Tetravalent FZD and WNT Co-Receptor Binding Antibody Molecules and Uses Thereof

A nucleic acid molecule encoding a polypeptide of a tetravalent binding antibody molecule comprising an N-terminal LRP5-binding diabody and a C-terminal domain comprising two FZD4-binding scFv, the tetravalent binding antibody molecule comprising a dimer of a first and second monomer, wherein each monomer comprises a single-chain polypeptide comprising, from N-terminus to C-terminus:

• (a) a first peptide, said first peptide comprising a first heavy chain variable domain (VH) and a first light chain variable (VL) domain that bind LRP5,
• (b) an Fc region, or fragment thereof comprising a constant heavy chain domain 3 (CH3), and
• (c) a second peptide, said second peptide comprising a second VL and a second VH that bind a FZD4, and
• wherein the first and second monomers dimerize via the Fc regions or fragments thereof, the first VH and VL of each monomer pairs with the first VH and VL of the other monomer forming a diabody that binds LRP5 and the second VL and VH of each monomer pair to form a scFvs that bind FZD4, and
• wherein the LRP5-binding diabody forms the N-terminal LRP5-binding domain of the tetravalent binding antibody molecule and the two FZD4-binding scFvs form the C-terminal FZD-binding domain of the tetravalent binding antibody molecule.

A nucleic acid molecule encoding a polypeptide of a tetravalent binding antibody molecule comprising an N-terminal LRP5-binding diabody and a C-terminal domain comprising two FZD4-binding Fab, the tetravalent binding antibody molecule comprising

• (1) a first and second heavy chain monomer, wherein each heavy chain monomer comprises a single-chain polypeptide comprising, from N-terminus to C-terminus:
• (a) a peptide comprising a heavy chain variable (VH) domain that binds a LRP5 co-receptor and a light chain variable (VL) domain that binds a LRP5 co-receptor, linked to,
• (b) an Fc region, or fragment thereof comprising a constant heavy chain domain 3 (CH3), linked to
• (c) a VH domain that binds FZD4, linked to
• (d) a CH1 domain, and
• (2) a first and second light chain monomer each light chain monomer comprising from N-terminus to C-terminus a VL domain that binds FZD4, and a constant light chain domain 1 (CL1)
• wherein a linker between the VH and VL that binds the LRP5 is of a length that promotes the pairing of the VH and VL of the first heavy chain monomer with the VL and VH of the second heavy chain monomer thereby forming a LRP5 co-receptor binding diabody and the FZD-binding Fabs are formed by the pairing of each heavy chain monomer with a light chain monomer such that the VH that binds FZD4 and CH1 of each of the heavy chain monomer, pairs with the VL that binds FZD4 and CL1 of the light chain monomers, and
• wherein the LRP5-binding diabody forms the N-terminal LRP5-binding domain of the tetravalent binding antibody molecule and the two FZD4-binding Fabs form the C-terminal FZD-binding domain of the tetravalent binding antibody molecule.

A nucleic acid molecule encoding a polypeptide of a tetravalent binding antibody molecule comprising an Fc domain or fragment thereof comprising a constant heavy chain domain 3 (CH3), an N-terminal FZD4 binding domain comprising two FZD4-binding Fabs and a C-terminal LRP5 binding domain comprising a LRP5 binding diabody, the tetravalent binding antibody molecule comprising

• (a) a first and second heavy chain monomer, wherein each heavy chain monomer comprises a single-chain polypeptide comprising from N-terminus to C-terminus:
• (i) a heavy chain variable domain (VH) that binds FZD4, linked to
• (ii) a heavy chain constant region domain 1 (CH1 domain), linked to
• (iii) the CH2 domain of the Fc region linked to
• (iv) a peptide comprising a VH that binds a LRP5 co-receptor, linked to a light chain variable domain (VL) that binds a LRP5 co-receptor, and
• (b) a first and second light chain monomer, each light chain monomer comprising from N terminus to C terminus a VL that binds the FZD4, linked to a constant light chain domain 1 (CL1 domain),
• wherein the first and second heavy chain monomers dimerize via their Fc regions, or fragments thereof,
• wherein a linker between the VH and VL that binds the LRP5 is of a length that promotes the pairing of the VH and VL of the first heavy chain monomer with the VL and VH of the second heavy chain monomer thereby forming a LRP5 co-receptor binding diabody and the FZD-binding Fabs are formed by the pairing of each heavy chain monomer with a light chain monomer such that the VH that binds FZD4 and CH1 of each of the heavy chain monomer, pairs with the VL that binds FZD4 and CL1 of the light chain monomers, and
• wherein the Fabs form the FZD4-binding domain on the N-terminus of the Fc domain and the diabody forms the LRP5 co-receptor-binding domain on the C-terminus of the Fc domain.