Compared with traditional humanized antibodies or antibody fragments, ADCs can release highly active cytotoxins in tumor tissues and have higher efficacy. Compared with fusion proteins, ADCs have higher tolerability and lower side effects. ADC not only has strong killing power but also combines the high targeting ability of recombinant monoclonal antibodies without affecting normal cells. Therefore, it has received widespread attention in the field of rare disease research. There are already cases of ADCs for rare diseases: