A certified medical assistant holds needles full of the HPV vaccination drug Gardasil before administering them to children at a community health center in Texas. (Matthew Busch for The Washington Post)

The Food and Drug Administration expanded its approval of the HPV vaccine to include men and women between 27 and 45, an effort to protect more people from several types of cancer caused by the human papillomavirus.

The vaccine, called Gardasil 9, previously was approved for people ages 9 through 26. The vaccine is typically given in two doses several months apart for those who are 9 through 14, and in three doses for individuals 15 through 26. For those older than 26, the recommended regimen will be three doses.

Most sexually active individuals in the United States will become infected with HPV in their lifetimes. In most cases, the virus is cleared by the body’s immune system, but when that doesn’t occur, HPV infections can lead to cervical, anal, vaginal, penile and throat cancers.

The approval “represents an important opportunity to help prevent HPV-related diseases and cancers in a broader age range,” said Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research.

Experts say the vaccine, which protects against nine HPV strains, is most effective when administered before the initiation of sexual activity. But data also indicate that the vaccine can benefit the older group. That’s because even though many adults have been exposed to some types of HPV, most have not been exposed to all nine types covered by the vaccine.

Merck, which manufacturers the vaccine, requested the expanded age range this year. In June, the FDA granted the application priority review.

The original version of the vaccine, called simply Gardasil, was approved by the FDA in 2006 and covered four strains of HPV; it is no longer available in the United States. Gardasil 9 was approved in 2014. The two versions are manufactured similarly and cover four of the same HPV types.

The agency said it based its expanded age approval on data on the original Gardasil vaccine involving 3,200 women ages 27 through 45. The data, and long-term follow-up, showed that Gardasil was effective in preventing persistent infection, genital warts, various precancerous lesions and cancers related to HPV types covered by the vaccine. The FDA said the effectiveness for men was inferred based on the data for women, a small trial for men ages 27 through 45 and the experience of younger males.

The Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices, which is made up of medical and public health experts who make recommendations on the use of vaccines, is expected to review the expanded age range at its meeting later this month and to vote on it next year. If the CDC committee recommends that the older group receive the vaccine, insurance companies are much more likely to cover the cost.

In August, CDC data for 2017 showed that HPV vaccination rates are rising, although not as fast as medical experts would like. Nearly half of adolescents ages 13 to 17 had received all the recommended doses for HPV vaccination, while two-thirds had received the first dose. For both groups, that was a five-percentage-point increase from the previous year.

But HPV-related cancers also are increasing. More than 43,000 people developed HPV-associated cancer in 2015, compared with about 30,000 in 1999, the CDC said.

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