1. Circulation, ADC drugs are administered by systemic exposure, and first enter the blood system. Since the relative molecular mass of antibodies is about 150ku, and the relative molecular mass of cytotoxic drugs is about 1ku, the properties of ADC drug circulation are basically the same as “naked”. Antibodies are the same.
2. Binding to the antigen, the antibody recognizes a specific antigenic site, and this process will determine the specificity of targeted delivery.
3. Internalization, after the antibody binds to the receptor on the cell membrane, endocytosis occurs.
4. Drug release, the linker is cleaved in the intracellular lysosome to release the small molecule cytotoxic drug.
5. Play the role of drugs, small molecule cytotoxic drugs play a role to kill tumor cells.
In addition to the above-mentioned common ADC drug designs, some ADC drug designs do not undergo internalization, but are released extracellularly and play a role in the local microenvironment.