Panitumumab is never used by itself as a mono therapy. It is in the same family of drugs as already approved Erbitux, they are both monoclonal antibodies that interfere with a cells ability to reproduce. This is a good thing since cancer cells replicate much faster than normal cells, and slowing them down while OTHER treatments, like conventional chemo and radiation, can work more effectively. They both were used in colon cancer as their proving ground. This drug was introduced in 06 in colon, but the manufacturer is trying to expand sales into head and neck like BMS did with Erbitux. Hence the clinical trials.