(HealthDay News) – The bivalent human papillomavirus (HPV) 16/18 vaccine is effective against oral infection, according to a study published online July 17 in PLOS ONE.
Rolando Herrero, MD, PhD, from the International Agency for Research on Cancer in Lyon, France, and colleagues randomized (1:1) 7,466 women (aged 18–25 years old) to receive either the HPV16/18 vaccine or the hepatitis A vaccine as a control. At the four-year follow-up visit, oral specimens were collected from 5,840 participants (91.9% of eligible women) to evaluate vaccine efficacy (VE) against oral infections.
The researchers found that the oral prevalence of identifiable mucosal HPV was relatively low (1.7%). At the four-year mark there were 15 prevalent HPV16/18 infections in the control group and one in the vaccine group (VE, 93.3%). For prevalent cervical HPV16/18 infection at the same visit, the VE was 72%. For other oral HPV infections there was no statistically significant protection, although these analyses were limited in their power.
“HPV prevalence four years after vaccination with the ASO4-adjuvanted HPV16/18 vaccine was much lower among women in the vaccine arm compared to the control arm, suggesting that the vaccine affords strong protection against oral HPV16/18 infection, with potentially important implications for prevention of increasingly common HPV-associated oropharyngeal cancer,” the authors write.
The vaccine was provided for the trial by GlaxoSmithKline Biologicals. Two authors are named inventors on U.S. Government-owned HPV vaccine patents.