summary
Targeted therapy is a significant progress in cancer therapy. Compared with traditional cytotoxic drugs, targeted therapy has higher efficacy and better tolerance. Antibody coupled drugs (ADC) in targeted therapy is one of the hot research directions in the field of anti-tumor in recent years. At present, 15 ADC drugs have been approved to market in the world, and more than 70 ADC drugs in China are at different research and development stages. In addition, more types of conjugated drugs have been continuously developed, including peptide conjugated drugs (PDC), virus like drug conjugates (VDC), antibody fragment conjugated drugs (FDC), antibody immunostimulatory conjugates (ISAC), antibody biopolymer conjugates (ABC), etc.
In addition to ADC, most of other new coupling drugs are in the early stage, and PDC is relatively developed. It may become the next hot spot like ADC in the future.
Introduction to PDC drugs
There are three components of peptide coupled drug PDC: targeted peptide, cytotoxic drug (small molecule drug) and linker. As a targeted drug delivery carrier, targeted peptides are covalently coupled with toxic drug molecules to enhance drug targeting.
The structure of PDC is similar to that of ADC, but the difference is that the targeting unit of PDC is changed from monoclonal antibody to polypeptide. The mechanism of PDC is also similar to that of ADC. It covalently connects targeted peptides and cytotoxins through the decomposable link chain in cells, accurately targets specific receptors of tumor cells, and controllable releases cytotoxins to kill tumor cells.
PDC integrates the advantages of peptides and has the following advantages compared with ADC drugs: ① smaller molecular weight and stronger tumor penetration; ② Compared with the complex process of antibody production, it is easier to synthesize and purify, and the production cost is lower; ③ The immunogenicity is lower, and it is not easy to cause immune stress response; ④ It can be quickly eliminated by the kidney and has lower toxicity to bone marrow and liver.
Due to its many advantages, PDC is expected to become a new generation of targeted anticancer drugs after small molecule drugs, monoclonal antibodies and ADC drugs.
