Dataset Information

Early direct and indirect impact of quadrivalent HPV (4HPV) vaccine on genital warts: a systematic review.

ABSTRACT:

Introduction

Since 2007, many countries have implemented national human papillomavirus (HPV) vaccination programs with the quadrivalent HPV (4HPV) vaccine that has been shown to be efficacious in clinical trials involving 25,000 subjects. Two vaccine serotypes, HPV16 and 18, are responsible for cervical cancer and other HPV-related cancers, but the impact of the 4HPV vaccine on these cancers cannot be seen immediately as there is a considerable lag between infection with HPV and cancer development. The other two serotypes, HPV6 and 11, are responsible for genital warts (GWs), which develop within a few months after infection, making GWs an early clinical endpoint for the assessment of the impact of 4HPV vaccination.

Methods

We performed a systematic literature search in PubMed to identify all published studies on 4HPV vaccination, including those that assessed the impact of 4HPV vaccination programs on the incidence of GWs at a population level around the world.

Results

A total of 354 records were identified in the PubMed search. After screening and obtaining full papers for 56 publications, 16 publications presenting data on the impact or effectiveness of 4HPV vaccination on GWs were identified. These reported data on the impact or effectiveness of 4HPV in six countries [Australia (n = 6), New Zealand (n = 2), United States (n = 3), Denmark (n = 2), Germany (n = 1), and Sweden (n = 2)]. In Australia, no GWs were diagnosed in women aged <21 years who reported being vaccinated. A 92.6% reduction in GWs incidence was reported for all women in this age group, where the vaccine uptake rate (VUR) was 70% for 3 doses. The highest reductions were reported in countries with high VURs, mostly through school-based vaccination programs, although high VURs were obtained with some non-school-based programs.

Conclusion

The results are coherent with the GWs incidence reduction reported in clinical trials and are an early indicator of what can be expected for the long-term clinical impact on vaccine-type HPV-related cancers.

SUBMITTER: Mariani L

PROVIDER: S-EPMC4311067 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundInfection with human papillomavirus (HPV) and diseases caused by HPV are common in boys and men. We report on the safety of a quadrivalent vaccine (active against HPV types 6, 11, 16, and 18) and on its efficacy in preventing the development of external genital lesions and anogenital HPV infection in boys and men.MethodsWe enrolled 4065 healthy boys and men 16 to 26 years of age, from 18 countries in a randomized, placebo-controlled, double-blind trial. The primary efficacy objective was to show that the quadrivalent HPV vaccine reduced the incidence of external genital lesions related to HPV-6, 11, 16, or 18. Efficacy analyses were conducted in a per-protocol population, in which subjects received all three vaccinations and were negative for relevant HPV types at enrollment, and in an intention-to-treat population, in which subjects received vaccine or placebo, regardless of baseline HPV status.ResultsIn the intention-to-treat population, 36 external genital lesions were seen in the vaccine group as compared with 89 in the placebo group, for an observed efficacy of 60.2% (95% confidence interval [CI], 40.8 to 73.8); the efficacy was 65.5% (95% CI, 45.8 to 78.6) for lesions related to HPV-6, 11, 16, or 18. In the per-protocol population, efficacy against lesions related to HPV-6, 11, 16, or 18 was 90.4% (95% CI, 69.2 to 98.1). Efficacy with respect to persistent infection with HPV-6, 11, 16, or 18 and detection of related DNA at any time was 47.8% (95% CI, 36.0 to 57.6) and 27.1% (95% CI, 16.6 to 36.3), respectively, in the intention-to-treat population and 85.6% (97.5% CI, 73.4 to 92.9) and 44.7% (95% CI, 31.5 to 55.6) in the per-protocol population. Injection-site pain was significantly more frequent among subjects receiving quadrivalent HPV vaccine than among those receiving placebo (57% vs. 51%, P<0.001).ConclusionsQuadrivalent HPV vaccine prevents infection with HPV-6, 11, 16, and 18 and the development of related external genital lesions in males 16 to 26 years of age. (Funded by Merck and others; ClinicalTrials.gov number, NCT00090285.).

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