibodies.

[0066] In yet another embodiment, the bifunctional degrading agent for anti-β1ECII autoantibody has the structure shown in Figure 20, or a pharmaceutically acceptable salt thereof.

[0067] In another embodiment of the method for reducing the level of pathogenic proteins, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin E ("IgE") degrading agent. In another embodiment, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin M ("IgM") degrading agent.

[0068] The present invention provides a method for reducing the level of pathogenic proteins by administering a bifunctional degrader using different modalities. This use or method may further include the step of assaying the subject to determine whether this subcutaneous administration of the bifunctional degrader favorably reduces the level of pathogenic proteins by modality.

[0069] In one embodiment, the use or method of disease in a subject involves administering to the subject a bifunctional degrader having affinity for (i) hepatocyte ASGPR receptors expressed in the liver of the subject, and (ii) a pathogenic protein, in an amount effective to promote a reduction in the level of pathogenic protein in the subject. The administration is carried out in a first step of a) the degrader being administered intravenously, and b) the degrader being administered by a method other than intravenous administration.

[0070] In another embodiment of the use or method for treating a disease, the pathogenic protein mediates a disease selected from cancer, heart disease, autoimmune disease, or inflammatory disease. This use or method may further include the step of assaying the subject to determine that this subcutaneous administration of the bifunctional degrading agent favorably reduces the level of a particular pathogenic protein.

[0071] In another embodiment of the use or method for treating a disease, the pathogenic protein is an abnormal immunoglobulin.

[0072] In yet another embodiment, the immunoglobulin is immunoglobulin A ("IgA"), immunoglobulin D ("IgD"), immunoglobulin E ("IgE"), immunoglobulin G ("IgG"), or immunoglobulin M ("IgM"). In yet another embodiment, the abnormal form of IgA is galactose-deficient immunoglobulin A ("Gd-IgA").

[0073] In another embodiment of the use or method of the present invention, or in the step of treating a disease, the bifunctional degrader is administered subcutaneously in the second step. In another embodiment of the method of the present invention, when treating a disease, the degrader is administered transdermally in the second step. In another embodiment, in the second step, the degrader is administered intramuscularly.

[0074] In another embodiment of the use or method of or for treating a disease, the bifunctional degrading agent has a chemical formula selected from the Markush group of chemical formulas (I), (II), and (III) as described above, where R2 is NHC(=O)CH3; R5 is CH2OH; the pathogenic protein targeting ligand is a ligand having affinity for a pathogenic protein; linker A is a chemical group that connects the ASGPR ligand to linker B, linker C, or linker D; linker B is a chemical group that links the linkers and the pathogenic protein targeting ligand; linker C is a chemical group that links the linkers and the pathogenic protein targeting ligand; and linker D is a chemical group that links the linkers and the pathogenic protein targeting ligand. In yet another embodiment, linker A, linker B, linker C, and linker D are as defined in International Publication No. 2021 / 155317.

[0075] In another embodiment of a method for treating a disease, the bifunctional decomposition agent has the following general chemical structure: [ka] As described in more detail above, in yet another embodiment, [CPBM], [CON], [LINKER], and [CRBM] are as defined in International Publication No. 2019 / 199634.

[0076] In another embodiment of the method for treating the disease, the bifunctional degrading agent is an IgG degrading agent.

[0077] In yet another embodiment, the IgG degrading agent is FCIII-GN3 having the structure shown in Figure 15, or a pharmaceutically acceptable salt thereof.

[0078] In yet another embodiment, the IgG degrader has the structure shown in Figure 16, or a pharmaceutically acceptable salt thereof.

[0079] In yet another embodiment, the IgG degrader has the structure shown in Figure 17, or a pharmaceutically acceptable salt thereof.

[0080] In yet another embodiment, the IgG degrader has the structure shown in Figure 18, or a pharmaceutically acceptable salt thereof.

[0081] In another embodiment of a method for treating the disease, the bifunctional degrader is a degrader for galactose-deficient immunoglobulin A ("Gd-IgA").

[0082] In yet another embodiment, the Gd-IgA degrader has the structure shown in Figure 19, or a pharmaceutically acceptable salt thereof.

[0083] In another embodiment of a use or method for treating a disease, the bifunctional degrading agent for pathogenic proteins is a degrading agent for anti-β1ECII autoantibodies.

[0084] In yet another embodiment, the bifunctional degrading agent for anti-β1ECII autoantibody has the structure shown in Figure 20, or a pharmaceutically acceptable salt thereof.

[0085] In another embodiment of a use or method for treating a disease, the bifunctional degrading agent for pathogenic proteins is an immunoglobulin E ("IgE") degrading agent. In another embodiment, the degrading agent for pathogenic proteins is an immunoglobulin M ("IgM") degrading agent.

[0086] One embodiment provides a method for treating a disease to which the response is sensitive by reducing IgG levels, the method comprising subcutaneously administering a therapeutically effective amount of a pathogenic protein degrader to a subject in need of such treatment.

[0087] In another embodiment, a method is provided for reducing the level of IgG in a subject, comprising subcutaneously administering a therapeutically effective amount of a pathogenic protein degrader to the subject.

[0088] Some of the objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of embodiments of the invention, along with the accompanying drawings. [Brief explanation of the drawing]

[0089] For illustrative purposes, several embodiments of the present invention are shown in the drawings described below. Similar figures in the drawings indicate similar elements throughout. The present invention is not limited to the exact arrangements, dimensions, and fixtures shown.

[0090] [Figure 1] Figure 1 is a line graph showing pharmacodynamic data from FCIII-GN3 treated subjects. The Y-axis shows the total of subclasses IgG1, IgG2, and IgG4 as a percentage of baseline (before administration). The X-axis shows days 0 to 36 on a fixed time scale. The data is shown in the table below.

[0091] [Figure 2] Figure 2 is a line graph showing pharmacodynamic data from subjects treated with FCIII-GN3. The Y-axis represents the total IgG percentage at baseline (before administration). The X-axis represents days 0 to 36 on a fixed time scale. The data is shown in the table below.

[0092] [Figure 3] Figure 3 is a table showing the results of subcutaneous administration of FCIII-GN3.

[0093] [Figure 4] Figure 4 is a table showing the results of subcutaneous administration of FCIII-GN3.

[0094] [Figure 5] Figure 5 is a line graph showing the results of subcutaneous administration of 500 mg of FCIII-GN3. The Y-axis represents the baseline (before administration) total IgG percentage.

[0095] [Figure 6]Figure 6 is a line graph showing pharmacodynamic data from FCIII-GN3 treated subjects. The Y-axis represents the total IgG percentage at baseline (before administration). The X-axis represents the first 15 days on a continuous scale. The time points represent the mean for treatments with five or more observations.

[0096] [Figure 7] Figure 7 is a line graph showing pharmacodynamic data from FCIII-GN3 treated subjects. The Y-axis shows the total of subclasses IgG1, IgG2, and IgG4 as a percentage of baseline (before administration). The X-axis shows days 0 to 36 on a fixed time scale. The data is shown in the table below.

[0097] [Figure 8] Figure 8 is a line graph showing the results of FCIII-GN3 administration, displaying concentration-time curves after intravenous and subcutaneous administration of 500 mg. These results demonstrate a dose-dependent, rapid decrease in IgG with favorable safety and a profile suitable for subcutaneous administration.

[0098] [Figure 9] Figure 9 is a line graph showing the results of weekly administration of 2000 mg of FCIII-GN3. Baseline is the mean of pre-administration values ​​on day -1 and day 1. For weeks 1 through 4, the black circles represent the median maximum total IgG% change from baseline for that week. The bars indicate the 25th and 75th percentiles. See Example 1 for further details.

[0099] [Figure 10] Figure 10 is a line graph showing the results of administering 1000 mg and 2000 mg of FCIII-GN3. Baseline is the mean before administration on day -1 and day 1. Black circles represent the median of the maximum total IgG% change from baseline on each day. Bars indicate the 25th and 75th percentiles. See Example 1 for further details.

[0100] [Figure 11] Figure 11 is a line graph showing the results of administering FCIII-GN3 at 1000 mg and 2000 mg doses. The graph shows a rapid and deeper decrease in IgG, outperforming VYVAGART Hytrulo® by week 3. Baseline is the mean pre-administration values ​​for day -1 and day 1. From week 1 to week 4, the black circles represent the median maximum total Ig% change from baseline for that week, and the bars represent the 25th and 75th percentiles. See Example 1 for further details.

[0101] [Figure 12] Figure 12 is a line graph showing the results of the administration. Baseline is the mean of pre-administration values ​​on day -1 and day 1. The median of the maximum total IgG% change from baseline for that week. The bars represent the 25th and 75th percentiles. See Example 1 for details.

[0102] [Figure 13] Figure 13 is a line graph showing that a single subcutaneous administration of compound 1 results in rapid, selective, deep, and sustained removal of Gd-IgA1.

[0103] [Figure 14] Figure 14 is a line graph showing the results of a single 500 mg subcutaneous administration of compound 1. Baseline is pre-administration on day 1. Black circles represent the median 1% change in Gd-IgA from baseline for each day. Bars represent the 25th and 75th percentiles.

[0104] [Figure 15] Figure 15 shows the chemical structure of FCIII-GN3. FCIII-GN3 has a beta-anomeric carbon stereochemistry.

[0105] [Figure 16] Figure 16 shows the chemical structure of compound 4. Compound 4 has alpha-anomeric carbon stereochemistry.

[0106] [Figure 17] Figure 17 shows the chemical structure of another IgG degrading agent.

[0107] [Figure 18] Figure 18 shows the chemical structure of another IgG degrading agent.

[0108] [Figure 19] Figure 19 shows the structure of compound 1. Compound 1 has a beta-anomeric carbon stereochemistry.

[0109] [Figure 20] Figure 20 shows the chemical structure of compound 2.

[0110] [Figure 21] Figure 21 is a line graph showing the mean plasma concentration profiles of compound 4 on days 1 and 10 in male cynomolgus monkeys after twice-weekly subcutaneous administration of compound 4 at 3 mg / kg, 10 mg / kg, and 30 mg / kg over a two-week period. Individual and mean plasma concentrations of compound 4 are shown.

[0111] [Figure 22] Figure 22 is a line graph showing that subcutaneous administration of compound 1 (single 500 mg dose) results in rapid, selective, deep, and sustained removal of Gd-IgA1. Black circles represent the mean 1% change in Gd-IgA from baseline each day, and bars represent the standard error.

[0112] [Figure 23] Figure 23 is a line graph showing that intravenous and subcutaneous injection of compound 3 (0.77 mg / kg) reduces circulating IgG4 bolus (2 mg / kg intravenously) in nude mice. Mice administered compound 3 intravenously or subcutaneously 15 minutes after hIgG4 showed significant hIgG4 depletion compared to control mice receiving hIgG4 alone.

[0113] [Figure 24]Figure 24 is a bar graph showing that intravenous bolus and subcutaneous injection of compound 3 reduce circulating IgG4 in nude mice. Further quantification of the reduction in hIgG4 as the area under the curve indicates that intravenous and subcutaneous administration of compound 3 depleted 71% and 87.3% of hIgG4, respectively, compared to the control group. This graph demonstrates potent IgG4 depletion and high subcutaneous bioavailability.

[0114] [Figure 25] Figure 25 is a line graph showing the pharmacokinetics of compound 3 administered intravenously or subcutaneously (0.77 mg / kg), as detected in plasma up to 2 hours after injection.

[0115] [Figure 26] Figure 26 is a line graph showing the pharmacokinetics of compound 3 after subcutaneous administration versus intravenous administration (0.77 mg / kg). Subcutaneous bioavailability was calculated using the formula: F = AUC subcutaneous (2 hours) / AUC intravenous (2 hours), with F = 71%.

[0116] [Figure 27] Figure 27 is a series of scatter plots showing the detection of pancreatic islet autoantibodies in human plasma samples.

[0117] [Figure 28] Figure 28 is a line graph showing TRAP 2-mediated intracellular internalization and degradation of proinsulin antibodies. ASGPR-expressing HEK293 cells were incubated for 18 hours with dose curves of TRAP 2 and 50 nM fluorescently labeled monoclonal antibodies targeting different proinsulin epitopes. Dose-dependent internalization of the fluorescent antibody was captured using live-cell imaging.

[0118] [Figure 29]Figure 29 is a bar graph showing TRAP 2-mediated intracellular internalization and degradation of proinsulin antibody. ASGPR-expressing HEK293 cells were incubated with 100 nM monoclonal anti-proinsulin antibody and TRAP 2 (number 3 ± 200 nM) for 3 hours to promote ASGPR-mediated internalization. After internalization, cells were washed with excess antibody and drug and then incubated with fresh medium for up to 24 hours. Lysates were collected throughout the 24-hour period and analyzed by Western blotting with fluorescent anti-human IgG to demonstrate lysosomal degradation of anti-proinsulin.

[0119] [Figure 30] Figure 30 is a line graph showing blood glucose levels in TRAP 1 versus TRAP 2.

[0120] [Figure 31] Figure 31 shows the bioavailability, antibody binding, and antibody clearance of TRAP. In pharmacokinetic assays, NOD mice were injected with 3 mpk of TRAP 2 subcutaneously or intravenously. Nude mice were injected with human insulin antibody conjugated with Alexa Fluor 594 and vehicle (left) or TRAP 2 (right). Liver was removed 30 minutes after injection. The presence of anti-insulin antibodies (red) was observed on hepatic sinusoidal capillaries. NOD mice were screened for insulin autoantibodies and for the presence of proinsulin autoantibodies using MSD assay pharmacodynamic analysis.

[0121] [Figure 32] Figure 32 shows the in pharmacodynamic analysis, in which selected mice were injected subcutaneously with 3 mpk or 8 mpk of TRAP 2.

[0122] [Figure 33] Figure 33 shows the binding of TRAP 1 and TRAP 2 to autoantibodies derived from patients with type 1 diabetes. [Modes for carrying out the invention]

[0123] Detailed description of the invention The following detailed description is provided to assist those skilled in the biomedical field in carrying out the invention. Embodiments of the invention are described in detail below. However, these embodiments are illustrative only, and this disclosure is not limited thereto, but is defined rather by the appended claims. Those skilled in the biomedical field can modify and alter the embodiments described herein without departing from the spirit or scope of this disclosure.

[0124] Therefore, embodiments are simply described below by reference to structures and methods in order to illustrate the aspects of the description. Industrial applicability

[0125] Subcutaneous administration of the IgG degrading agent FCIII-GN3 consistently demonstrated a rapid, deep, and sustained reduction in total IgG. Clinical data show that FCIII-GN3 administered at 2000 mg weekly achieved a rapid, deep, and sustained reduction in total IgG, with a decrease of up to 85% within 16 days of a single dose.

[0126] The range of IgG reduction possible by varying the FCIII-GN3 dose allows for adjustable dosing regimens for acute and chronic disease management, with higher dose levels planned for acute disease management and lower, less frequent dosing planned for chronic disease management.

[0127] Subcutaneous administration of the Gd-IgA1 degrading agent compound 1 achieved rapid, deep, selective, and sustained reduction of Gd-IgA1, distinguishing this TRAP degrading agent from complement and BlyS / APRIL inhibitor competition. A reduction of up to 81% of Gd-IgA1 was observed, and the reduction from baseline persisted for several weeks after a single subcutaneous dose. Compound 1 is rationally designed to selectively remove galactose-deficient IgA1 (Gd-IgA1), the pathogenic antibody driver of the disease, while preserving healthy antibodies IgG, IgA, IgD, IgE, and IgM, thus providing a precise immunology to the therapeutic prospects of IgAN. Preservation of immunoglobulins, the complement system, and cell-mediated and humoral immunity provides a key distinction from immunosuppressive BlyS / APRIL inhibitors, complement inhibitors, and budesonides. definition

[0128] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the biomedical field. Terms used in the description are for illustrative purposes only and are not intended to limit the embodiments. Terms as defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meanings in the context of the relevant art and this disclosure, and not as idealized or overly formal unless expressly defined herein.

[0129] As used herein, unless otherwise expressly provided herein, each of the following terms shall have the meanings set forth below. Further definitions are provided throughout this application. If a term is not specifically defined herein, it shall be given the meaning known in the art to those skilled in the art who apply the term in connection with its use in describing the invention.

[0130] The terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and sections, but these elements, components, regions, layers, and sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Accordingly, a first element, component, region, layer, or section described below may be referred to as a second element, component, region, layer, or section without departing from the teaching of the embodiments.

[0131] The articles "a" and "an" refer to one or more, i.e., at least one of the grammatical objects of the article, unless the context clearly indicates otherwise. For example, "an element" means one or more elements.

[0132] As used herein, the term "ABT" means the binding portion in the composition (drug) of interest, which is an antibody, antibody variant, or antigen-binding fragment thereof that binds to the sFLT1 of interest in the subject or patient.

[0133] The term "active ingredient" has the meaning, as defined by the U.S. Food and Drug Administration, of any component that provides pharmacological activity or other direct effect in the diagnosis, cure, alleviation, treatment, or prevention of a disease, or that affects the structure or any function of the human or animal body.

[0134] The term “adverse event” (AE) has the meaning of any adverse medical occurrence in a human being related to the use of a drug product, whether or not it is considered to be related to the drug product, as provided by the U.S. Food and Drug Administration. Adverse events may occur during the use of a formulation; from an overdose of the formulation, whether accidental or intentional; from abuse of the formulation; or from discontinuation of the formulation (e.g., physiological discontinuation), and include any failure of the expected pharmacological effect. 21 CFR §251.2. Adverse events may be coded using the current edition of the Regulatory Activity Medical Dictionary.

[0135] The term "pharmaceutical" has the meaning recognized in the biomedical field as a composition of substances useful for performing a function. Several biomedically useful functions are described herein.

[0136] The term "alleviate" has the meaning of a process that reduces the severity of a sign or symptom of a disorder, as recognized in the biomedical field. A sign or symptom may be alleviated without being eliminated. Administration of the composition or pharmaceutical composition of the present invention may result in the elimination of a sign or symptom; however, elimination is not required. An effective dose should be expected to reduce the severity of the sign or symptom.

[0137] The term "analog" has a recognized meaning in the biomedical field for molecules that are not identical but possess similar functional or structural characteristics. Biochemical modifications can increase the protease resistance, membrane permeability, or half-life of an analog without altering ligand binding. Insulin analogs are well known in the biomedical field, such as rapid-acting insulin.

[0138] The term "and / or" includes any and all combinations of one or more of the related enumerated items. The term "or" means "and / or". Expressions such as "at least one" qualify the entire list of elements when they precede a list of elements, not the individual elements of the list.

[0139] The term "anti-drug antibody (ADA)" has a recognized meaning in the biomedical field. Many anti-drug antibodies are IgG4 antibodies, such as those used in factor VIII hemophilia.

[0140] The term "anti-galactose-deficient IgA1 (Gd-IgA1) antibody" has a recognized meaning in the biomedical field of an antibody that selectively binds to galactose-deficient IgA1. In some embodiments of the present invention, the anti-galactose-deficient IgA1 antibody is a published Km55 antibody, a Km55 variant, or its antigen-binding fragment.

[0141] The term "anti-insulin antibody" has a recognized meaning in the biomedical field and includes insulin autoantibodies (IAAs). Anti-C-peptide antibodies are commercially available. See also recombinant mouse anti-C-peptide antibody (CB2931), product number CBMAB-MD1611-LY, available from Creative Biolabs, Shirley, NY, USA. See also recombinant mouse anti-C-peptide antibody (CBFYR0644), product number CBMAB-MD 0644-FY, available from Creative Biolabs, Shirley, NY, USA. Human (chimeric) anti-insulin recombinant antibody (clone mAb49), available from Creative Biolabs, product number FAMAB-0225WJ. The inventors have found that synthetic insulin MoDE has similar affinity to mAb49.

[0142] The term “antigen-binding fragment” has the following meanings as recognized in the biomedical field: (1) an intact antibody fragment that binds to the same antigen recognized by a full-length antibody, e.g., F(ab')2, F(ab)2; (2) any synthetic or genetically engineered protein that acts like an antibody by binding to a specific antigen and forming a complex. The term antigen-binding portion of an antibody encompasses single-chain antibodies.

[0143] The term "asialoclycoprotein receptor (ASGPR)" has a recognized meaning in the biomedical field as a lectin that binds to asialoclycoproteins and glycoproteins in which sialic acid has been removed, exposing galactose residues. These cellular receptors are located on mammalian hepatocytes and other cells, such as glandular cells of the gallbladder and stomach. ASGPRs remove glycoproteins from circulation.

[0144] The phrase "at least one" qualifies the entire list of elements when it precedes a list of elements, but not the individual elements of the list.

[0145] As used herein, the term "AT" means a portion of a composition (pharmaceutical) that binds to the target sFLT1 in a subject or patient.

[0146] The term “autoimmune disease” is used herein to refer to a disease or illness that occurs when body tissues are attacked by their own immune system. The immune system is a complex system of tissues in the body that is typically designed to “search for and destroy” invaders of the body, including infectious agents. In diseases described as autoimmune diseases, MIF levels are often elevated. Embodiments of the present invention aim to improve many of the symptoms and secondary effects of these disease conditions and conditions by inhibiting or reducing elevated M1F levels and decreasing MIF levels in patients with autoimmune diseases (as well as inflammatory diseases and conditions and cancers). Examples of autoimmune diseases that often show high levels of MIF expression include, for example, systemic lupus erythematosus, Sjögren's syndrome, Hashimoto's thyroiditis, rheumatoid arthritis, juvenile (type 1) diabetes mellitus, polymyositis, scleroderma, Addison's disease, vitiligo, pernicious anemia, glomerulonephritis, and pulmonary fibrosis.

[0147] The term "binding portion" has a recognized meaning in the biomedical field as referring to a portion of a binding protein that binds to sFLT1, such as an antibody, antibody variant, or its antigen-binding fragment.

[0148] The term "cancer" is used throughout this specification to refer to the pathological process resulting in the formation and growth of malignant neoplasms, i.e., abnormal tissues that grow, often more rapidly than normal, by cell proliferation and continue to grow after the stimulus that initiated the new growth has ceased. Malignant neoplasms exhibit a partial or complete lack of structural organization and functional coordination with normal tissue, most invade surrounding tissues, metastasize to several sites, recur after attempted removal, and are likely to cause death to the patient unless properly treated. Neoplasms include, but are not limited to, morphological irregularities of cells in the tissue of the subject or host, as well as pathological proliferation of cells in the tissue of the subject compared to normal proliferation in the same type of tissue. Neoplasms include benign and malignant tumors (e.g., colon tumors), which can be either invasive or non-invasive. Malignant neoplasms (cancer) are distinguished from benign neoplasms in that the former exhibit a greater degree of anaplasia, or loss of cell differentiation and orientation, and have invasive and metastatic characteristics. Examples of neoplasms or cancers from which the target cells of the present invention may originate include, but are not limited to, carcinomas (e.g., squamous cell carcinoma, adenocarcinoma, hepatocellular carcinoma, and renal cell carcinoma), particularly bladder cancer, intestinal cancer, breast cancer, cervical cancer, colon cancer, esophageal cancer, head cancer, kidney cancer, liver cancer, lung cancer, cervical cancer, ovarian cancer, pancreatic cancer, prostate cancer, and gastric cancer; leukemia; benign and malignant lymphomas, particularly Burkitt lymphoma and non-Hodgkin lymphoma; benign and malignant melanoma; myeloproliferative disorders; sarcomas, particularly Ewing's sarcoma. Examples include angiosarcoma, Kaposi's sarcoma, liposarcoma, myosarcoma, peripheral neuroepithelioma, and synovial sarcoma; tumors of the central nervous system, such as glioma, astrocytoma, prostate cancer, cervical cancer, uterine cancer, lung cancer, ovarian cancer, testicular cancer, thyroid cancer, astrocytoma, esophageal cancer, pancreatic cancer, gastric cancer, liver cancer, colon cancer, and melanoma; mixed-type neoplasms, particularly carcinosarcoma and Hodgkin's disease; and tumors of mixed origin such as Wilms' tumor and teratocarcinoma (Beers and Berkow (eds.), The Merck Manual of Diagnosis and Therapy, 17th sup.th ed. (Whitehouse Station, NJ; Merck Research Laboratories, 1999) 973-74, 976, 986, 988, 991).

[0149] The term "cell receptor binding moiety" has the meaning recognized in the biomedical field. In some embodiments herein, the cell receptor binding moiety is an asialoglycoprotein receptor (ASGPR) binding group.

[0150] The term “cell receptor” has its recognized meaning in the biomedical field as referring to a compound, such as a ligand, in solution or on another cell, or a protein on the surface of a cell that binds to such a protein. Generally, ligand-receptor binding induces one or more biological responses. In this specification, asiaroglycoprotein receptors (ASGPRs) are cell receptors on the surface of hepatocytes or other cells that bind to asiaroglycoproteins or derivatives thereof.

[0151] The term "chemical properties, manufacturing, and control" (CMC) has a recognized meaning in the biomedical field of pharmaceutical quality, referring to several procedures used to evaluate the physical and chemical properties of drug products, ensure their quality and consistency during manufacturing, and prepare data for submission to regulatory authorities.

[0152] The term "chimerization" has a recognized meaning in the biomedical field. Chimeric antibodies are created by fusing a variable domain from one species, such as a mouse, with a constant domain from another species, such as a human. Using this bioengineering technique, chimeric antibodies retain the antigen specificity and affinity of the exogenous antibody.

[0153] The term "diabetes" has a recognized meaning in the biomedical field. See Wikipedia, the free encyclopedia, Dipeptidyl peptidase-4 inhibitor (online, accessed July 3, 2024). In type 1 diabetes, because insulin signals glucose uptake into cells, the destruction of insulin-producing β-pancreatic cells results in an inability to control blood glucose levels. Type 1 diabetes is a systemic disease that can lead to severe complications. High blood glucose is a symptom of diabetes. A person with diabetes is someone whose blood glucose levels are elevated or are expected to be elevated, and therefore desires to inhibit or lower blood glucose levels.

[0154] The term "diabetic macular edema" (DME) has a recognized meaning in the biomedical field of diabetic retinopathy. See Landry et al., Assay Drug Dev. Technol. 11(5), 326-32 (June 2013). Small bulges called microaneurysms form in blood vessels, causing fluid to leak into the retina.

[0155] (The term “dilated cardiomyopathy” (DCM) is defined as progressive cardiac diastolic and systolic dysfunction without coronary heart disease. Dilated cardiomyopathy can be caused by a humoral autoimmune response to β1 AR. (In contrast to ischemic heart failure, dilated cardiomyopathy generally affects younger people, with most patients being between 20 and 60 years of age. Idiopathic dilated cardiomyopathy often progresses to severe heart failure and may progress to the point where mechanical support with a left ventricular assist device or heart transplantation is required.)

[0156] The term "DMPK" has a recognized meaning in the biomedical field of drug metabolism and pharmacokinetics, which is a specialized field that helps identify drugs that are likely to be suitable for further development.

[0157] The term “drug product” generally, but not necessarily, has the U.S. Food and Drug Administration definition set out in 21 CFR §314.3 of a finished dosage form, e.g., a tablet, capsule, or liquid, that contains a drug substance together with one or more other ingredients.

[0158] The term “drug substance” has the definition of the active ingredient set out in 21 CFR §314.3 of the U.S. Food and Drug Administration, which is intended to produce pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment or prevention of a disease, or to affect the structure or any function of the human body, but does not include intermediates used in the synthesis of such an active ingredient.

[0159] The term "EC50" has a recognized meaning in the biomedical field as the ligand concentration required to achieve 50% of maximum receptor activation.

[0160] The term "Gal" has a recognized meaning in the biomedical field of galactose.

[0161] The term “galactose-deficient IgA1 (Gd-IgA1) binding moiety” has a recognized meaning in the biomedical field as referring to a binding protein that binds to galactose-deficient IgA1, such as an IgG antibody or a portion of its fragment. In some embodiments described herein, “glycan-specific IgG antibody binding moiety” is a galactose-deficient IgA1 binding moiety on an IgG antibody, such as a published Km55 antibody, a Km55 variant, or its antigen-binding fragment.

[0162] The term "GalNAc" refers to N-acetylgalactosamine, as recognized in the biomedical field.

[0163] The term "glomerular mesangium" has a recognized meaning in the biomedical field for the components of the renal glomerulus, forming the supporting skeleton from which the glomerular fasciculations and capillaries branch. The mesangium contains type IV collagen, proteoglycans, other proteins, and an extracellular matrix containing two cell types.

[0164] As used herein, the term "GN3" refers to the triaminogalactosyl moiety. Examples are provided herein.

[0165] The term "Good Laboratory Practice" (GLP) has a meaning provided by the U.S. Food and Drug Administration. See, for example, 21 CFR Part 58.

[0166] The term "Good Laboratory Practice" has the definition provided by the U.S. Food and Drug Administration in 21 CFR Part 58, Good Laboratory Practice for Nonclinical Studies.

[0167] The term "hepatocyte" has a recognized meaning in the biomedical field as referring to the cells of the major parenchymal tissue of the liver. Hepatocytes make up 55-65% of the liver's mass.

[0168] The term "humanization" has a recognized meaning in the biomedical field, meaning that a protein, such as an antibody, is genetically engineered to closely resemble the polypeptide structure of a human homolog. The variable domain of a rodent-derived antibody can be fused to a constant domain of human origin, thus preserving the specificity of the rodent antibody. The human-derived domain does not need to originate directly from humans, in that it is first synthesized in humans. Instead, the human domain can be generated in rodents whose genomes incorporate human immunoglobulin genes. Antibodies can be partially or completely humanized. In one approach, there are four common steps used to humanize a monoclonal antibody: these are (1) determining the nucleotide and predicted amino acid sequences of the light and heavy chain variable domains of the starting antibody; (2) designing the humanized antibody, i.e., determining which antibody framework regions to use during the humanization process; (3) the actual humanization methodology / technique; and (4) transfection and expression of the humanized antibody.

[0169] The term "IC50" has a recognized meaning in the biomedical field, referring to the amount, concentration, or dose of a particular test compound that achieves 50% inhibition of such a response in an assay measuring the maximum response.

[0170] The term "IgA antibody" has a recognized meaning in the biomedical field. Two IgA molecules bind to and associate with a protein that allows newly formed IgA molecules to be secreted across epithelial cells lining several tubules and organs.

[0171] The term "IgA nephropathy (IgAN)," also known as Berger's disease, is recognized in the biomedical field as the most common form of primary glomerulonephritis worldwide. This condition is named based on the pathological features of IgA deposition in the glomeruli. An estimated 15-20% of IgAN patients progress to end-stage renal disease within 20 years of disease onset. (Kuroyanagi et al., Galactose-deficient IgA1 is involved in IgA deposition in renal grafts biopsy 1 hour after kidney transplantation. Intern Med. October 26, 2022). IgA in mesangial deposits originates only from the IgA1 subclass, is abnormally glycosyl, and the O-linked glycans in the hinge region are deficient in galactose (Gal). Circulating IgA1 in IgAN patients also has Gal-deficient O-glycans, but Gal-deficient mutants are rarely found in serum IgA1 from normal individuals. The production of these mutants is due to altered expression of specific glycosyltransferases in IgA1-producing cells. Binding of IgA1-containing immune complexes with abnormally glycosylated IgA1 to mesangial cells induces kidney expression characteristic of IgAN. See Suzuki et al. Invest., 119, 1668-1677 (2009).

[0172] The term "IgG" antibody has a recognized meaning in the biomedical field. Each IgG molecule consists of a basic four-chain immunoglobulin structure—two gamma (γ) heavy chains and two identical light chains (either kappa or lambda)—and has two identical antigen-binding sites. There are four subclasses of IgG, each with slightly different H chains but distinct biological properties.

[0173] The term "IgG1" antibody has the meaning of an IgG antibody as recognized in the biomedical field, and the Igγ-1 chain C region is a protein encoded by the IGGH1 gene in humans.

[0174] The term "IgG2" antibody has a recognized meaning in the biomedical field of IgG antibodies, where the Igγ-2 chain C region is the protein encoded by the IGGH2 gene in humans.

[0175] The term "IgG4 antibody" has a recognized meaning in the biomedical field of IgG antibodies, where the Igγ-4 chain C region is encoded by the IGGH4 gene in humans. IgG4 has little effector function. IgG4 cannot fix complement.

[0176] The term “inflammatory disease” is used herein to describe diseases or illnesses that involve acute, but more often, chronic inflammation as the primary symptom of the disease or illness. Inflammatory diseases include, for example, neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and Huntington's disease; other ataxia, diseases of impaired immune response that cause inflammation, such as dysregulation of T cell maturation, B cell and T cell homeostasis, and counter-inflammation; chronic inflammatory diseases, such as inflammatory bowel disease, such as Crohn's disease, rheumatoid arthritis, lupus, multiple sclerosis, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, cystic fibrosis, and Sjögren's syndrome; hyperglycemic disorders, diabetes mellitus (I and II), pancreatic B-cell death and associated hyperglycemic disorders affecting lipid metabolism, pancreatic islet function and / or structure, such as severe insulin resistance, hyperinsulinemia, and insulin-dependent diabetes mellitus, such as Mendenhall syndrome and Werner syndrome. These include, among other things, leprosy and lipoatrophic diabetes, and dyslipidemia, e.g., hyperlipidemia expressed by obese subjects, elevated low-density lipoprotein (LDL), decreased high-density lipoprotein (HDL), elevated triglycerides, and metabolic syndrome, liver disease, kidney disease (apoptosis in plaque, glomerular disease), cardiovascular disease (in particular, including complications during infarction, ischemia, stroke, overpressure and reperfusion), muscle degeneration and atrophy, low-grade inflammation, gout, silicosis, atherosclerosis and related conditions, e.g., cardiac and neurological (both central and peripheral) symptoms including stroke, age-related dementia and sporadic Alzheimer's disease, as well as mental conditions including depression), stroke and spinal cord injury, and arteriosclerosis. In these diseases, elevated M1F is observed very frequently, and these disease conditions and / or states are made responsive to treatment using the compounds and / or pharmaceutical compositions according to the present invention. As described herein, there is some overlap between certain autoimmune diseases and inflammatory diseases.

[0177] The term "insulin growth factor" (IGF) has a recognized meaning in the biomedical field. Human IGF-1 means that human tissues contain the amino acid sequence corresponding to naturally occurring human IGF. Human IGF-1 may include fusion proteins.

[0178] The term "insulin receptor" has a recognized meaning in the biomedical field. The insulin receptor has two major subunits, α and β. Between the α and β subunits, there is a single disulfide crosslink between Cys647 and Cys872 in the insertion domain. The α subunit contains five major domains, L1 (AA 28-174), CR (AA 182-339), and L2 (AA 340-497), as well as two fibronectin subunits, FnIII-1 (residues 624-726) and FnIII-2 (757-842). The two α subunits are linked by four disulfide bonds. Insulin receptor β has different isoforms (IRA isoform and IRB isoform) depending on the gene splicing of exon 11. Insulin receptor B differs from insulin receptor A by containing exon 11. The 12-amino acid sequence (residues 745-756) derived from exon 11 is present in the insulin receptor B isoform but not in the insulin receptor A isoform. The isoforms have functionally distinct internalization and recycling processes. Insulin receptor A exhibits higher internalization and recycling rates than insulin receptor B. Insulin receptor A shows higher affinity for IGF than the IRB isoform. Both isoforms have similar affinities to insulin. Binding to these isoforms is quite different to proinsulin. Insulin receptor B is preferentially associated with metabolic and differentiation signaling. Insulin receptor A primarily functions favorably for cell growth, proliferation, and survival. See Beneit et al. Diabetol., 15, 161 (2016).

[0179] The term "insulin-like growth factor 2" (IGF-2) has a recognized meaning in the biomedical field as a well-characterized neutral peptide secreted by the liver for circulation in the blood. IGF-2 possesses growth-regulating, insulin-like, and mitotic activity.

[0180] The term "insulin" has a recognized meaning in the biomedical field. Insulin can be produced through chemical synthesis.

[0181] The term "KD" has a recognized meaning in the biomedical field as the measured equilibrium dissociation constant between a compound or ligand and a protein or protein binding domain.

[0182] In this specification, "Km55" refers to a group of anti-galactose-deficient IgA1 antibodies. In some embodiments, Km55 may be a published Km55 antibody, a Km55 variant, or an antigen-binding fragment thereof. In some embodiments, Km55 may be a chimeric, partially humanized, or humanized Km55 variant, or an antigen-binding fragment thereof.

[0183] The term "linker moiety" has a recognized meaning in the biomedical field as a part of a compound that links one part of the compound to another part of the same compound.

[0184] The term "Markush group" has the meaning recognized in patent law.

[0185] The term "modality" refers to a treatment method recognized in the biomedical field. See the National Cancer Institute's Dictionary of Cancer Terms.

[0186] The term "MoDE" has its own meaning in relation to the degrader platform described herein. MoDE degraders target a class of proteins involved in the pathogenesis of disease. MoDE is a registered trademark of Biohaven Therapeutics, Inc.

[0187] The term "MoDE" has its own meaning in relation to degraders. See International Patent Publications WO 2019 / 199634 (Yale University) and WO 2019 / 199621 (Yale University).

[0188] The term “part” has a biomedical meaning as a defined chemical group or entity having a specific structure or activity. Generally, a part refers to a portion of a molecule. In some embodiments, the binding part maintains one or more desired structural features, properties, functions, or characteristics, such as three-dimensional structure, antigen specificity, antigen-binding ability, or immunological function, comparable to its corresponding binding protein, e.g., an antibody. In some embodiments, the part is monovalent. In some embodiments, the part is divalent. In other embodiments, the part is polyvalent.

[0189] The term "multimodal antibody therapy enhancer (MATE)" has its own meaning. Intl. Publ.WO 2021 / 102052 (Kleo Pharmaceuticals).

[0190] The term “Multiple Elevated Dose” (MAD) has the meaning provided by the U.S. Food and Drug Administration. In a Phase Ib multiple escalation study to investigate the pharmacokinetics and pharmacodynamics of multiple doses of a drug to evaluate its safety and tolerability, a group of patients receives multiple low doses of the drug, while samples (blood and other body fluids) are collected at various time points and analyzed to obtain information on how the drug is processed in the body. The dose is then escalated to a predetermined level for subsequent groups. See Clinical Trial Types and Phases. American Cancer Society (August 18, 2020).

[0191] The term "neoplastic" has the meaning of a cancerous disease state recognized in the biomedical field and encompasses pathological processes associated with malignant hematogenous tumors, ascites tumors, and solid tumors.

[0192] The term "on top of" has a clear meaning. When an element is referred to as being on another element, that element may be in direct contact with the other element, or an intervening element may exist between them. When an element is referred to as being "directly on top of" another element, no intervening element exists.

[0193] As used herein, the term "or" includes any combination of one or more of the related enumerated items.

[0194] As used herein, the term “parenteral” includes subcutaneous, intravenous, intramuscular, intra-articular, intra-sacral, intrasternal, intrathecal, intrahepatic, intrafocal, and intracranial injection or infusion techniques.

[0195] The term "pathogenic protein" refers to a protein that can cause disease. It may be a misfolded, abnormal, or abnormal form of a protein that can induce disease. Pathogenic proteins can be extracellular or extravascular.

[0196] The term “pharmaceutically acceptable excipient” has the biomedical meaning of an excipient that is generally safe, non-toxic, and useful in preparing a pharmaceutical composition that is not biologically or otherwise undesirable, and includes excipients that are acceptable for veterinary and human pharmaceutically use. As used herein and in the claims, “pharmaceutically acceptable excipient” includes both one and more such excipients. A detailed discussion of pharmaceutically acceptable excipients is available in Remington's Pharmaceutical Sciences 23rd edition (Elsevier, 2020).

[0197] The term "pharmaceutically acceptable" has the meaning recognized in the biomedical field for a compound, anion, cation, material, composition, carrier, or dosage form that is suitable for contact with human and animal tissues without excessive toxicity, irritation, allergic reactions, or other problems or complications, and that is commensurate with a reasonable benefit / risk ratio, within the bounds of sound medical judgment.

[0198] The term "protein-binding region" is recognized in the biomedical field as meaning a region of a chemical composition that specifically binds to a protein, for example, a particular protein, or, for example, a polypeptide region of a chemical composition.

[0199] The term "ROC" has the recognized meaning in the biomedical field of receiver operating characteristic curve.

[0200] The term “Single-Dose Elevation Study” (SAD) has the meaning provided by the U.S. Food and Drug Administration. In a Phase Ia single-dose elevation study, a small group of subjects is administered a single dose of a drug, followed by observation and testing to assess the drug’s safety. See Clinical Trial Types and Phases. American Cancer Society (August 18, 2020).

[0201] The terms "subject" and "patient" have their recognized meanings in the biomedical field. The term "patient" includes human and other mammalian subjects receiving either prophylactic or therapeutic treatment.

[0202] The term "TBT" has the meaning recognized in the biomedical field as a cell receptor binding moiety. In some embodiments herein, TBT binds to ASGPR.

[0203] The term "TRAP" has the meaning described herein of an agent for targeted removal of proteins. TRAP is a bifunctional degrading agent.

[0204] The term "TRAP" has its own meaning in relation to the degrader platform described herein. TRAP degraders remove proteins that cause specific abnormal diseases while leaving healthy components of the immune system intact. For example, Compound 1 is a precision tool that removes only the disease-causing entities and then degrades IgA more deeply, rapidly, and potentially without the off-target effects of less precise treatment. TRAP is a registered trademark of Biohaven Therapeutics, Inc.

[0205] The term "adverse event occurring under treatment" refers to any event that did not exist before the initiation of drug treatment, or any pre-existing event that worsens in either intensity or frequency after exposure to drug treatment.

[0206] The term "tumor" has a recognized meaning in the biomedical field.

[0207] The term "type 1 diabetes" has a recognized meaning in the biomedical field as a chronic autoimmune disease that occurs when the immune system attacks insulin-producing cells in the pancreas, leading to the autoimmune eradication of beta cells in the pancreatic islets. Insulin can no longer be synthesized or secreted into the bloodstream. Other autoantibodies directed at islet cells may also be present in patients with type 1 diabetes.

[0208] The term "type 2 diabetes" has a recognized meaning in the biomedical field as the progressive loss of insulin receptors that induce hyperglycemia. Hyperglycemia is compensated for by inducing increased insulin production by beta cells. The accumulation of amyloid in the pancreatic islets is likely to disrupt the anatomical structure and physiological function of the islets. Ultimately, beta cells become depleted, leading to a decrease in insulin over time.

[0209] The terms “effective dose” and “therapeutic effective dose” have the recognized meaning in the biomedical field of an amount effective in achieving its intended purpose. This effect can be detected by any assay method known in the biomedical field. The exact effective dose of a subject depends on the subject’s weight, size, and health condition; the nature and degree of the condition; and the therapeutic agent or combination of therapeutic agents selected for administration. The therapeutic effective dose for a given situation can be determined by routine experiments, which are within the scope of the clinician’s skill and judgment.

[0210] As used herein, the terms “comprises” and / or “comprising,” or “includes” and / or “including,” specify the presence of the described features, regions, integers, steps, actions, elements, and / or components, but do not exclude the presence or addition of one or more other features, regions, integers, steps, actions, elements, components, and / or groups thereof.

[0211] The terms “equipped,” “containing,” and “containing” specify the presence of the described feature, region, integer, step, operation, element, or component, but do not exclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, or groups thereof.

[0212] The terms “to treat” and “to heal” have the recognized meaning in the biomedical field of managing and caring for a patient in order to combat a disease, condition, or disorder. To treat includes administering the compositions described herein to alleviate the symptoms or complications of a disease, condition, or disorder, or to eliminate a disease, condition, or disorder.

[0213] This specification does not relate to the process of cloning humans, the method of altering the genetic identity of human germlines, the use of human embryos for industrial or commercial purposes, or procedures for altering the genetic identity of animals (which may cause suffering to animals) that do not involve substantial medical benefits to humans or animals resulting from such processes.

[0214] Additional aspects are partially described in the following explanation and should be evident from that explanation. Introduction and principle for subcutaneous administration

[0215] Targeted elimination of extracellular protein degraders and abnormal protein degraders according to embodiments of the present invention delivered by subcutaneous injection provides significantly enhanced immunoglobulin reduction (pharmacodynamic efficacy) compared to intravenous injection. This phenomenon intentionally utilizes a novel combination of multiple properties unique to this extracellular degradation platform for subcutaneous delivery of biologics, as well as for antibody production, distribution, and recirculation in the body, enabling simultaneous elimination of intravascular and extravascular antibody or protein targets. As with many biologics, when administered subcutaneously, the adsorption of the degrader occurs first via diffusion into the lymphatic circulation, followed by delivery into the venous and ultimately systemic circulation.

[0216] Immunoglobulins are primarily produced within lymph nodes, and lymphoid plasma cell infiltrations in tissues are drained into the circulatory system via lymphatic vessels. Leveraging the common properties of the target and drug, subcutaneous administration according to this invention allows for early saturation of MoDE or TRAP binding sites by immunoglobulins. Since the majority of the body's lymphatic vessels flow into the thoracic duct, the subcutaneous injection site and antibody production site do not need to be in the same location. Lymphatic flow from both the injection site and the antibody target leads relatively undiluted drugs and drug targets to a common anatomical confluence for mixing and high-affinity binding by MoDE or TRAP in the thoracic duct before systemic dissemination. This directed target-mediated pharmacokinetic (TMDD) ensures that the immunoglobulin-containing MoDE or TRAP is delivered to the hepatic ASGPR with maximum efficiency, thereby ensuring that the “first pass” of the drug not bound by the target is cleared by the liver. Planned extravascular targeting of immunoglobulin capture in lymphatic vessels, as well as this mechanism for avoiding hepatic first-pass clearance, is novel and unprecedented. The combination of these two novel approaches (one for the drug to capture the target and the other for the drug to avoid first-pass) resulted in unprecedented pharmacodynamic efficiency for subcutaneously delivered MoDE and TRAP degraders.

[0217] A molar excess of the drug exceeding the antibody concentration in the lymphatic vessels ensures that a calibrated proportion of the unbound drug is also delivered into the bloodstream. This delivery occurs at the confluence of the thoracic lymphatic vessels and the subclavian vein, from which the drug is dispersed into the systemic circulation. This free molar excess then binds to free intravascular immunoglobulins, which are subsequently removed by the liver. The drug dose is designed to set a precisely measured molar excess to optimize both extra-lymphatic and intravascular binding of immunoglobulins and minimize first-pass clearance.

[0218] All other classes of therapeutic agents that reduce circulating immunoglobulins do so by removing intravascular components accompanied by a stepwise reduction of extravascular immunoglobulins through equilibration of the intravascular and extravascular compartments, or by cytotoxic targeting of plasma cells or their precursor B cells accompanied by systemic immunosuppression. Biohaven's MoDE and TRAP degraders demonstrate significantly accelerated kinetics of pathogenic antibody reduction by directly accessing both compartments, which is expected to result in a corresponding slowing of the associated disease process. B-cell targeted therapies or therapies that reduce all IgG subclasses have shown immunosuppression with chronic use. The enhanced efficacy of MoDE and TRAP degraders is expected to occur without immunosuppression, conditioned on simultaneous intravascular and extravascular antibody targeting and depletion. Degrader (two-function degrader)

[0219] In one embodiment, the IgG degrading agent ("IgG degrading agent") may have the following general chemical structure. [ka] [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via asialoglycoprotein receptors or other receptors identified herein, which are present on the surface of hepatocytes and other degraded cells (the compound preferably selectively binds to IgG in the plasma of the subject or the subject); [CON] is, respectively, an optional linking chemical moiety that directly links to [CPBM] or [CRBM], or links [LINKER] to [CPBM] or [CRBM], and

[0220] [LINKER] is a chemical moiety having a valency of 1 to 15, which is covalently bonded to one or more [CRBM] and / or [CPBM] groups, optionally via [CON] (including a [MULTICON] group), where the [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself; k' is an integer from 1 to 15; j' is an integer from 1 to 15; h and h' are each independently integers from 0 to 15; iL is an integer from 0 to 15; however, at least one of h, h' and iL is at least 1, the compound, or a pharmaceutically acceptable salt, stereoisomer, solvate or polymorph thereof.

[0221] Various IgG binding moieties [CPBM], cell receptor binding moieties [CRBM], and linking groups [LINKER] and [CON] are publicly known in the biomedical field, for example, in International Publication WO 2019 / 199634, published on 17 October 2019, and the contents of these publications are incorporated herein by reference in their entirety.

[0222] In one embodiment, the degrading agent may be an immunoglobulin G ("IgG") degrading agent. In such embodiments, [CPBM] may be an immunoglobulin G binding moiety [IgGBM] having the structure: [ka] [ka] or (v)PAM;D-PAM;D-PAM-Φ;TWKTSRISIF(SEQ ID NO: 1);FGRLVSSIRY(SEQ ID NO: 2);FcIII;FcBP-1;FcBP-2;Fc-III-4c;EPIHRSTLTALL(SEQ ID NO: 3);APAR(SEQ ID NO: 4);FcRM;HWRGWV(SEQ ID NO: 5);HYFKFD(SEQ ID NO: 6);HFRRHL(SEQ ID NO: 7);HWCitGWV(SEQ ID NO: 8);D2AAG;DAAG;cyclo[(N-Ac)S(A)-RWHYFK-La A peptide moiety selected from the group consisting of ct-E](sequence number 9);cyclo[(N-Ac)-Dap(A)-RWHYFK-Lact-E](sequence number 10);cyclo[Link-M-WFRHYK](sequence number 11);NKFRGKYK(sequence number 12);NARKFYKG(sequence number 13);FYWHCLDE(sequence number 14);FYCHWALE(sequence number 15);FYCHTIDE(sequence number 16);RRGW(sequence number 17); and KHRFNKD(sequence number 18); [CRBM] may also be a cell receptor binding moiety having the structure: [ka] ; Each [CON] is independent of its occurrence. [ka] [LINKER] may have the structure: [ka] K''' can be 1, 2, 3, or 4. RM can be H or C1-C3 alkyl. X1 may be O; Each occurrence of X2 can independently be CH2, O, NR4, or C(O); The presence of R1 and R4 can independently be H or C1-C3 alkyl. ZB is either nonexistent (bonded), -(CH2)IM-, -C(O)-(CH2)IM-, or -C(O)-(CH2)IM-NRM-; Each occurrence of IM can independently be 1, 2, or 3; k' can be 1; Each occurrence of j can independently be 1, 2, 3, 4, or 5; j' can be 1; h and h' are independently 1, 2, 3, 4, 5, 6, 7, or 8. iL may also be 1; Each occurrence of n can be 2 or 3 independently; Each occurrence of n'' can be 2, 3, 4, or 5 independently; or its salt, stereoisomer, or solvate.

[0223] In other embodiments, h and h' may each be independently 1, 2, 3, 4, or 5.

[0224] In another embodiment, each presence of X2 can independently be CH2, NR4, or C(O); R1 can be H; and R4 can be H.

[0225] In another embodiment, ZB may be absent or may be -C(O)-(CH2)IM-.

[0226] In another embodiment, [CPBM] may be [IgGBM] of the structure: [ka] (Sequence ID 19).

[0227] In another embodiment, [CPBM] may be [IgGBM] of the structure: [Chemistry]

[0228] In another embodiment, [CPBM] may be [IgGBM] of structure: [Chemistry]

[0229] In another embodiment, [CPBM] may be [IgGBM] of structure: [Chemistry]

[0230] In another embodiment, [CPBM] may be [IgGBM] of structure: [Chemistry] [Chemistry] (SEQ ID NO: 19).

[0231] In another embodiment, the compound may have the structure: [Chemistry] or [Chemistry]

[0232] In another embodiment, the compound may have the structure: [Chemistry]

[0233] [Chemistry]

[0234] In another embodiment, the compound may have the structure: [Chemistry]

[0235] In another embodiment, the compound may have the structure: [Chemistry]

[0236] In another embodiment, the compound may have the structure: [Chemistry]

[0237] In another embodiment, the TM degrader may be a degrader of immunoglobulin A ("IgA"). Examples of such degraders are described in International Publication No. 2022 / 192478 published on September 15, 2022, and International Publication No. 2024 / 228935 published on November 7, 2024, the contents of these publications being incorporated herein by reference in their entirety.

[0238] In another embodiment, the degrader may be a degrader of an antibody against the thyroid-stimulating hormone receptor ("TSHR"). Examples of such degraders are described in International Publication No. 2024 / 155750 published on July 25, 2024, the contents of that publication being incorporated herein by reference in its entirety.

[0239] In another embodiment, the degrading agent may be a degrading agent for anti-β1 ECII autoantibodies. Examples of such degrading agents are described in International Publication No. 2023 / 028590, published on March 2, 2023, and International Publication No. 2023 / 028597, published on March 2, 2023, the contents of which are incorporated herein by reference in their entirety.

[0240] In another embodiment, the degrading agent may be a pathogenic protein degrading agent that is an immunoglobulin D ("IgD") degrading agent.

[0241] In another embodiment, the degrading agent may be a pathogenic protein degrading agent that is an immunoglobulin E ("IgE") degrading agent.

[0242] In another embodiment, the degrading agent may be an immunoglobulin M ("IgM") degrading agent, which is a degrading agent for pathogenic proteins.

[0243] In one embodiment, the decomposition agent may have one of the following general chemical structures. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0244] R2 is NHC(=O)CH3;

[0245] R5 is CH2OH;

[0246] Extracellular protein-targeting ligands may be ligands that have affinity for extracellular or extravascular pathogenic proteins.

[0247] Linker A may also be a chemical group that connects the ASGPR ligand to linker B, linker C, or linker D;

[0248] Linker B may also be a chemical group that connects linker A to a pathogenic protein targeting ligand;

[0249] Linker C may also be a chemical group that connects linker C to a pathogenic protein targeting ligand; and

[0250] Linker D may be a chemical group that connects linker A to a pathogenic protein targeting ligand.

[0251] In the above formula, “pathogenic protein-targeting ligand” refers to a pathogenic protein-binding moiety [CPBM] that binds to a pathogenic form of an extracellular or extravascular protein identified herein, which is associated with and / or mediates a disease state, and is removed by the action of hepatocytes or other cells on the circulating protein (the compound preferably selectively binds to IgG in the plasma of the subject or patient).

[0252] In the above formula [ka] [ka] [ka]

[0253] Various parts [linker A], [linker B], [linker C], [linker C], [ring], and X1, as well as the part that binds to pathogenic proteins, are known in the biomedical field and are described, for example, in International Publication WO 2021 / 155317 published on 5 August 2021, International Publication WO 2022 / 035997 published on 17 February 2022, International Publication WO 2022 / 235699 published on 10 November 2022, International Publication WO 2023 / 009554 published on 2 February 2023, and International Publication WO 2023 / 028338 published on 2 March 2023, the contents of these publications are incorporated herein by reference in their entirety. How to make a dual-function degrader

[0254] Starting materials useful for producing the pharmaceutical compositions of the present invention are readily available commercially or can be prepared by those skilled in the biomedical field.

[0255] Other methods for producing the bifunctional decomposition agents disclosed herein may be found in published patent applications.

[0256] The method for producing compound 1 is disclosed in International Publication No. 2024 / 228935 (Biohaven Therapeutics). A method for removing pathogenic proteins from a subject or patient.

[0257] The best mode of administration for a bifunctional decomposing agent depends on where the procedure is performed, whether in a hospital or on an outpatient basis.

[0258] The removal of pathogenic proteins from a subject or patient is known to those skilled in the biomedical field and can be measured by the methods disclosed herein. Methods of treating diseases

[0259] The pathogenic protein degraders disclosed herein may be useful in treating cancer. Neoplasms can be treated using compounds according to embodiments of the present invention.

[0260] Representative common cancers treated with the compounds of the present invention include, for example, prostate cancer, metastatic prostate cancer, stomach, colon, rectum, liver, pancreas, lung, breast, cervix, uterine body, ovary, testis, bladder, kidney, central nervous system, head and neck, throat, Hodgkin's disease, non-Hodgkin lymphoma, multiple myeloma, leukemia, melanoma, non-melanoma skin cancer, acute lymphoblastic leukemia, acute myeloid leukemia, Ewing's sarcoma, small cell lung cancer, choriocarcinoma, rhabdomyosarcoma, Wilms' tumor, neuroblastoma, hairy cell leukemia, oral / pharyngeal, esophageal, laryngeal, kidney cancer, and lymphoma, which can be treated with one or more compounds of the present invention. Due to the activity of the compounds of the present invention, the present invention has general applicability to treat substantially any cancer in any tissue, and therefore the compounds, compositions, and methods of the present invention are generally applicable to the treatment of cancer, as well as to reducing the likelihood of cancer development and / or metastasis of existing cancer.

[0261] In some embodiments of the present invention, the cancers to be treated are metastatic cancers, recurrent cancers, or drug-resistant cancers, particularly multidrug-resistant cancers. Separately, metastatic cancers can be found in substantially any tissue of cancer patients in the later stages of the disease, and typically, metastatic cancers can be found in substantially any tissue, including the lymphatic system / lymph nodes (lymphoma), bone, lungs, bladder tissue, kidney tissue, liver tissue, and brain (brain cancer / tumors). Thus, embodiments of the present invention are generally applicable and can be used to treat any cancer in any tissue, regardless of etiology.

[0262] The pathogenic protein degraders disclosed herein may be useful for treating autoimmune diseases. A more complete list of autoimmune diseases that can be treated by compounds and pharmaceutical compositions according to embodiments of the present invention includes: Addison's disease, autoimmune polyendodrine syndrome (APS) types 1, 2, and 3, autoimmune pancreatitis (AIP), diabetes mellitus type 1, autoimmune thyroiditis, Ord's thyroiditis, Graves' disease, autoimmune oophoritis, endometritis, autoimmune orchitis, Sjögren's syndrome, autoimmune enteropathy, celiac disease, Crohn's disease, microscopic colitis, ulcerative colitis, autophospholipid syndrome (APIS), aplastic anemia, autoimmune hemolytic anemia, autoimmune lymphoproliferative syndrome, autoimmune neutropenia, autoimmune thrombocytopenic purpura, cold agglutinin disease, adult-onset Still's disease, ankylosing spondylitis, CREST syndrome, drug-induced lupus, enthesitis-related, esosiniphilic fasciitis, Felty syndrome, AgG 4 related diseases, juvenile arthritis, Lyme disease (chronic), mixed connective tissue disease (MCTD), relapsing rheumatoid arthritis, Parry-Romberg syndrome, Personage-Turner syndrome, psoriatic arthritis, myasthenia gravis, neuromyositis, paraneoplastic cerebellar degeneration, polymysositis, acute disseminated encephalomyelitis (ADEM), acute motor axonal neuropathy, anti-NMDA receptor encephalitis, barofibromyalgia, myositis, inclusion body myositis, myasthenia gravis, neuromyositis, Schnitzler syndrome, systemic lupus erythematosus, undifferentiated connective tissue disease (UTCD), dematomyositis, fibromyalgia, myositis, inclusion body myositis, myasthenia gravis, neuromyositis, paraneoplastic cerebellar degeneration, acute disseminated encephalomyelitis (ADEM) M), acute motor axonal neuropathy, anti-NMDA receptor encephalitis, Baro fibromyalgia, Stiff Mann syndrome, inclusion body myositis, autoimmune retinopathy, rheumatoid arthritis, pattern 11, Oshtoran syndrome, pendiatric autoimmune neuropsychiatric disorder-associated streptococcus (PANDAS), progressive inflammatory neuropathy, restless limb syndrome, Baro fibromyositis, myositis, inclusion body myositis, rheumatoid arthritis, rheumatoid arthritis, chronic autoimmune demyelinating neuropathy, Guillain-Barré syndrome, Hashimoto's disease, idiopathic inflammatory demyelinating disease, Lambert-Eaton myasthenic syndrome, multiple sclerosis, pattern 11, pattern 11, pattern 11, pattern 11, pattern 11, pattern 11,Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern 11, Pattern For example, interstitial lung disease, POEMS syndrome, Raynaud's syndrome, primary immunodeficiency and pyoderma gangrenosum. Opsoclonus, pure red cell womb, relapsing polychondritis, Evans syndrome, Tolosa esopagitis, intermediate uveitis, Cogan syndrome, Bickerstaffs cryoglulinemia,

[0263] The pathogenic protein degraders disclosed herein may be useful in treating inflammatory diseases. Reduction of pathogenic protein levels by contacting components of the extravascular system.

[0264] The lymphatic system generally comprises a network of blood vessels separated from veins and arteries. Lymphatic vessels carry lymph fluid, rather than whole blood. The lymphatic system serves a variety of physiological purposes, including returning interstitial fluid to vascular space, transporting fats from the digestive tract, and transporting immune-mediated cells. The composition of lymph fluid is similar to that of plasma. It contains white blood cells but generally does not contain red blood cells, platelets, or various other components of whole blood. The lymphatic system can be involved in a variety of pathological conditions, including lymphatic obstruction leading to lymphedema, lymphatic leakage that can lead to mastitis, or infiltration and diffusion of malignant cells leading to metastasis. The lymphatic system is involved in almost any immune-mediated response, whether against malignant tumors or in situations of autoimmune disorders, involving infectious agents such as viruses, bacteria, and parasites. The lymphatic system can function as a reservoir of infected cells in disease or may contain higher concentrations of dysfunctional cells in various immune system disorders. Accessing the lymphatic system may be desirable to achieve the diagnosis and / or treatment of these and other conditions.

[0265] In one embodiment, the present invention provides a method for reducing the level of pathogenic proteins in a subject, comprising contacting a component of the extravascular system of the subject with (i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the subject, and (ii) a degrading agent having affinity for pathogenic proteins, in an amount effective in promoting the reduction of the level of pathogenic proteins in the subject.

[0266] The components of the lymphatic system may be lymph, lymphatic vessels, lymph nodes, and lymphatic organs. Lymphatic organs may be the thymus, spleen, tonsils, bone marrow, or Peyer's patches. Method of administration of degrader and variability of pharmacokinetics / pharmacodynamics

[0267] The compositions of the present invention may be formulated in a conventional manner using one or more pharmaceutically acceptable carriers, or may be administered in a controlled-release formulation. Examples of pharmaceutically acceptable carriers that may be used in these pharmaceutical compositions include, but are not limited to, ion exchangers, alumina, aluminum stearate, lecithin, serum proteins such as human serum albumin, buffers such as phosphates, glycine, sorbic acid, potassium sorbate, partial glyceride mixtures of saturated vegetable fatty acids, water, prolamin sulfate, disodium hydrogen phosphate, potassium hydrogen phosphate, sodium chloride, zinc salts, colloidal silica, magnesium trisilicate, polyvinylpyrrolidone, cellulosic substances, polyethylene glycol, sodium carboxymethylcellulose, polyacrylates, waxes, polyethylene-polyoxypropylene-block polymers, polyethylene glycol, and salts or electrolytes such as wool fat.

[0268] The compositions of the present invention can be administered, in particular, parenterally, orally, by inhalation spray, topically, rectally, nasally, buccally, vaginally, or via an implanted reservoir. Preferably, the compositions are administered subcutaneously.

[0269] The inventors unexpectedly discovered that different methods of administering the degrading agent resulted in different degrees of reduction in pathogenic protein. As described in the following examples, intravenous administration of the degrading agent resulted in a rapid and potent reduction in pathogenic protein levels, while subcutaneous administration resulted in a sustained, longer-lasting reduction in degrading agent levels.

[0270] The reduction in pathogenicity levels in the target may be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

[0271] The aforementioned reduction in pathogenic protein levels may persist for at least 10 hours, at least 20 hours, at least 30 hours, at least 40 hours, at least 50 hours, at least 60 hours, at least 70 hours, at least 80 hours, at least 90 hours, or at least 100 hours after administration. Examples

[0272] The present invention is further described by non-limiting embodiments. Example 1 Subcutaneous administration of FCIII-GN3 resulted in a deep, rapid, and controllable reduction of pathogenic IgG.

[0273] This example demonstrates that subcutaneous administration of FCIII-GN3 achieves deep, rapid, and adjustable IgG reduction, customized to the specific needs of IgG-related diseases.

[0274] FCIII-GN3 is a bispecific, small molecule with a relatively short half-life, designed to selectively and transiently reduce IgG via intravenous or subcutaneous injection. The molecule consists of a peptide IgG conjugate, a short PEG linker, and a GalNac ASGPR conjugate for targeting IgG for hepatic lysosomal degradation. FCIII-GN3 is specifically designed to mediate the formation of a ternary complex between target proteins (particularly human IgG1, IgG2, and IgG4) and ASGPR, which is abundantly expressed on hepatocytes. FCIII-GN3 is designed to selectively and transiently target IgG subclasses IgG1, IgG2, and IgG4 while preserving subclass IgG3. IgG3 preservation by FCIII-GN3 is expected to maintain robustness of host defense against a given degree of IgG reduction and may offer advantages compared to agents that reduce all IgG subclasses, such as FcRn-targeted antibody fragments. Based on key mechanistic advantages, including rapid onset of IgG reduction, reduced time to maximum effect, depth of IgG reduction, short exposure duration, potential for reduced immunosuppression given the lack of effect on IgG3, potential for low immunogenicity, ability to be administered concurrently with biologics, and lack of effect on albumin, cholesterol, or triglycerides, FCIII-GN3 potentially offers significantly improved benefit-risk for treating IgG-mediated diseases.

[0275] FCIII-GN3 has improved benefit-risks for use in immune-mediated diseases. FCIII-GN3 has been safely administered to humans as a single intravenous and subcutaneous dose up to 500 mg. For further details, please refer to the FCIII-GN3 Investigator's Brochure.

[0276] In vitro and in vivo non-clinical studies demonstrated FCIII-GN3 binding to ASGPR CRD and human IgG subclasses. Concentration-dependent FCIII-GN3-mediated uptake of IgG into HepG2 cells and human primary hepatocytes was observed. Safety pharmacological evaluations showed no dose-dependent adverse effects of FCIII-GN3 on the central nervous system, respiratory system, or cardiovascular system. Potential effects of FCIII-GN3 on the central nervous system, respiratory system, and cardiovascular system were evaluated in studies following Good Laboratory Practice regulations and ICH guidelines. In cynomolgus monkeys, FCIII-GN3 at doses up to 500 mg / kg did not produce findings in functional observational battery assessments, electrocardiograms, hemodynamics, or respiratory function parameters. In hERG assays, the median inhibitory concentration (IC50) was 2191.1 μM. These results do not indicate significant human risk.

[0277] In this example, the IgG degrading agent (500 mg) FCIII-GN3 (see Figure 15) was administered subcutaneously ("SC") to the patient.

[0278] (The results are shown in Figures 1-7. These figures show that the peak did not occur until the 6-12 hour range (relative to the first time point after intravenous infusion). The peak was only less than 20% lower than after intravenous infusion, despite a much later Tmax. Subcutaneous drug concentrations exceeded intravenous infusion drug concentrations until the last measurable time point, which began 12 hours after infusion. Bioavailability was at least 30% higher on average with subcutaneous infusion compared to intravenous infusion (including at the 24-hour point). In this case (a nonlinear system with target-mediated pharmacokinetics), target-mediated pharmacokinetics are somewhat prolonged after subcutaneous administration. Subcutaneous administration may result in mechanistically improved pharmacodynamics for all degraders of pathogenic proteins.)

[0279] This embodiment demonstrates a dose-dependent, rapid IgG reduction with favorable safety and a profile suitable for subcutaneous administration. See Figure 8.

[0280] FCIII-GN3 is a small molecule with a short half-life. FCIII-GN3 can be administered more frequently as needed, or on the same day as biologics. Due to its short half-life and direct mechanism, FCIII-GN3 exerts its effects and is then rapidly removed from the circulation while its pharmacodynamic effect persists. This activity means a shorter duration of off-target effects, resulting in a prolonged reduction of disease-causing proteins. Subcutaneous administration of FCIII-GN3 provides a long-lasting effect after the last dose.

[0281] Care providers, such as physicians, can increase the FCIII-GN3 dose early to achieve a more rapid reduction in IgG levels in the patient. Care providers can maintain reduced IgG levels with less frequent administration. Dosage may vary depending on the specific IgG-related disease. The curve is important to understand. We will show a little more about how a faster response, which may be important for signs like acute MG, can be achieved.

[0282] Subcutaneous injection of 2000 mg of FCIII-GN3 achieved a mean maximum reduction of 81% in total IgG by day 18.

[0283] 2000 mg of FCIII-GN3 provides a mode for managing acute illness by reducing IgG as rapidly and deeply as plasmapheresis. Administration of FCIII-GN3 to humans in clinical trials

[0284] The completed dose cohort of FCIII-GN3 was administered intravenously at doses of 50 mg, 125 mg, 250 mg, and 500 mg. FCIII-GN3 was also administered subcutaneously at a dose of 500 mg. No serious adverse events were observed. Most adverse events were unrelated to FCIII-GN3. The clinically significant trend was electrocardiogram-laboratory results.

[0285] Subcutaneous cohort. High subcutaneous bioavailability accompanied by decreased IgG levels and injection volumes suitable for auto-injectors were confirmed.

[0286] Pharmacokinetics (confirming high subcutaneous bioavailability: AUC = 144%, Cmax = 80% compared to intravenous).

[0287] Pharmacodynamics (shows significant IgG reduction; 4 / 6 subjects exhibit approximately 40-60% IgG reduction within 96 hours; low injection volume suitable for automated injectors).

[0288] Subcutaneously administered FCIII-GN3 achieved a significant reduction in targeted IgG, with a decrease of over 60% at the lowest subcutaneous dose tested in the multi-escalation dose study. Subcutaneous FCIII-GN3 administration achieved a progressive decrease in IgG within hours of each weekly dose in the multi-escalation dose study, and the pharmacodynamic effect persisted against baseline over the 4-week study period. FCIII-GN3 was safe and well-tolerated throughout this study. There were no clinically significant effects on albumin or liver function, and no increase in cholesterol was observed. Further enhancing the competitive safety profile, as intentionally designed, plasma IgG3 levels were preserved until the end of week 4 of the study, enabling healthy immune effector function. All adverse events were mild, any drug-related adverse events resolved, and there were no study drug-related adverse event-related discontinuations. The optimized subcutaneous formulation in the multi-escalation dose study also showed substantially less patient variability compared to previously reported intravenous FCIII-GN3. A subcutaneous FCIII-GN3 dose-escalation cohort is underway to explore the full range of IgG reductions possible with FCIII-GN3 for a broad range of future disease indications.

[0289] FCIII-GN3 is a small molecule, a potential first-in-class extracellular IgG degrader, rationally designed to selectively target and remove IgG1, IgG2, and IgG4, the root causes of disease, by leveraging the body's natural hepatic clearance mechanisms. FCIII-GN3 conserves IgG3, preserving the patient's immune defense against bacteria, viruses, and parasites. The results of this embodiment confirm that FCIII-GN3 produces a significant reduction in total IgG, is selective, conserves IgG3, is moduloable, safe, and well-tolerated.

[0290] In the example, FCIII-GN3 administered subcutaneously at a dose of 2000 mg weekly achieved an IgG reduction of up to 85%, with a maximum median reduction of 81% by day 17. Biohaven recently reported that a weekly dose of 1000 mg achieved a rapid, deep, and sustained reduction of total IgG up to 84%, with an 80% median reduction. See Figures 11-14. The reduction at all doses, which occurred within hours of administration, was progressive, and the effect persisted between dosing intervals. The range of IgG reductions enabled by different FCIII-GN3 dose levels provides adjustability and flexibility in the dosing paradigm, using higher doses planned for the management of acute conditions and lower, less frequent dosing planned for the management of chronic diseases.

[0291] FCIII-GN3, administered at 1000 mg weekly, has a short half-life and a durable IgG decline lasting several months. Compared to placebo, FCIII-GN3 was safe and well-tolerated at subcutaneous doses up to 2000 mg over a 4-week treatment period without clinically significant increases in ALT, AST, or bilirubin, clinically significant decreases in albumin, or clinically significant increases in cholesterol. There were no clinically significant decreases in any of IgG3, IgA, IgD, IgE, or IgM compared to baseline. Most adverse events were mild and self-resolving. There were no serious or severe adverse events.

[0292] Optimization of the FCIII-GN3 Placebo-Controlled Study: Evaluation of Single and Multiple Dose Subcutaneous Formulations This example describes a placebo-controlled, single-dose and multiple-dose study consisting of two parts. Part 1 included three single-dose cohorts. Part 2 included four multiple-dose cohorts.

[0293] The study population consisted of approximately 64 adult men and non-pregnant women. The planned dose range across Part 1 and Part 2 cohorts was 500–2000 mg of BHV 1300 or placebo.

[0294] FCIII-GN3 was administered subcutaneously to the abdomen of the subjects. FCIII-GN3 was provided at 250 mg / mL in a colorless, clear solution that was essentially free of visible particulate matter. Each vial contained an extractable volume of 3 mL (750 mg). The corresponding placebo for FCIII-GN3 was 0.9% physiological saline, a homogeneous, clear, colorless liquid.

[0295] The primary objective of this example was to evaluate the safety and tolerability of FCIII-GN3 after single and multiple dose subcutaneous administration. A second objective of this example was to assess the pharmacokinetic profiles of FCIII-GN3 after single and multiple dose subcutaneous administration. Other objectives of this example were to characterize the pharmacokinetic results of FCIII-GN3 after single and multiple dose subcutaneous administration, to characterize FCIII-GN3 binding to plasma proteins, to assess the immunogenicity of FCIII-GN3 after single dose electrocardiogram, and to characterize urine for pharmacokinetics of a single FCIII-GN3 dose.

[0296] For the assay of the primary endpoint in this example, safety and tolerability were assessed for adverse events. For the assay of the secondary endpoint in this example, (1) for day 1 of Part 1 and Part 2, AUC0-72 hours (Part 2b), AUC0-96 hours (Part 1 and Part 2a), AUCinf, Cmax, Tmax, T1 / 2, CL / F, Vd / F; (2) for day 22 of Part 2, AUC0-72 hours (Part 2b), AUC0-96 hours, AUCinf, Cmax, Tmax, T1 / 2, RAAUC0-96 hours, RACmax, CL / F, Vd / F.

[0297] For the assay during Part 1 of the single dose escalation in this example, 1) a total of 15 blood samples were collected for pharmacokinetic analysis at pre-administration, 0.33 hours, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, 96 hours, and 168 hours (Day 8), relative to the end of the injection administration time on Day 1. (2) Plasma samples were collected and analyzed for protein binding after administration on Day 1, at 6 hours and 48 hours after the end of the injection time. (3) Pharmacodynamic blood samples for the following tests were collected at the following times: (a) Total IgA, IgE, and IgM assayed on day 1 before administration, day 1 before administration, 96 hours, and day 36; (b) Subclasses IgG1, IgG2, IgG3, and IgG4 assayed on day 1 before administration, day 1 before administration, 4 hours, 8 hours, 24 hours, 48 ​​hours, 72 hours, 96 hours, and on days 8, 15, 22, 29, and 36. (c) Total IgG; (d) Immune complex C3 was circulated before administration, at 4, 24, 48, and 72 hours, and on days 8, 22, and 29; (e)(f) Bank serum was collected before administration, at 24, 72, and 96 hours on day 1, and on days 15 and 36. (4) For pharmacokinetic analysis, pharmacokinetic urine samples were collected on day 1 at the following intervals: 0-4 hours, 4-8 hours, 8-12 hours, 12-24 hours, 24-48 hours, 48-72 hours, and 72-9 hours post-administration. (5) Standard biochemistry, HbA1c on the initial screening day, hematological and urinalysis on days 1, 2, 4, 5, 8, 15, 22, 29, and 36.

[0298] For the multi-dose escalation Part 2 assay of this embodiment, 1) 32 blood samples were collected for pharmacokinetic plasma analysis at the following times relative to the end of the dose administration time: Day 1 (pre-dose, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 8 (pre-dose, 8 hours, and 24 hours), Day 15 (pre-dose, 8 hours, and 24 hours), and Day 22 (pre-dose, 30 minutes, 1 hour, 2 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours). (2) A total of six blood samples were collected at the following times relative to the end of the drug administration period and analyzed for protein binding: (a) Total IgA, IgE, and IgM: Day 1 (pre-drug administration) and Day 25; (b) Total IgG (including subclasses IgG1, IgG2, IgG3, and IgG4) was assayed on Day 1 (pre-drug administration, 4 hours, 8 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 8 (pre-drug administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 15 (pre-drug administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 22 (pre-drug administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), and Days 36, 50, and 64. (4) Assays were performed on samples on day -1, day 1 (8 hours and 24 hours), day 5, day 8 (8 hours and 24 hours), day 12, day 15 (8 hours and 24 hours), day 19, day 22 (8 hours and 24 hours), day 26, day 36, day 50, and day 64. (5) Standard biochemical assays, screening day HbA1c, hematology, and urinalysis tests were performed on day -1, day 2, day 4, day 7, day 9, day 11, day 14, day 16, day 18, day 21, day 23, day 26, day 36, day 50, and day 64.

[0299] For the assay in Part 2b of this embodiment (multiple dose escalations), 1) a total of 32 blood samples were collected for pharmacokinetic plasma analysis at the time of dose completion on day 1 (pre-administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, and 48 hours), day 5 (pre-administration and 24 hours), day 8 (pre-administration, 8 hours, and 24 hours), day 15 (pre-administration, 8 hours, and 24 hours), and day 22 (pre-administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours). (2) A total of 6 blood samples were collected and analyzed for protein binding on day 1 (1 hour, 4 hours, and 12 hours) and day 22 (1 hour, 4 hours, and 12 hours). (3) Blood samples for the following pharmacodynamic tests were collected at the following time points: (a) Total IgA, IgE, and IgM. Screening was performed on day 1 (pre-administration) and day 25. (b) Total IgG (including subclasses IgG1, IgG2, IgG3, and IgG4). Screening was performed on day 1, day 1 (pre-administration, 24 hours, 48 ​​hours, 72 hours, 96 hours, 120 hours, and 144 hours), day 8 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), day 15 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), day 22 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), as well as on day 36, day 50, and day 64. (4) Standard biochemistry (HbA1c on the screening day), hematology, and urinalysis tests were performed on the screening day, and on days 1, 2, 4, 5, 7, 9, 11, 14, 16, 18, 21, 23, 26, 36, 50, and 64.

[0300] Preclinical study – Pharmacokinetics / toxicokinetics of intravenous or subcutaneous FCIII-GN3 administration in rats. As part of a non-GLP toxicity study, the toxicokinetics of FCIII-GN3 were determined in Sprague Dawley rats by intravenous infusion over approximately 60 minutes, once daily for 7 consecutive days, at doses of 250 or 500 mg / kg / day. Post-infusion exposure increased only slightly less proportionally between the 250 mg / kg and 500 mg / kg dose levels. There was no evidence of accumulation.

[0301] As part of a non-GLP toxicity study, the toxicological pharmacokinetics of FCIII-GN3 were determined in Sprague Dawley rats administered 75 mg / kg / day, 250 mg / kg / day, or 400 mg / kg / day once daily for 14 consecutive days via intravenous bolus (75 mg / kg / day and 250 mg / kg / day groups) or intravenous slow injection (400 mg / kg / day group). Toxicological pharmacokinetics were also measured in Sprague Dawley rats administered 250 mg / kg / day subcutaneously daily for 14 consecutive days. After intravenous administration, systemic FCIII-GN3 exposure (AUClast) generally increased proportionally to the dose from 75 mg / kg / day to 400 mg / kg / day. No FCIII-GN3 accumulation was observed after multiple intravenous or subcutaneous administrations.

[0302] In toxicity studies, the pharmacokinetics of FCIII-GN3 were determined in Sprague Dawley rats administered 50, 100, or 150 mg / kg / day once daily by intravenous bolus (50 and 100 mg / kg / day) or intravenous slow injection (150 mg / kg / day for 28 consecutive days). Systemic FCIII-GN3 exposure (C0 and AUClast) generally increased dose-proportionally from 50 mg / kg / day to 150 mg / kg / day in both sexes. No accumulation was observed after multiple intravenous administrations in rats. No sex-related differences were observed. At a NOAEL of 150 mg / kg / dose, mean C0 and AUClast values ​​were 651,000 ng / mL and 359,000 ng·h / mL (sex combined) after 28 days.

[0303] As part of a 13-week toxicity study, the toxicological kinetics of FCIII-GN3 were determined in Sprague Dawley rats administered subcutaneously by vehicle or at doses of 150, 250, or 500 mg / kg twice weekly for 13 weeks. Exposure to FCIII-GN3 did not differ significantly between sexes (<2-fold). Exposure to FCIII-GN3 did not appear to change after repeated administrations. There was no accumulation of FCIII-GN3. The systemic NOAEL was defined as 500 mg / kg, resulting in sex-combined Cmax and AUC0-24 hour values ​​of 49,000 ng / mL and 623,000 ng·h / mL, respectively, after 13 weeks.

[0304] Pharmacokinetics / toxicokinetics of intravenous / subcutaneous FCIII-GN3 administration in cynomolgus monkeys. FCIII-GN3 toxicokinetics were determined in cynomolgus monkeys administered 1 mg / kg, 3 mg / kg, and 10 mg / kg of FCIII-GN3 via intravenous bolus once weekly on days 1, 8, and 15 for three consecutive weeks. Systemic FCIII-GN3 exposure (AUClast) generally increased more than dose-proportionally from 1 mg / kg / week to 10 mg / kg / week in both sexes. Systemic exposure on day 15 was similar to that on day 1 for 1 and 3 mg / kg / week, and higher for 10 mg / kg / week. No sex-related differences were observed.

[0305] The toxicological kinetics of FCIII-GN3 were determined in cynomolgus monkeys administered 75 mg / kg, 250 mg / kg, 375 mg / kg, and 500 mg / kg of FCIII-GN3 once on days 1, 8, and 15 via slow intravenous bolus. Systemic exposure (Cmax and AUClast) to FCIII-GN3 did not increase proportionally across the dose range of 75 mg / kg to 300 mg / kg, and exposure was similar at 375 mg / kg and 500 mg / kg. No differences related to FCIII-GN3 accumulation or sex were observed.

[0306] The toxicological pharmacokinetics of FCIII-GN3 were also determined in cynomolgus monkeys administered FCIII-GN3 slow intravenous bolus injections of 75 mg / kg, 250 mg / kg, or 500 mg / kg twice weekly on days 1, 4, 8, 11, 15, 18, 22, 25, and 29. The systemic exposure AUC (0-24) of FCIII-GN3 did not increase proportionally across the 75-500 mg / kg dose range, and no sex-related differences were observed. In NOAELs at 1000 mg / kg / week (500 mg / kg twice weekly), the mean C0 and AUClast values ​​were 5,360,000 ng / mL and 26,200,000 ng·h / mL / week, respectively, on day 1 (adjusted for sex). Systemic exposure (C0 and AUClast) decreased after repeated administration of FCIII-GN3 (accumulation ratios ranged from 0.318 to 0.555).

[0307] As part of a 13-week toxicity study (CRL 20457823), the toxicological kinetics of FCIII-GN3 were determined in cynomolgus monkeys administered doses of 250, 500, or 1000 mg / kg of FCIII-GN3 by subcutaneous injection twice weekly. Individual plasma concentration-time profiles, Cmax, and AUC values ​​were similar between males and females on days 1 and 89. Cmax and AUC 0-24 increased proportionally with increasing doses of FCIII-GN3, while individual Cmax and AUC 0-24 values ​​overlapped between doses on both days 1 and 89.

[0308] FCIII-GN3 administration decreased after repeated systemic exposures (Cmax and AUClast). The accumulation ratio ranged from 0.473 to 0.676. NOAEL was defined as 2000 mg / kg / week (1000 mg / kg twice weekly). The mean Cmax and AUC0-72 values ​​for each sex combination were 900,000 ng / ml and 20,000,000 ng·h / ml, respectively, on day 1.

[0309] Nonclinical toxicology studies demonstrated an acceptable safety profile that supports the evaluation of FCIII-GN3 in clinical studies in humans.

[0310] Crynomolgus monkeys are the most relevant toxicological species for FCIII-GN3 risk assessment. FCIII-GN3 binds to IgG with high affinity and reduces circulating IgG in cynomolgus monkeys, similar to how it does in humans.

[0311] Based on comparable protein binding and hepatic metabolism, it yields similar pharmacokinetics in humans. The NOAEL dose in cynomolgus monkeys was the highest dose tested (1000 mg / kg twice weekly [2000 mg / kg / week] for 3 months). The day 1 AUC and Cmax values ​​associated with this dose were 1.45-fold and 2.0-fold, respectively, compared to the highest predicted human AUC and Cmax associated with the 2000 mg dose.

[0312] In a four-week central study of cynomolgus monkeys, intravenous administration of FCIII-GN3 twice weekly was well tolerated at dose levels of 75 mg / kg, 250 mg / kg, and 500 mg / kg (150 mg / kg, 500 mg / kg, and 1000 mg / kg / week). In all treated males and females, serum IgG levels decreased 2-4 times 72 hours after the first dose compared to baseline levels and remained decreased until the end of the treatment period. This decrease was considered to be a pharmacological effect of FCIII-GN3. The no-obligation allowance (NOAEL) was considered to be 500 mg / kg twice weekly (1000 mg / kg / week).

[0313] In a 13-week study, FCIII-GN3 was administered to cynomolgus monkeys by subcutaneous injection at doses of 250 mg / kg, 500 mg / kg, or 1000 mg / kg twice weekly (500 mg / kg / week, 1000 mg / kg / week, and 2000 mg / kg / week). FCIII-GN3-related changes in immunoglobulins were recorded for IgG in animals administered doses of 250 mg / kg / dose or higher, starting from day 1 (48 hours post-administration) to the final post-administration point (day 89). This effect is related to the pharmacological activity of FCIII-GN3. The NOAEL in this example was 2000 mg / kg / week (1000 mg / kg twice weekly), which was the highest dose tested.

[0314] Administration of FCIII-GN3 at a dose of 500 mg / kg was well tolerated in rats when delivered via slow 60-minute intravenous infusion daily for 7 days. Furthermore, FCIII-GN3 was administered in single-dose studies at 750, 1500, and 2000 mg / kg via slow 60-minute intravenous infusion. FCIII-GN3-related clinical observations were recorded immediately after administration of 2000 mg / kg and included decreased activity, coldness to touch, uncoordinated movement / abnormal gait, and shallow breathing, which fully recovered by day 2. Microscopic findings related to FCIII-GN3 at euthanasia on day 3 were shown in the kidneys, heart, skeletal muscle, and Harderian glands; these results showed recovery on day 8, suggesting reversibility. At 2000 mg / kg, minimal to mild degeneration and necrosis of cardiomyocytes were observed in 3 / 10 males and 3 / 10 females euthanized on day 3; minimal to mild degeneration and necrosis of muscle cells in skeletal muscle were observed in 4 / 10 males and 2 / 10 females; minimal to significant degeneration and necrosis of acinar cells, as well as minimal to moderate mixed cell inflammation in the Harderian glands, were observed in 6 / 10 males and 1 / 10 females. Regeneration was observed in the heart, skeletal muscle, and Harderian glands on day 8 after euthanasia, indicating recovery. Minimal tubular vacuole formation, not harmful to the kidneys, was observed in both males and females at 2000 mg / kg. NOAEL was 750 mg / kg, with a mean AUC of 706,000 ng·h / mL, mean Cmax of 700,000 ng / mL.

[0315] In a 4-week central study of rats, minimal vacuolar formation in the renal tubular epithelium was observed in both males and females (FCIII-GN3 > 50 mg / kg / day); 31% of FCIII-GN3 was excreted in the urine of rats at a dose of 150 mg / kg / day, compared to less than 1% excreted in cynomolgus monkeys or humans at clinically relevant concentrations. Renal histology was normal in cynomolgus monkeys. The NOAEL in the 4-week central study was 150 mg / kg / day, which was the highest dose administered in this study.

[0316] In a 13-week study, FCIII-GN3 was administered to rats twice weekly by subcutaneous injection at doses of 150, 250, and 500 mg / kg / dose. Clinical signs and microscopic results at FCIII-GN3-related local injection sites were recorded at doses of 150 mg / kg / dose and above, which included clinically observed combinations of swelling, dry lesions with or without discharge, crusting, peeling, bruising, thickening, and / or discolored skin, as well as microscopic results of skin and subcutaneous inflammation with mixed cell inflammation of muscle fibers, degeneration / necrosis, severe ulceration / erosion, minimal to prominent crusting, epidermal hyperplasia / hyperkeratosis, and prominent dermatofibrosis. The systemic NOAEL was considered to be at the highest dose tested, 500 mg / kg / dose, based on the absence of systemic adverse outcomes.

[0317] FCIII-GN3 was not cytotoxic, phototoxic, genotoxic, or chromosomal aberration-inducing.

[0318] Standard batteries for in vitro and in vivo toxicology studies support multiple subcutaneous administrations of FCIII-GN3 at formulation concentrations up to 250 mg / mL over 4 weeks, with doses up to 2000 mg per week.

[0319] Summary of Clinical Trials (FCIII-GN3 is currently in clinical trials and is not approved for any therapeutic use. FCIII-GN3 was evaluated in a single-dose escalating dose SAD trial conducted in the subjects.) Subjects received a single dose of FCIII-GN3 (6 subjects received intravenous doses of 50 mg, 125 mg, 250 mg, and 500 mg, respectively, and a subcutaneous dose of 500 mg), while a total of 10 subjects received placebo.

[0320] Cumulative preliminary safety data from the first five cohorts of the ongoing single-dose escalation study indicate that single doses of FCIII-GN3 ranging from 50 mg to 500 mg via intravenous infusion over 30 minutes or a single dose of 500 mg administered subcutaneously were well tolerated. No serious adverse events were reported.

[0321] The doses from the intravenous 500 mg cohort in the single dose escalation study for geometric mean Cmax and AUCinf were approximately 139 μg / mL and 2,193 μg·h / mL, respectively. The doses from the subcutaneous 500 mg cohort in the single dose escalation study for geometric mean Cmax and AUCinf were approximately 115.6 μg / mL and 3172 μg·h / mL, respectively. Tmax was reached 6–12 hours after subcutaneous injection. It exhibited a short half-life (<8 hours) and rapid FCIII-GN3 clearance (99% eliminated in ~72 hours).

[0322] The safety margin was calculated as the ratio of the most tolerable first dose exposure in cynomolgus monkeys, a species associated with human safety, to the simulated weekly exposure derived from a human model.

[0323] Pharmacokinetic / pharmacodynamic modeling based on cynomolgus monkey data predicts that subcutaneous administration of 500 mg of FCIII-GN3 will result in an average decrease of approximately 32% in baseline total IgG after administration #1. The predicted average maximum percentage decrease in total IgG after the fourth and final administration (day 22) of the study drug is approximately 64%. The average IgG decrease is predicted to increase with increasing dose and multiple administrations; the net decrease is predicted to be maximum after the first three administrations; and the decrease in IgG approaches a steady state.

[0324] Across all subsequent multi-dose cohorts, the total weekly dose of FCIII-GN3 did not exceed that previously evaluated as a single dose in humans, and the predicted exposure associated with repeated FCIII-GN3 administration did not exceed the NOAEL weekly exposure established from preclinical studies.

[0325] General Safety Considerations: FCIII-GN3 is a next-generation immunomodulator designed to offer potential benefits over FcRn-targeting agents (which also reduce IgG levels). Firstly, FCIII-GN3 is designed to selectively and transiently target IgG1, IgG2, and IgG4 while preserving subclass IgG3. IgG3 preservation by FCIII-GN3 is expected to increase the robustness of host defense against a given degree of IgG reduction and may benefit those requiring long-term treatment. Secondly, FCIII-GN3 is a small molecule that provides an easily administered clinical formulation compared to provider-administered subcutaneous formulations of FcRn. Thirdly, FCIII-GN3 is not expected to exhibit the immunogenicity seen in biologics. Fourthly, FCIII-GN3 is expected to have a short half-life in humans, offering the benefit of co-administration with standard therapeutic Fc-containing biologics. Finally, FCIII-GN3 is not expected to have effects on albumin, cholesterol, or triglycerides related to the mechanism of action of FcRn.

[0326] Antibodies or antibody fragments that target the neonatal Fc receptor (FcRn) and subsequently reduce IgG are currently being developed to treat multiple immune-related disorders. Importantly, FcRn inhibitor studies have shown no increase in infection, and the reduction in IgG in subjects was up to 85%, lasting for approximately 3 months. (Ulrichts et al., The Journal of Clinical Investigation, 128(10), 4372-4386 (2018); Ling et al., Clin. Pharmacol., 105(4), 1031-1039 (2019); Kiessling et al., Science Translational Medicine, 9(414) (2017).)

[0327] Evidence based on cumulative nonclinical toxicology, previous studies with FcRn inhibitors, and safety data from ongoing single-dose escalation studies supports multiple subcutaneous administrations of FCIII-GN3 at a maximum formulation concentration of 250 mg / mL over 4 weeks, with a maximum dose of 2000 mg / week.

[0328] FCIII-GN3 was administered subcutaneously to the abdomen. The maximum dose volume administered was 2 mL per syringe per quadrant of the abdomen. Several syringes were used for dose escalation levels exceeding 500 mg or for the equivalent placebo.

[0329] The formula used to calculate the glomerular filtration rate (GFL) using the 2021 CKD-EPI is as follows: Estimated glomerular filtration rate = 142 x min(Scr / κ,1)α x max(Scr / κ,1)-1.2 x 0.9938 age x 1.012, for females. Scr is serum creatinine (mg / dL), κ is 0.7 for females and 0.9 for males, α = -0.241 (females) or -0.302 (males), min represents the minimum value of Scr / κ or 1.0, and max represents the maximum value of Scr / κ or 1.0.

[0330] The parameters for the pharmacokinetic FCIII-GN3 plasma concentration were calculated.

[0331] For days 1 and 22 of Part 1 and Part 2, the following pharmacokinetic parameters were calculated: AUC0-96h: Area under the concentration-time curve from time 0 to time 96h. AUC0-96h / dose: Dose-normalized AUC0-96h. AUCinf: Area under concentration extrapolated from time 0 to infinity. AUCinf / dose: Dose-normalized AUCinf. Cl / F: Apparent total clearance. Cmax: Maximum observed concentration. Cmax / dose: Dose-normalized Cmax. T1 / 2: Apparent primary end elimination half-life. Tmax: Time at which maximum concentration is observed. Vd / F: Apparent volume of distribution.

[0332] Other pharmacokinetic parameters in Part 2 were calculated based on day 1 and day 22. For pharmacokinetics, RAAUC 0-96 hours was used, and the observed accumulation ratio was based on AUC 0-96 hours for day 22 / day 1.

[0333] For Part 2b, the observed accumulation rate was calculated based on RAAUC0-72 hours: AUC0-72 hours on day 22 / day 1. For RACmax, the observed accumulation ratio was based on Cmax calculated as Cmax on day 22 / Cmax on day 1. The area under the concentration-time curve (AUC0-72 hours) from the start time to 72 hours was calculated and the dose was normalized.

[0334] Pharmacokinetic statistical analysis and pharmacokinetic parameter determination were performed using Phoenix® and WinNonlin®. Individual and mean plasma concentration-versus-time curves are presented for both linear and semi-logarithmic scales. Descriptive statistics of plasma concentration-versus-time, and pharmacokinetic parameters, are presented day by day where appropriate. To assess dose-proportionality, a power model approach was used for AUC0-96, AUCinf, and Cmax for Parts 1 and 2.

[0335] (Subcutaneous FCIII-GN3 administration achieved a deep and sustained reduction in IgG, with a rebound in IgG levels expected after drug elimination (see Figures 9-12)). Subcutaneous FCIII-GN3 injection at 2000 mg achieved a mean maximum reduction of 81% of total IgG by day 18 (3 doses). Subcutaneous FCIII-GN3 administration achieved a deep, rapid, and adjustable reduction of IgG, tailored to the specific needs of IgG-related disease. These results were comparable to the IgG reduction results achieved at week 4 using FcRn-targeted therapies in ADAPT-SC. Howard et al. Neurotherapeutics (2024). In Figures 11-12, black circles represent the median maximum total IgG% change from baseline for that week, and bars represent the 25th and 75th percentiles.

[0336] Subcutaneous administration of FCIII-GN3 (2000 mg) offers a new potential paradigm for the management of acute disease, reducing IgG as rapidly and deeply as plasmapheresis. Two doses of FCIII-GN3 reduce IgG as deeply and rapidly as these invasive methods, including plasmapheresis.

[0337] Subcutaneous administration of FCIII-GN3 targets the underlying causes of a wide range of autoimmune diseases to treat and prevent multi-organ complications. The IgG degrader eliminates the autoantibodies that cause Graves' disease. Graves' disease is a classic antibody-mediated disease that has been treated with conventional therapies that have not addressed the underlying antibodies. This IgG degrader eliminates IgG, thereby eliminating the disease drivers of Graves' disease, thyroid eye disease, and thyroid dermatopathy. Evaluation of single and multiple doses of an optimized subcutaneous formulation of FCIII-GN3 in a randomized, open-label, placebo-controlled trial.

[0338] FCIII-GN3 was administered as a subcutaneous dose. FCIII-GN3 is supplied at 250 mg / mL and is a clear, colorless solution that is essentially free of visible particulate matter. Each vial contains an extractable volume of 3 mL (750 mg). The corresponding placebo for FCIII-GN3 is 0.9% physiological saline, a homogeneous, clear, colorless liquid.

[0339] The primary objective of the single-dose and multi-dose studies was to evaluate the safety and tolerability of FCIII-GN3 after single and multi-dose subcutaneous administration. A secondary objective of the single-dose and multi-dose studies was to characterize the pharmacokinetic profile of FCIII-GN3 after single and multi-dose subcutaneous administration. Other objectives included: (1) characterizing the pharmacodynamic effects of FCIII-GN3 after single and multi-dose subcutaneous administration; (2) characterizing the binding of FCIII-GN3 to plasma proteins; (3) evaluating the immunogenicity of FCIII-GN3; (4) evaluating the effect of FCIII-GN3 on electrocardiogram (ECG) parameters after single-dose administration; and (5) characterizing the urinary pharmacokinetics of a single dose of FCIII-GN3.

[0340] For single-dose and multi-dose studies, the primary endpoint is to assess safety and tolerability by reporting the frequency of specific subjects with severe adverse events and grade 3-4 (CTCAE / DAIDS) abnormal laboratory findings occurring during treatment. For single-dose and multi-dose studies, secondary endpoints are: (1) Day 1 of Part 1 and Part 2: AUC0-72 hours (Part 2b), AUC0-96 hours (Part 1 and Part 2a), AUCinf, Cmax, Tmax, T1 / 2, CL / F, and Vd / F. (2) Day 22 of Part 2: AUC0-72 hours (Part 2b), AUC0-96 hours, AUCinf, Cmax, Tmax, T1 / 2, RAAUC0-96 hours, RACmax, CL / F, and Vd / F.

[0341] This example describes randomized, open-label, placebo-controlled, single-dose and multi-dose studies. This example consists of two parts: Part 1 includes three single-dose cohorts, and Part 2 includes four multi-dose cohorts.

[0342] Part 1 single-dose escalation. A time-staggered dosing schedule was used for dosing in each single-dose escalation cohort. The schedule included two monitored subjects who received the first dose (one active drug, one placebo). The remaining six subjects (five active drugs, one placebo) were administered after reviewing available safety and tolerability data from the two monitored subjects for at least 24 hours.

[0343] Part 2 consisted of multiple dose escalation cohorts, each containing approximately 10 subjects (8 receiving the active drug and 2 receiving placebo). The planned dose range across Part 1 and Part 2 cohorts was 500–2000 mg of FCIII-GN3 or placebo. Subcutaneous injections were administered into the abdomen.

[0344] Safety and Tolerability: The safety and tolerability of FCIII-GN3 were assessed by reporting the frequency of unique subjects with severe adverse events and grade 3-4 (CTCAE / DAIDS) laboratory abnormalities. Adverse events were coded using the current version of the Regulatory Activity Medical Dictionary (MedDRA). Laboratory study results were graded according to numerical laboratory study criteria in the latest version of CTCAE, where criteria for the study were available, otherwise according to descriptive terminology in the latest version of the DAIDS table for grading the severity of adult and pediatric AEs.

[0345] Pharmacokinetics. Plasma concentrations and pharmacokinetic parameters were described using summary statistics. A power model approach was used to assess dose-proportionality for AUC0-96, AUCinf, and Cmax for day 22 of Part 1 and Part 2.

[0346] A total of 15 blood samples were collected for pharmacokinetic analysis at the end of the injection administration time on day 1: pre-administration, 20 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, 96 hours, and 168 hours (day 8).

[0347] Plasma samples were collected and analyzed for protein binding 6 hours and 48 hours after the end of the injection time following administration on day 1.

[0348] Pharmacodynamic blood samples for the following tests were collected at the following times: (1) Total IgA, IgE, and IgM on Day 1, before administration on Day 1, 96 hours, and Day 36. (2) Total IgG (including subclasses 1, 2, 3, and 4): Screening day, Day 1, Day 1 (before administration, 4 hours, 8 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours), as well as Day 8, Day 15, Day 22, Day 29, and Day 36. (3) Circulating immune complex C3: Day 1 (before administration, 4 hours, 24 hours, 48 ​​hours, and 72 hours), as well as Day 8, Day 22, and Day 29. (4) Circulating immune complex C1q on Day 1 (before administration, 4 hours, 24 hours, 48 ​​hours, and 72 hours), as well as Day 8, Day 22, and Day 29. (5) Cytokines (including IL-6, TNF-α, IFN-γ, and IL-1-β) were assayed from samples obtained on day 1 (before administration and 4 hours later), day 2, and day 5.

[0349] Pharmacokinetic urine samples were collected on day 1 for pharmacokinetic analysis at the following intervals: 0–4 hours, 4–8 hours, 8–12 hours, 12–24 hours, 24–48 hours, 48–72 hours, and 72–96 hours post-administration.

[0350] 12-lead safety electrocardiograms (ECGs) were collected on day 1, before administration on day 1, 1.5 hours, 3 hours, 6 hours, and 12 hours after administration, as well as on days 2, 3, and 4.

[0351] Standard biochemistry (HbA1c on the screening day), hematology, and urinalysis tests will be performed on days 1, 2, 4, 5, 8, 15, 22, 29, and 36.

[0352] A total of 32 blood samples were collected for pharmacokinetic plasma analysis at the end of drug administration on day 1 (before administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours), day 8 (before administration, 8 hours, and 24 hours), day 15 (before administration, 8 hours, and 24 hours), and day 22 (before administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours).

[0353] A total of six blood samples were collected and analyzed for protein binding on day 1 (1 hour, 4 hours, and 12 hours) and day 22 (1 hour, 4 hours, and 12 hours).

[0354] Pharmacodynamic blood samples for the following tests were collected at the following time points: (1) Total IgA, IgE, and IgM: Day 1 (pre-administration) and Day 25. (2) Total IgG (including subclasses IgG1, IgG2, IgG3, and IgG4): Day 1, Day 1 (pre-administration, 4 hours, 8 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 8 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 15 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 22 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), as well as Day 36, Day 50, and Day 64.

[0355] 12-lead safety electrocardiograms were collected on day 1, day 1 (pre-administration, 2, 4, 8, 12, and 24 hours), day 8 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 15 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 22 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), and day 26.

[0356] Standard biochemistry (HbA1c on the screening day), hematology, and urinalysis tests were performed on days 1, 2, 4, 7, 9, 11, 14, 16, 18, 21, 23, 26, 36, 50, and 64.

[0357] Thirty-two blood samples were collected for pharmacokinetic plasma analysis at the end of the dose-infusion time on day 1 (before administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours), day 5 (before administration and 24 hours), day 8 (before administration, 8 hours, and 24 hours), day 15 (before administration, 8 hours, and 24 hours), and day 22 (before administration, 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 8 hours, 10 hours, 12 hours, 24 hours, 48 ​​hours, 72 hours, and 96 hours).

[0358] A total of six blood samples were collected and analyzed for protein binding on day 1 (1 hour, 4 hours, and 12 hours) and day 22 (1 hour, 4 hours, and 12 hours).

[0359] Pharmacodynamic blood samples were collected for the following tests and (1) assayed for total IgA, IgE, and IgM: Day 1 (pre-administration) and Day 25. (2) Total IgG (including subclasses IgG1, IgG2, IgG3, and IgG4): Day 1, Day 1 (pre-administration, 24 hours, 48 ​​hours, 72 hours, 96 hours, 120 hours, and 144 hours), Day 8 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 15 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), Day 22 (pre-administration, 24 hours, 48 ​​hours, 72 hours, and 96 hours), as well as Day 36, Day 50, and Day 64.

[0360] 12-lead safety electrocardiograms were collected on day 1, day 1 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 4 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 8 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 15 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), day 22 (pre-administration, 2 hours, 4 hours, 8 hours, 12 hours, and 24 hours), and day 26.

[0361] Standard biochemical assays, hematological tests, and urinalysis tests, including HbA1c, were performed on days 1, 2, 4, 5, 7, 9, 11, 14, 16, 18, 21, 23, 26, 36, 50, and 64, starting from the screening day.

[0362] Approximately 3-10% of the population suffers from autoimmune diseases, many of which are associated with pathogenic IgG autoantibodies, making IgG targeting an essential strategy for treating these disorders. Newly emerging IgG-targeted therapies, including neonatal Fc receptor antagonists such as Vyvgart, efgartigimod alfa-fcab, and Rystiggo, rozanolixizumab-noli, reduce total IgG but are limited by suboptimal pharmacological and pharmacodynamic effects, cannot be co-administered with monoclonal antibodies, have potential mechanism-based effects on cholesterol and albumin, and have relatively long half-lives that hinder IgG recovery until Fc fragments are removed.

[0363] Non-clinical study summary: In vitro and in vivo non-clinical studies demonstrated the binding of FCIII-GN3 to ASGPR1 CRD and human IgG subclasses, as well as the concentration-dependent FCIII-GN3-mediated uptake of IgG into HepG2 cells and human primary hepatocytes. Safety pharmacological evaluations showed no dose-dependent adverse effects of FCIII-GN3 on the central nervous system, respiratory system, or cardiovascular system.

[0364] The potential effects of FCIII-GN3 on the central nervous system, respiratory system, and cardiovascular system were evaluated in regulatory and ICH guideline-compliant studies. In cynomolgus monkeys, FCIII-GN3 at doses up to 500 mg / kg did not yield results in functional observational battery evaluation electrocardiogram, hemodynamic, or respiratory function parameters. In hERG assays, the median inhibitory concentration (IC50) was 2191.1 μM. These results do not indicate a significant human risk.

[0365] The apparent permeability of FCIII-GN3, including its pharmacokinetics and product metabolism / absorption, was investigated in vitro by evaluating concentration-dependent bidirectional transport using an MDCKII cell monolayer. 0.5 μM or 5 μM FCIII-GN3 showed low permeability in MDCKII-BCRP and Abbcb1KO MDCKII-MDR cells, because the permeability values ​​were lower than those of the relevant controls.

[0366] Following intravenous administration of absorbed se after a single irradiation, FCIII-GN3 plasma clearance was moderate in mice (42.3 mL / min / kg; hepatic flow 90 mL / min / kg), low in rats (6.39 mL / min / kg; hepatic blood flow 77 mL / min / kg), and low in rabbits (range of 0.24–0.97 mL / min / kg; hepatic blood flow 70.8 mL / min / kg). Vss was high in mice (137 L / kg), low in rats (0.332 L / kg), and low in rabbits (range of 0.03–0.11 L / kg). T1 / 2 was 234 hours in mice, 2.52–10.6 hours in rats, 3.70–9.18 hours in rabbits, and 16.1–88.3 hours in monkeys.

[0367] In a single-dose high-dose intravenous infusion study, rats were administered FCIII-GN3 at doses of 750 mg / kg, 1500 mg / kg, or 2000 mg / kg via 60-minute intravenous infusion. Systemic exposure to FCIII-GN3 was similar between sexes. Individual plasma concentration-time profiles, Cmax, and AUClast values ​​were similar between males and females. Sex-combined Cmax and AUClast values ​​for FCIII-GN3 increased with increasing dose from 750 to 2000 mg / kg. The increase in systemic exposure was approximately dose-proportional. NOAEL was defined as 750 mg / kg, resulting in Cmax and AUC0-25 hour values ​​of 700,000 ng / mL and 706,000 ng·hr / mL, respectively (sex-combined).

[0368] In rats, FCIII-GN3 exposure based on C0 and AUClast increased proportionally with dose, and no sex-related differences were observed. In cynomolgus monkeys, exposure based on Cmax did not increase proportionally with dose, and exposure based on AUClast did not consistently increase with dose.

[0369] Absorption and repeated-dose TK / pharmacokinetic studies were conducted in Sprague Dawley rats and cynomolgus monkeys.

[0370] Pharmacokinetics / TK of FCIII-GN3 administered intravenously / subcutaneously in rats

[0371] As part of a non-GLP toxicity study, the TK of FCIII-GN3 was determined in Sprague Dawley rats by intravenous infusion over approximately 60 minutes, once daily for 7 consecutive days, at doses of 250 mg / kg / day or 500 mg / kg / day. Post-infusion exposure increased slightly less proportionally than dose-proportional between the 250 mg / kg and 500 mg / kg dose levels. There was no evidence of accumulation.

[0372] As part of a non-GLP toxicity study, the total kinetic energy (TK) of FCIII-GN3 was determined in Sprague Dawley rats administered 75, 250, or 400 mg / kg / day once daily for 14 consecutive days by intravenous bolus (75 and 400 mg / kg / day groups) or intravenous slow injection (250 mg / kg / day group). TK was also measured in Sprague Dawley rats administered 250 mg / kg / day subcutaneously daily for 14 consecutive days. After intravenous administration, systemic exposure (AUClast) to FCIII-GN3 generally increased dose-proportionally from 75 to 400 mg / kg / day in both sexes. No accumulation of FCIII-GN3 was observed after multiple intravenous or subcutaneous administrations.

[0373] In toxicity studies, the TK of FCIII-GN3 was determined in Sprague Dawley rats administered intravenously by bolus (50 and 100 mg / kg / day) or slow intravenous injection (150 mg / kg / day) once daily for 28 consecutive days at doses of 50 mg / kg / day, 100 mg / kg / day, or 150 mg / kg / day. Systemic exposure (C0 and AUClast) to FCIII-GN3 generally increased proportionally to the dose from 50 to 150 mg / kg / day in both sexes. No accumulation was observed after multiple intravenous administrations in rats, and no sex-related differences were observed. At a 150 mg / kg / dose NOAEL, the mean C0 and AUClast values ​​were 651,000 ng / mL and 359,000 ng·h / mL (sex combined) after 28 days.

[0374] As part of a 13-week toxicity study, the TK of FCIII-GN3 was determined in Sprague Dawley rats administered subcutaneously by vehicle or at doses of 150, 250, or 500 mg / kg twice weekly for 13 weeks. Exposure to FCIII-GN3 did not differ significantly between sexes (<2x) and did not appear to change after repeated administrations of FCIII-GN3. There was no accumulation of FCIII-GN3. The systemic NOAEL, defined as 500 mg / kg, resulted in combinations of Cmax and AUC0-24 hour values ​​of 49,000 ng / mL and 623,000 ng·h / mL, respectively, after 13 weeks.

[0375] Pharmacokinetics / TK of FCIII-GN3 after intravenous / subcutaneous administration in monkeys. As part of a non-GLP toxicity study, the TK of FCIII-GN3 was determined in cynomolgus monkeys administered 1 mg / kg, 3 mg / kg, and 10 mg / kg of FCIII-GN3 by intravenous bolus once weekly on days 1, 8, and 15 for three consecutive weeks. Systemic exposure (AUClast) of FCIII-GN3 generally increased more significantly than dose-proportionally in both sexes from 1 mg / kg / week to 10 mg / kg / week. Systemic exposure on day 15 was similar to that on day 1 for 1 mg / kg / week and 3 mg / kg / week, and higher for 10 mg / kg / week. Overall, no sex-related differences were observed.

[0376] As part of a non-GLP toxicity study, the time factor (TK) of FCIII-GN3 was determined in cynomolgus monkeys administered 75 mg / kg, 250 mg / kg, 375 mg / kg, and 500 mg / kg of FCIII-GN3 once on days 1, 8, and 15 via slow intravenous bolus. Systemic exposure (Cmax and AUClast) to FCIII-GN3 increased proportionally with the dose range of 75–300 mg / kg, with similar exposures at 375 and 500 mg / kg. No accumulation or sex-related differences in FCIII-GN3 were observed.

[0377] As part of the toxicity study, the TK of FCIII-GN3 was determined in cynomolgus monkeys administered FCIII-GN3 slow intravenous bolus injections of 75, 250, or 500 mg / kg twice weekly on days 1, 4, 8, 11, 15, 18, 22, 25, and 29. Systemic exposure to FCIII-GN3 (AUC0-24) did not increase proportionally with the dose across the 75–500 mg / kg dose range, and no sex-related differences were observed. In the NOAEL of 1000 mg / kg / week (500 mg / kg administered twice weekly), the mean C0 and AUClast values ​​were 5,360,000 ng / mL and 26,200,000 ng·h / mL / week, respectively, on day 1 (adjusted for sex). Systemic exposure (C0 and AUClast) decreased after repeated administration of FCIII-GN3 (accumulation ratios ranged from 0.318 to 0.555).

[0378] As part of a 13-week toxicity study (CRL 20457823), the time factor (TK) of FCIII-GN3 was determined in cynomolgus monkeys administered FCIII-GN3 at doses of 250, 500, or 1000 mg / kg by subcutaneous injection twice weekly. Individual plasma concentration-time profiles, Cmax, and AUC values ​​were similar between males and females on Day 1 and Day 89. Cmax and AUC0-2 increased proportionally with increasing dose for FCIII-GN3, while individual Cmax and AUC0-24 were overlapping values ​​between doses on both Day 1 and Day 89.

[0379] Systemic exposure (Cmax and AUC0-72) decreased after repeated administration of FCIII-GN3 (accumulation ratios ranged from 0.473 to 0.676). NOAEL was defined as 2000 mg / kg / week (1000 mg / kg twice weekly), and the sex-combined mean Cmax and AUC0-72 values ​​on day 1 were 900,000 ng / ml and 20,000,000 ng·h / ml, respectively.

[0380] The distribution of FCIII-GN3 showed low plasma protein binding in mouse and rat, which was concentration-independent and consistent within the tested range. In rabbit, monkey, and human plasma, FCIII-GN3 showed low concentration-dependent protein binding at 800 μM and very high at 8 and 80 μM. Across rabbit, monkey, and human, the unbound fraction ranged from 0.0% to 1.2% at 8 and 80 μM, and was 31.7% in rabbits, 33.1% in humans, and 56.5% in monkeys at 800 μM. The very high binding observed at 8 and 80 μM in these species is likely due to binding to IgG in plasma saturated at 800 μM.

[0381] FCIII-GN3 showed low binding to the plasma proteins human serum albumin and human α1-acid glycoprotein, which was independent of concentration (unbound fractions ranged from 49.0% to 58.9% for human serum albumin and 47.6% to 77.1% for human α1-acid glycoprotein).

[0382] Metabolism in Monkeys: After repeated intravenous administration of FCIII-GN3 at 375 mg / kg / week (3 monkeys / sex) in monkeys, FCIII-GN3 was the major component in monkey liver homogenate, constituting 55.4% of the drug-related substances. The major metabolites included M1229a, M1229b, and M1114, which arose from a combination of peptide hydrolysis and O-dealkylation of the acetylglucosamine moiety, accounting for 17.9%, 15.6%, and 10.5% of the drug-related substances, respectively. In monkey plasma, FCIII-GN3 was the major circulating component, constituting 99.6% of the drug-related substances. In total, 13 metabolites were identified in monkey plasma, constituting less than 1% of the drug-related substances.

[0383] Qualitative mass spectrometry evaluation of metabolites was performed on urine samples from cynomolgus monkeys after intravenous administration of 500 mg / kg of FCIII-GN3 twice weekly. FCIII-GN3 was the major component in the monkey urine, constituting approximately 75% of the drug-related substances between 0 and 48 hours. In addition to unchanged FCIII-GN3, a total of 15 estimated trace metabolites were detected in the monkey urine, each constituting ≤7.5% of the drug-related substances. The metabolites arose from amide bond hydrolysis (peptides and linkers), O-dealkylation, oxidation, hydration, leucine conjugation, and dimerization of the acetylglucosamine moiety.

[0384] Pharmacokinetic drug interaction studies using mRNA analysis of CYP enzymes revealed no evidence of FCIII-GN3 inducing human CYP1A2, CYP2B6, or CYP3A4 enzymes in cryopreserved hepatocytes, as observed in vitro. These data suggest a low risk of FCIII-GN3 mediating clinically relevant drug interactions via CYP induction at clinical doses.

[0385] FCIII-GN3 at concentrations up to 200 μM did not inhibit CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, or CYP3A4 in pooled HLM. Time- and NADPH-dependent inhibition was assessed by comparing the IC50 shift ratio between 0-minute and 30-minute incubations of the test substance pre-incubation with and without NADPH. The IC50 value was considered to be at the highest concentration tested, >200 μM, indicating a low likelihood of inhibitory CYP-mediated drug interaction.

[0386] (Pharmacokinetic drug interactions. Transporter studies. FCIII-GN3 was not an inhibitor of BCRP, BSEP, or P-gp at clinically relevant concentrations studied in inside-out membrane vesicles derived from HEK293 cells overexpressing human ATP-binding cassette efflux transporter. FCIII-GN3 did not inhibit BSEP-mediated uptake when tested up to a real-world concentration of 85.28 μM (inhibition was <20%). FCIII-GN3 did not inhibit MATE1, MATE2-K, OAT1, OAT3, OAT1B1, OAT1B3, OCT1, or OCT2-mediated uptake at clinically relevant concentrations.)

[0387] FCIII-GN3 was incubated with HEK293 cells overexpressing each of the respective human SLC transporters, either in the presence or absence of the inhibitor. FCIII-GN3 did not appear to be a substrate for the MATE1, MATE2-K, OAT1, OAT3, OATP1B1, OATP1B3, OCT1, and OCT2 transporters at clinically relevant concentrations. There was no significant (>2-fold) increase in uptake or transport activity ratio between cells with and without the inhibitor. Since FCIII-GN3 showed low permeability in a bidirectional permeability assay, its substrate capacity for BCRP and MDR1 was not evaluated.

[0388] Nonclinical toxicology studies demonstrated an acceptable safety profile that supports the evaluation of FCIII-GN3 in clinical studies in humans.

[0389] FCIII-GN3 binds to IgG with high affinity and reduces circulating IgG in cynomolgus monkeys, similar to humans, making cynomolgus monkeys the most relevant toxicological species for risk assessment of FCIII-GN3. FCIII-GN3 does not bind to IgG or reduce IgG in rats. This allows for the use of cynomolgus monkeys in evaluating host defense, and furthermore, similar pharmacokinetics to humans are achieved based on comparable protein binding and hepatic metabolism. The NOAEL dose in cynomolgus monkeys is the highest dose tested (1000 mg / kg / dose twice weekly for 3 months [2000 mg / kg / week]). The day 1 AUC and Cmax values ​​associated with this dose are 1.45-fold and 2.0-fold, respectively, relative to the highest predicted human AUC and Cmax associated with the 2000 mg dose.

[0390] In a four-week central study of cynomolgus monkeys, intravenous administration of FCIII-GN3 twice weekly was well tolerated at dose levels of 75 mg / kg, 250 mg / kg, and 500 mg / kg (150 mg / kg / week, 500 mg / kg / week, and 1000 mg / kg / week). In all treated males and females, serum IgG levels decreased 2-4 times 72 hours after the first day's administration compared to baseline levels and remained decreased until the end of the treatment period. This decrease was considered to be a pharmacological effect of FCIII-GN3. The no-obligation allowance (NOAEL) was considered to be 500 mg / kg twice weekly (1000 mg / kg / week).

[0391] In a 13-week study, FCIII-GN3 was administered to cynomolgus monkeys by subcutaneous injection at doses of 250, 500, or 1000 mg / kg twice weekly (500, 1000, or 2000 mg / kg / week). FCIII-GN3-related changes in immunoglobulins were recorded for IgG in animals receiving doses of 250 mg / kg / dose or higher, starting from day 1 (48 hours post-administration) to the final post-administration point at day 89. This effect is related to the pharmacological activity of FCIII-GN3. The NOAEL (No Observed Adverse Emission Limit) in this study was 2000 mg / kg / week (1000 mg / kg twice weekly), which was the highest dose tested.

[0392] Intravenous bolus administration of FCIII-GN3 in rats did not produce the expected decrease in IgG levels. Intravenous bolus injection (30 seconds to 3 minutes) of FCIII-GN3 at doses of 250 mg / kg or higher in rats resulted in adverse clinical signs and death. Two investigative studies were conducted. Investigative toxicity studies of single doses suggested that the infusion response arose from short intravenous bolus times. Administration of FCIII-GN3 at a dose of 500 mg / kg was well tolerated in rats when delivered via slow 60-minute intravenous infusion daily for 7 days. Furthermore, FCIII-GN3 was administered via slow 60-minute intravenous infusion at doses of 750 mg / kg, 1500 mg / kg, and 2000 mg / kg in single-dose studies. Clinical observations related to FCIII-GN 3 were recorded immediately after administration of 2000 mg / kg and included decreased activity, coldness to touch, uncoordinated movement / abnormal gait, and shallow breathing, which fully recovered by day 2. Microscopic results related to FCIII-GN 3 at euthanasia on day 3 were shown in the kidneys, heart, skeletal muscle, and Harderian glands, and these results showed recovery at day 8, suggesting reversibility. At 2000 mg / kg, harmful minimal to mild degeneration and necrosis of cardiomyocytes were observed in 3 / 10 males and 3 / 10 females euthanized on day 3; minimal to mild degeneration and necrosis of myocytes in skeletal muscle were observed in 4 / 10 males and 2 / 10 females; minimal to significant degeneration and necrosis of acinar cells, as well as minimal to moderate mixed cell inflammation in the Harderian glands, were observed in 6 / 10 males and 1 / 10 females. For these results, regeneration was observed in the heart, skeletal muscle, and Harderian glands at day 8 after euthanasia, indicating recovery. In both males and females, minimal tubular vacuole formation that was not harmful to the kidney was observed at 2000 mg / kg. Considering these factors together, the NOAEL in this study was 750 mg / kg with a mean AUC0-25 hours: 706,000 ng·h / mL and a mean Cmax of 700,000 ng / mL.

[0393] In a 4-week central study of rats, minimal vacuolation of the renal tubular epithelium was observed in both males and females (≥50 mg / kg / day of FCIII-GN3), and was considered non-harmful based on low severity, lack of corresponding clinical signs and clinicopathological changes, and partial recovery. Notably, 31% of FCIII-GN3 was excreted in the urine of rats at a dose of 150 mg / kg / day, compared to <1% in cynomolgus monkeys or humans at clinically relevant concentrations. Renal changes in rats secondary to polyethylene glycol accumulation are likely to indicate renal excretion of FCIII-GN3 and are not considered relevant to human risk assessment. Renal histology was normal in cynomolgus monkeys. The NOAEL for the 4-week central study was 150 mg / kg / day.

[0394] In a 13-week study, FCIII-GN3 was administered to rats twice weekly by subcutaneous injection at doses of 150, 250, and 500 mg / kg / dose. Clinical signs and microscopic results at the local injection site associated with FCIII-GN3 were recorded at doses of 150 mg / kg / dose and above, which included clinically observed combinations of swelling, dry lesions with or without discharge, crusting, peeling, bruising, thickening, and / or discolored skin, as well as microscopic results of skin and subcutaneous inflammation with mixed cell inflammation of muscle fibers, degeneration / necrosis, severe ulceration / erosion, minimal to prominent crusting, epidermal hyperplasia / hyperkeratosis, and prominent dermatofibrosis. Based on these results, a local injection site NOAEL could not be established. The systemic NOAEL was considered to be 500 mg / kg / dose, the highest dose tested, based on the absence of systemic adverse outcomes in any dose group.

[0395] FCIII-GN3 was not cytotoxic, phototoxic, genotoxic, or chromosomal aberration-inducing. Standard batteries for in vitro and in vivo toxicological studies support multiple subcutaneous administrations of FCIII-GN3 over 4 weeks at formulation concentrations up to 250 mg / mL, with doses up to 2000 mg per week.

[0396] In studies of pharmacologically related species (cynomolgus monkeys), administration of FCIII-GN3 reduced IgG by approximately 80% without evidence of infection. In non-pharmacologically related species, as expected, there was no reduction in IgG or evidence of infection in animals administered FCIII-GN3. The risk of infection in humans cannot be ruled out due to the role of IgG in host defense.

[0397] Summary of the clinical trial. FCIII-GN3 was evaluated in a single-dose escalation SAD trial conducted in the target population. 30 subjects received a single dose of FCIII-GN3 (6 received intravenous doses of 50, 125, 250, and 500 mg, and 500 mg subcutaneously, respectively), while a total of 10 subjects received placebo.

[0398] Cumulative preliminary safety data from the first five cohorts of the ongoing study indicate that single doses of FCIII-GN3, ranging from 50 mg to 500 mg via intravenous infusion over 30 minutes or a single dose of 500 mg administered subcutaneously, were well tolerated. No serious adverse events were reported. Most adverse events were mild, resolved spontaneously, and were unrelated to FCIII-GN3. There was no clinical evidence of infusion-related reactions in the four intravenous single-dose escalation cohorts. There was no clinical evidence of adverse skin reactions in the single-dose subcutaneous single-dose escalation cohort. As a component of safety laboratory monitoring, subjects had IgG levels assessed throughout the course of the study, and the a priori suspension rule regarding IgG decline was not met.

[0399] The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of FCIII-GN3 after single-dose and multi-dose subcutaneous administration in a population that supports further clinical development of FCIII-GN3. This study was supported by safety, tolerability, pharmacokinetics, and pharmacodynamics from single-dose escalation studies. Single doses in the range of 50–500 mg have been safely administered to humans.

[0400] For rationale studies of research populations, subjects without associated diseases or medications represent a homogeneous population that allows for appropriate evaluation of the safety, tolerability, pharmacokinetic, and pharmacodynamic profiles of drugs free from confounding factors.

[0401] Dose selection. For Part 1 (single escalating dose), the expected dose escalation levels are 1000, 2000, and 2000 mg of FCIII-GN3 or placebo. For Part 2 (multiple escalating doses), the expected dose escalation levels are 500, 1000, 2000, and 2000 mg of FCIII-GN3 or placebo. Part 2 subjects may split their day 1 dose and administer it on days 1 and 4 (Part 2b evaluation schedule).

[0402] Based on the high affinity IgG binding by FCIII-GN3 in humans and cynomolgus monkeys, and therefore the low unbound fraction associated with the drug in these species, cynomolgus monkeys are a relevant toxicological species. Completed nonclinical toxicological studies have shown that cynomolgus monkeys tolerate subcutaneous exposure of up to 1000 mg twice weekly for 13 weeks without adverse effects. In this example, the initial 1000 mg subcutaneous dose in cynomolgus monkeys was associated with a combined sex-to-sexual mean AUC of 20,000 μg·h / mL on day 1 and a Cmax of 900 μg / mL, providing predictive margins of 1.45-fold for AUC and 2.0-fold for Cmax for the highest potential study participant dose of 2000 mg. Based on clearance data for FCIII-GN3, drug accumulation is not expected for FCIII-GN3.

[0403] The selected 500 mg multi-stage dose escalation starting dose is the dose already evaluated as a single subcutaneous and intravenous dose in single-stage dose escalation studies (12 active substances and 4 placebos).

[0404] In the single-dose escalation study, the geometric mean Cmax and AUCinf from the intravenous 500 mg cohort were approximately 139 μg / mL and 2,193 μg·h / mL, respectively. In the single-dose escalation study, the geometric mean Cmax and AUCinf from the subcutaneous 500 mg cohort were approximately 115.6 μg / mL and 3172 μg·h / mL, respectively. Tmax was reached 6–12 hours after subcutaneous injection. Given the short half-life (<8 hours) and rapid clearance (~IFN-γ of FCIII-GN3, 99% elimination in 72 hours), it is expected that there would have been no accumulation with weekly repeated dosing or the proposed divided or split dosing schedule.

[0405] The safety margin is calculated as the ratio of the most tolerable first dose exposure in cynomolgus monkeys, a species associated with human safety, to the simulated weekly exposure derived from a human model. [Table 1]

[0406] Pharmacokinetic / pharmacodynamic modeling based on cynomolgus monkey data predicts that subcutaneous administration of 500 mg of FCIII-GN3 will result in an average decrease of approximately 32% in baseline total IgG after administration #1. The predicted average maximum percentage decrease in total IgG after the fourth and final administration (day 22) of the study drug is approximately 64%. The average IgG decrease is predicted to increase with increasing dose and multiple administrations, and the net decrease is predicted to be maximum after the first three administrations. The decrease in IgG approaches a steady state.

[0407] A second optional dosing regimen was introduced in Week 1, where the total dose for Week 1 was divided or fractionated into two equal doses on Day 1 and Day 4, compared to the total dose administered on Day 1 (Part 2b). This approach aims to optimize the initial decline in IgG by using the same total dose given in the divided dosing schedule in Week 1. After Week 1, all dosing returns to a single weekly full-dose schedule for a further three consecutive weeks. The dose division during Week 1 has a negligible effect on the maximum IgG decline after four weeks of weekly dosing. [Table 2]

[0408] Across all subsequent multi-dose cohorts, the total weekly dose of FCIII-GN3 did not exceed that previously evaluated as a single dose in humans, and the predicted exposure associated with repeated dosing of FCIII-GN3 did not exceed the weekly exposure of NOAEL established from preclinical studies.

[0409] FCIII-GN3 is a next-generation immunomodulator designed to offer potential benefits over FcRn-targeting agents (which also reduce IgG levels). Firstly, FCIII-GN3 was designed to selectively and transiently target IgG1, IgG2, and IgG4 while preserving subclass IgG3. IgG3 preservation by FCIII-GN3 is expected to increase the robustness of host defense against a given degree of IgG reduction and may benefit those requiring long-term treatment. Secondly, FCIII-GN3 is a small molecule that enables an easily administered clinical formulation compared to provider-administered subcutaneous formulations of FcRn. Thirdly, FCIII-GN3 is not expected to exhibit the immunogenicity seen in biologics. Fourthly, FCIII-GN3 is expected to have a short half-life in humans, which will ultimately allow for co-administration with standard therapeutic Fc-containing biologics. Finally, FCIII-GN3 is not expected to have effects on albumin, cholesterol, or triglycerides related to the mechanism of action of FcRn.

[0410] Antibodies or antibody fragments that target the neonatal Fc receptor (FcRn) and subsequently reduce IgG are currently being developed to treat multiple immune-related disorders. Importantly, FcRn inhibitor studies have shown no increase in infection, and the reduction in IgG in subjects was up to 85% after approximately 3 months of follow-up.

[0411] The results in humans replicate the findings of the FCIII-GN3 monkey study, which showed dose-dependent and transient decreases in IgG1, IgG2, and IgG4, similar to those observed with FcRn-targeted agents. Maximum IgG declines are expected to occur within 96 hours after each dose. Similar to FcRn, any transient decrease in IgG in humans is predicted to return to 50% of baseline at approximately 2 weeks and to 20% at approximately 4–6 weeks.

[0412] Cumulative evidence based on non-clinical toxicology, previous studies with FcRn inhibitors, and safety data from single-dose escalation studies supports repeated subcutaneous administration of FCIII-GN3 at formulation concentrations up to 250 mg / mL for 4 weeks, with a maximum dose of 2000 mg / week.

[0413] Benefit / Risk Assessment. FCIII-GN3 is administered to subjects solely for research and development purposes and is not expected to provide any benefit to the research subjects. The use of a placebo will not deprive subjects of any potential benefit from FCIII-GN3.

[0414] The primary objective of this example was to evaluate the safety and tolerability of FCIII-GN3 after single and multi-dose subcutaneous administration. A secondary objective was to characterize the pharmacokinetic profile of FCIII-GN3 after single and multi-dose subcutaneous administration. Other objectives included (1) characterizing the pharmacodynamic effects of FCIII-GN3 after single and multi-dose subcutaneous administration; (2) characterizing the binding of FCIII-GN3 to plasma proteins; (3) evaluating the immunogenicity of FCIII-GN3; (4) evaluating the effect of FCIII-GN3 on electrocardiogram parameters after a single dose of FCIII-GN3; and (5) characterizing the urinary pharmacokinetics of a single dose of FCIII-GN3.

[0415] The primary endpoint of this example is safety and tolerability, reported by reporting the frequency of specific subjects with severe AEs and grade 3-4 (CTCAE / DAIDS) that occurred under treatment (Table 1). Secondary endpoints of this example are: (1) Day 1 of Part 1 and Part 2: AUC0-72 hours (for Part 2b), AUC0-96 hours, AUCinf, Cmax, Tmax, T1 / 2, CL / F, and Vd / F; (2) Day 22 of Part 2: AUC0-72 hours (for Part 2b), AUC0-96 hours, AUCinf, Cmax, Tmax, T1 / 2, RAAUC0-96 hours, RACmax, CL / F, and Vd / F.

[0416] The sample size for this study is not determined based on statistical calculations. A sample size of approximately 8 subjects (6 receiving the active drug and 2 receiving placebo) for Part 1 and approximately 10 subjects (8 receiving the active drug and 2 receiving placebo) for Part 2 is deemed appropriate to achieve the objectives of the example. Additional subjects for Part 2 should account for dropouts as a result of the study period.

[0417] This is a single-center, randomized, open-label, placebo-controlled, single-dose and multi-dose trial. This example consists of two parts. Part 1 includes three single-dose cohorts. Part 2 includes four multi-dose cohorts.

[0418] Part 1 Single-Dose Elevation Cohort Each single-dose escalation cohort included approximately 8 subjects. A time-staggered dosing schedule was used for dosing in each single-dose escalation cohort. The schedule included two surveillance subjects who were the first to receive dosing (one active drug, one placebo). The remaining 6 subjects (five active and one placebo) were administered after at least 24 hours of review of available safety and tolerability data from the two surveillance subjects. Part 1: Eligible subjects were randomized on day 1 to receive either active FCIII-GN3 or placebo. The sentinel subject was one randomized active drug and one randomized placebo subject, while the remaining subjects were five randomized active drug and one randomized placebo subject, for a total of approximately 6 subjects receiving FCIII-GN3 and 2 subjects receiving placebo for each single-dose escalation cohort.

[0419] Part 2 Multiple Dose Escalation: Each multiple dose escalation cohort included approximately 10 subjects (8 receiving the active drug and 2 receiving placebo). In Part 2, eligible subjects were randomized on day 1 to receive either active FCIII-GN3 or placebo in a 4:1 ratio. In each multiple dose escalation cohort, a total of approximately 8 subjects received FCIII-GN3 and 2 subjects received placebo.

[0420] FCIII-GN3 was administered subcutaneously to the abdomen. The maximum dose volume administered was 2 mL per syringe per abdominal quadrant. Several syringes were used for dose escalation levels exceeding 500 mg or for the equivalent placebo. To avoid two consecutive doses in the same abdominal quadrant, subsequent doses were rotated to a new abdominal quadrant.

[0421] The timing of investigational drug administration could be consistent for all doses administered to the subjects. Protocol deviations were recorded for any subsequent investigational drug administrations that started or ended more than 60 minutes after the administration time on day 1.

[0422] For detailed preparation and administration procedures, please refer to the IB and Pharmacy Manual.

[0423] Laboratory evaluation and clinical test samples were collected after subjects had fasted for at least 8 hours.

[0424] The glomerular filtration rate (GFL) was calculated using the 2021 CKD-EPI formula: Estimated GFL = 142 x min(Scr / κ,1)α x max(Scr / κ,1)-1.2 x 0.9938 age x 1.012. Scr is serum creatinine (mg / dL), κ is 0.7 for females and 0.9 for males, α = -0.241 (females) or -0.302 (males), min represents the minimum value of Scr / κ or 1.0, and max represents the maximum value of Scr / κ or 1.0.

[0425] The subjects were collected from samples at the time of study for the following pharmacodynamic evaluations: total IgA, total IgE, total IgG (including subclasses IgG1, IgG2, IgG3, and IgG4), total IgM, circulating immune complex C3, circulating immune complex C1q, IL-6, TNFα, IFN-γ, and IL-1-β.

[0426] Serum samples stored in the bank were collected at points within the evaluation schedule. Banked samples may be analyzed at a later date for the following: plasma proteins, markers of inflammation, antibodies (including anti-drug antibodies), immunogenicity, hypersensitivity markers, metabolites, lipids, electrolytes, and hormones.

[0427] A complete description of the statistical analyses performed regarding safety, pharmacokinetic, and pharmacodynamic data was presented in the Statistical Analysis Plan (SAP). The screened population included all subjects who signed the informed consent form.

[0428] The safety population was defined as all subjects who received at least one dose of the investigational drug (FCIII-GN3 or placebo). The safety population was used to summarize all safety assessments.

[0429] The pharmacokinetic population included subjects who received a dose of FCIII-GN3, provided at least one evaluable post-administration pharmacokinetic concentration, and did not experience any protocol deviations or events that would affect pharmacokinetics. The Holter ECG population included all subjects in the safety population who received FCIII-GN3 or placebo with baseline measurements, and who were undergoing treatment and had at least one post-administration time point with valid Holter ECG values. The pharmacokinetic / Holter ECG population included all subjects in the Holter ECG population with at least one pair of post-administration pharmacokinetic concentration and ΔQTcF data from the same time point, as well as subjects in the Holter ECG population who received placebo, with their concentration set to 0.

[0430] Demographic parameters were descriptively summarized. Safety analyses were performed on the safe population.

[0431] Safety and tolerability were assessed by reporting the frequency of patients with severe adverse events (AEs) and grade 3-4 (CTCAE / DAIDS) laboratory abnormalities during treatment. AEs were coded using the latest version of MedDRA.

[0432] Clinical laboratory results were graded according to the numerical clinical laboratory criteria of CTCAE version 5.0 (2017), where available, or according to the DAIDS table revised version 2.1 (2017) for grading the severity of adverse events in adults and children.

[0433] Previous medications and concomitant medications were coded using the latest edition of the World Health Organization Drug Dictionary (WHODrug).

[0434] Pharmacokinetic Parameters The following pharmacokinetic parameters were calculated for FCIII-GN3 plasma concentrations: For days 1 and 22 of Part 1 and Part 2, the following pharmacokinetic parameters were calculated. For Part 2b, the area under the concentration-time curve from time 0 to time 72. For Part 2b, (1) dose-normalized AUC 0-72 hours, area under the concentration-time curve from time 0 to time 96 hours, (2) dose-normalized AUC 0-96 hours, area under the concentration extrapolated from time 0 to infinity, (3) dose-normalized AUC inf, apparent total clearance, maximum observed concentration, (4) dose-normalized Cmax, apparent primary terminal elimination half-life, time at which maximum concentration is observed, and (5) apparent volume of distribution.

[0435] For Part 2, additional pharmacokinetic parameters were calculated based on pharmacokinetics on day 1 and day 22, with the observed accumulation ratio based on AUC0-96 hours, calculated as AUC0-96 hours on day 22 / AUC0-96 hours on day 1. For Part 2b, (1) the observed accumulation rate based on AUC0-72 hours, AUC0-72 hours on day 22 / AUC0-72 hours on day 1, and (2) the observed accumulation ratio based on Cmax, calculated as Cmax on day 22 / Cmax on day 1.

[0436] This implementation was carried out in accordance with ethical principles originating from the Declaration of Helsinki, the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) Guidelines E6 for Clinical Practice (GCP), the Federal Regulation FDA GCP Code (CFR) Title 21 (Part 56), the European Regulation EU 536 / 2014, and the Tri-Council Policy Statement. Example 2 Pharmacokinetics of Compound 4 (IgG degrader) in plasma and IgG in serum after repeated subcutaneous administration of Compound 4 to male cynomolgus monkeys.

[0437] The objective of this example was to determine the pharmacokinetics of compound 4 in plasma and IgG in serum after subcutaneous administration of compound 4 to male cynomolgus monkeys. Compound 4 has the chemical formula C141H219N27O54S2 and a measured molecular weight (g / mol) of 3220.56.

[0438] Nine male cynomolgus monkeys were divided into three groups of three monkeys per group. The monkeys in groups 1, 2, and 3 were administered compound 4 subcutaneously at doses of 3 mg / kg, 10 mg / kg, and 30 mg / kg for two weeks, twice weekly (dose on days 1, 4, 7, and 10). Plasma samples were collected for all groups on both days 1 and 10, before administration, and at 1 / 2 hour, 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, 48 ​​hours, and 72 hours after administration. Serum samples were collected before administration, 24 hours, 48 ​​hours, and 72 hours after administration on days 1 and 10, 120 hours, 168 hours, 240 hours, and 6 hours after administration on day 10, and before administration on day 7. The concentration of compound 4 in the plasma samples was determined by liquid chromatography-tandem mass spectrometry (LC-MS / MS).

[0439] In male cynomolgus monkeys, after subcutaneous administration of compound 4 twice weekly for 2 weeks at doses of 3 mg / kg, 10 mg / kg, and 30 mg / kg, the systemic exposure (AUC0-last) values ​​of compound 4 on day 1 were 277750±45066 ng / mL, 2776846±445099 ng / mL, and 14400603±5351258 ng·h / mL, respectively. The Cmax values ​​were 43795±7168 ng / mL, 226473±68003 ng / mL, and 556662±139888 ng / mL, and the Tmax was reached at 3.33±1.15, 5.33±2.31, and 6.67±2.31 hours, respectively.

[0440] In male cynomolgus monkeys, after subcutaneous administration of compound 4 twice weekly for two weeks at doses of 3 mg / kg, 10 mg / kg, and 30 mg / kg, the systemic exposure (AUC0-last) values ​​of compound 4 on day 10 were 298323±7387 ng·h / mL, 1723297±1061482 ng·h / mL, and 1239382±575287 ng·h / mL, respectively. The Cmax values ​​were 39826±2740 ng / mL, 141552±71614 ng / mL, and 141732±66950 ng / mL, and the Tmax was reached at 4.00±0.00 hours, 4.67±3.00 hours, and 3.33±1.15 hours, respectively.

[0441] On day 1, the AUC0-last of compound 4 increased more significantly than proportionally to the dose (except for the 10 mg / kg to 30 mg / kg range), while the Cmax increased almost proportionally to the dose.

[0442] On day 10, the systemic exposure (AUC0-last and Cmax) to compound 4 increased less proportionally to the dose, except for the increase from 3 mg / kg to 10 mg / kg, where the systemic exposure increased almost proportionally to the dose.

[0443] After subcutaneous administration of compound 4 twice weekly for two weeks, no significant accumulation of compound 4 was observed in male cynomolgus monkeys when comparing systemic exposure (AUC0-last and Cmax) on day 10 versus day 1 at 1 mg / kg and 3 mg / kg. At 30 mg / kg, there was a decrease in exposure on day 10 compared to day 1, with accumulation indices of 0.0861 for AUC0-last and 0.255 for Cmax. All animals showed good tolerance to compound 4 throughout the entire course of the study. No adverse effects were observed during the lifespan of the animals in the study.

[0444] The total IgG percentage decreased sharply from day 1 to day 11 compared to baseline. On day 11, the total IgG% was at its lowest level. On day 11, approximately 93% of total IgG was removed with G3 (30 mg / kg), approximately 72% with G2 (10 mg / kg), and approximately 43% with G1 (3 mg / kg). After day 12, the total IgG% began to rise, and on day 24, the total IgG% was comparable to the level on day 0. The results indicated that total IgG removal was dose-dependent of compound 4, with higher doses of compound 4 resulting in lower total IgG concentrations.

[0445] For the subcutaneous administration route, the following pharmacokinetic parameters were assayed: Cmax (ng / mL), Tmax (hours), T1 / 2 (hours), AUC0-last (ng·h / mL), AUC0-24 (ng·h / mL), and AUC0-inf (ng·h / mL).

[0446] For cynomolgus monkeys, approximately 0.5 mL of blood was collected from each test animal via peripheral blood vessels at each time point. The actual time of each sample collection was recorded.

[0447] Plasma concentrations of compound 4 in experimental animals were subjected to non-compartmental pharmacokinetic analysis using Phoenix WinNonlin software (version 8.3.5, Certara). A linear / logarithmic trapezoidal rule was applied to obtain pharmacokinetic parameters.

[0448] All animals demonstrated sufficient tolerance to compound 4 throughout the entire study. No adverse effects were observed during the in vivo phase of the experiment.

[0449] The actual dose was determined by UPLC-UV.

[0450] a. Pharmacokinetics of compound 4 in animals. In male animals, compound 4 was administered subcutaneously at 3 mg / kg, 10 mg / kg, and 30 mg / kg twice weekly for 2 weeks.

[0451] In male cynomolgus monkeys, after subcutaneous administration of compound 4 twice weekly for 2 weeks at doses of 3 mg / kg, 10 mg / kg, and 30 mg / kg, the systemic exposure (AUC0-last) values ​​of compound 4 on day 1 were 277750±45066 ng·h / mL, 2776846±445099 ng·h / mL, and 14400603±5351258 ng·h / mL, respectively. The Cmax values ​​were 43795±7168 ng·h / mL, 226473±68003 ng·h / mL, and 556662±139888 ng / mL, and the Tmax was reached at 3.33±1.15 hours, 5.33±2.31 hours, and 6.67±2.31 hours, respectively.

[0452] In male cynomolgus monkeys, after subcutaneous administration of compound 4 twice weekly for 2 weeks at doses of 3 mg / kg, 10 mg / kg, and 30 mg / kg, the systemic exposure (AUC0-last) values ​​of compound 4 on day 10 were 298323±7387 ng·h / mL, 1723297±1061482 ng·h / mL, and 1239382±575287 ng·h / mL, respectively. The Cmax values ​​were 39826±2740, 141552±71614, and 141732±66950 ng / mL, and the Tmax was reached at 4.00±0.00 hours, 4.67±3.0 hours, and 3.33±1.15 hours, respectively.

[0453] On day 1, the AUC0-last of compound 4 increased more significantly than proportionally to the dose (except for the 10 mg / kg to 30 mg / kg range), while the Cmax increased almost proportionally to the dose.

[0454] On day 10, the systemic exposure (AUC0-last and Cmax) to compound 4 increased less proportionally to the dose, except for the increase from 3 mg / kg to 10 mg / kg, where the systemic exposure increased almost proportionally to the dose.

[0455] After subcutaneous administration of compound 4 twice weekly for two weeks, no significant accumulation of compound 4 was observed in male cynomolgus monkeys when comparing systemic exposure (AUC0-last and Cmax) on day 10 versus day 1 at 1 mg / kg and 3 mg / kg. At 30 mg / kg, there was a decrease in exposure on day 10 compared to day 1, with accumulation indices of 0.0861 for AUC0-last and 0.255 for Cmax. All animals showed good tolerance to compound 4 throughout the entire course of the study. No adverse effects were observed during the in vivo phase of the examples.

[0456] Assay results were collected for individual mean plasma concentrations (ng / mL) of compound 4 on day 1 in male cynomolgus monkeys after subcutaneous administration of compound 4 at 3 mg / kg twice weekly for 2 weeks. Individual and mean plasma concentrations of compound 4 are shown.

[0457] Assay results were collected in male cynomolgus monkeys for individual compound 4 and the mean plasma concentration of compound 4 on day 1, after 2 weeks of subcutaneous administration of compound 4 at 10 mg / kg twice weekly, in the form of ng / mL. Individual and mean plasma concentrations of compound 4 are shown.

[0458] Assay results were collected for the mean plasma concentrations (ng / mL) of individual compounds 4 in male cynomolgus monkeys on day 1, after subcutaneous administration of compound 4 at 30 mg / kg twice weekly for 2 weeks. Individual and mean plasma concentrations of compound 4 are shown.

[0459] Assay results were collected for individual mean plasma concentrations of compound 4 at day 10 in male cynomolgus monkeys after subcutaneous administration of compound 4 at 3 mg / kg twice weekly for 2 weeks. Individual and mean plasma concentrations of compound 4 are shown.

[0460] Assay results were collected for each individual on day 10, and the mean plasma concentration (ng / mL) of compound 4 in male cynomolgus monkeys was collected after subcutaneous administration of compound 4 twice weekly at 10 mg / kg for two weeks. Individual and mean plasma concentrations of compound 4 are shown.

[0461] Assay results were collected for the mean plasma concentrations (ng / mL) of individual compounds 4 in male cynomolgus monkeys on day 10, after subcutaneous administration of compound 4 at 30 mg / kg twice weekly for two weeks. Individual and mean plasma concentrations of compound 4 are shown.

[0462] Assay results were collected for the mean plasma pharmacokinetic parameters of compound 4 on days 1 and 10 in male cynomolgus monkeys after subcutaneous administration of compound 4 twice weekly over a two-week period. The mean plasma pharmacokinetic parameters of compound 4 after subcutaneous administration of compound 4 at 3 mg / kg, 10 mg / kg, and 30 mg / kg in male animals are shown.

[0463] Assay results were collected for individual parameters and mean plasma pharmacokinetic parameters of compound 4 on day 1 in male cynomolgus monkeys after subcutaneous administration of compound 4 at 3 mg / kg twice weekly for two weeks. Individual and mean plasma pharmacokinetic parameters of compound 4 are shown in male animals after subcutaneous administration of compound 4 at 3 mg / kg, 10 mg / kg, and 30 mg / kg twice weekly for two weeks.

[0464] Assay results were collected for day 1. Individual and mean plasma pharmacokinetic parameters of compound 4 in male cynomolgus monkeys after twice-weekly subcutaneous administration of compound 4 at 3 mg / kg, 10 mg / kg, and 30 mg / kg over two weeks in male animals are shown.

[0465] Assay results were collected for individual mean plasma pharmacokinetic parameters of compound 4 on day 1 in male cynomolgus monkeys after 2 weeks of subcutaneous administration of compound 4 at 30 mg / kg twice weekly. Individual mean plasma pharmacokinetic parameters of compound 4 are shown after 2 weeks of subcutaneous administration of compound 4 at 3 mg / kg, 10 mg / kg, and 30 mg / kg in male animals.

[0466] Assay results were collected for individual and mean plasma pharmacokinetic parameters of compound 4 at day 10 in male cynomolgus monkeys after subcutaneous administration of 3 mg / kg of compound 4 twice weekly for 2 weeks. Individual and mean plasma pharmacokinetic parameters of compound 4 are shown after subcutaneous administration of 3 mg / kg, 10 mg / kg, and 30 mg / kg of compound 4 twice weekly for 2 weeks in male animals.

[0467] Assay results were collected for individual parameters and mean plasma pharmacokinetic parameters of compound 4 at day 10 in male cynomolgus monkeys after subcutaneous administration of 10 mg / kg of compound 4 twice weekly for 2 weeks. Individual parameters and mean plasma pharmacokinetic parameters of compound 4 were collected after subcutaneous administration of 3 mg / kg, 10 mg / kg, and 30 mg / kg of compound 4 twice weekly for 2 weeks in male animals.

[0468] Assay results were collected for day 10. Individual plasma pharmacokinetic parameters and mean plasma pharmacokinetic parameters of compound 4 in male cynomolgus monkeys after subcutaneous administration of compound 4 twice weekly at 30 mg / kg for 2 weeks. Individual plasma pharmacokinetic parameters and mean plasma pharmacokinetic parameters of compound 4 after subcutaneous administration of compound 4 twice weekly at 3 mg / kg, 10 mg / kg, and 30 mg / kg in male animals for 2 weeks at 3 mg / kg, 10 mg / kg, and 30 mg / kg.

[0469] Assay results were collected to assess the dose-proportionality of compound 4 in male cynomolgus monkeys after subcutaneous administration of compound 4 twice weekly over a two-week period. We present an evaluation of the dose-proportionality of systemic exposure to compound 4 in animals.

[0470] Assay results were collected to determine the accumulation index of compound 4 in male cynomolgus monkeys after subcutaneous administration of compound 4 twice a week for two weeks.

[0471] Assay results were collected for individual and mean body weight (kg) in male cynomolgus monkeys after subcutaneous administration of compound 4 at 3 mg / kg twice weekly over a two-week period.

[0472] Assay results were collected for individual body weight and mean body weight (kg) in male cynomolgus monkeys after subcutaneous administration of compound 4 at 10 mg / kg twice weekly over a two-week period.

[0473] Assay results were collected for individual body weight and mean body weight (kg) in male cynomolgus monkeys after subcutaneous administration of compound 4 at 30 mg / kg twice weekly over a two-week period. Detection of total IgG levels in the serum of cynomolgus monkeys

[0474] Serum preparation for IgG analysis: Each blood sample (approximately 0.5 mL per time point) was collected from a peripheral vein in each animal and placed in a commercially available BD tube containing polymer silica activator, and allowed to stand at room temperature for at least 30 minutes. The samples were centrifuged within 1 hour of collection (3200 × g, 2°C to 8°C for 10 minutes). Each serum sample (approximately 0.2 mL) was divided into two aliquots of approximately 0.1 mL each (one for primary absorption and the other for backup).

[0475] Kit information. Human / MHP IgG kit, MSD, catalog number K150JLD-2, lot number: K00E0645.

[0476] Equipment information: MESO QuickPlex SQ 120 MM.

[0477] Detection Protocol This MSD plate is pre-coated with capture antibody. (1) Block the plate. Add 150 μl of blocker A solution to each well. Seal the plate with adhesive plate seals and incubate at room temperature with shaking for 30 minutes. (2) Wash and add sample. Wash the plate three times with 150 μl / well of phosphate-buffered saline-Tween. Add 25 μl of diluted sample or calibrator per well. Seal the plate with adhesive plate seals and incubate at room temperature with shaking for 2 hours. (3) Wash and add detection antibody solution. Wash the plate three times with at least 150 μl / well of phosphate-buffered saline-Tween. Add 25 μl of detection antibody solution to each well. Seal the plate with adhesive plate seals and incubate at room temperature with shaking for 2 hours. (4) Wash and read. Wash the plate three times with 150 μl / well of phosphate-buffered saline-Tween. Add 150 μl of 2×Read Buffer T to each well. Read the plate on the MSD instrument.

[0478] The total IgG percentage decreased sharply from day 1 to day 11 compared to baseline. On day 11, the total IgG% was at its lowest level. Approximately 93% of total IgG was removed at G3 (30 mg / kg). Approximately 72% of total IgG was removed at G2 (10 mg / kg). On day 11, approximately 43% of total IgG was removed at G1 (3 mg / kg). After day 12, the total IgG% began to rise, and on day 24, the total IgG% was comparable to the level of day 0. The results indicated that total IgG removal was dose-dependent of compound 4, with higher doses of compound 4 administered resulting in lower total IgG concentrations. Summary of the method for Compound 4. Acceptance criteria for performing biological analysis.

[0479] The concentration of compound 4 in the bioanalytical plasma was determined using LC-MS / MS.

[0480] Calibration curve: Sample analysis should be performed simultaneously with a set of calibration standards using an established LC-MS / MS method. A minimum of six calibration standards should be calculated back to within ±20% of their nominal values ​​in plasma.

[0481] Quality Control (QC): Sample analysis should be performed simultaneously on two sets of quality control samples using an established LC-MS / MS method. The quality control sample sets for this method consist of low, medium, and high concentrations. At least four of the six quality control samples should be calculated back to within ±20% of their nominal values ​​in plasma.

[0482] Specificity and Sensitivity: Calibration curves consist of at least six non-zero calibration standards for each LC-MS / MS method, and the limit of quantification of the target is ≤5 ng / mL. The mean calculated concentration in a single blank matrix should be ≤0.5 times the limit of quantification.

[0483] Carryover: The average calculated carryover response in the blank immediately after injection of the best standard substance should be below the lower limit of quantification.

[0484] Biological matrix. Plasma blanks from male cynomolgus monkeys were used, along with K2-EDTA as an anticoagulant, to prepare calibration standard (C) and quality control samples.

[0485] Sample preparation. For plasma preparation (for 100-40000 ng / mL), a 20 μL aliquot of the sample was quenched with 200 μL of internal standard solution (100 ng / mL labetalol, 100 ng / mL tolbutamide, 100 ng / mL verapamil, 100 ng / mL dexamethasone, 100 ng / mL glybride, and 100 ng / mL celecoxib in 0.1% FA-containing ACN / MeOH (25:75, v / v)). The mixture was vortex-mixed at 800 rpm for 10 minutes and centrifuged at 3220 × g for 15 minutes at 4°C. A 50 μL aliquot of the supernatant was transferred to another clean 96-well plate and centrifuged at 3220 × g for 5 minutes at 4°C. The supernatant was then injected into LC-MS / MS.

[0486] If the analyte is relatively polar, the supernatant may be further diluted as follows: A 10 μL aliquot of the supernatant was transferred to another clean 96-well plate, diluted with 100 μL of ACN / MeOH (25:75, v:v) containing 0.1% FA, vortexed at 800 rpm for 10 minutes, centrifuged at 3220 × g, 4°C for 5 minutes, and then injected for LC-MS / MS analysis.

[0487] Plasma preparation procedure for concentrations of 5-5000 ng / mL. Quench a 20 μL aliquot of the sample with 200 μL of internal standard solution (100 ng / mL labetalol, 100 ng / mL tolbutamide, 100 ng / mL verapamil, 100 ng / mL dexamethasone, 100 ng / mL glybride, and 100 ng / mL celecoxib in 0.1% FA-containing ACN / MeOH (25:75, v / v)). Vortex mix the mixture at 800 rpm for 10 minutes and centrifuge at 3220 × g for 15 minutes at 4°C. Transfer a 50 μL aliquot of the supernatant to another clean 96-well plate and centrifuge at 3220 × g for 5 minutes at 4°C. The supernatant was then injected into LC-MS / MS.

[0488] Data processing. MultiQuant 3.0.3 software was used to process the data for all samples. The regression mode was quadratic with 1 / x² as the weight coefficient. Example 3 Sustained reduction of Gd-IgA by compound 1 (Gd-IgA1 degrader) in IgA nephropathy research.

[0489] Compound 1 is used for the treatment of circulating pathogenic serum galactose-deficient immunoglobulin A1 (Gd-IgA nephropathy (IgAN), IgA1). Compound 1 is conjugated with an asialoglycoprotein receptor (ASGPR) binding moiety to promote hepatic removal of bound Gd-IgA1, followed by endolysosomal degradation. For further information on Compound 1, please refer to International Publication No. 2024 / 228935, brochure by Biohaven Therapeutics, Inc.

[0490] IgAN is the most common form of glomerulonephritis worldwide, presenting with a wide range of clinical manifestations, from gross hematuria following an episode of respiratory or gastrointestinal infection to insidious or rapidly progressive renal failure. The central finding in IgAN patients is Gd-IgA1 and associated anti-Gd-IgA1 autoantibodies. (See Knoppova et al., J. Clin. Med., 10(19)(2021).) Gd-IgA1 plays a central role in the pathogenesis of the disease, thereby circulating Gd-IgA1 binding to immunoglobulins and forming immune complexes that deposit in the glomeruli. These immune complexes are nephritis-inducing, inducing glomerulonephritis, leading to mesangial cell proliferation and progressive forms of renal damage. Local and systemic activation of the renin-angiotensin system and complement activation ultimately lead to glomerulosclerosis and tubulointerstitial fibrosis, accompanied by loss of renal function. Clinical evidence supports the deposition of IgA1 immune complexes in the initiation and propagation of Gd-IgA1 kidney pathology. Both Gd-IgA1 and associated immune complexes directly address the pathogenesis of the disease and therefore represent an attractive therapeutic approach for patients with IgAN.

[0491] Compound 1 targets pathogenic Gd—IgA1-IgA1 and its immune complexes for proteolysis by selectively and directly degrading the circulating levels of both Gd. By selectively removing Gd—IgA1—compound 1 avoids the immunosuppression seen in non-selective degraders. Compound 1 removes IgA1 in Gd-IgAN, pathogenic immunoglobulins, and immune complexes without widespread immunosuppression. For further details, see the Compound 1 Investigator's Brochure.

[0492] Compound 1 is a galactose-deficient IgA1 (Gd-IgA1) TRAP degrader that achieved a deep, rapid, and sustained reduction of Gd-IgA1 for the treatment of IgA nephropathy.

[0493] IgA nephropathy is the leading cause of glomerular disease worldwide. IgA nephropathy is generally diagnosed in individuals within 20-30 years of age, and most individuals progress to renal failure over the following 10-15 years. As an immune system disorder, IgA nephropathy frequently relapses, even after kidney transplantation. While the 2021 KDIGO treatment guidelines recommended only standard chronic kidney disease treatment, the 2024 draft guidelines emphasize the importance of treating the underlying immune disorder by eliminating the abnormal form of IgA. Galactose-deficient IgA1 is the underlying abnormality of IgA nephropathy. This is a group of IgA molecules that have a change in sugar on the IgA1 hinge region, which fundamentally alters how this antibody behaves. It promotes immune complex formation, as well as glomerular injury and damage, and facilitates the loss of renal function.

[0494] In this example, a single subcutaneous dose of compound 1 at a dose of 500 mg achieved a rapid, deep, and sustained reduction of up to 81% of Gd-IgA1, with a median reduction of 66% (Figure 1). The reduction occurred within hours of each administration, progressed, and persisted for several weeks after the single dose. The effect was selective, and no significant reduction was induced in other immunoglobulins: IgA, IgG, IgD, IgE, or IgM.

[0495] (A selective approach using compound 1 has the potential to provide an improved safety profile compared to broad-spectrum immunosuppressants. Compound 1 was safe and well-tolerated throughout the ongoing study. There were no serious or severe adverse events associated with the drug. Compared to placebo over a 4-week treatment period, there were no clinically significant increases in alanine aminotransferase, aspartate aminotransferase, or bilirubin, no clinically significant decreases in albumin, and no clinically significant increases in cholesterol. Compared to baseline, there were no clinically significant decreases in other immunoglobulins, including IgG, IgA, IgD, IgE, or IgM.)

[0496] Gd-IgA1 levels were the same in both healthy volunteers and patients with IgAN, and were present in excess in patients with IgAN. Suppressed levels of Gd-IgA1 were observed in healthy subjects. The same effect was seen in patients with IgA nephropathy.

[0497] The graph on the left shows the decrease in Gd-IgA levels mediated by Gd-IgA degrader compound 1 after intravenous ("IV") administration. The graph on the right shows the decrease in Gd-IgA levels mediated by Gd-IgA degrader compound 1 after subcutaneous ("SC") administration. The decrease in Gd-IgA1 persists longer after subcutaneous administration.

[0498] Compound 1 differs from alternative approaches due to its precision. Drugs targeting glucocorticoid receptors may have steroid-like side effects, drugs targeting complement require vaccination for encapsulated bacterial infections, and B-cell targeted therapies cause a reduction in all immunoglobulin isotypes, potentially increasing the risk of long-term infections.

[0499] Compound 1 specifically targets the underlying abnormalities in IgA nephropathy, while leaving the rest of the immune system intact. Therefore, it has the potential to deprive the key driving factors for immune complex formation while leaving other antibodies completely unaffected, which means it possesses efficacy with unparalleled safety.

[0500] Controlled single-dose and multiple-dose escalation trials to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of Compound 1 in a placebo-controlled environment. This study is a single-center, randomized, placebo-controlled, sequential single-dose / multiple-dose escalation trial conducted in three parts.

[0501] Part 1 – Single-Dose Escalation Cohort (Intravenous): Each cohort consisted of approximately 8 subjects out of a total of approximately 48 subjects (6 subjects received the active substance and 2 subjects received placebo). On day 1, subjects received a single intravenous dose of compound 1 at planned doses of 125 mg, up to 250 mg, and up to 500 mg, or placebo. Subsequent cohorts may explore lower or intermediate doses of compound 1. Predicted exposure at the highest dose did not exceed NOAELs from animal toxicology studies.

[0502] Part 2 – Multiple Dose Escalation Cohorts (Intravenous). Multiple dose escalation cohorts received a total of three doses intravenously weekly. While the multiple dose escalation cohorts were in progress, medication in the subsequent single dose escalation panel continued. The multiple dose escalation portion consisted of approximately five cohorts (one cohort per dose level). Each cohort included approximately eight subjects out of a total of approximately 40 subjects (six subjects received the active substance and two subjects received placebo). Subjects were randomized (3:1) within each dose panel on day 1 and received compound 1 or the corresponding placebo on days 1, 8, and 15. Subjects in each multiple dose escalation cohort received three intravenous doses of compound 1 or placebo once a week at a planned dose ranging from 125 mg to 500 mg.

[0503] Part 3 – Single-Dose Escalation Cohort (Subcutaneous). Up to three cohorts may be completed. Each cohort included approximately 8 subjects (6 receiving the active substance and 2 receiving placebo) out of a total of approximately 24 subjects. The first subcutaneous single-dose escalation cohort was initiated after the dose to be used had been tested in the intravenous single-dose escalation cohort and safety, tolerability, and pharmacokinetic data were available. Subjects received a single subcutaneous dose of compound 1 or placebo on day 1. The starting dose of compound 1 was up to 500 mg. Subsequent doses were selected based on new data from the intravenous single-dose escalation and multi-dose escalation cohorts as well as from previous subcutaneous cohorts. Predicted exposure at the highest dose did not exceed the NOAEL (No Observed Adverse Effect Level) from animal toxicology studies.

[0504] Approximately 112 non-pregnancy potentials are planned to be enrolled in the study: 48 with a single escalating dose (intravenous) in Part 1, 40 with multiple escalating doses in Part 2, and 24 with a single escalating dose in Part 3.

[0505] Dosage and follow-up periods may be modified based on new safety and pharmacokinetic data.

[0506] The main objectives of this study are (1) to evaluate the safety and tolerability of single and multi-dose intravenous administration of compound 1 in the subjects, and (2) to evaluate the safety and tolerability of single-dose subcutaneous administration of compound 1 in the subjects.

[0507] (The second objectives of this study were to evaluate the plasma pharmacokinetics (PK) of single and multi-dose intravenous administration of compound 1 in subjects, to evaluate the plasma pharmacokinetics (PK) of single-dose subcutaneous administration of compound 1 in subjects, and to observe the electrocardiogram (ECG) parameters (QTcF, PR interval, QRS complex, heart rate, rate [HR], and T-waveform morphology) after a single intravenous administration in subjects.)

[0508] Other objectives of this study are: (1) to evaluate the pharmacodynamic (PD) effects of single and multiple doses of compound 1 in one subject; (2) to evaluate the immunogenicity of compound 1 after single and multiple doses in the subject; and (3) to evaluate the metabolic profile of compound 1 in plasma.

[0509] The primary endpoints of this example were: (1) Safety and tolerability were assessed by reporting the frequency of adverse events and unique subjects with grade 3 and grade 4 laboratory abnormalities. The secondary endpoints of this example were: (1) For the intravenous single-dose escalation cohort: Area under the concentration-time curve (AUC) (AUCinf) from time zero to infinity, AUC (AUC0-t) from time zero to the last quantifiable observation, maximum observed plasma concentration (Cmax), time to maximum observed plasma concentration (Tmax), apparent primary terminal detachment rate constant (T1 / 2), total plasma clearance (CL), and volume of distribution (Vd). (2) For the subcutaneous single-dose escalation cohort: A UCinf, AUC0-t, Cmax, Tmax, Tlag, T1 / 2VdΔF and CL / F were calculated. (3) For day 1 in multiple dose-escalating cohorts: AUC(AUC0-168), Cmax, minimum observed plasma concentration (Cmin), Tmax from 0 to 168 hours. (4) For day 15 in multiple dose-escalating cohorts: AUC(AUCtau) for one dosing interval (τ) in steady state, maximum observed concentration (Cmax) in steady state. ss) Minimum observed concentration during the steady-state dosing interval (Cmin ss), mean observed concentration interval during one dosing (Cav ss), time to the maximum plasma concentration observed at steady state (Tmax ss), steady-state plasma concentration at the end of one dosing interval (Ctau), observed accumulation rate based on AUCtau (RA) (AUCtau), accumulation rate max based on observed C (RACmax), clearance at steady state (CLss), volume of distribution at steady state (Vd, ss), variation ((Cmax ss - Cmin ss) / Cav ss). (5) For single dose escalation (intravenous) in Part 1: (a) Cardiac parameters measured by Holter walking monitoring, e.g., HR, QTcF, PR, QRS (ΔHR, ΔQTcF, ΔPR, ΔQRS). (b) Corrected ΔHR, ΔQTcF, ΔPR, and ΔQRS (ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS) calculated from a mixed model of repeated measures, including outliers in placebo-HR, QTcF, PR, and QRS. (c) Frequency of treatment-T-wave morphology and presence of U-waves.(6) A model for placebo-corrected baseline-adjusted QTcF (ΔΔQTcF) between concentration-response (CR) plasma concentration and the change from baseline in the QTcF parameter.

[0510] Primary pharmacological compound 1 is a non-clinical in vitro and in vivo primary pharmacological study of a deglycosylated IgA (Dg-IgA, an enzymatic surrogate of Gd-IgA1) degradant. Compound 1 effectively promotes the hepatic uptake and degradation of Gd-IgA1 via the endolysosomal system, targeting ASGPR (KD=14.6 μM) and Gd-IgA1 (KD=1.8 nM).

[0511] Compound 1 uses targeted proteolytic degradation to target Gd-IgA1 and its immune complex. Compound 1 is a bifunctional chimeric antibody conjugate designed to selectively recognize, bind to, and target circulating pathogenic Gd-IgA1 for ASGPR-mediated degradation in hepatocytes.

[0512] Biophysical and cell-based assay results suggest that compound 1 selectively binds to deglycosylated IgA complexes, leaving fully glycosylated IgA1, and mediates their in vitro internalization at low nanomolar concentrations.

[0513] Safety Pharmacology - Neurobehavioral Evaluation in Rats: Compound 1 was administered intravenously to male and female Wisterhan rats every other day for up to 29 days via slow bolus injection (lasting at least 2 minutes). Every-other-day administration of Compound 1 was not associated with changes in neurobehavioral function at doses up to 500 mg / kg / dose.

[0514] (Safety pharmacology. Electrocardiogram examination in monkeys. In a 1-month repeated-dose toxicity study, compound 1 was administered by slow intravenous bolus injection over 3-5 minutes to cynomolgus monkeys, and electrocardiograms were measured once during adaptation, once at week 4, and once during recovery. No abnormalities in electrocardiogram rhythm or waveform morphology were observed for compound 1. No effect of compound 1 on heart rate, respiratory rate interval, PR interval, QRS duration, QT interval, or corrected QT interval was observed at any dose level, based on comparison with group-mean preliminary test values ​​and control values.)

[0515] Safety Pharmacology – Respiratory Rate and Blood Pressure in Cynomolgus Monkeys. Cynomolgus monkeys and macaques were evaluated for respiratory rate and blood pressure as part of a repeated-dose study, once during the acclimatization period, once at week 4, and once during recovery. No compound 1-related effects on blood pressure or respiratory rate were observed during the drug administration and recovery periods.

[0516] The concentration of pharmacokinetic compound 1 was quantified in plasma samples using two bioanalytical methods due to the complex nature of compound 1. The whole antibody method (referred to as Tab) binds at the Fc region of the antibody moiety, while the whole conjugate method (referred to as Tc) binds at the ASGPR binding region. The Tab method detects all DRMs containing the antibody moiety of compound 1. The Tc method detects only DRMs containing the ASGPR binding region. Combining these methods provides a more complete understanding of exposure to compound 1 and related species.

[0517] Absorption. Single-dose non-GLP pharmacokinetic studies were performed in male nude mice administered compound 1 by intravenous bolus and subcutaneous injection, with or without the presence of deglycosylated IgA. Plasma exposure to compound 1 with and without co-administration of deglycosylated IgA was not observed to differ significantly. The clearance of compound 1 was low, ranging from 0.024 to 0.0879 L / hr / kg over the investigated dose range. The steady-state volume of distribution (Vss) of compound 1 ranged from 0.96 to 1.62 L / kg over the investigated dose range, and was greater than the total body water content. Subcutaneous bioavailability in mice ranged from 23% to 91% using the nearest suitable intravenous dose, with Cmax values ​​of 2.81 and 6.69 (μg / mL / kg). Tmax values ​​ranged from 26.7 hours to 48 hours, indicating slow absorption.

[0518] As part of the tolerability study, the toxicological kinetics of compound 1 were determined in cynomolgus monkeys administered a single slow intravenous bolus or subcutaneously. The mean Cmax increased almost proportionally to the dose. The mean AUC increased more significantly than proportionally to the dose. The difference in exposure between males and females was generally less than twofold. The mean subcutaneous bioavailability was low (ranging from 2.20% to 9.05%), and the Tmax ranged from 4.5 to 27 hours, indicating slow absorption.

[0519] Repeated-dose toxicological studies were conducted in Sprague-Dawley rats, Wistar Han rats, and cynomolgus monkeys. After repeated administration, the mean Cmax and the dose-mean AUC increased more significantly than the dose-proportional ratio. No accumulation was observed.

[0520] The in vivo metabolism of compound 1 was investigated by analyzing rat plasma and liver homogenate samples on day 9 after intravenous administration of 300 mg / kg every other day. Qualitative analysis of the metabolic fate of compound 1 in plasma revealed a total of eight metabolites. M1350 (amide hydrolysis and O-dealkylation of acetylglucosamine) was detected as the major circulating drug-related substance (excluding compound 1) in rat plasma after intravenous administration (AUC0-24), and based on MS response, constituted over 76% of the drug-related substances in plasma. Qualitative analysis of the metabolic fate of compound 1 in liver homogenate revealed a total of eight metabolites, including M1350 as the major drug-related substance (excluding compound 1), which constituted over 83% of the total. Similar metabolic profiles were observed for compound 1 in rat plasma and liver.

[0521] The in vivo metabolism of compound 1 was investigated by analyzing cynomolgus monkey plasma samples after a single intravenous dose of 500 mg / kg. Qualitative testing of the metabolic fate of BHV1400 in plasma revealed a total of six metabolites. M1350 (amide hydrolysis and O-dealkylation of acetylglucosamine) was detected as the major circulating drug-related substance in cynomolgus monkey plasma (AUC0-24 pool) after intravenous administration, constituting over 66% of the total in both female and male cynomolgus monkeys based on MS response. Similar metabolic profiles were observed in the plasma of female and male cynomolgus monkeys.

[0522] Single-dose toxicity. Cynomolgus monkeys were administered escalating single doses of compound 1 by slow bolus intravenous injection over 2–5 minutes at 10 mg / kg / day, 30 mg / kg / day, 100 mg / kg / day, 300 mg / kg / day, and 500 mg / kg / day, as well as by a single subcutaneous dose of 100 mg / kg. All doses up to 500 mg / kg / day (intravenous and subcutaneous) were well tolerated with limited differences in clinicopathological parameters (increased C-reactive protein and decreased inorganic phosphorus levels) at 10 mg / kg / day and 30 mg / kg / day on day 2. At the highest dose level tested (500 mg / kg / day), the Cmax and AUClast for Tab and Tc (combined males and females, respectively) were 13,500 and 13,900 μg / mL, respectively, and the AUClast was 366,000 and 233,000 h·μg / mL. Furthermore, as assessed by the AUC0-72 value, the bioavailability of compound 1 when administered to cynomolgus macaques via subcutaneous injection at a single dose of 100 mg / kg / dose was 9.05% for Tab (combined males and females; 11.6% for females and 6.95% for males), and 6.56% for Tc in females and 2.20% in males.

[0523] Repeated-dose toxicity. Compound 1 was administered to Wisterhan rats every other day by intravenous injection over at least 2 minutes for a total of five doses: 0, 30, 100, and 300 mg / kg / dose. There were no compound 1-related effects on studies of clinical observation, body weight or weight gain, food consumption, clinicopathological parameters (hematology, coagulation, and clinical chemistry), or anatomical pathological parameters (organ weight, gross observation, or microscopic results). The NOAEL was 300 mg / kg / dose (highest dose tested). Plasma concentrations on day 9 were 6,300 μg / mL and 25,600 h·μg / mL for Tab Cmax and AUClast, respectively, and 6,220 μg / mL and 21,100 h·μg / mL for Tc Cmax and AUClast, respectively.

[0524] Compound 1 was administered intravenously to Wistar Han rats for 29 days (15 doses) every other day for at least 2 minutes, along with a vehicle, at doses of 50 mg / kg / dose, 150 mg / kg / dose, or 500 mg / kg / dose. No compound 1-related mortality or definitive effects were observed in clinical / veterinary observations, body weight, food consumption, ophthalmic assessment, neurobehavioral assessment, hematology, coagulation, urinalysis, urinalysis, and renal biomarker parameters, cytokine parameters, organ weight, or macroscopic or microscopic assessments. No adverse outcomes were observed in any of the parameters evaluated up to (including) 500 mg / kg / dose. The NOAEL was 500 mg / kg / dose (the highest dose evaluated). At a dose of 500 mg / kg, the sex-combined Cmax and AUC were 9,750 μg / mL and 43,700 h·μg / mL, respectively, for Tab, and 9,990 μg / mL and 39,200 h·μg / mL, respectively, for Tc.

[0525] Male and female cynomolgus monkeys were intravenously administered compound 1 at vehicle doses of 30, 100, or 300 mg / kg / dose three times a week on days 1, 5, 7, 9, 11, 13, 17, 19, 21, 23, 25, 27, and 29. All animals survived to the planned end of treatment. There were no clinical observations associated with compound 1. There were no compound 1-related effects on body weight, food consumption, ophthalmology, electrocardiogram including blood pressure and respiratory rate, as well as on hematological, coagulation, urinalysis, and urinary chemistry parameters. No adverse outcomes were observed for any parameter evaluated up to (including) 500 mg / kg / dose. The NOAEL was 500 mg / kg / dose (the highest dose evaluated). At a dose of 500 mg / kg, the sex-combined Cmax and AUC were 9,750 μg / mL and 43,700 h·μg / mL, respectively, for Tab, and 9,990 μg / mL and 39,200 h·μg / mL, respectively, for Tc.

[0526] Local tolerability was evaluated in 1-month repeated intravenous toxicity studies in rats and cynomolgus monkeys. In the rat and cynomolgus monkey studies, there was no effect at the injection site, which differed from the vehicle control.

[0527] Local tolerability was evaluated in New Zealand white rabbits by single-dose subcutaneous administration to 3 males and 3 females per dose group. The vehicle and 125 or 250 mg / kg doses were administered to the right and left scapular regions of each rabbit. Mortality, clinical observations, skin scores, body weight, weight gain, and macroscopic and microscopic examination of selected tissues were evaluated in this study.

[0528] During the course of this study, there were no unplanned deaths or clinical observations related to the test substance. Body weight was similar for all animals throughout the study, and there were no macroscopic pathological or microscopic findings related to the test substance.

[0529] Skin observations attributable to compound 1 were minimal and limited to grade 1 erythema and edema in one female patient at 125 mg / kg / day on day 2, grade 1 erythema in one male patient at 250 mg / kg / day on day 3 (which resolved by day 4), grade 1 erythema and edema in one female patient at 250 mg / kg / day on day 2, and grade 1 erythema on days 2 and 3 and grade 1 edema on days 2–4 in another female patient at 250 mg / kg / day.

[0530] In conclusion, administration of compound 1 as a single subcutaneous injection was well tolerated in rabbits at levels of 125 and 250 mg / kg / day, with only minimal skin irritation observed, mainly in females. Macroscopic and microscopic pathological results were considered to be procedure-related and not related to the administration of compound 1.

[0531] Immunotoxicity. (Human whole blood was collected, and peripheral blood mononuclear cells (PBMCs) were isolated from 10 human donors (5 males and 5 females). PBMCs and whole blood were treated in vitro with compound 1 at various concentrations. There was no effect on cytokine release (IFN-γ, IL-2, IL-6, IL-10, IL-1β, and TNF-α) that could be attributed to BHV1400. All observed changes were generally sporadic and small in magnitude. Among the positive controls, anti-CD3 and lipopolysaccharides resulted in the expected increases in all cytokines except IL-2.)

[0532] The rationale for conducting the study was to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of compound 1 after intravenous and subcutaneous administration of single-dose and multiple-dose intravenous escalating doses in adult subjects.

[0533] Single-Dose Elevation Intravenous Cohort - Starting Dose and Dose Elevation The calculation of the starting dose for the single-dose elevation portion of this study was based on the methodology described in the FDA Guidance on Estimating the maximum Safe Starting Dose in Initial Clinical Trials for Therapeutics in Adult Healthy Volunteers, taking into account the recommendations described in the EMA Guideline on Strategies to Identify and Mitigate Risks for First-in-human and Early Clinical Trials with Investigational Medicinal Products.

[0534] The starting human dose of 125 mg of compound 1 was selected based on a combination of data from nonclinical pharmacological, pharmacokinetic, and toxicological studies, while allowing a safety factor of ≥45 times the human equivalent dose (HED) of the NOAEL in rats and cynomolgus monkeys to maximize participant safety and support the full dose range for safety assessment and pharmacokinetic analysis purposes.

[0535] Preclinical 28-day toxicity studies were conducted in rats and cynomolgus monkeys. The highest doses tested in both species were their respective NOAELs (500 mg / kg in rats and 300 mg / kg in cynomolgus monkeys), resulting in human equivalent doses of 80.6 mg / kg and 96.8 mg / kg, or uniform doses of 5645 mg and 6774 mg, assuming a body weight of 70 kg, respectively. Applying a safety factor of 10, the rat NOAEL corresponds to a maximum recommended starting dose (MRSD) of approximately 560 mg for a 70 kg human. Compound 1 was quantified using two bioanalytical methods (Tc and Tab).

[0536] Pharmacokinetic / pharmacodynamic modeling and translational simulations were performed to support dose selection and dose justification for compound 1. The pharmacokinetic / pharmacodynamic model was constructed using a human Gd-IgA1 analog (Dg-IgA). The pharmacokinetics of compound 1 were described using a simplified target-mediated pharmacokinetic (TMDD) model with constant receptor levels. The final population pharmacokinetic / pharmacodynamic model was a one-compartment TMDD model with two receptors. Receptor complex M1 was formed when compound 1 bound to ASGPR. Receptor complex M2 was formed on deglycosylated IgA bound to receptor complex M2.

[0537] The pharmacokinetic properties of compound 1 were characterized using a population pharmacokinetic approach with data collected in cynomolgus monkeys. The cynomolgus monkey population pharmacokinetic model was developed as a one-compartment model using a simplified TMDD model in which the entire receptor population is kept constant. Predictions of human compound 1 pharmacokinetics were achieved using allometry and scaling of the TMDD model in cynomolgus monkeys. Following preclinical data modeling, translational simulations were performed to quantify both Tc and Tab of compound 1, as well as Gd-IgA1 levels after single-dose and weekly (Q1W) administration across a range of compound 1 doses.

[0538] A starting dose of 125 mg intravenously of compound 1 was selected to maximize participant safety and support the full dose range for safety evaluation, pharmacokinetic, and pharmacodynamic analysis. This dose is less than 1 / 45th of the human equivalent dose of the NOAEL in preclinical toxicology.

[0539] The predicted AUCinf for a single 125 mg intravenous administration in a 70 kg human is 139 μg*h / mL for Tc and 858 μg*h / mL for Tab. Both methods have a predicted initial concentration (C0) of 125 μg / mL. These predicted exposure levels show a margin of at least 70 times the AUC and 56 times the standard deviation for Cmax compared to observed values ​​at NOAEL in both preclinical species. Furthermore, the planned maximum dose (500 mg) is predicted to result in exposure well below the toxic limit of NOAEL (≥13 times lower) Biohaven Therapeutics, c / o Biohaven Pharmaceuticals Inc. (BPI), Compound 1 Researcher's Brochure, Version 2.0 (November 19, 2024).

[0540] Pre- and post-administration sample-IgA1 for Gd was collected from subjects. The proposed dose range to be studied will enable robust characterization of the pharmacokinetic / pharmacodynamic profile of compound 1 and inform dose selection for future patient trials. The planned starting dose of 125 mg is Gd-IgA1; however, Gd-IgA1 is a small fraction (<1%) of total functional IgA and does not provide robust Gd-IgA1 reduction.

[0541] Dose escalation scheme: The dose of compound 1 was sequentially escalated cohort by cohort, from a starting dose of 125 mg to a maximum dose of 500 mg in single escalation doses. The dose levels in single escalation doses were 125 mg (cohort 1), max. 250 mg (cohort 2), and max. 500 mg (cohort 3). Lower doses than 125 mg or intermediate doses compared to the dose tested in the previous cohort may be tested in subsequent cohorts, but the dose did not exceed max. 500 mg without adjustment. Multiple doses may be adjusted based on new safety, tolerability, pharmacokinetic, and pharmacodynamic data. Predicted exposure to compound 1 after a single intravenous dose in humans (Tc and Tab). At the maximum planned dose level of 500 mg, the predicted exposure margin is greater than 13-fold based on exposure data in NOAEL.

[0542] Translational model simulations were performed to determine the baseline Gd-IgA1 level in humans after intravenous bolus administration of Gd-IgA1, which was 9,000 ng / mL (60 nM). The elimination rate of Gd-IgA1 was set to a half-life of 5 days, and the human ASGPR liver receptor density was assumed to be 340 nM. Using these assumptions and the planned exposure to compound 1, near-maximal inhibition is predicted with low doses of compound 1. In addition to providing safety and tolerability, the single dose escalation portion of this example includes compound 1 and Gd-IgA1, including the time of Gd-IgA1 return to baseline to inform the administration frequency of compound 1 in subsequent studies.

[0543] Single-dose escalation dose, subcutaneous starting dose, and dose escalation scheme: The single subcutaneous dose of compound 1 evaluated in each cohort did not exceed the dose level considered safe and tolerable when administered intravenously; the subcutaneous dose in the single-dose escalation dose did not exceed a maximum of 500 mg without correction. Subcutaneous bioavailability after subcutaneous injection in preclinical species was lower than that of intravenous administration, ranging from 8.1% to 46.0% in mice and 4.13% to 15.5% in cynomolgus monkeys. Methods: Post-subcutaneous exposure in humans is expected to be lower than that of the same dose administered intravenously, resulting in an even higher exposure margin (>>13 times) at the highest planned clinical dose of 500 mg.

[0544] Multiple Dose Escalation - Starting Dose and Dose Escalation Scheme The proposed starting dose for multiple dose escalation is 125 mg once weekly (Q1W), with 7 days (days 1, 8, and 15) in between doses, administered in three doses. The dose was confirmed based on safety, tolerability, and pharmacokinetic data, as well as pharmacodynamic data, where available, from the first two dose levels of the single dose escalation part.

[0545] The planned doses of 125 mg (Cohort 1), up to 250 mg (Cohort 2), and up to 500 mg (Cohort 3) may be modified based on predicted exposure from new data from single-dose escalation cohorts and previous multi-dose escalation cohorts. Lower or intermediate doses than those tested in previous cohorts may be tested in subsequent cohorts, but the dose did not exceed 500 mg without adjustment. Dosage, dosing frequency, and follow-up period may be modified based on new data. Planned dosing frequency may be modified to bi-weekly dosing based on observed pharmacokinetics or pharmacodynamics from single-dose escalation cohorts and preceding multi-dose escalation cohorts. The total duration of dosing did not exceed 28 days. Human exposure did not exceed NOAEL exposure from a 28-day preclinical toxicology study.

[0546] Based on preclinical models, the predicted steady-state C0 and AUC (Tc and Tab) of compound 1 in humans after intravenous administration of compound 1 at predicted doses are shown. At the highest planned dose level of 500 mg, the safety limit is ≥11 times.

[0547] The main objectives of this study were (1) to evaluate the safety and tolerability of single and multi-dose intravenous administration of compound 1 in the subjects, and (2) to evaluate the safety and tolerability of single-dose subcutaneous administration of compound 1 in the subjects.

[0548] The second objectives of this study were to (1) evaluate the plasma pharmacokinetics of compound 1 after single and multiple intravenous administration in the subjects, (2) evaluate the plasma pharmacokinetics (PK) of compound 1 after a single subcutaneous administration in the subjects, and (3) evaluate the effect of compound 1 on electrocardiogram parameters (QTcF, PR interval, QRS complex, HR, and T wave morphology) after a single intravenous administration in the subjects.

[0549] Other objectives of this study are (1)(2) to evaluate the immunogenicity of compound 1 after single and multiple administrations in subjects, and (3) to evaluate the metabolic profile of compound 1 in plasma.

[0550] The primary endpoint of this study was to assess safety and tolerability by reporting the frequency of adverse events and unique subjects with grade 3 and grade 4 laboratory abnormalities.

[0551] Secondary endpoints of this study were: (1) for the intravenous single-dose escalation cohort: AUCinf, AUC0-t, Cmax, Tmax, T1 / 2, CL, Vd. (2) for the subcutaneous single-dose escalation cohort: AUCinf, AUC0-t, Cmax, Tmax, Tlag, T1 / 2, Vd / F and CL / F. For day 1 in multiple escalation doses: AUC0-168, Cmax, Cmin, Tmax. (3) For day 15 in multiple escalation doses: AUCtau, Cmax ss, Cmin ss, Cav ss, Tmax ss, T1 / 2, C tau, RAAUCtau, RACmax, Vd, ss, CLss, variation ((Cmax ss-Cmin ss) / Cav ss). (4) Cardiac parameters measured by Holter walking monitoring, including (a) ΔHR, ΔQTcF, ΔPR, and ΔQRS; (b) ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS calculated from a mixed model for repeated measures; (c) out-of-category values ​​of HR, QTcF, PR, and QRS; (d) frequency of changes observed under treatment, including T-wave morphology and U-wave presence; (e) ΔΔQTcF calculated from a CR model between plasma concentration and the change from baseline in the QTcF parameter.

[0552] Part 1 - Single dose escalation cohort (intravenous): Six cohorts will be planned for a total of approximately 48 subjects, each at a different dose level.

[0553] The planned dose range is expected to be 125 mg to 500 mg of compound 1 or placebo. The dose may be modified based on new safety and pharmacokinetic data, but should not exceed 500 mg.

[0554] A time-staggered dosing schedule was used for each cohort, including the first two subjects to receive the active drug and the first to receive a placebo. The remaining six subjects were administered at least 48 hours later, after a review of available safety and tolerability data.

[0555] Part 2 - Multiple Dose Escalation Intravenous Cohorts: While multiple dose escalation is underway, medication will be continued in the subsequent single dose escalation panel. The multiple dose escalation portion consists of approximately 5 cohorts (one cohort per dose level) with a total of approximately 40 subjects.

[0556] Participants were randomized within each dose panel on day 1 (3:1) and received compound 1 or the corresponding placebo on days 1, 8, and 15.

[0557] The total of the planned daily dose escalation range is expected to be from 125 mg Q1W to a maximum dose not exceeding 500 mg of compound 1 Q1W. Dosage and dosing frequency may be modified based on new safety and pharmacokinetic data.

[0558] Part 3 – Single-Dose Elevation Cohort (Subcutaneous): Up to three cohorts can be completed for a total of approximately 24 subjects. The first subcutaneous single-dose elevation cohort will begin after the dose to be used has been tested in the intravenous single-dose elevation cohort, and safety, tolerability, and pharmacokinetic data will be available.

[0559] A time-staggered dosing schedule was used for each cohort, including the two sentinel subjects who received the first dose (one active drug and one placebo). The remaining six subjects received their doses at least 48 hours later, after a review of available safety and tolerability data.

[0560] The starting dose of compound 1 was up to 500 mg. Subsequent doses were selected based on new data from intravenous single-dose escalation cohorts, multiple-dose escalation cohorts, and previous subcutaneous cohorts. Predicted exposure at the highest dose did not exceed the NOAEL (No Observed Adverse Effect Level) from animal toxicology studies.

[0561] For Part 1, single-dose escalation (intravenous), a total of up to 21 blood samples were collected for pharmacokinetic analysis on day 1, i.e., before administration, at the end of infusion, 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, and 12 hours after infusion, on day 2 (24 hours after infusion), day 3 (48 hours after infusion), day 4 (72 hours after infusion), and day 5 (96 hours after infusion), as well as on day 10, day 15 ± 1 day, day 30 ± 3 days, and day 45, day 60, day 75, and day 90 ± 5 days.

[0562] For the single-dose escalating dose (subcutaneous) in Part 3, up to 21 blood samples were collected before administration on day 1 for pharmacokinetic analysis. After 30 doses, i.e., at 1, 2, 3, 4, 6, 8, 10, and 12 hours post-administration, day 2 (24 hours post-administration), day 3 (48 hours post-administration), day 4 (72 hours post-administration), and day 5 (96 hours post-administration), as well as day 10, day 15 ± 1, day 30 ± 3, and days 45, 60, 75, and 90 ± 5.

[0563] Pharmacodynamic blood samples for the following tests were collected at the following time points: (1) Total IgA: Day 1 (before administration), Day 3 (72 hours after administration), Day 5 (96 hours after administration), Day 10, Day 15 ± 1 day, and Day 30 ± 3 days. (2) Gd-IgA1: Day 1, before administration, 4 and 8 hours after administration, Day 2 (24 hours after administration), Day 3 (48 hours after administration), Day 4 (72 hours after administration), Day 5 (96 hours after administration), Day 10, Day 15 ± 1 day, Day 30 ± 3 days, and Day 45, Day 60, Day 75, and Day 90 ± 5 days. (3) Total IgE, Total IgG, Total IgM: Day 1 (before administration), Day 3 (72 hours after administration), Day 5 (96 hours after administration), Day 10, Day 15 ± 1 day, and Day 30 ± 3 days. (4) Circulating immune complex C3: Before administration and 4 hours after administration on day 1, day 2 (24 hours after administration), day 3 (48 hours after administration), day 4 (72 hours after administration), day 5 (96 hours after administration), day 10, and day 15 ± 1. (5) Bank serum: Day 1 (before administration), day 2 (24 hours after administration), day 3 (48 hours after administration), day 4 (72 hours after administration), day 5 (96 hours after administration), day 10, day 15 ± 1, day 30 ± 3, and day 45, day 60, day 75, and day 90 ± 5.

[0564] Samples for anti-drug antibodies were collected on day -1 and day 30±3.

[0565] 12-lead safety electrocardiograms were collected on day -1, day 1 (before administration, 1.5 hours and 6 hours after administration), day 2 (24 hours after administration), day 3 (48 hours after administration), day 4 (72 hours after administration), and day 5 (96 hours after administration). For eligibility purposes (day -1 and day 1 before administration), abnormal values ​​may be verified with two replicates so that triple repeated values ​​are present.

[0566] Holter electrocardiogram monitoring was performed using the Part 1 single dose escalation (intravenous) administered on day 1, and was continued for approximately 25 hours from the start of the treatment.

[0567] Standard biochemistry (HbA1c on the screening day), hematology, and urinalysis tests were performed on days 1, 2, 4, 5, 10, 15 ± 1 day, 30 ± 3 days, and 45, 60, 75, and 90 ± 5 days. Serological chemistry tests were performed after at least 8 hours of fasting; however, in cases of interruption or retesting, subjects may not have fasted for 8 hours prior to the collection of serum chemistry samples.

[0568] Up to 36 blood samples were collected on days 1 and 15 for pharmacokinetic analysis, pre-administration, at the end of infusion, and at 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 6 hours, 8 hours, 12 hours, 13 hours, 48 ​​hours, 72 hours, and 96 hours post-infusion. A single sample was collected on day 8 (pre-administration) and the morning of day 9. Additional pharmacokinetic samples were collected on days 24, 30 ± 1 day, and 60, 75, 90, and 105 ± 5 days.

[0569] Pharmacodynamic blood samples for the following tests were collected at the following time points: (1) Total IgA: Pre-administration on the screening day, day 1, day 8, day 15, day 19, and day 30 ± 1. (2) Gd-IgA1 on day 1 (pre-administration, 4 hours after administration, and 8 hours after administration), day 2 (24 hours after administration), day 4, day 8 (pre-administration), day 12, day 15 (pre-administration), day 19, day 24, day 30 ± 1, day 45 ± 3, and day 75 and day 105 ± 5. (3) Pre-administration total IgE, total IgG, and total IgM on day 1, day 8, day 15, day 19, and day 30 ± 1. (4) Circulating immune complex C3: Day 1 (pre-administration), day 2, day 8 (pre-administration), day 9, day 15 (pre-administration), day 16, and day 19. (5) Serum was stored on day 1 (before administration), day 2, day 3, day 4, day 5, day 6, day 7, day 8 (before administration), day 9, day 10, day 11, day 12, day 13, day 14, day 15 (before administration), day 16, day 17, day 18, day 19, day 24, day 30 ± 1 day, and on day 60 and day 105 ± 5 days.

[0570] 12-lead safety electrocardiograms were collected on day -1, day 1, day 8, and day 15, before administration, and 1.5 hours, 6 hours, 24 hours, 48 ​​hours, and 72 hours after administration, as well as on day 19 and day 24. For eligibility purposes (day -1 and day 1 before administration), abnormal values ​​may be verified with two replicates so that triple repeated values ​​are present.

[0571] Standard biochemistry (HbA1c on the screening day), hematology, and urinalysis tests were performed on days 1, 2, 4, 7, 9, 11, 14, 16, 19, 24, 30, and 45 ± 1 day, as well as on days 60, 75, 90, and 105 ± 2 days. Serological chemistry tests were performed after at least 8 hours of fasting.

[0572] The estimated glomerular filtration rate (GFL) was calculated using the CKD-EPI formula. See CKD-EPI Creatine Equation - National Kidney Foundation (2021). Estimated glomerular filtration rate = 142 x min (Scr / κ,1)α x max (Scr / κ,1)-1.209 x 0.9938 age x 1.012 for females. Scr is serum creatinine (mg / dL), κ is 0.7 for females and 0.9 for males, α = -0.241 (females) or -0.302 (males), min represents the minimum value of Scr / κ or 1, and max represents the maximum value of Scr / κ or 1.

[0573] Pharmacokinetic (PK) sample collection and processing: Plasma concentrations of the study drug were determined using effective analytical methods.

[0574] The collection and processing of pharmacodynamic (PD) blood samples included multiple elevation dose portions, evaluation for Gd-IgA1, total IgA, total IgE, total IgG, total IgM, circulating immune complex C3, and anti-drug antibodies, collected for the following pharmacodynamic analyses. Samples stored in the bank may be analyzed at a later date for plasma proteins, further pharmacokinetic measurements, inflammatory markers, antibodies, immunogenicity, hypersensitivity markers, metabolites, lipids, electrolytes, and hormones.

[0575] Compound 1 formulation (DP) is colorless to slightly yellow, clear to slightly milky white, and essentially free of visible particles. Each vial contains an extractable volume of 2 mL (100 mg). The corresponding placebo for Compound 1 is 0.9% physiological saline, a homogeneous, clear, colorless liquid. Method of treatment assignment / randomization

[0576] Part 1 eligible subjects were randomized on day 1 to receive either active compound 1 or placebo. In each single-dose escalating intravenous cohort, the sentinel subject was randomized to receive one active compound and one placebo, while the remaining subjects were randomized to receive five active compounds and one placebo. In total, approximately six subjects received compound 1 and two subjects received placebo.

[0577] Part 2 eligible subjects were randomized on day 1 to receive either active compound 1 or placebo in a 3:1 ratio. In each multi-dose escalation cohort, approximately 6 subjects received compound 1 and 2 subjects received placebo.

[0578] Part 3 eligible subjects were randomized on day 1 to receive either active compound 1 or placebo. Sentinel subjects were randomized to receive one active compound and one placebo, while the remaining subjects were randomized to receive five active compounds and one placebo. In total, each single-dose escalating subcutaneous cohort consisted of approximately six subjects receiving compound 1 and two subjects receiving placebo.

[0579] A randomization scheme was created for each cohort.

[0580] After completing the trial screening evaluation, all subjects who met all eligibility criteria were assigned a unique identification number, distinct from their screening number, based on their initial randomization code. Once a randomization number is assigned, it cannot be reassigned.

[0581] Investigational drug administration—intravenous compound 1 and placebo were administered via a syringe intravenous pump. The syringe intravenous pump should be programmed immediately before each administration, and a second staff member should verify that the correct settings are programmed by comparing them with the Pharmacy Manual.

[0582] Syringe infusion was performed. The infusion start and end times were recorded. All post-dosage study procedures were scheduled based on the end of the infusion time. For detailed preparation and administration procedures, please refer to the Pharmacy Manual.

[0583] The study drug was administered subcutaneously into the abdomen using either subcutaneous compound 1 or placebo. The maximum dose volume administered was 2 mL per syringe; therefore, doses exceeding 100 mg were administered in multiple injections. For detailed preparation and administration procedures, refer to the Pharmacy Manual.

[0584] The Holter electrocardiogram population includes subjects of the single-dose escalating portion of the study who received compound 1 or placebo intravenously, all of whom had baseline electrocardiogram measurements, as well as subjects during treatment who had at least one post-dosage time point with an effective Holter monitor.

[0585] The pharmacokinetic / Holter ECG population is a population that includes all subjects in Holter and has at least one pair of post-administration pharmacokinetic concentration and ΔQTcF data, as well as the ECG placebo population derived from subjects in Holter at the same time point.

[0586] The following parameters were calculated for the plasma concentration of compound 1 from the single-dose escalation cohort: AUCinf, AUC0-t, inf (percentage of AUC extrapolated beyond the last measurable concentration), dose-normalized AUC0-t, dose-normalized AUCinfCL (CL / F for subcutaneous cohorts), Cmax, dose-normalized Cmax, T1 / 2, Tmax, Tlag (for subcutaneous cohorts), and Vd (Vd / F for subcutaneous cohorts).

[0587] Multiple dose-escalation pharmacokinetic parameters The following pharmacokinetic parameters were calculated for the plasma concentration of compound 1 from multiple dose-escalation cohorts. For day 1 in multiple dose-escalation groups: (1) AUC0-168, (2) Cmax, (3) Cmin, (4) Tmax For day 15 in multiple dose-escalation groups: (1) AUC0-t, (2) AUCtau, (3) Cavg ss, (4) CLss, (5) Cmax ss, (6) Cmin ss, (7) Ctau, (8) Ffuctuation (Cmax ss - Cmin ss) / Cav ss), (9) RAAUCtau, (10) RACmax, (11) T1 / 2, (12) Tmax ss, (13) Vd,ss.

[0588] Pharmacokinetic statistical analysis was performed using Phoenix® and WinNonlin®. Inferential statistical analysis was performed using SAS®. Individual and mean plasma concentration-versus-time curves are shown for both linear and semi-logarithmic scales. Descriptive statistics for plasma concentration-versus-time are presented appropriately for pharmacokinetic parameters by dose / dosage type and day. Concentration exposure is shown graphically for the study portion, dose / dosage type, and / or study day. AUC0-t AUCinf and Cmax for single escalating doses, as well as AUCtau, Cmax ss and Ctau at day 15 for multiple escalating doses, were compared separately by dosing type using a logarithmic power model.

[0589] Cardiac dynamic electrocardiogram endpoints. The electrocardiogram endpoints are: (1) Changes from baseline in HR, QTcF, PR, and QRS (ΔHR, ΔQTcF, ΔPR, and ΔQRS); (2) Placebo-adjusted ΔHR, ΔQTcF, ΔPR, and ΔQRS (ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS); (3) Classification outliers of HR, QTcF, PR, and QRS; (4) Frequency of changes observed due to treatment of T-wave morphology and U-wave presence; (5) Placebo-adjusted baseline-adjusted QTcF (ΔΔQTcF) calculated from concentration - (CR) model between plasma concentration and change from baseline in QTcF parameters.

[0590] Cardiac Dynamics ECG Baseline: For all continuous electrocardiogram parameters, baseline is the mean of the electrocardiogram intervals measured from three pre-administration time points on day 1. For T-wave morphology and the presence of U waves, baseline includes the results observed in any of the repetitions from three pre-administration time points on day 1.

[0591] For concentration-QTc analysis in single-dose escalating intravenous cohorts, the relationship between plasma concentration of compound 1 and ΔQTcF was quantified using a linear mixed-effects modeling approach, with ΔQTcF as the dependent variable, drug plasma concentration (0 for placebo) as the independent variable, central baseline QTcF (i.e., baseline QTcF for individual subjects minus the population-mean baseline QTcF for all subjects) and test treatment (activity=1 or placebo=0) as additional covariates, and time (i.e., a time point after baseline) as a fixed effect. Subject-specific random effects were included in the intercept and slope using an unstructured covariance matrix. Where the unstructured covariance matrix was not supported by the data, other simplified or reduced structures, e.g., variance components, were investigated.

[0592] The degrees of freedom were estimated using the Kenward-Roger method (Kenward & Roger, Biometrics, 53, 983-997 (1997)). From the model, the gradient, i.e., the regression parameter of concentration, and the therapeutic effect-ratio intercept (defined as the difference between the active substance and placebo) were estimated. The time effect was estimated along with a two-sided 95% confidence interval.

[0593] The geometric mean of the individual Cmax values ​​for each dose of the active drug and each day was determined. The predicted effect for ΔΔQTcF and its two-sided 90% confidence interval, i.e., slope estimate at this geometric mean Cmax × geometric mean Cmax + treatment effect-specific intercept, were obtained.

[0594] The validity of the model fit to the linearity assumption and its impact on the quantification of the concentration-response relationship were evaluated using plots of relevant mean placebo-adjusted ΔQTcF (i.e., ΔΔQTcF) with 90% confidence intervals adjusted for the daytime effect, along with a regression line showing the observed median quantile concentration of compound 1 and the predicted ΔΔQTcF. The observed ΔQTcF values ​​from the active group were adjusted for the estimated time effect from the concentration-adjusted QT interval model, i.e., the estimated daytime effect under placebo treatment. For the evaluation of HR-adjusted QT intervals, scatter plots and quantile plots of QTcF and respiratory rate intervals processed by regression lines and linear mixtures (90% confidence intervals) are also shown, respectively. Additional exploratory analyses (by graphical representation and / or model fitting) include explaining delayed effects (hysteresis) and justification of the pharmacodynamic model selection (linear vs. nonlinear). Example 4 Subcutaneous administration of compound 3, an IgG4 degrader, results in potent IgG4 depletion and high subcutaneous bioavailability in mice.

[0595] Compound 3 is a heterobifunctional molecule comprising an anti-IgG 4 nanobody and an ASGPR ligand for the therapeutic use of IgG 4-AID. Compound 3 specifically targets circulating IgG4 and redirects it to the liver for ASGPR-dependent lysosomal degradation in hepatocytes. For further details on Compound 3, please refer to international patent application PCT / IB2025 / 050867.

[0596] This example illustrates a series of pharmacological studies conducted to evaluate compound 3 in an in vivo mouse model.

[0597] Of the four optimized anti-IgG 4-degraders, one form of compound 3 was selected as the primary candidate for a self-injectable device. [Table 3]

[0598] The objective of this example was to determine the potential toxicity of compound 3 when administered to nude mice as a single intravenous bolus injection at a dose of 100 mg / kg, and to evaluate the pharmacokinetic profile and pharmacodynamic effects of compound 3 when administered as an intravenous bolus or subcutaneous injection to exogenously administered human IgG4 in nude mice.

[0599] Identification of test substances and vehicles used in tolerability, pharmacodynamics, and pharmacokinetic studies.

[0600] Phosphate-buffered saline (PBS) pH 7.4 (1×) is commercially available from Gibco. [Table 4]

[0601] On day 0 of the pharmacodynamic study, mice were weighed and randomized. All groups of mice received intravenous hIgG4 15 minutes prior to their treatment (intravenous or subcutaneous injection of compound 3 at 0.77 mg / kg). Compound 3 was administered in a molar ratio of 4:1 (compound 3:IgG4). After an established period, blood was collected from three animals per administration route at two time points. At one time point, 100 μl of blood was collected using the submandibular vein. The same mice were asphyxiated via CO2-induced bleeding for a second blood collection at a later time point. Blood from individual animals was collected in K3E tubes and plasma was separated. All samples were stored at -80°C until evaluation. [Table 5] [Table 6]

[0602] Assay Method for Measuring Plasma Concentration of hIgG4 Anti-Dsg 3 IgG4 concentration was measured using a streptavidin plate (catalog number: L15SA-1-Meso Scale Discovery) according to the manufacturer's instructions. Briefly, the plate was blocked with MSD blocking buffer A for 1 hour. After washing three times with MSD washing buffer (0.05% Tween-20 in phosphate-buffered saline), the plate was coated with biotinylated anti-IgG 4 antibody (catalog number: 3854-6-250-Mabtech) for 1 hour. The plate was washed three times again with MSD washing buffer, and plasma samples (diluted to 1:1000) and standards were added to the plate (1 hour). After incubation, the samples were removed, and the plate was washed three times with MSD washing buffer. Next, detection antibodies (human-non-human primate kappa detection antibody - catalog number D20TF-6 and human-non-human primate lambda detection antibody - catalog number D20QG-6 MSD) were added and incubated for 1 hour. After removing the detection antibodies, the plate was washed three more times with MSD washing buffer. MSD reading buffer was added and the plate was read using an MSD reader.

[0603] All incubation processes were carried out at room temperature with shaking at 700 rpm.

[0604] Standard curves were generated using the same hIgG4 used in the in vivo portion of the study, and serially diluted to cover a range of values ​​(49 pg / ml to 200,000 pg / ml). The raw values ​​were then fitted to a four-parameter logistic (4PL) curve to interpolate the hIgG4 concentrations in the samples.

[0605] Assay Method for Measuring Plasma Concentration of Compound 3 The concentration of Compound 3 was measured using a streptavidin plate (catalog number: L15SA-1-Meso Scale Discovery) according to the manufacturer's instructions. Briefly, the plate was blocked with MSD blocking buffer A for 1 hour. After washing three times with MSD washing buffer, the plate was coated with monoclonal anti-VHH biotinylated antibody (catalog number: A01995-Genscript) for 1.5 hours. After incubation, the plate was washed three times with MSD washing buffer, and plasma samples (diluted to 1:1000) and standards were added to the plate (for 2 hours). (The samples were removed, and the plate was washed three times with MSD washing buffer.) The detection antibody was labeled using anti-VHH cocktail antibody catalog number A02014, then Genscript® was added, and incubated for 1 hour. After removing the detection antibody, the plate was washed three times with MSD washing buffer. MSD reading buffer was added, and the plate was read using an MSD reader.

[0606] A calibration curve was created using compound 3, and serial dilutions were performed to cover a range of values ​​(0 ng / ml to 100 ng / ml). The raw values ​​were then fitted to a 4-parameter logistic (4PL) curve, and the concentration of compound 3 in the sample (ng / ml) was interpolated.

[0607] All incubation processes were carried out at room temperature with shaking at 700 rpm.

[0608] Compound 3 was well tolerated at a dose of 100 mg / kg.

[0609] Mice administered with compound 3 at 50 or 100 mg / kg showed no signs of toxicity or behavioral changes compared to untreated mice.

[0610] Compound 3, administered intravenously or subcutaneously, significantly depleted hIgG4 levels. Exogenously administered plasma hIgG4 antibodies were measured at 0, 0.08, 0.25, 1 / 2, 1, 2, 8, 24, 48, 72, and 96 hours. In the control group, hIgG4 levels remained stable over 96 hours, with only the expected slight decrease.

[0611] Figure 23 is a line graph showing that compound 3 reduces circulating IgG4 in nude mice. Mice administered compound 3 (intravenously or subcutaneously) 15 minutes after hIgG4 showed significant hIgG4 depletion compared to control mice given hIgG4 alone.

[0612] Figure 24 is a bar graph showing that compound 3 reduces circulating IgG4 in nude mice. Further quantification of hIgG4 reduction as the area under the curve showed that intravenous and subcutaneous administration of compound 3 depleted 71% and 87.3% of hIgG4 compared to the control group. Each data point represents the mean hIgG4 plasma concentration at the indicated time point (n=3 per time point). Error bars represent the standard deviation of the mean. Each bar represents the mean AUC of hIgG4 over 96 hours. Error bars represent the standard error of the mean. Statistical significance was calculated by performing a one-way ANOVA.

[0613] Pharmacokinetics of Compound 3

[0614] Figure 25 is a line graph showing the pharmacokinetics of compound 3. Compound 3 (intravenously and subcutaneously) was detected in plasma up to 2 hours after injection.

[0615] Figure 26 is a line graph showing the pharmacokinetics of compound 3. Subcutaneous bioavailability was calculated using the formula: F = AUC subcutaneous (2 hours) / AUC intravenously (2 hours), with F = 71%.

[0616] Each data point represents the mean value of compound 3 in plasma (n=3 per time point). Error bars represent the standard deviation of the mean. (B) Each bar represents the mean AUC of compound 3 (intravenous and subcutaneous) over 2 hours. Error bars represent the standard error of the mean.

[0617] In conclusion, the objective of this example was to characterize the properties of compound 3 in an in vivo mouse model. Compound 3 was found to be well tolerated at the tested dose (approximately 100 mg / kg). Compound 3 mediated a strong reduction in hIgG4 concentration. A single intravenous injection of compound 3 reduced exogenous hIgG4 by 71%, while subcutaneous administration resulted in an 87.3% reduction. Pharmacokinetic studies showed that compound 3 had a subcutaneous bioavailability of 71%. The results of this example indicate that compound 3 targets IgG4 and can promote its clearance in mice, consistent with its mechanism of action. Example 5 Compound 2 (β1 AR autoantibody degrader) for the treatment of cardiomyopathy Single dose escalation (SAD) / Multiple dose escalation (MAD)

[0618] Randomized, placebo-controlled single-dose and multi-dose escalation studies to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of Compound 2 in adults. Compound 2 injections, provided at 50 mg / mL, were administered via in-situ prepared intravenous (IV) infusion or subcutaneous (SC) administration. The corresponding placebo for Compound 2 was 0.9% saline.

[0619] Subcutaneous administration of compound 2 was assayed in mice. Compound 2 is nearly 100% bioavailable subcutaneously in mice. At lower doses (0.2 mpk), Cmax was immediate. Formulations that were not immediate at a 2 mpk dose were sampled at 5, 15, 30, 1, 2, 4, 8, and 24 hours in phosphate-buffered saline. Tmax was 15 minutes for a 2 mg / kg dose.

[0620] This example discloses a randomized, open-label, placebo-controlled, sequential single-dose / multiple-dose escalation trial in the subjects. The parts are: (1) Part 1 - single-dose escalation cohort (intravenous administration); (2) Part 2 - multiple escalation cohorts (intravenous administration) administered weekly at a total of 3 doses / cohort; (3) Part 3 - single-dose escalation cohort (subcutaneous administration); (4) Part 4 - multiple escalation cohorts (subcutaneous administration) administered weekly at a total of 3 doses / cohort.

[0621] Part 1 involves a single escalating dose intravenously. Part 1 includes a single escalating dose of Compound 2 in up to four cohorts (one cohort per dose level). Each single escalating dose cohort includes approximately eight subjects (six subjects receiving the active substance and two subjects receiving placebo, for a total of approximately 32 subjects).

[0622] A time-staggered dosing schedule was used for each cohort. The schedule included two surveillance subjects who received the first dose (one with the active drug and one with a placebo). The remaining six subjects (five with the active drug and one with a placebo) were administered after reviewing the available safety and tolerability data from the two surveillance subjects for at least 24 hours.

[0623] The planned single dose escalation range is expected to be a single intravenous administration of 100 mg to 500 mg of compound 2. Predicted exposure at the highest dose is not expected to exceed NOAELs from animal toxicology studies.

[0624] Part 2: Multiple Elevated Intravenous Administration The multiple escalated dose part consists of up to six cohorts (one cohort per dose level), including multiple escalated intravenous administrations (Part 2) and multiple escalated subcutaneous administrations (Part 4). Each cohort includes approximately 8 subjects out of a total of approximately 48 subjects (6 subjects receiving the active substance and 2 subjects receiving a placebo).

[0625] In this embodiment's design, which includes evaluation at a single dose level before initiating with multiple doses, a single escalating dose cohort functions similarly to that of a sentinel subject for a multiple escalating dose cohort. Based on simulated human pharmacokinetics and ASGPR-mediated clearance of compound 2, the minimum accumulation of compound 2 in plasma is expected with multiple doses.

[0626] The planned total daily dose in the multiple dose-escalation portion of the study is expected to range from 100 mg to a maximum dose not exceeding compound 2 Q1W of 500 mg. Dosage and dosing frequency may be modified based on new safety and pharmacokinetic data. Planned exposure at the highest dose tested did not exceed NOAEL in rats.

[0627] Part 3: Single-dose escalating subcutaneous administration. Up to two cohorts may be completed. Each cohort will consist of approximately 16 subjects in total, with approximately 8 subjects (6 receiving the active substance and 2 receiving placebo). The first subcutaneous single-dose escalating cohort will be initiated after the dose to be used has been tested in the intravenous single-dose escalating cohort.

[0628] A time-staggered dosing schedule was used for each cohort. Two sentinel subjects (one receiving the active drug and one receiving placebo) were administered first. The remaining six subjects (five receiving the active drug and one receiving placebo) were administered after reviewing available safety and tolerability data from two surveillance subjects for at least 24 hours.

[0629] Part 4: Multiple Elevated Subcutaneous Administration The Multiple Elevated Part consists of up to six cohorts (one cohort per dose level), including multiple escalating intravenous administrations (Part 2) and multiple escalating subcutaneous administrations (Part 4).

[0630] The planned total daily dose in the subcutaneous portion of the multiple-dose escalation regimen in the examples did not exceed 500 mg of compound 2 Q1W. Dosage, frequency of administration, and follow-up period may be modified based on new data. The planned dosing frequency may be modified to bi-weekly dosing based on the pharmacokinetics observed from the single-dose escalation cohort and the preceding multiple-dose escalation cohort.

[0631] The primary objectives for the single dose escalation studies were (1) to characterize the safety and tolerability of a single dose intravenous administration of compound 2 in the subjects, and (2) to characterize the safety and tolerability of a single dose subcutaneous administration of compound 2 in the subjects. The secondary objectives were (1) to characterize the plasma pharmacokinetics (PK) of a single dose intravenous administration of compound 2 in the subjects, (2) to characterize the plasma pharmacokinetics of a single dose subcutaneous administration of compound 2 in the subjects, and (3) to characterize the effect of compound 2 on electrocardiogram (ECG) parameters (QTcF, PR interval, QRS complex, HR, and T wave morphology) after a single dose intravenous administration of compound 2. Other objectives were (1) to characterize the metabolic profile of compound 2 in plasma, (2) to characterize the pharmacodynamic (PD) effect of compound 2 after a single dose in the subjects, and (3) to characterize the immunogenicity of compound 2 after a single dose in the subjects. The primary objectives of the multiple dose escalation studies were (1) to characterize the safety and tolerability of multiple doses of compound 2 administered intravenously in the subjects, and (2) to characterize the safety and tolerability of multiple doses of compound 2 administered subcutaneously in the subjects. The second objectives were (1) to characterize the plasma pharmacokinetics of compound 2 after multiple doses of intravenous administration in the subjects, and (2) to characterize the plasma pharmacokinetics of compound 2 after multiple subcutaneous BHV1600 administrations in the subjects. Other objectives included (1) to characterize the pharmacodynamic effects of compound 2 after multiple doses in the subjects, (2) to characterize the immunogenicity of compound 2 after multiple doses in the subjects, and (3) to characterize the urinary pharmacokinetics of BHV1600 after multiple doses of intravenous and subcutaneous administration of compound 2 in the subjects.

[0632] For single-dose escalation cohorts, the primary endpoint was to assess safety and tolerability by reporting the frequency of unique subjects with serious adverse events and grade 3-4 (CTCAE / DAIDS) laboratory abnormalities. Secondary endpoints were: (1) For the intravenous single-dose escalation cohort (Part 1): AUC0-t, AUCinf, AUC0-168, Cmax, Tmax, T1 / 2, CL, Vd, and Tlast of compound 2 after single administration. (2) For the subcutaneous single-dose escalation cohort (Part 3): AUCinf, AUC0-t, Cmax, Tmax, Tlag, T1 / 2, Vd / F, and CL / F were calculated. (3) For the single-dose escalation cohort (intravenous) in Part 1: (a) cardiac parameters measured by Holter walking monitoring, including changes from baseline in HR, QTcF, PR, and QRS (ΔHR, ΔQTcF, ΔPR, and ΔQRS). (b) Placebo-corrected ΔHR, ΔQTcF, ΔPR, and ΔQRS (ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS) calculated from a mixed model for repeated measures. (c) Classification outliers of HR, QTcF, PR, and QRS. (d) Frequency of changes observed due to treatment of T-wave morphology and U-wave presence. (f) Placebo-corrected baseline-adjusted QTcF (ΔΔQTcF) calculated from a concentration-response (CR) model between plasma concentration and changes from baseline in the QTcF parameter.

[0633] For multiple dose escalations, the primary endpoint was to assess safety and tolerability by reporting the frequency of SAEs, severe AEs, AEs leading to discontinuation, death, and unique subjects with grade 3-4 (CTCAE / DAIDS) laboratory abnormalities. Secondary endpoints were: (1) Day 1 for the intravenous cohort (Part 2) and subcutaneous cohort (Part 4): AUC0-t, AUC0-168, Cmin, Cmax, Tmax; (2) Day 15 (stable state) for the intravenous cohort (Part 2): AUCtau, Ctau, Cmax ss, Tmax, T1 / 2, RAAUCtau, RACmax, Vdss, CLss; (3) Day 15 (steady state) for the subcutaneous cohort (Part 4): AUCtau, Ctau, Cmax ss, Tmax, T1 / 2, RAAUCtau, RACmax, Vdss / F, CLss / F.

[0634] For Holter electrocardiogram Part 1 single-dose escalating intravenous administration (sequential electrocardiogram recording Holter monitoring in a single-dose escalating cohort), calculations from Holter electrocardiogram data were completed for the following: (1) Changes from baseline in HR, QTcF, PR, and QRS (ΔHR, ΔQTcF, ΔPR, and ΔQRS); (2) Placebo-corrected ΔHR, ΔQTcF, ΔPR, and ΔQRS calculated from a mixed model for repeated measures (ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS); (3) Classification outliers of HR, QTcF, PR, and QRS; (4) Frequency of changes observed due to treatment of T-wave morphology and U-wave presence; (5) Placebo-corrected baseline-adjusted QTcF (ΔΔQTcF) calculated from a concentration-response (CR) model between plasma concentration and changes from baseline in QTcF parameters.

[0635] Analysis of ECG records was based on concentration-QTc modeling of the relationship between compound 2 and the change from baseline (ΔQTcF) at observed compound 2 plasma concentrations, with the intention of eliminating the placebo-corrected ΔQTcF (ΔΔQTcF) > 10 msec effect.

[0636] Pharmacokinetics. Individual and mean plasma concentration-versus-time curves are presented for both linear and semi-logarithmic scales. Summary statistics are used to describe the plasma concentration and pharmacokinetic parameters of compound 2 for each dose level / dosage type.

[0637] The power generation that was approached was converted

[0638] For single-dose and multi-dose escalations, AUC0-t, AUC0-inf, and Cmax are measured on day 1.

[0639] Multiple dose escalation parameters, day 15 AUCtau, Cmax ss, Ctau, and AUC0-t, were used to evaluate dose-proportionality for intravenous and, where applicable, subcutaneous administration.

[0640] Compound 2 is a bifunctional extracellular proteolytic agent designed to selectively bind to circulating anti-β1 adrenergic receptor (β1 AR) autoantibodies and redirect them to the liver for asial glycoprotein receptor (ASGPR)-mediated endolysosomal degradation. It consists of three parts: a peptide mimicking the second extracellular loop of β1 AR, an ASGPR conjugate, and a polyethylene glycol (PEG) linker.

[0641] Clinical evidence supporting the rationale for the removal of autoantibodies in dilated cardiomyopathy is supported by studies reporting improved outcomes in dilated cardiomyopathy after immunoadsorption IA therapy. See Dungen et al., Circ., 13(1), e006155(2020).

[0642] Immunoadsorption studies have consistently demonstrated that removal of all IgG, or selective removal of IgG3 subclasses, is associated with improved cardiac function, increased mean left ventricular ejection fraction, or delayed time to or need for heart transplantation. Dandel (Barton) et al., Eur. J. Heart Fail., 14(12), 1374-88 (2012); Muller et al., Circulation, 101(4), 385-91 (2000); Felix et al., J. Am. Coll., 35(6), 1590-8 (2000); and Schimke et al. Apher., 20(3), 137-42 (2005).

[0643] The reappearance of β1 AR-specific autoantibodies after immunoadsorption correlated with deterioration of cardiac function. Magnusson et al., Circulation, 89(6), 2760-7.

[0644] Guideline-directed medical therapy (GDMT) for heart failure in this population utilizes the same supportive care used for heart failure with reduced ejection fraction, i.e., a condition affecting different demographics with significantly different etiologies. Current GDMT does not address the autoimmune underlying pathophysiology of dilated cardiomyopathy; rather, it provides supportive care that attempts to improve the signs and symptoms of the disease without addressing the underlying cause of myocardial dysfunction. Plasma separation and exchange and specific anti-β1 AR autoantibody IA have been used with moderate success in these clinical scenarios. These autoantibody removal approaches have shown both acute and long-term effects on cardiac function and remodeling. Bi An, Wang, and Lee, Medicine (Baltimore), 100(26), e26475 (2021). These therapies are expensive and complex due to the need for vascular access and repeated therapy, making these options demanding and impractical on a large scale. For further information, see COMPOUND 2 Investigator Brochure v1.0. Biohaven, 2024.

[0645] Compound 2 showed low permeability and was not a substrate for human p-glycoprotein (P-gp).

[0646] The plasma pharmacokinetic profile of compound 2 was determined after bolus intravenous or subcutaneous injection in mice, rats, dogs, and cynomolgus monkeys. Clearance was low after intravenous or subcutaneous administration. Bioavailability was >50% in all species.

[0647] In Sprague Dawley rats, after intravenous injection once every other day for at least 4 weeks at dose levels of 50, 150, or 500 mg / kg, or in cynomolgus monkeys, at dose levels of 30, 250 mg / kg, 100, 250 mg / kg, or 250 mg / kg, the increase in Cmax and AUClast was approximately dose-proportional on day 1 and day 29, no sex-related differences were observed, and there was little or no accumulation between day 1 and day 29.

[0648] Summary of the clinical trial. The purpose of this example is to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of compound 2 after administration of single-dose and multiple-dose escalating doses in adult subjects.

[0649] Single-Dose Elevation - Initiation of Dose Selection (Intravenous) The calculation of the intravenous starting dose for the single-dose elevation part (Part 1) is based on the methodology described in the U.S. Food and Drug Administration (FDA) guidance on estimating the maximum safe starting dose in early clinical trials for therapies in healthy adult volunteers, and the European Medicines Agency (EMA) Guideline on Strategies to Identify and Mitigate Risks for First-in-human and Early Clinical Trials with Investigational Medicinal Products.

[0650] The starting human dose of 100 mg of compound 2 intravenously was selected based on a combination of data from nonclinical pharmacological, pharmacokinetic, and toxicological studies, while allowing a safety factor of over 50 to maximize participant safety and support the full dose range for safety assessment and pharmacokinetic analysis purposes. [Table 7]

[0651] In both rats and monkeys, the highest dose tested was NOAEL (500 mg / kg in rats and 250 mg / kg in monkeys), resulting in the same human equivalent dose (HED) of 80.6 mg / kg NOAEL, or a uniform dose of 5645 mg assuming a body weight of 70 kg. The mean sex-total Cmax (2080 μg / mL) and AUCinf (1150 μg*h / mL) in rats at NOAEL were slightly lower than those observed in monkeys, forming the basis for the predicted exposure margin.

[0652] Modeling and translational simulations were performed to support dose selection and dose justification for pharmacokinetic compound 2. The pharmacokinetics of compound 2 were analyzed using data collected in population pharmacokinetic monkeys. A model with three compartmentalized pharmacokinetic linear clearances was fitted to the available monkey data, and human compound 2 was planned using relative growth simulations. Pharmacokinetic linear elimination clearance and distributional clearance were assumed to scale for humans using a standard relative growth index of 0.75. Volume was assumed to scale for humans with a relative growth index of 1. These simulations provided exposure estimates over a range of fixed doses for single doses and Q1W × 3 doses.

[0653] The proposed starting dose of compound 2 is 100 mg intravenously, providing a margin of more than 50 times the human equivalent dose of the 28-day NOAEL in rats and monkeys. The predicted AUCinf and Cmax for a single 100 mg intravenous administration in a 70 kg human are 15.5 μg*h / mL and 22.3 μg / mL, respectively, providing a margin of more than 74 times the 28-day exposure observed in rats at the NOAEL. This starting dose was selected to maximize participant safety and support the full dose range for safety evaluation, pharmacokinetic, and pharmacodynamic analyses. The maximum dose (500 mg) was predicted to result in exposure less than 1 / 15th of the NOAEL toxicity limit in rats.

[0654] Compound 2 dose-dependently degraded exogenously administered mouse anti-β1 AR antibodies in rats upon intravenous administration at doses of 0.05 mg / kg, 0.2 mg / kg, and 1 mg / kg. Mouse data in translating humans are unknown. The proposed dose range informs the safety and tolerability of Compound 2 across a wide range of doses and exposures. Approximately 10% of asymptomatic healthy adults have β1 AR autoantibodies. Becker et al., Autoimmun., 16(3), 269-286 (2017); H. Haghikia et al., Basic Res. Cardiol., 110(6), 60 (2015). Samples to quantify β1 AR autoantibodies were collected from all subjects in the study. Changes in β1 AR autoantibodies were administered to the test drug, and if detected, this would inform dose selection and dosing frequency in future patient populations with reference to Compound 2 exposure.

[0655] Dose escalation scheme (intravenous): The intravenous dose of compound 2 was sequentially escalated cohort by cohort, starting from a single escalation dose of 100 mg. Planned subsequent dose levels in the single escalation dose were 200 mg, 400 mg, and ≤500 mg. Doses could be adjusted based on available safety, tolerability, and pharmacokinetic data from preceding cohorts and did not exceed the dose proposed for that cohort. Dose escalations did not exceed a twofold increase between cohorts. The highest planned dose level of 500 mg predicted single-dose exposure margins of 19 × and 15 ×, respectively, for exposure in rats at 28-day NOAEL. [Table 8]

[0656] Participants in up to four cohorts received the single-dose escalating intravenous portion (Part 1) of this study. The maximum dose of compound 2 administered was not greater than 500 mg. Lower or intermediate doses of compound 2 than those evaluated in previous cohorts could be investigated, but not exceeding 500 mg.

[0657] Subcutaneous doses of Compound 2 (initial dose selection) were sequentially escalated for each cohort. Doses could be adjusted based on available safety, tolerability, and pharmacokinetic data from preceding cohorts and did not exceed the proposed dose for that cohort. The single subcutaneous dose of Compound 2 evaluated in each cohort did not exceed the dose level considered safe and tolerable when administered intravenously. Subcutaneous doses in single escalation doses did not exceed a maximum of 500 mg without correction. Population pharmacokinetic models yielded bioavailability estimates of 67.8%, assuming a relative growth index of -0.25 for the absorption rate constant.

[0658] The highest planned dose level of 500 mg (subcutaneous) in the dose escalation scheme predicted subcutaneous single-dose exposure margins of 196 × and 15 × for Cmax and AUC in rats at 28 days NOAEL. In short, post-subcutaneous exposure in humans is expected to be similar to that of the same intravenously administered dose, unless it is lower. [Table 9]

[0659] Participants in up to two cohorts were administered the single-dose, escalating subcutaneous (Part 3) portion of this study. The maximum dose of compound 2 administered did not exceed 500 mg. Lower or intermediate doses of compound 2 than those assessed in previous cohorts may also be investigated, but not exceeding 500 mg.

[0660] For the multiple escalation dose (Part 2), the proposed starting dose is 100 mg administered intravenously once weekly (Q1W) for three doses with a 7-day rest period between doses (days 1, 8, and 15). This dose was confirmed based on safety, tolerability, and pharmacokinetic data from the first two dose levels of the single escalation dose part.

[0661] The dosing frequency of compound 2 will be determined by pharmacodynamics, e.g., the degree and duration of β1 AR autoantibody suppression. Compound 2 is planned to be administered once weekly in three doses across the multiple dose-escalation portions of this study to inform safety and pharmacokinetics.

[0662] The planned dose escalation scheme (intravenous) of 200 mg, 400 mg, and ≤500 mg may be modified based on predicted exposure from new data from the single-dose escalation cohort and previous multi-dose escalation cohorts. Dosage, dosing frequency, and follow-up period may be changed based on new data. For example, the planned dosing frequency may be modified to bi-weekly dosing based on observed pharmacokinetics from the single-dose escalation cohort and preceding multi-dose escalation cohorts. Dose escalation did not exceed a twofold increase between cohorts.

[0663] Based on the preclinical pharmacokinetic model described above, we provide the predicted steady-state Cmax and AUC of compound 2 in humans after intravenous administration of compound 2 Q1W at predicted doses. The highest planned dose level of 500 mg Q1W predicted steady-state exposure margins of 19x and 15x, respectively, for Cmax and AUC in rats at 28-day NOAEL. [Table 10]

[0664] (Dose Selection and Subcutaneous Dose Escalation) The starting and subsequent subcutaneous doses of compound 2 in multiple escalation doses (Part 4) were selected based on new data from intravenous single-dose and multiple-escalation dose cohorts as well as from previous single-dose subcutaneous cohorts, but did not exceed 500 mg. The proposed dosing frequency for subcutaneous doses is once per week (Q1W) for three doses, with a 7-day rest period between doses (days 1, 8, and 15). The highest planned subcutaneous dosing level of 500 mg Q1W predicted steady-state exposure margins of 196x and 15x for Cmax and AUC in rats at 28-day NOAEL. [Table 11]

[0665] Participants (intravenously and subcutaneously) across a total of six cohorts were administered the multi-dose escalation portion of this study. The maximum dose of compound 2 administered did not exceed 500 mg Q1W. Less frequent dosing schedules (e.g., every two weeks) may be investigated if guaranteed, but no more than three doses of compound 2 were administered over a 28-day period.

[0666] For principle studies of research populations, subjects without associated diseases or medications represent a homogeneous population that allows for appropriate evaluation of drug safety, tolerability, pharmacokinetics, and pharmacodynamic profiles without confounding factors. Approximately 10% of asymptomatic healthy adults have β1 AR autoantibodies. See Becker et al., Autoimmun., 16(3), 269-286 (2017); and Haghikia (Barton) et al., Basic Res. Cardiol., 110(6), 60 (2015).

[0667] Benefit / risk assessment. Non-clinical safety studies support the administration of compound 2 in humans. In non-clinical studies, compound 2 was well tolerated and did not cause adverse effects in animal species at dose levels significantly higher than the proposed human dose.

[0668] Compound 2 was shown to be stable in plasma, and no extracellular free ECL2 peptide was detected. The ternary complex undergoes extensive metabolism in the liver and is therefore unlikely to be immunogenic.

[0669] The primary objectives of the single dose escalation study were: (1) to characterize the safety and tolerability of single-dose intravenous administration of compound 2 in the subjects; and (2) to characterize the safety and tolerability of single-dose subcutaneous administration of compound 2 in the subjects. The secondary objectives of the single dose escalation study were: (1) to characterize the plasma pharmacokinetics of single-dose intravenous administration of compound 2 in the subjects; (2) to characterize the plasma pharmacokinetics of single-dose subcutaneous administration of compound 2 in the subjects; and (3) to characterize the effect of compound 2 on ECG parameters (QTcF, PR interval, QRS complex, HR, and T-wave morphology) after single intravenous administration of compound 2. Other objectives included: (1) to characterize the metabolic profile of compound 2 in plasma; (2) to characterize the pharmacodynamic effects of compound 2 after single administration of compound 2 in the subjects; and (3) to characterize the immunogenicity of compound 2 after single administration of compound 2 in the subjects.

[0670] The primary objectives of the multiple dose escalation studies were: (1) to characterize the safety and tolerability of multiple doses of compound 2 administered intravenously in the subjects; and (2) to characterize the safety and tolerability of multiple doses of compound 2 administered subcutaneously in the subjects. The secondary objectives of the multiple dose escalation studies were: (1) to characterize the plasma pharmacokinetics of compound 2 after multiple doses of compound 2 administered intravenously in healthy subjects; and (2) to characterize the plasma pharmacokinetics of compound 2 after multiple subcutaneous doses in healthy subjects. Other objectives included: (1) to characterize the pharmacodynamic effects of compound 2 after multiple doses in healthy subjects; (2) to characterize the immunogenicity of compound 2 after multiple doses in the subjects; and (3) to characterize the urinary pharmacokinetics of compound 2 after multiple doses of intravenous and subcutaneous administration in the subjects.

[0671] The primary endpoint for the single-dose escalation cohort was to assess safety and tolerability by reporting the frequency of unique subjects with serious adverse events and grade 3-4 (CTCAE / DAIDS) laboratory abnormalities. For the intravenous single-dose escalation cohort (Part 1): Compound 2 AUC0-t, AUCinf, AUC0-168, Cmax, Tmax, T1 / 2, CL, Vd, and Tlast were calculated after single administration. For the subcutaneous single-dose escalation cohort (Part 3): AUCinf, AUC0-t, Cmax, Tmax, Tlag, T1 / 2, Vd / F, and CL / F were calculated.

[0672] For Part 1 (single dose escalating intravenously): Cardiac parameters measured by Holter walking monitoring include: changes from baseline in HR, QTcF, PR, and QRS (ΔHR, ΔQTcF, ΔPR, and ΔQRS); and placebo-corrected ΔHR, ΔQTcF, ΔPR, and ΔQRS calculated from a mixed model for repeated measures (ΔΔHR, ΔΔQTcF, ΔΔPR, and ΔΔQRS).

[0673] Classification outliers of HR, QTcF, PR, and QRS. Frequency of changes observed under treatment for T-wave morphology and U-wave presence.

[0674] Placebo-corrected baseline-adjusted QTcF (ΔΔQTcF) calculated from a concentration-response (CR) model between plasma concentration and the change from baseline in the QTcF parameter.

[0675] For multiple dose escalations, the primary endpoint is to assess safety and tolerability by reporting the frequency of serious adverse events (SAEs), severe AEs, AEs leading to discontinuation, death, and unique subjects with grade 3-4 (CTCAE / DAIDS) laboratory abnormalities. Secondary endpoints are as follows: 1) For the intravenous cohort (Part 2) and subcutaneous cohort (Part 4): Day 1: AUC0-t, AUC0-168, Cmin, Cmax, Tmax. For the intravenous cohort (Part 2), Day 15 (stable): AUCtau, Ctau, Cmax, ss, Tmax, T1 / 2, RAAUCtau, RACmax, Vdss, CLss. (3) For the subcutaneous cohort (part 4), day 15 (stable state): AUCtau, Ctau, Cmax, ss, Tmax, T1 / 2, RAAUCtau, RACmax, Vdss / F, CLss / F.

[0676] Local injection site administration response evaluation. Drug response evaluation was performed at time points for both the single dose escalation portion and the multiple dose escalation portion.

[0677] Continuous ECG (Holter monitoring) - Part 1: Single dose escalating intravenous administration. The subject rested for 15 minutes at each time point during which ECG data was extracted from the continuous Holter recording.

[0678] The glomerular filtration rate (GFL) was calculated using the 2021 CKD-EPI formula. For females, the estimated GFL = 142 x min(Scr / κ,1)α x max(Scr / κ,1)-1.2 x 0.9938 age x 1.012. Scr is serum creatinine (mg / dL), κ is 0.7 for females and 0.9 for males, α = -0.241 (females) or -0.302 (males), min represents the minimum value of Scr / κ, i.e., 1.0, and max represents the maximum value of Scr / κ, i.e., 1.0. See CKD-EPI Creatine Equation - National Kidney Foundation (2021).

[0679] The clinical laboratory assessments performed included anti-drug antibodies; alanine aminotransferase; activated partial thromboplastin time; aspartate aminotransferase; blood urea nitrogen; assays from the Chronic Kidney Disease Epidemiology Collaboration; COVID-19; creatinine phosphokinase; estimated glomerular filtration rate; follicle-stimulating hormone; gamma-glutamyltransferase; glycated hemoglobin test (hemoglobin A1c, HbA1c); hepatitis B surface antigen; hepatitis C virus; high-density lipoprotein cholesterol; human immunodeficiency virus; lactate dehydrogenase; low-density lipoprotein cholesterol; mean corpuscular hemoglobin; mean corpuscular hemoglobin concentration; mean corpuscular volume; pH; prothrombin time; erythrocytes; RBC distribution width; and leukocytes.

[0680] Pharmacokinetic evaluation. Blood samples for pharmacokinetic analysis were collected via intravenous catheter or direct venous puncture. Plasma concentrations of the study drug were determined using effective analytical methods.

[0681] Collection and processing of plasma pharmacokinetic samples. Since the actual post-administration sampling time was used for pharmacokinetic and statistical analysis, pharmacokinetic sample collection outside the predefined time window was not considered a protocol deviation. Remaining or backup plasma samples were stored for potential metabolite analysis and reported separately if analyzed.

[0682] Administration of the study drug—syringe infusion for all intravenous doses and across all cohorts—is described in the Pharmacy Manual. For detailed preparation and administration procedures, refer to the Investigator Brochure and Pharmacy Manual.

[0683] Investigational drug administration - subcutaneous. Compound 2 or placebo was administered subcutaneously at a maximum dose of 2 mL per injection. Refer to the Pharmacy Manual for detailed preparation and administration procedures.

[0684] Potential use of higher subcutaneous volumes. Doses of compound 2 or placebo exceeding 100 mg in subcutaneous cohorts may utilize higher single-dose volumes exceeding 2 mL / injection, and syringe pumps may be used instead of direct injection. Dosage volumes up to 30 mL have been safely used in several other published studies. See Dolton et al., Clin. Pharmacol., 110(5), 1337-1348 (2021); Nagy et al., 44(1), 28 (2023); and Woodley et al., 15(1), 92-104 (2022). Potential use of higher volumes for administration is expected to be well tolerated and safe. For detailed preparation and administration procedures, see the Investigator Brochure and Pharmacy Manual.

[0685] A complete description of the statistical analyses performed regarding safety and tolerable pharmacokinetics, pharmacodynamics, immunogenicity, and Holter ECG data is presented in the Statistical Analysis Plan (SAP).

[0686] The sample size for this embodiment is not determined based on statistical calculations. A sample ...

Claims

1. The desired pharmacodynamic / pharmacokinetic ratio (EC50) is achieved by promoting the reduction of pathogenic protein levels in the target and comprising (i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the target, and (ii) a bifunctional degrader having affinity for pathogenic protein, wherein the AUC measured 7 to 14 days after administration of the desired EC50 is at least 1.0 to 1.8 for monovalent degraders and 1.5 to 3.0 for bivalent degraders.

2. The aforementioned composition is a MoDE degrader.

3. The composition according to claim 1, wherein the composition is a TRAP degrader.

4. A method for treating a disease susceptible to a response by reducing the level of a pathogenic protein, wherein the subject requiring such treatment is given a therapeutically effective amount of i) hepatocyte asialoglycoprotein ASGPR receptor expressed in the liver of the subject, and ii) a degrader having affinity for the pathogenic protein.

5. The method according to claim 4, further comprising assaying the subject to determine whether subcutaneous administration of a degrader favorably reduces the level of pathogenic protein in the subject.

6. The aforementioned decomposing agent has chemical formula (I), (II), or (III): 【Chemistry 1】 【Chemistry 2】 【Transformation 3】 (in chemical formulas (I), (II), (III) R2 is NHC(=O)CH3; R5 is CH2OH; A pathogenic protein targeting ligand is a ligand that has affinity for pathogenic proteins. [Linker A] is a chemical group that links the ASGPR ligand to linker B, Linker C, or linker D; Linker B is a chemical group that links linker A to a pathogenic protein targeting ligand; [LinkerC] is a chemical group that links LinkerC to a pathogenic protein targeting ligand; and Linker D is a chemical group that links Linker A to a pathogenic protein targeting ligand.

7. The method according to claim 4, wherein the decomposing agent has the following general chemical structure: 【Chemistry 4】 In the formula, [CPBM] is a pathogenic protein-binding moiety that binds to a pathogenic form of a pathogenic protein identified herein, which is associated with and / or mediates a pathological state and / or condition and is removed by the action of hepatocytes or other cells. [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via the asialocrycoprotein receptors or other receptors identified herein, which are present on the surface of hepatocytes and other degraded cells. Each [CON] is either directly connected to the [CPBM] or [CRBM] if present, or is any connector chemical part that connects the [LINKER] to the [CPBM] or [CRBM], and [LINKER] is a chemical moiety having a valency of 1 to 15, which is covalently bonded to one or more [CRBM] and / or [CPBM] groups via [CON] which optionally contains a [MULTICON] group, and the [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself. k' is an integer between 1 and 15; j' is an integer between 1 and 15; h and h' are each independent integers between 0 and 15; iL is an integer between 0 and 15; The present invention relates to compounds of (wherein at least one of h, h', and iL is at least 1), or pharmaceutically acceptable salts, stereoisomers, solvates, or polymorphs thereof.

8. The method according to claim 4, wherein the pathogenic protein degrading agent is an immunoglobulin G ("IgG") degrading agent.

9. The method according to claim 4, wherein the pathogenic protein degrading agent is a galactose-deficient immunoglobulin A ("Gd-IgA") degrading agent.

10. The method according to claim 4, wherein the pathogenic protein degrading agent is an anti-β1ECII autoantibody degrading agent.

11. The method according to claim 4, wherein the pathogenic protein degrading agent is an immunoglobulin E ("IgE") degrading agent.

12. The method according to claim 4, wherein the pathogenic protein degrading agent is an immunoglobulin M ("IgM") degrading agent.

13. A method for reducing the level of pathogenic protein in a subject, comprising subcutaneously administering a therapeutically effective amount of a pathogenic protein degrader to the subject.

14. The method according to claim 13, wherein the pathogenic protein degradation agent is an IgG degradation agent.

15. The method according to claim 13, wherein the pathogenic protein degrading agent is a galactose-deficient immunoglobulin A ("Gd-IgA") degrading agent.

16. The method according to claim 13, wherein the pathogenic protein degradation agent is an anti-β1 ECII autoantibody degradation agent.

17. The method according to claim 13, wherein the pathogenic protein degrading agent is an immunoglobulin E ("IgE") degrading agent.

18. The method according to claim 13, wherein the pathogenic protein degrading agent is an immunoglobulin M ("IgM") degrading agent.

19. A method for reducing the level of pathogenic proteins in a subject, comprising contacting a component of the extravascular system of the subject with an amount effective in promoting the reduction of the level of pathogenic proteins in the subject, which includes (i) hepatocyte asialoglycoprotein (ASGPR) receptors expressed in the liver of the subject, and (ii) a degrading agent having affinity for pathogenic proteins.

20. The method according to claim 19, wherein the pathogenic protein mediates a disease selected from cancer, heart disease, autoimmune disease, or inflammatory disease.

21. The method according to claim 19, wherein the pathogenic protein is an abnormal immunoglobulin.

22. The method according to claim 21, wherein the immunoglobulin is immunoglobulin A ("IgA"), immunoglobulin D ("IgD"), immunoglobulin E ("IgE"), immunoglobulin G ("IgG"), or immunoglobulin M ("IgM").

23. The method according to claim 22, wherein the abnormal IgA is galactose-deficient immunoglobulin A ("Gd-IgA").

24. The method according to claim 19, wherein the extravascular system is the lymphatic system.

25. The method according to claim 24, wherein the components of the lymphatic system are lymph, lymphatic vessels, lymph nodes, and lymphatic organs.

26. The method according to claim 19, wherein the decomposing agent has chemical formula (I), (II), or (III): 【Transformation 5】 【Transformation 6】 【Transformation 7】 (in chemical formulas (I), (II), (III) R2 is NHC(=O)CH3; R5 is CH2OH; A pathogenic protein targeting ligand is a ligand that has affinity for pathogenic proteins. [Linker A] is a chemical group that links the ASGPR ligand to linker B, Linker C, or linker D; Linker B is a chemical group that links linker A to a pathogenic protein targeting ligand; [LinkerC] is a chemical group that links LinkerC to a pathogenic protein targeting ligand; and Linker D is a chemical group that links Linker A to a pathogenic protein targeting ligand.

27. The method according to claim 19, wherein the decomposing agent has the following general chemical structure: 【Transformation 8】 [CPBM] is a pathogenic protein-binding moiety that binds to a pathogenic form of a pathogenic protein identified herein, which is associated with and / or mediates a pathological state and / or condition and is removed by the action of hepatocytes or other cells on circulating proteins (the compound preferably selectively binds to IgG in the plasma of the subject or patient); [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via the asialocrycoprotein receptors or other receptors identified herein, which are present on the surface of hepatocytes and other degraded cells. Each [CON] is either directly connected to the [CPBM] or [CRBM] if present, or is any connector chemical part that connects the [LINKER] to the [CPBM] or [CRBM], and [LINKER] is a chemical moiety having a valency of 1 to 15, which is covalently bonded to one or more [CRBM] and / or [CPBM] groups via [CON] which optionally contains a [MULTICON] group, and the [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself. k' is an integer between 1 and 15; j' is an integer between 1 and 15; h and h' are each independent integers between 0 and 15; iL is an integer between 0 and 15; The present invention relates to compounds of (wherein at least one of h, h', and iL is at least 1), or pharmaceutically acceptable salts, stereoisomers, solvates, or polymorphs thereof.

28. The method according to claim 19, wherein the degrader is administered to the subject before it comes into contact with the components of the extravascular system of the subject.

29. The method according to claim 19, wherein the reduction in the level of pathogenic protein in the subject is 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more.

30. The method according to claim 19, wherein the reduction in the level of the pathogenic protein lasts for at least 10 hours, at least 20 hours, at least 30 hours, at least 40 hours, at least 50 hours, at least 60 hours, at least 70 hours, at least 80 hours, at least 90 hours, or at least 100 hours after administration.

31. The method according to claim 19, wherein the decomposing agent is an IgG decomposing agent.

32. The method according to claim 19, wherein the degrading agent is a degrading agent for galactose-deficient immunoglobulin A ("Gd-IgA").

33. The method according to claim 19, wherein the pathogenic protein degradation agent is an anti-β1 ECII autoantibody degradation agent.

34. The method according to claim 19, wherein the pathogenic protein degrading agent is an immunoglobulin E ("IgE") degrading agent.

35. The method according to claim 19, wherein the pathogenic protein degrading agent is an immunoglobulin M ("IgM") degrading agent.

36. A method for reducing the level of pathogenic protein in a subject, comprising administering to the subject a degrader having affinity for hepatocyte asialoglycoglycoprotein (ASGPR) receptors and pathogenic proteins expressed in the liver of the subject, in an amount effective to promote a reduction in the level of pathogenic protein in the subject, such that the PD / PK ratio EC50 / AUC measured 7 to 14 days after administration is at least 1.0 to 1.

8.

37. The method according to claim 36, wherein the administration is performed subcutaneously.

38. The method according to claim 36, wherein the decomposing agent has chemical formula (I), (II), or (III). 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 (in chemical formulas (I), (II), (III) R2 is NHC(=O)CH3; R5 is CH2OH; A pathogenic protein targeting ligand is a ligand that has affinity for pathogenic proteins. [Linker A] is a chemical group that links the ASGPR ligand to linker B, Linker C, or linker D; Linker B is a chemical group that links linker A to a pathogenic protein targeting ligand; [LinkerC] is a chemical group that links LinkerC to a pathogenic protein targeting ligand; and Linker D is a chemical group that links Linker A to a pathogenic protein targeting ligand.

39. The method according to claim 36, wherein the decomposing agent has the following general chemical structure: 【Chemistry 12】 [CPBM] is a pathogenic protein-binding moiety that binds to a pathogenic form of a pathogenic protein identified herein, which is associated with and / or mediates a pathological state and / or condition and is removed by the action of hepatocytes or other cells on circulating proteins (the compound preferably selectively binds to IgG in the plasma of the subject or patient); [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via the asialocrycoprotein receptors or other receptors identified herein, which are present on the surface of hepatocytes and other degraded cells. Each [CON] is either directly connected to the [CPBM] or [CRBM] if present, or is any connector chemical part that connects the [LINKER] to the [CPBM] or [CRBM], and [LINKER] is a chemical moiety having a valency of 1 to 15, which is covalently bonded to one or more [CRBM] and / or [CPBM] groups via [CON] which optionally contains a [MULTICON] group, and the [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself. k' is an integer between 1 and 15; j' is an integer between 1 and 15; h and h' are each independent integers between 0 and 15; iL is an integer between 0 and 15; The present invention relates to compounds of (wherein at least one of h, h', and iL is at least 1), or pharmaceutically acceptable salts, stereoisomers, solvates, or polymorphs thereof.

40. The method according to claim 36, wherein the decomposing agent is an IgG decomposing agent.

41. The method according to claim 36, wherein the degrading agent is a degrading agent for galactose-deficient immunoglobulin A ("Gd-IgA").

42. The method according to claim 36, wherein the pathogenic protein degradation agent is an anti-β1 ECII autoantibody degradation agent.

43. The method according to claim 36, wherein the pathogenic protein degrading agent is an immunoglobulin E ("IgE") degrading agent.

44. The method according to claim 36, wherein the pathogenic protein degrading agent is an immunoglobulin M ("IgM") degrading agent.

45. A method for treating a disease in a subject, comprising administering to the subject in an amount effective to promote a reduction in the level of the pathogenic protein, wherein the administration is carried out in a first step of (a) intravenous administration of the degrading agent and (b) a second step of administration of the degrading agent in a manner other than intravenous administration.

46. The method according to claim 45, wherein the pathogenic protein mediates a disease selected from cancer, heart disease, autoimmune disease, or inflammatory disease.

47. The method according to claim 45, wherein the pathogenic protein is an abnormal immunoglobulin.

48. The method according to claim 47, wherein the immunoglobulin is immunoglobulin A ("IgA"), immunoglobulin D ("IgD"), immunoglobulin E ("IgE"), immunoglobulin G ("IgG"), or immunoglobulin M ("IgM").

49. The method according to claim 48, wherein the abnormal IgA is galactose-deficient immunoglobulin A ("Gd-IgA").

50. The method of claim 45, wherein in the second step, the degrader is administered subcutaneously.

51. The method according to claim 45, wherein in the second step, the decomposing agent is administered transdermally.

52. The method according to claim 45, wherein in the second step, the decomposing agent is administered intramuscularly.

53. The method according to claim 45, wherein the decomposing agent has chemical formula (I), (II), or (III). 【Chemistry 13】 【Chemistry 14】 【Chemistry 15】 (in chemical formulas (I), (II), (III) R2 is NHC(=O)CH3; R5 is CH2OH; A pathogenic protein targeting ligand is a ligand that has affinity for pathogenic proteins. [Linker A] is a chemical group that links the ASGPR ligand to linker B, Linker C, or linker D; Linker B is a chemical group that links linker A to a pathogenic protein targeting ligand; [LinkerC] is a chemical group that links LinkerC to a pathogenic protein targeting ligand; and Linker D is a chemical group that links Linker A to a pathogenic protein targeting ligand.

54. The method according to claim 45, wherein the decomposing agent has the following general chemical structure: 【Chemistry 16】 [CPBM] is a pathogenic protein-binding moiety that binds to a pathogenic form of a pathogenic protein identified herein, which is associated with and / or mediates a pathological state and / or condition and is removed by the action of hepatocytes or other cells on circulating proteins (the compound preferably selectively binds to IgG in the plasma of the subject or patient); [CRBM] is a cell receptor binding moiety, preferably an [ASGPRBM] group, which is a binding moiety that binds to hepatocytes or other cells via the asialocrycoprotein receptors or other receptors identified herein, which are present on the surface of hepatocytes and other degraded cells. Each [CON] is either directly connected to the [CPBM] or [CRBM] if present, or is any connector chemical part that connects the [LINKER] to the [CPBM] or [CRBM], and [LINKER] is a chemical moiety having a valency of 1 to 15, which is covalently bonded to one or more [CRBM] and / or [CPBM] groups via [CON] which optionally contains a [MULTICON] group, and the [LINKER] optionally contains one or more [CON] or [MULTICON] groups itself. k' is an integer between 1 and 15; j' is an integer between 1 and 15; h and h' are each independent integers between 0 and 15; iL is an integer between 0 and 15; The present invention relates to compounds of (wherein at least one of h, h', and iL is at least 1), or pharmaceutically acceptable salts, stereoisomers, solvates, or polymorphs thereof.

55. The method according to claim 45, wherein the decomposing agent is an IgG decomposing agent.

56. The method according to claim 45, wherein the degrading agent is a degrading agent for galactose-deficient immunoglobulin A ("Gd-IgA").

57. The method according to claim 45, wherein the pathogenic protein degradation agent is an anti-β1 ECII autoantibody degradation agent.

58. The method according to claim 45, wherein the pathogenic protein degrading agent is an immunoglobulin E ("IgE") degrading agent.

59. The method according to claim 45, wherein the pathogenic protein degrading agent is an immunoglobulin M ("IgM") degrading agent.

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