FC SILENCED ANTIBODY DRUG CONJUGATES (ADCS) AND USES THEREOF
Disclosed are antibodies and antibody drug conjugates having an Fc region with substitutions resulting in essentially a silent Fc region. The antibodies and antibody drug conjugates described herein are useful for the depletion of cells and for the treatment of various hematopoietic diseases, metabolic disorders, cancers, e.g., acute myeloid leukemia (AML) and autoimmune diseases, among others. The compositions and methods described herein can be used to treat a disorder directly, for instance, by depleting, e.g., a population of CD45+ or CD117+ cancer cells or CD45+ 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.
1 . An antibody, or antigen-binding portion thereof, comprising an Fc region, wherein the Fc region comprises amino acid substitutions consisting essentially of amino acid substitutions L234A, L235A, and D265C (EU index.
2 . An antibody, or antigen-binding portion thereof, comprising an Fc region, wherein the Fc region comprises amino acid substitutions consisting essentially of amino acid substitutions L234A, L235A, S239C and D265A (EU index).
3 . An antibody, or antigen-binding portion thereof, comprising an Fc region, wherein the Fc region comprises amino acid substitutions consisting essentially of amino acid substitutions H435A, L234A, L235A, and D265C (EU index).
4 . The antibody, or antigen-binding portion of claim 1 , wherein the antibody, or the antigen-binding region, is conjugated to a cytotoxin.
5 . The antibody, or antigen-binding portion of claim 2 , wherein the antibody, or the antigen-binding region, is conjugated to a cytotoxin.
6 . The antibody, or antigen-binding portion of claim 3 , wherein the antibody, or the antigen-binding region, is conjugated to a cytotoxin.