Recombinant Anti-CD89 x Anti-EGFR Bispecific Antibody (Tandem scFv-Fc) is designed to be expressed as a homodimer, which has 2+2 antigen-binding valency. This format consists of one Fc region and two tandem scFv fragments, in which the anti-CD89/EGFR tandem scFv is fused to the Fc domain. The engineered fragment format is used to extend the half-life. This BsAb can retarget macrophages to tumor cells. It is designed for the research of Head and neck cancer; Colorectal cancer (CRC); Glioblastoma multiforme (GBM); Squamous cancer; Non-small cell lung cancer (NSCLC); Solid tumors therapy.