According to US researchers, vaccinating boys against cervical cancer and genital warts virus does not appear to be cost-effective, as assuming all girls are given the shot, giving the boys the same may not be worth the expense.

The U. S. Food and Drug Administration (FDA) is weighing whether Gardasil, Merck & Co.'s vaccine against human papillomavirus should be given approval for use in men and boys between the ages of 9 to 26-years, offering them protection against, including preventing them from spreading the virus to their sexual partners.

Jane Kim, whose study appears in the British Medical Journal, believes the results of her study imply better use of resources expended and other health interventions being more useful in increasing population health gains.

The U. S. Centres for Disease Control and Prevention (CDC) recommends, Gardasil, approved for use in girls and young women as protection against certain virus strains, be given to 11 and
12-year-old girls and women aged 13 to 26-years, who have not received the vaccination.

Global sales of the vaccine totaled $1.4-billion in 2008, with an additional $865-million via a joint venture with Sanofi-Aventis, however, growth has slowed in markets where the initial group of eligible teenage girls has been immunized.

Falling sales may be the reason why Merck is now seeking approval for its use in boys and men, as clinical trials show the vaccine to offer a high degree of protection.

However, the current study found using the vaccine on girls was good value, however, adding boys to the equation did not see benefits outweighing costs.

The study findings do not suggest FDA should not give its approval to the vaccine for boys, as since, the vaccine is new, all the health benefits of giving it to boys are not fully known, though the study does say it might not be cost-effective to recommend routine vaccination in boys.

Gardasil, approved for girls in 2006 covers four types of HPV, two of which cause about 70% of cervical cancers worldwide.

Since, the vaccine was approved, studies have found it to be safe and nearly 100% effective in preventing precancerous cervical lesions from four HPV strains the vaccine targets. They have also shown Gardasil to be far more effective when given to girls or young women before they become sexually active.