Thirty years after the discovery that human papillomavirus (HPV) can cause cervical cancer, 15 years after the start of vaccine development and two years after the approval of the four-type (6,11,16,18) HPV vaccine Gardasil®, vaccination to prevent cervical cancer and other HPV-related diseases has been widely implemented. Merck, the company that manufactures the vaccine is now seeking approval for the vaccine to be used in boys.
While the vaccine’s efficacy in women has been well established — with data showing up to 100% protection against HPV — studies of the vaccine’s use in men are just starting to appear. Initial data suggests that the vaccine is generally well tolerated in 9- to 26-year-old males.
Genital human papillomavirus is the most common sexually transmitted infection. There are more than 40 HPV types that can infect the genital areas of men and women, including the skin of the penis, vulva, and anus, and the linings of the vagina, cervix, and rectum. The types of HPV that can cause genital warts (6,11 – ‘low risk’) are not the same as the types that can cause cancer (16,18- ‘high risk’) but Gardasil prevents both low risk and high risk viruses.
Genital warts are a very infectious agent and transmission of the virus is very common. If a couple has unprotected sexual activities for years and one happens to be infected with genital warts, there’s a 75-percent chance of transmitting the virus to his/her partner.
Thus, vaccinating both men and women would reduce the prevalence of the virus that can be transmitted with hopes that there will be a benefit not only to men themselves but also their partners. .
While the potential benefits are encouraging, efficacy and safety must be considered in the approval of this vaccine in men.