Biological Therapies for Metastatic Colorectal Cancer: Literature Review

Colorectal cancer is among the most prevalent and lethal malignancies worldwide. Its initially asymptomatic nature contributes to a high incidence of metastatic cases. Although predominantly diagnosed in older adults, the incidence among younger populations is rising at an alarming rate. Historically, treatment has relied on antineoplastic agents such as 5-fluorouracil, irinotecan, and oxaliplatin. While these agents remain in use, their effectiveness is limited, particularly in metastatic disease, with modest improvements in overall survival and progressionfree survival. Moreover, their low target specificity results in significant systemic toxicity. This underscores the urgent need formore selective and less toxic therapeutic strategies, such as monoclonal antibodies. Monoclonal antibodies targeting Vascular Endothelial Growth Factor (VEGF), Epidermal Growth Factor Receptor (EGFR), and immune checkpoints have become integral to the management of metastatic colorectal cancer. Notable examples include bevacizumab (anti-VEGF), cetuximab and panitumumab (anti-EGFR), and the immune checkpoint inhibitors pembrolizumab, nivolumab, and ipilimumab. Their clinical success especially when guided by molecular tumour profiling highlights their contribution to improved patient outcomes. In addition, other targeted therapies distinct from monoclonal antibodies are currently under investigation.