Phase III trials involve a larger number of people and are the final phase aimed at determining whether a treatment or drug actually works. Such cancers, heavily associated with the use of alcohol and tobacco, are treated at first with surgery, radiation therapy or both. But tumors come back in about a third of patients. When this happens, the outlook is grim. Doctors have tried chemotherapy, but it makes patients ill and does not seem to help them live any longer.
Gene therapy is a possible new approach.
Anywhere between 45 and 70 percent of head and neck tumor cells have mutations in a gene known as p53, which, when normal, helps repair cancer-causing damage. ONYX-015 is an adenovirus, a relative of common cold viruses, that has been genetically engineered to attack cells that lack normal p53. This makes it technically a gene therapy drug, although unlike other gene therapy approaches ONYX-015 does not repair or replace a faulty gene, Anderson said. Last year ONYX-015 showed remarkable effects in head and neck cancer patients, but the effects did not last for long. There were side-effects.