Merck & Co., Inc. announced that Health Canada has approved an expanded indication of GARDASIL in individuals 9 through 45 years of age for the prevention of infection caused by the Human Papillomavirus types 6, 11, 16, 18, 31, 33, 45, 52 and 58 and the following diseases associated with the HPV types included in the vaccine: Oropharyngeal and other head and neck cancers caused by HPV types 16, 18, 31, 33, 45, 52, and 58. This market authorization has been issued with conditions pending the results of trials to verify its clinical benefit. It is estimated that 75% of sexually active Canadians will have an HPV infection at some point if not immunized and that more than 550,000 Canadians become infected with HPV each year.

While most infected people clear the virus, those who do not can develop HPV-related cancers and precancers, or genital warts. Many people who have HPV may not show any signs or symptoms, which means they can infect others without knowing it. According to the Public Health Agency of Canada, about 25% to 35% of mouth and throat cancers are related to oral HPV infection and in 2012, the incidence rate of HPV-associated oropharyngeal cancer was more than 4.5 times higher in males and females.

The proportion of tonsillar cancers in Canada in which HPV has been detected increased from 25% to 62%. GARDASIL is a vaccine indicated for individuals 9 through 45 years of age for the prevention of infection caused by the Human Papillomavirus types 6, 11, 16, 18, 31, 33, 45, 52 and 58 and the following diseases associated with the HPV types included in the vaccine: cervical, vulvar, vaginal, and anal cancer (without conditions), and oropharyngeal and other head and neck cancers (with conditions) caused by HPV types 16, 18, 31, 33, 45, 52, and 58; genital warts caused by HPV types 6 and 11; and the following precancerous or dysplastic lesions caused by HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58: cervical adenocarcinoma in situ, cervical intraepithelial neoplasia grade 2 and grade 3, cervical intraepithelial neoplasia grade 1, vulvar intraepithelial neoplasia grade 2 and grade 3, vaginal intraepithelial neoplasia grade 2 and grade 3, and anal intraepithelial neoplasia grades 1, 2, and 3. The oropharyngeal and other head and neck cancer indication for GARDASIL has been issued market authorization with conditions, pending the results of trials to verify its clinical benefit. Healthcare practitioners should advise patients of the nature of the authorization.

Health Canada's approval for the prevention of HPV-related oropharyngeal and other head and neck cancers caused by HPV types 16, 18, 31, 33, 45, 52 and 58 is based on the effectiveness of GARDASIL and GARDASIL to prevent persistent infection and anogenital disease caused by HPV types covered by the vaccine. GARDASIL should not be used in anyone with an allergic reaction to a previous dose of GARDASIL or GARDASIL or to any of the ingredients in the vaccine. GARDASIL does not treat HPV infection and may not protect everyone who gets vaccinated.

Side effects and allergic reactions can occur.14 GARDASIL is not recommended for use in pregnant women.