Children ages 9 to 14 years old will now need one less dose of the vaccine against human papillomavirus (HPV), according to new recommendations from the CDC.
Under the new recommendations, boys and girls between the ages of 9 and 14 can now receive two doses of HPV vaccine, given six to twelve months apart. Previously, the CDC had recommended a three-dose regimen.
Patients aged 15 to 26—and those who are immunocompromised—should still receive three doses of the vaccine.
The 9-valent HPV vaccine protects patients against nine different types of the virus including HPV 16 and HPV 18, the two forms that have been found to cause the majority of HPV-associated cancers, which include cervical, vaginal, and vulvar cancers in women and penile cancer in men. Both men and women can develop oropharyngeal cancer, anal cancer, and genital warts as a result of infection with HPV, which is said to infect 79 million Americans.
The CDC made the recommendation to reduce the number of doses in younger patients after a nearly year-long effort by the Advisory Committee on Immunization Practices (ACIP) HPV Vaccines Work Group. The group reviewed and evaluated the efficacy and effectiveness data of a two-dose schedule. It weighed the potential benefits and harms of the reduced schedule, considered patient preferences, and studied health economic analyses before it reached a conclusions.
According to the CDC, the decision to switch to a two-dose regimen for children between ages 9 and 14 was made partly on the basis of findings from a clinical trial that found two doses of vaccine were as effective as three in that population.
That trial, led by Ole-Erik Iversen, a professor at the University of Bergen in Norway, was conducted at 52 ambulatory care sites across 15 different countries and compared two doses of the vaccine administered six months apart, two doses administered twelve months apart, and three doses administered within six months.
"The most important finding was that the simpler schedule gave non-inferior antibody responses," Iversen said.
The advantage of the two-dose regimen, he said, is that it reduces the number of injections needed and also has significant cost implications. A three-dose regimen is 50% more expensive both in terms of the cost of the vaccine and additional resources and supplies.
"In other words, [it's] a benefit to all involved—the taxpayer included," he said.