Ponatinib is not a chemotherapy drug but one of many “targeted therapies.” Targeted therapy results from about 100 years of research dedicated to understanding the differences between cancer cells and normal cells. To date, cancer treatment has focused primarily on killing rapidly dividing cells because one feature of cancer cells is that they divide rapidly. Unfortunately, some of our normal cells divide rapidly, too, causing multiple side effects.

Targeted therapy is about identifying other features of cancer cells. Scientists look for specific differences between cancer cells and normal cells. This information is used to create a targeted therapy to attack the cancer cells without damaging the normal cells, thus leading to fewer side effects. Each type of targeted therapy works a little bit differently. Still, all interfere with the ability of the cancer cell to grow, divide, repair, and communicate with other cells.

There are different types of targeted therapies, defined in three broad categories. Some targeted therapies focus on the internal components and function of the cancer cell. The targeted therapies use small molecules that can get into the cell and disrupt the function of the cells, causing them to die. Several types of targeted therapy focus on the inner parts of the cells. Other targeted therapies target receptors that are on the outside of the cell. Therapies that target receptors are also known as monoclonal antibodies. Antiangiogenesis inhibitors target the blood vessels that supply oxygen to the cells, ultimately causing the cells to starve.

Ponatinib is designed to block tumor cell growth in several ways. Ponatinib targets several proteins (called tyrosine kinases) on the surface of cancer cells and targets within the cell. Several of these targets are thought to be involved in angiogenesis (making of blood vessels). By blocking these targets, it is hoped cancer will shrink.

Research continues to identify which cancers may be best treated with targeted therapies and to identify additional targets for more types of cancer.