Human papillomaviruses (HPVs) are group of more than 150 related viruses, of which more than 40 of these can be easily spread through direct skin-to-skin contact. HPV infections are the most common sexually transmitted infections in the United States. High-risk HPV infection accounts for approximately 5% percent of all cancers worldwide. Persistent HPV infections with high-risk HPV types can lead to serious cytological abnormalities or lesions that, if untreated, may progress to cancer. Virtually all cervical cancers are caused by HPV infections, with just two HPV types, 16 and 18, responsible for about 70% of all cases. HPV also causes anal cancer, with about 85 percent of all cases caused by HPV-16. HPV types 16 and 18 have also been found to cause close to half of vaginal, vulvar, and penile cancers. Most recently, HPV infections have been found to cause cancer of the oropharynx, which is the middle part of the throat including the soft palate, the base of the tongue, and the tonsils. In the United States, more than half of the cancers diagnosed in the oropharynx are linked to HPV-16.
The incidence of HPV-associated oropharyngeal cancer has increased during the past twenty years, especially among men. It has been estimated that, by 2020, HPV will cause more oropharyngeal cancers than cervical cancers in the United States.
Etubics is developing an immunotherapeutic that targets E6 and E7 proteins of HPV (HPV-E6/E7). These targets are found on most HPV induced head and neck and cervical cancers. We are collaborating with Sanford Healthcare on this Program. Our preclinical studies have shown an improvement in long-term survival in animal models as well as induction of robust immune responses against HPV in vivo. When used with chemotherapy or radiation, Etubics HPV immunotherapeutic was shown to statistically enhance the clearance of established HPV cancer in vivo and largely reduced tumor growth as compared with control mice. In addition, animals having HPV induced cancers that were treated with Etubics HPV immunotherapeutic had an increase in survival as compared to animals that did not receive the agent. This data has been published in the scientific literature.