ATLANTA (Cox News Service) -- A vaccine that prevents cervical cancer in women might also help men avoid some forms of cancer -- and an Atlanta doctor is already administering it to male patients.

Internist Dr. Scott Parry of Intown Primary Care encourages his male patients to take the vaccine against human papilloma virus, which was approved by the Food and Drug Administration last summer only for women and girls -- ages 9 to 26 years old.

For now, the FDA has not approved the vaccine for men of any age, but doctors are allowed to use the vaccine as they see appropriate. Preliminary tests by Merck, which markets the vaccine under the brand name Gardasil, seem to show it could be safe and effective in boys and young men. Clinical studies for the vaccine's use on males are still under way.

"I really push it for patients under 30," Parry said. "I encourage it for those 30 to 50."

Parry said the vaccine, which prevents many strains of genital warts, could benefit both the men who take it and their sex partners.

"Where are most women getting warts from?" he asked. "Men."

Because the human papilloma virus can lead to cancer in men, as well as women, Parry is optimistic about Gardasil's potential to ward off anal and penile cancer in his patients, many of whom are gay men. "I believe firmly in it," Parry said.

Merck spokeswoman Jennifer Allen said some studies have been done in boys and men ages 9 to 23, she said, and the company has presented a first round of results to the FDA.

"We're still in the process of collecting data," she said.

The Centers for Disease Control and Prevention has recommended administering the vaccine to young women before they become sexually active. That would also probably prove to be the best course for males, said Debbie Saslow, director of breast and gynecologic cancer for the American Cancer Society.

Interest in the vaccine has spread across the country since the FDA approved it last year because of its apparent effectiveness against the strains of HPV that cause most cases of cervical cancer.

Some state legislatures are considering making it mandatory.

Texas Gov. Rick Perry, a Republican, issued an executive order requiring the vaccine before girls will be admitted to sixth grade, but giving parents the option of refusing the vaccine for their daughters as a matter of conscience.

Some religious organizations are lobbying against the vaccine, saying it could encourage girls to have sex and that sexual abstinence will prevent transmission of the virus.

Dr. Daron Ferris, a researcher at the Medical College of Georgia in Augusta, is involved in the clinical trials of the vaccine in males. Early indications are that it could be even more effective in boys than in girls, he said.

"Little boys actually produce more antibodies than little girls do when given the vaccine," he said.

Without long-term cancer rates, researchers look at whether the body reacts to the vaccine by producing antibodies against the virus, he said.

But antibodies alone aren't enough evidence for approval, said Saslow of the American Cancer Society.

"If you have no immune response, chances are the vaccine is not going to work," she said, "but because you do, that doesn't mean the vaccine is going to work."

In addition, Saslow said, cost is a concern in any push to increase childhood vaccinations: "It's the most expensive vaccine ever, more expensive than all other childhood vaccines put together."

Because of the lack of FDA approval for use in men, insurance plans are not obligated to cover the cost of the vaccine for men.

Parry said he offers the vaccine at his cost with no markup, but it's still expensive: $130 each for three doses.

That leaves many younger men unable to afford it, Parry said.

"Therein lies the problem," he said. "The people you really want to target, under 30, have less money."

While the vaccine could be found to help all men, Ferris, the Medical College of Georgia researcher, said he understands that gay men might want the vaccine as soon as possible because some sexually active gay men face a high risk of anal cancer.

"I would be troubled if I were a gay male being told I had to wait," Ferris said.

Copyright 2007 The Cox News Service. All rights reserved.