Trispecific inhibitors for cancer treatment

Abstract

A trispecific inhibitor for treating cancer includes a first targeting domain having a binding specificity conferred by a VEGF binding antagonist; a second targeting domain having a binding specificity conferred by an immune checkpoint regulator binding antagonist; and a third targeting domain having a binding specificity conferred by a Tie2 tyrosine kinase receptor binding antagonist. The targeting domains may contain one or more antibody variable regions, peptide inhibitors, dominant negative proteins, small molecule drugs or combinations thereof.

What is claimed is: 
     
         1 . A trispecific antibody, comprising:
 a first targeting domain having a first binding specificity to an immune checkpoint regulator;   a second targeting domain having a second binding specificity to vascular endothelial growth factor (VEGF) or a vascular endothelial growth factor receptor (VEGFR); and   a third targeting domain having a third binding specificity to a ligand of Tie2 tyrosine kinase receptor or to a Tie2 tyrosine kinase receptor,   wherein the first targeting domain and the second targeting domain each comprises one or more antibody variable regions.   
     
     
         2 . The trispecific antibody of  claim 1 , wherein at least two targeting domains comprise at least one antibody fragment selected from the group consisting of single domain antibody (sdAb), a fragment variable (Fv) heterodimer, a single chain Fv (scFv), Fab fragment, and combination thereof. 
     
     
         3 . The trispecific antibody of  claim 1 , wherein the immune checkpoint regulator is an checkpoint regulator antagonist selected from the group consisting of PD-1, PD-1 PD-L1, PD-L2, CTLA-4, 17-1, B7-2, TIM-3, Galectin-9, LAG-3, liver sinusoidal endothelial cell lectin (LSECtin), Galectin-3, T cell Ig and ITIM domain (TIGIT), CD155 ligand, CD122, CD122R ligand, CD70, 87H3, B and T lymphocyte attenuator (BTLA), and VISTA, and wherein the immune checkpoint regulator is an checkpoint regulator agonist selected from the group consisting of CD27, CD40, OX40, glucocorticoid-induced TNFR family-related protein (GITR), CD137, CD28 and ICOS. 
     
     
         4 . The trispecific antibody of  claim 1 , wherein the immune checkpoint regulator is PD-1 and wherein the second binding specificity is directed against VEGF. 
     
     
         5 . The trispecific antibody of  claim 4 , wherein the third targeting domain comprises an inhibitory peptide to angiopoietin 1 (Ang 1) and/or angiopoietin 2 (Ang 2). 
     
     
         6 . The trispecific antibody of  claim 1 , wherein the third targeting domain comprises SEQ ID NO:1 or SEQ ID NO:2. 
     
     
         7 . The trispecific antibody of  claim 1 , wherein the first targeting domain comprises one or more antibody fragments from nivolumab and wherein the second targeting domain comprises one or more antibody fragments from bevacizumab. 
     
     
         8 . The trispecific antibody of  claim 7 , wherein the third targeting domain comprises SEQ ID NO:1 or SEQ ID NO:2. 
     
     
         9 . The trispecific antibody of  claim 8 , wherein the first target domain comprises SEQ ID NO:14 and SEQ ID NO:16. 
     
     
         10 . The trispecific antibody of  claim 8 , wherein the second target domain comprises SEQ ID NO:6 and SEQ ID NO:7. 
     
     
         11 . The trispecific antibody of  claim 1 , wherein the first target domain comprises SEQ ID NO:14 and SEQ ID NO:16, wherein the second target domain comprises SEQ ID NO:6 and SEQ ID NO:7, and wherein the third targeting domain comprises SEQ ID NO:1. 
     
     
         12 . The trispecific antibody of  claim 11 , wherein the trispecific antibody comprises SEQ ID NO:24 and SEQ ID NO:25. 
     
     
         13 . The trispecific antibody of  claim 11 , wherein the trispecific antibody comprises SEQ ID NO:26 and SEQ ID NO:27. 
     
     
         14 . The trispecific antibody of  claim 11 , wherein the trispecific antibody comprises SEQ ID NO:38 and SEQ ID NO:39. 
     
     
         15 . The trispecific antibody of  claim 1 , comprising two immunoglobulin heavy chains and two immunoglobulin light chains, wherein the third targeting domain is covalently linked to the C-terminal end of one or both immunoglobulin light chains. 
     
     
         16 . The trispecific antibody of  claim 15 , wherein either one of the first or second targeting domain comprises a single chain Iv (scFv) covalently linked to the C-terminal end of one or both immunoglobulin heavy chains. 
     
     
         17 . The trispecific antibody of  claim 16 , wherein the first targeting domain comprises a pair of scFvs with a binding specificity to PD-1. 
     
     
         18 . The trispecific antibody of  claim 1 , wherein each of the targeting domains is linked to a protein scaffold comprising a heterodimer of one or more mutant immunoglobulin constant regions, where the mutant immunoglobulin constant region chains are configured to preferentially form a heterodimer when co-expressed in cultured cells. 
     
     
         19 . A trispecific antibody, comprising:
 a first targeting domain having a binding specificity to vascular endothelial growth factor A (VEGF-A);   a second targeting domain having a binding specificity to PD-1;   a third targeting domain having a binding specificity to angiopoietin 1 and/or angiopoietin 2; and   a protein scaffold comprising two polypeptides, wherein each polypeptide comprises a constant domain of an immunoglobin.   
     
     
         20 . A method for treating a cell proliferative disorder, comprising:
 administering to a subject in need thereof the trispecific antibody of  claim 1  in an amount effective to treat the proliferative disorder.