Antibody drug conjugates (ADC) are the conjugation of small molecule cytotoxic drugs (payloads) and monoclonal antibody (McAb) drugs through linkers, which are used to improve the targeting of tumor drugs, reduce toxic and side effects, and increase the efficacy toxicity window. Cytotoxins (such as MMAE) are generally not able to be used alone because of their strong toxicity. By recognizing tumor surface antigen and receptor-mediated endocytosis, ADC can release highly active cytotoxins in tumor cells or tissues, thus reducing the peripheral toxicity of cytotoxins and increasing the anti-tumor activity, with higher tolerance or lower side effects. Hongcheng has a screening platform for antibody coupled drugs based on indirect labeling, a new generation of site-specific coupling methods and cytotoxins, and will combine with the company’s powerful antibody discovery platform to develop new antibody coupled drugs.