Recombinant Anti-EGFR x Anti-IGF1R Bispecific Antibody (scFv4-Ig) is an appended IgG format, which includes four scFv moieties at the N-termini of the constant regions. It is a bivalent homodimer, in which one anti-EGFR scFv is fused to the CH1 domain of a heavy chain and another anti-IGF1R scFv to the CL domain of a light chain, or vice versa. The resulting leads to 2+2 antigen-binding valency. This BsAb can bind and inactivate two receptors simultaneously. It is designed for the research of Colorectal cancer; Cervical cancer; Breast cancer; Pancreatic cancer therapy.