As an industry leader in antibody engineering field, experts from Bio.services have developed CreativeAb™ antibodies in order to increase the efficacy of current therapeutic antibodies. Bispecific antibodies (BsAbs) are bioengineered antibodies that contain two different binding sites within a single molecule, which can specifically bind two different types of antigen. The most widely used application of bispecific antibody is in cancer immunotherapy, which creates a therapeutic treatment approach for diseases with specific medical needs.

Compared with traditional antibodies, bispecific antibodies have many advantages. The two arms can bring an antigen-expressing cell in close proximity to a killing cell and thus destroy the tumor cell; the two binding sites can significantly increase affinity or internalization rates of particular antigens on a cell’s surface by binding to two different epitopes on an antigen; they usually have a higher cytotoxic potential to bind to antigens with low expression level. Binding tumor cells using a bispecific antibody-drug conjugate (ADC) also holds great promise for the future development of therapeutics for a variety of diseases.

With the development of antibody engineering, many types of bispecific antibodies have been designed to overcome short half-life, immunogenicity and side-effects caused by cytokine liberation. They include trifunctional antibodies, chemically linked Fabs, various types of bivalent and trivalent single chain variable fragments (scFvs), and fusion proteins mimicking the variable domains of two antibodies. The furthest developed of these newer formats are the bispecific T cell engagers (BiTEs) and mAb2’s, antibodies engineered to contain an Fcab antigen-binding fragment instead of the Fc constant region.