TORONTO - A federally appointed panel of experts has endorsed use of HPV vaccine in males in Canada, potentially opening the door to wider use of the vaccine in boys and young men.

Until now HPV vaccine in Canada has been recommended solely for girls and women.

The National Advisory Committee on Immunization said in a statement published online this week that the evidence is strong -- Grade A in NACI-speak -- that the vaccine protects males against a number of forms of cancer, pre-cancerous lesions and genital warts.

It recommended use of the vaccine in boys and young men aged nine to 26. It also recommended it for males over the age of nine who have sex with other men. The vaccine is not licensed for use for children of either gender under the age of nine.

The recommendation is specific to Gardasil, the HPV vaccine which protects against four strains of human papillomavirus. Gardasil is produced by drug maker Merck.

There was no recommendation regarding use in males of the competing HPV vaccine, Cervarix, which is made by GlaxoSmithKline. The NACI statement said data proving the vaccine's efficacy in males is not yet available.

Last fall, NACI's American counterpart, the Advisory Committee on Immunization Practices, voted to strongly recommend use of HPV vaccine in boys and young men.

NACI's statement said the evidence is strong that Gardasil prevents anal cancer, anogenital warts and pre-cancerous anal lesions. It said the evidence is good (Grade B) that the vaccine also protects against penile, perianal and perineal lesions and cancers.

The endorsement of the advisory panel is important for gaining public acceptance of a vaccine in Canada. But it is not a guarantee that the vaccine will automatically be added to the list of immunizations that provinces and territories provide for free.

"NACI makes recommendations that include all of the science except the cost-benefit analysis," said Dr. Allison McGeer, an infectious diseases specialist and a former member of NACI.

"A vaccine can be good and recommended and prevent disease but not be priority for new funding in health care."

The NACI statement acknowledged the cost of adding males to the existing publicly funded programs could be substantial. The vaccine is expensive. Three doses are required; a check with a downtown Toronto pharmacy shows each costs about $175.

Dr. Perry Kendall, British Columbia's chief medical officer of health, said his province has not yet had a chance to review the NACI statement or do the economic evaluation needed to determine whether it should offer the vaccine for free to males.

McGeer said the vaccine will be competing for funding consideration with others that currently are not covered by provincial and territorial programs. They include, among others, a combined vaccine to protect against measles, mumps, rubella and varicella (chickenpox), rotavirus vaccine which is not covered in all jurisdictions, and a nasal spray flu vaccine for children.

"The landscape is complicated and provincial budgets are tight," she said.