Human papilloma viruses (HPV) infect the skin and mucous membranes and, although most infections cause no symptoms and are self-limiting, persistent infection can lead to warts or cancer, especially cervical cancer. HPV types are often categorized as ‘low risk’ (causing warts) or ‘high risk’ (causing cancer). Around 30-40 sub-types of the virus are sexually transmitted and the Center for Disease Control estimates that 20 million men and women are infected with HPV. Cervical cancer is estimated to kill almost 4000 women each year in the US, and 300,000 globally.
Two HPV vaccines, Gardasil® and Cervarix®, have recently been introduced to protect women against cervical cancer which is caused primarily by infection with HPV types 16 and 18. Gardasil® additionally offers protection against HPV types 6 and 11 that are most associated with warts.
Newly released results from a phase III study now show that Gardasil® prevented 90% of lesions caused by HPV types 6, 11, 16 and 18 in approximately 4000 men aged 16-26. These are the only data describing the efficacy of an HPV vaccine in preventing disease in men.