What are the targeted drug therapies for colorectal cancer?
Apr 20, 2022
Source: Cainiu Health
Dr. Peng Xiaodong
Introduction
What targeted drug therapies are available for colorectal cancer? Currently, two primary targeted drugs are used clinically in China for treating colorectal cancer. One is cetuximab (Erbitux®), which blocks signal transduction pathways in tumor cells, thereby exerting antitumor effects. The other is bevacizumab (Avastin®), which targets vascular endothelial growth factor (VEGF) to inhibit tumor angiogenesis. When combined with chemotherapy, these two targeted agents can improve patient survival rates.
Colorectal cancer is a common malignant gastrointestinal tumor arising in the colon, most frequently occurring at the junction of the rectum and sigmoid colon. Tumor cells can obstruct the colon and invade the colonic wall, leading to symptoms such as intestinal obstruction, hematochezia (rectal bleeding), pain, and abdominal pain. Additionally, colorectal cancer may metastasize to the liver, peritoneal cavity, bones, brain, and other sites. As a malignant tumor, it poses a serious threat to life. So, what targeted drug therapies are available for colorectal cancer? Let’s explore them below.
Targeted Drug Therapies for Colorectal Cancer
Currently, two primary targeted drugs are used clinically in China for treating colorectal cancer. The first is Cetuximab (Erbitux®), which blocks signal transduction pathways within tumor cells, thereby exerting antitumor effects. The second is Bevacizumab (Avastin®), which targets vascular endothelial growth factor (VEGF) on tumor blood vessel endothelium. When combined with chemotherapy agents, Bevacizumab increases tumor vascular permeability, facilitating delivery of chemotherapeutic drugs to kill tumor cells; it also promotes normalization—shrinking and occlusion—of abnormal tumor vasculature.
Cetuximab and Bevacizumab differ in their mechanisms of action: Cetuximab acts on the epidermal growth factor receptor (EGFR) expressed on tumor cells (not directly on blood vessels, though its downstream effects impact angiogenesis), while Bevacizumab directly targets VEGF to inhibit tumor angiogenesis. When either agent is combined with chemotherapy, clinical efficacy improves significantly. Chemotherapy alone achieves response rates of 40–50% in colorectal cancer; adding targeted therapy raises this rate by over 10%. In patients with colorectal cancer confined to liver metastases, combination chemotherapy plus targeted therapy can elevate response rates to approximately 70%, substantially improving patient survival outcomes.
The above outlines the currently available targeted drug therapies for colorectal cancer. These targeted agents are typically indicated for advanced-stage disease and are often administered in conjunction with chemotherapy. We hope this information proves helpful.
