Targeted therapy is sometimes called precision medicine or personalized medicine. This is because they are made to exactly target specific changes or substances in cancer cells, and these targets can be different even when people have the same type of cancer. Certain types of tumors are tested for different targets after a Biopsy or surgery, and this can help find the most effective treatment. Finding a specific target makes matching patients with treatment more precise or personalized.
Some targeted drugs are more “targeted” than others are. Targeted therapies are classified as either small or large molecule drugs.
- Small molecule drugs are tiny enough to enter a cancer cell once they find it. They work by targeting a specific substance inside the cell and blocking it.
- Large molecule drugs usually cannot fit into a cell. They work by attacking then weakening or destroying proteins or enzymes on the surface of the cell. They are often described as a “lock and key” because the molecule is like a key that opens the enzyme or protein on the surface of the cell like a lock. The key fits into the lock, allowing the drug to work.