Erlotinib cancer drug, Computer model of a molecule of the cancer drug erlotinib. Atoms are represented as spheres and are colour-coded: carbon (yellow), hydrogen (white), oxygen (pink) and nitrogen (green). This drug, which is marketed as Tarceva, is used to treat non-small cell lung cancer and pancreatic cancer. It belongs to a class of drugs known as tyrosine kinase inhibitors. These drugs bind to tyrosine kinase growth factor receptors on the cancer cell's surface, inactivating them and so stopping cell growth and proliferation.