Abzyme’s platform introduces an additional antigen-binding site by fusing a single domain antibody onto the C-terminus of an IgG Fc of a different specificity to create a so-called Abz2 molecule. This simple rapid fusion transforms an existing antibody into a bispecific antibody without compromising its original target binding affinity. This example shows why the single domain antibody is the key building block of Abzyme Modular Antibody Technology. Abzyme will utilize the VHH C-terminal library to isolate single domain antibody with desired attributes which retain after fusion to the C-terminus of the IgG Fc. Single domain antibody molecules are incredibly versatile, well-expressible and can serve as a building block for creating different classes of biologics depending on the therapeutic need including:
• Ideal building block to generate bispecific as well as multi-specific antibody molecules
• Abz2 bispecific antibodies
• Each particular single domain that binds to a target of interest is selected and optimized from a human or camelid single domain antibody library with enhanced diversity generated by inducible hypermutation
An Abz2 bispecifics retains the benefits of a traditional antibody:
• Excellent binding characteristics (affinity, specificity)
• Favorable pharmacokinetics
• Ability to mobilize immune effector functions
• Protein stability
• Low immunogenic potential