Remarkable advancements have taken place in recombinant antibody sciences, and made possible significant clinical success of therapeutic antibody drugs. However, major challenges remain, such as the anti-drug antibody (ADA) issue associated with the immunogenicity of non-human antibodies. This response occurs when human immune systems react to the foreign protein, leading to moderate to serious safety and efficacy concerns. To tackle this issue, chimeric antibodies were created, where the antibody’s variable domains were recombined with human constant domains, thus preserving antibody specificity.1 However, the problem of immunogenicity-triggered liabilities needs to be further targeted.