What is difference between chemotherapy and targeted therapy?
March 30, 2021
We have been asked often what is the difference between chemotherapy and targeted therapy. We were planning to write something to explain, but came across this excellent article emedicinehealth.com/chemothera.../article_em.htm
Targeted therapy is the foundation of personalized or precision medicine. In order to find the best targeted therapy for each patient, the molecular profiling of tumor is necessary. As with any other drugs, targeted therapy drugs also have side effects, sometimes it could be severe. However, because targeted therapy drugs affect mostly cancer cells, not healthy cells, they are generally less toxic than chemotherapy drugs, so that cancer patients can have a better quality of life during treatment.
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What are the types of targeted therapy drugs?
1. Small-molecule inhibitor drugs
As the name suggests, these drugs are small enough to get in cells and block specific proteins (targets) which make cells become cancerous. The generic name of these drugs usually ends with -nib or -mib. For example, ibrutinib which blocks the protein called bruton’s tyrosine kinase (BTK) in lymphoma cancer cells. The other example is Bortezomib, one of the first line drugs of multiple myeloma. Bortezomib blocks proteasomes, protein complexes which regulate protein amounts in cells as well as cell division and survival.
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2. Monoclonal Antibody
Monoclonal antibody drugs target proteins on the surface of the cancer cells and thus stop cancer cells from growing. The generic name of these drugs ends with -mab. The first monoclonal antibody approved by the FDA was rituximab which targets the protein called CD20 in B cell lymphoma cells. Another good example of monoclonal antibody drug is trastuzumab (Herceptin) which targets and inhibits the function of the protein called HER2 in breast and gastric cancer cells.
Immune checkpoint inhibitors, pembrolizumab and nivolumab are also monoclonal antibody drugs. These drugs target and inhibit the function of the protein called programmed death (PD)-1, a checkpoint protein in cytotoxic or killer T cells.
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If you have any further question regarding chemotherapy and targeted therapy, we are here to answer your questions!
https://www.emedicinehealth.com/chemothera.../article_em.htm