TARGETED THERAPIES
Types of targeted therapy
Kinase inhibitors
Kinase inhibitors are drugs that target specific proteins known as kinases, which regulate cell functions such as signaling, growth, and division. Examples of kinases include ALK, EGFR, MET, NTRK, RET, ROS1. The BRAF gene encodes a different type of kinase, serine/threonine. If these genes have driver mutations, they can prompt cancer cells to proliferate. Approved kinase inhibitors as targeted therapy for lung cancer driver mutations block cell functions to inhibit cancer growth and division. Most of these inhibitors are tyrosine kinase inhibitors (TKIs) and are taken orally, except for a combination treatment for BRAF V600E mutation.
Bispecific antibodies
Bispecific antibodies are molecules capable of targeting two antigens simultaneously, which are substances provoking immune responses. Unlike natural antibodies that bind to only one antigen, these artificial antibodies can block signaling pathways crucial for cancer cell growth. For instance, a bispecific antibody has been created to target a particular variant of the EGFR gene. This drug is administered intravenously.
RAS GTPase family inhibitors
RAS GTPase family inhibitors are drugs designed to counteract the effects of mutations in the KRAS gene, which result in the constant activation of the KRAS protein, leading to uncontrolled cell growth and tumor formation in lung cancer. These inhibitors specifically target the most prevalent mutation of the KRAS gene (G12C) found in non-small cell lung cancer (NSCLC).
Topoisomerase inhibitor antibody-drug conjugates (ADCs)
Topoisomerase inhibitor antibody-drug conjugates (ADCs) combine a monoclonal antibody with a drug to selectively target cancer cells. The antibody binds to specific proteins on cancer cells, allowing the linked drug to enter and kill them without harming healthy cells. Topoisomerases are enzymes vital for cell division, and blocking them can lead to cancer cell death. Administering a topoisomerase inhibitor with an ADC ensures more precise drug delivery to tumor cells with minimal harm to healthy cells, reducing side effects compared to nonspecific targeting.
Targeted therapy can serve as a standalone treatment or be combined with other therapies based on various factors such as the timing of discovering the driver mutation, patient response, and individual health considerations. Additional treatments may include other targeted therapies, chemotherapy, chemotherapy-immunotherapy, angiogenesis inhibitors, or radiation therapy. When multiple approved therapies for a specific mutation are available, doctors tailor the treatment based on individual patient factors.
