Zolbetuximab - Is Vyloy an ADC drug?

Zolbetuximab, trade name Vyloy, is a targeted antibody drug used to treat Claudin 18.2-positive gastric cancer and gastroesophageal junction (GEJ) adenocarcinoma. Its mechanism of action is different from traditional chemotherapy drugs and other targeted therapy drugs, so it shows unique advantages in the treatment of cancer. However, many patients and medical professionals may have questions about whether to classify it as an "antibody drug conjugate" (ADC). Briefly, zotuximab is not an ADC drug, but a simple targeted antibody treatment drug.

First of all, it is necessary to clarify the definition of ADC drugs. ADC drugs are formed by linking an antibody to a cytotoxic drug. The antibody part can accurately target and attach to the surface of tumor cells, while the cytotoxic drugs are guided by the antibodies into the interior of the tumor cells to kill them. The most famous ADC drugs include Trastuzumab emtansine (T-DM1), etc. The advantage of ADC is to precisely target drugs to cancer cells, thereby reducing damage to normal cells and reducing side effects.

UnlikeADC drugs, zotuximab is not combined with any cytotoxic drugs. It is a pure antibody drug that works specifically by targeting the Claudin 18.2 protein. Claudin 18.2 is a protein expressed on the surface of some cancer cells, especially in gastric cancer and gastroesophageal junction adenocarcinoma. Zotuximab eliminates cancer cells by binding to the Claudin 18.2 protein on the surface of these cells, inducing antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). This makes it a targeted therapy rather than an ADC.

Reference: https://en.wikipedia.org/wiki/Zolbetuximab