Gardasil, one of two vaccines that fight multiple strains of human papillomavirus (HPV), was approved by Health Canada Feb 23 for use in men. But not all gay men may benefit from, or even have access to, the vaccine, medical experts point out.
And for now, those who want it must be prepared to shell out more than $400.
The vaccine, from pharma giant Merck, has been allowed in Canada for use in women since 2006, based on strong evidence it can prevent cervical and vaginal cancers and pre-cancerous lesions. The new approval, for men and boys aged 9 to 26, comes on the heels of a study presented last month showing about 75 percent effectiveness in preventing anal lesions that can lead to cancer. All study participants were men who had sex with men. (A similar study last year showed the vaccine had an even stronger effect in preventing male genital warts.)
HPV is the most common sexually transmitted infection (STI) in Canada, affecting about 75 percent of sexually active adults. Though infection often clears up on its own, when it persists, certain forms of the virus can cause genital warts — while others lead to anal, genital and oral cancers.
Men who have sex with men are about 17 times more likely to get anal cancer. And poz gay men are at much greater risk of persistent and thus more dangerous HPV infections, says Dr François Coutlée, a Montreal-based researcher and physician who specializes in diagnosing and treating anal conditions in men with HIV.
“Obviously, the men who would benefit the most from the vaccine would be those who have sex with men,” says Coutlée, who was involved in the Gardasil anal-cancer study.
But he adds that if mass vaccination is approved by public-health authorities, it would not be based on sexual orientation.
“The ideal age for vaccination is somewhere between 9 and 12, before sexual activity begins.”
What about older men — including those who are HIV-positive, who may need protection the most? The evidence of benefit is not there yet (the recent studies involved only HIV-negative men under 26), but Coutlée is optimistic.
“I would be surprised if it didn’t have any impact,” he says. Gardasil protects against four different HPV strains, he says. “The probability that you have been exposed to all four of these viruses is low.”
A Canadian study is currently underway to test the effectiveness of Gardasil in poz women, but there is still no data available for men with HIV.
Dr Benny Chang, a U of T lecturer and physician at Maple Leaf Medical Clinic whose specialties include HIV/AIDS and other STIs, is more cautious. He describes the anal-cancer study as a “small trial” but “very promising.” Still, he says the Gardasil indication for young negative men is “very good news,” especially because it can help protect women.
“We should be vaccinating all young people between the age of 9 and 26, regardless of sex or sexual orientation because at this age, there is a lower likelihood that they already have HPV infection.”
As for poz men — who are more likely than others to get anal cancer from HPV — it may simply be too late for Gardasil to be beneficial. Chang cites the work of infectious-disease expert Jeanne Marrazzo, who says most gay men with HIV already have all of the HPV strains the vaccine guards against. While Gardasil fights four types of HPV, it’s no help if you already have them. Coutlée is involved in further studies on the impact of HPV on poz men and will present results at the next international HPV conference this July in Montreal.
If you’re an HIV-negative guy under 26, speak to your doctor about Gardasil — but be prepared to open your wallet. Sheila Murphy of Merck’s vaccine division says that the Health Canada approval doesn’t automatically mean the drug will be covered by provincial health authorities for use in gay and bisexual men.
Merck is not aware of any impending changes to cover costs for men who have sex with men. “Only school-aged girls from ages 9 to 11 have their protection covered by public-health jurisdictions in Canada,” notes Murphy. She says the solution is to protest. “The gay community is very good at organizing to ensure that its needs are addressed fairly.”
A second anti-HPV vaccine, GlaxoSmithKline’s Cervarix, is available in Canada but not yet approved for use in men.