The invention provides compositions and methods useful for the depletion of cells, such as CD45+, CD135+, CD34+, CD90+, and/or CD110+ cells, and for the treatment of various hematopoietic diseases, metabolic disorders, cancers, and autoimmune diseases, among others. Described herein are antibodies, antigen-binding fragments, ligands, and conjugates thereof that can be applied to effect the treatment of these conditions, for instance, by depleting a population of CD45+, CD135+, CD34+, CD90+, or CD110+ cells in a patient, such as a human. The compositions and methods described herein can be used to treat a disorder directly, for instance, by depleting a population of CD45+, CD135+, CD34+, CD90+, or CD110+ cancer cells or autoimmune cells. The compositions and methods described herein can also be used to prepare a patient for hematopoietic stem cell transplant therapy and to improve the engraftment of hematopoietic stem cell transplants by selectively depleting endogenous hematopoietic stem cells prior to the transplant procedure.

The present disclosure provides antibody-drug conjugate structures, which include a cleavable linker that links the antibody to the drug and has a first enzymatically cleavable moiety and a second enzymatically cleavable moiety which includes a glycoside selected from a galactoside, a glucoside, a mannoside, a fucoside, O-GlcNAc, and O-GalNAc. The disclosure also encompasses compounds and methods for production of such conjugates, as well as methods of using the conjugates.

The invention relates to a conjugate comprising (a) an amatoxin comprising (i) an amino acid 4 with a 6-deoxy position; and (ii) an amino acid 8 with an S-deoxy position; (b) a target-binding moiety; and (c) optionally a linker linking said amatoxin and said target-binding moiety. The invention furthermore relates to a pharmaceutical composition comprising such conjugate.

The present application relates to conjugates comprising an amatoxin, a target-binding moiety wherein the target is CD37, i.e., a CD37-binding moiety, and optionally a linker linking said amatoxin and said CD37-binding moiety. The invention further relates to the synthesis of said conjugates. In addition, the invention relates to a pharmaceutical composition comprising such conjugate for use in the treatment of immune cell, particularly B-cell and/or lymphoma associated diseases and/or malignancies (FIG. 1).

In some aspects, the invention relates to an antibody-drug conjugate, comprising an anti-CD19 antibody; a linker; and an active agent. The antibody-drug conjugate may comprise a self-immolative group. The linker may comprise an O-substituted oxime, e.g., wherein the oxygen atom of the oxime is substituted with a group that covalently links the oxime to the active agent; and the carbon atom of the oxime is substituted with a group that covalently links the oxime to the antibody.

The present application relates to conjugates comprising an amatoxin, a target-binding moiety wherein the target is CD37, i.e., a CD37-binding moiety, and optionally a linker linking said amatoxin and said CD37-binding moiety. The invention further relates to the synthesis of said conjugates. In addition, the invention relates to a pharmaceutical composition comprising such conjugate for use in the treatment of immune cell-, particularly B-cell and/or lymphoma associated diseases and/or malignancies.

Disclosed is a non-natural amatoxin-type antibody conjugate, said conjugate similar to the natural amatoxin is linked to a biopharmaceutically acceptable salt with a target biomolecule so as to obtain stability in blood plasma, and efficiently kill tumor cells in cells.

The invention provides anti-CD5 antibodies, antigen-binding fragments thereof, and antibody drug conjugates thereof, for use in treating, for example, a stem cell disorder, cancer, or autoimmune disease, among other hematological and proliferative diseases. Compositions and methods for depleting populations of CD5+ cells, such as CD5+ cancer cells and CD5+ immune cells are described, and can be used to treat cancers and autoimmune diseases directly as stand-alone therapies by eradicating cancerous cells and autoreactive immune cells that express CD5 and/or to prepare a patient for hematopoietic stem cell transplantation, for instance, by depleting populations of CD5+ immune cells that cross-react with, and mount an immune response against, non-self hematopoietic stem cells.

The invention provides anti-CD5 antibodies, antigen-binding fragments thereof, and antibody drug conjugates thereof, for use in treating, for example, a stem cell disorder, cancer, or autoimmune disease, among other hematological and proliferative diseases. Compositions and methods for depleting populations of CD5+ cells, such as CD5+ cancer cells and CD5+ immune cells are described, and can be used to treat cancers and autoimmune diseases directly as stand-alone therapies by eradicating cancerous cells and autoreactive immune cells that express CD5 and/or to prepare a patient for hematopoietic stem cell transplantation, for instance, by depleting populations of CD5+ immune cells that cross-react with, and mount an immune response against, non-self hematopoietic stem cells.

The present disclosure relates to antibody-drug conjugates (ADCs) wherein one or more active agents are conjugated to an anti-B7-H3 antibody through a linker. The linker may comprise a unit that covalently links active agents to the antibody. The disclosure further relates to monoclonal antibodies and antigen binding fragments, variants, multimeric versions, or bispecifics thereof that specifically bind B7-H3, as well as methods of making and using these anti-B7-H3 antibodies and antigen-binding fragments thereof in a variety of therapeutic, diagnostic and prophylactic indications.