TRISPECIFIC INHIBITORS FOR CANCER TREATMENT
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.
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.