Merck & Co, Inc announced that the US Food and Drug Administration (FDA) has approved Gardasil [Human Papillomavirus Quadrivalent (Types 6, 11, 16, and 18) Vaccine, Recombinant] for use in boys and men nine through 26 years of age for the prevention of genital warts caused by human papillomavirus (HPV) types six and 11. FDA approval is the first step in an important two-step process. The next step in the process is an Advisory Committee on Immunization Practices vote on whether to recommend administration of Gardasil for use in males, as well as public funding through the US Centers for Disease Control and Prevention (CDC) contract. These votes are expected on October 21.

"We are pleased that Gardasil is now available to help protect males," said Richard M Haupt, MPH, executive director, Merck Research Laboratories. "This is an important milestone, because the use of Gardasil can now help protect boys and girls and young men and women from certain diseases caused by this common virus." Approximately 75 to 80 per cent of people acquire one or more types of HPV at some point in their lives. For most people, the virus will go away on its own. But, for some people who don't clear certain types of the virus, HPV diseases can develop, and there is no way to predict who will or won't clear the virus. According to the CDC, certain types of HPV are associated with precancers and cancer, including cervical, vulvar, and vaginal cancers in women. In addition, other HPV types cause genital warts in both women and men.

"Nearly 17,000 new cases of genital HPV infection, of any type, occur each day in the United States, in both males and females," said Anna Giuliano, H Lee Moffitt Cancer Center, Tampa, Florida. "While most of these HPV infections clear on their own, this year alone, it is estimated that one million people in the U.S. will develop genital warts, which can cause discomfort and be distressing. Some resolve without treatment; but, for those that require treatment, warts recur in at least 25 percent of cases."

Gardasil helps protect against the four types of HPV, specifically types 6, 11, 16, and 18 that cause the most disease. It is estimated that HPV types 16 and 18 account for 70 per cent of cervical and vaginal cancer cases and up to 50 per cent of vulvar cancer cases. Types six and 11 cause approximately 90 percent of all genital warts cases.

"Education about the prevalence of HPV infection and potential disease consequences, along with the benefits and limitations of vaccination with Gardasil, is important," said Giuliano. "As with all vaccination programmes, important factors in successful implementation include patient education, along with clear communications by health care professionals."

Gardasil was approved in 2006 and is indicated for use in girls and young women nine through 26 years of age for the prevention of cervical cancer, vulvar cancer, and vaginal cancer and pre-cancers caused by HPV types 16 and 18; genital warts caused by HPV types 6 and 11; and precancerous or dysplastic lesions caused by HPV types 6, 11, 16, and 18. Gardasil is contraindicated in individuals with hypersensitivity, including severe allergic reactions to yeast, or after a previous dose of Gardasil.