November 14, 2008

HPV Vaccine Could Prevent Male Genital Warts

A vaccine created to prevent cervical cancer in women may actually prevent genital warts in men, according to a new study by the vaccine's maker.

Experts said the results should beef up a likely bid by the vaccine's manufacturer, Merck & Co. Inc., to begin marketing the vaccine to boys.

Merck plans to ask the government for that approval later this year.

"This opens the door to a wonderful opportunity to prevent illness," said Anna Giuliano, a researcher at the H. Lee Moffitt Cancer Center in Tampa, Fla., who worked on the Merck study.

The research results were presented Thursday at a medical conference in Europe.

The focus was Merck's vaccine, Gardasil, which targets the two types of HPV, or human papillomavirus, and is given in three doses over six months.

HPV causes at least 20,000 cases of cancer in the U.S. each year. Cervical cancer is the most common type, but about a quarter of cancers occur in men, including penile, anal and even head and neck cancers.

The U.S. government licensed the vaccine for use in girls and women ages 9 to 26 during 2006.

Forty other countries have already approved the vaccine for males, but there is still no medical proof Gardasil prevents penile cancer or other HPV-associated cancers in men.

The study's results are "very exciting," but it's hard to say if they will persuade many American families to get their teenage boys vaccinated, said Dr. Maura Gillison, an HPV researcher at Johns Hopkins University.

She noted 25 percent of girls have gotten the vaccine so far, despite impressive medical studies that show the shots prevent female cancers.

"When parents are sitting in a room discussing with a pediatrician whether to vaccinate their child against anything, they'd like to know what the potential benefit is. A parent might say, 'I'm not inclined to vaccinate my child to prevent a benign genital wart,'" she said.

Government officials are eager to see additional information that may come later on the vaccine's affect on precancerous lesions, said Dr. Lauri Markowitz, an HPV expert at the U.S. Centers for Disease Control and Prevention.

"It's obviously encouraging data, but the policy makers will be looking at a variety of different issues," including how cost-effective the shot would be if used in males, said Markowitz, a medical epidemiologist.


On the Net: