Abstract: Disclosed is a fusion protein of a mutated recombinant single-chain human coagulation factor VIII (FVIII), a preparation method therefor, and a use thereof. The fusion protein sequentially comprises, from an N-terminus to a C-terminus, a mutated single-chain human FVIII having a partially deleted B-domain, a flexible peptide linker, at least one rigid unit of a carboxyl-terminal peptide of a human chorionic gonadotropin beta subunit, and a half-life prolonging moiety (preferably an IgG Fc variant). The fusion protein has a similar biological activity to a recombinant FVIII, a prolonged active half life in vivo, and better stability in vitro and in vivo, and thus improves the pharmacokinetics and efficacy of the fusion protein.

Abstract: Provided is a tetravalent homodimeric bispecific antibody molecule simultaneously targeting an immune effector cell antigen CD3 and a tumor-associated antigen, wherein the bispecific antibody molecule contains, in order from N-terminus to C-terminus, a first single chain Fv, a second single chain Fv and a Fc fragment; wherein the first single chain Fv can specifically bind to the tumor-associated antigen, the second single chain Fv can specifically bind to CD3, and the first and the second single chain Fvs are connected by a linker peptide, while the second single chain Fv and the Fc fragment are directly connected or connected by a linker peptide; and the Fc fragment does not have effector functions such as CDC, ADCC and ADCP.