Immunogenicity and Safety of a 9-Valent HPV Vaccine

Risk factors for human papillomavirus infection and disease: A targeted literature summary

Adolescents are the primary cohort for routine human papillomavirus (HPV) vaccination, but unvaccinated adults may also benefit. A lack of consensus on which adults to target and the presence of reimbursement barriers likely contribute to the lag in adult vaccinations, highlighting missed prevention opportunities. Understanding factors contributing to risk of HPV infection and disease could help in decision making on vaccination. This review summarizes existing literature on risk factors for HPV infection and disease and includes 153 studies reporting relative risks or odds ratios for factors associated with HPV infection or disease in adults, published between 2009 and 2020. Despite inconsistent design and reporting of risk factors across studies, this review confirmed several risk factors associated with adult infection, including human immunodeficiency virus positivity, number of sex partners, and smoking. These findings can support policymaking, guideline development, and clinical decision making for HPV vaccination and screening of high-risk adult groups.

Information needs of ethnically diverse, vaccine-hesitant parents during decision-making about the HPV vaccine for their adolescent child: a qualitative study

BACKGROUND

The English schools-based human papillomavirus (HPV) vaccination programme has the potential to eliminate HPV-related cancers if high uptake is achieved. However, unmet information needs among some parents may contribute to persisting lower uptake among minority ethnic groups. Through this study we aimed to understand the information needs of vaccine-hesitant, ethnically diverse parents during decision-making about the HPV vaccine for their adolescent child, to inform the future development of tailored communication materials.

METHODS

Recruitment was facilitated thorough healthcare and community organisations within London and the South West of England. Semi-structured interviews took place between April and August 2023. Thematic analysis was undertaken, assisted by NVivo software.

RESULTS

Of the 29 parents interviewed, the majority were mothers (79%), belonged to a minority ethnic group (88%), and had an adolescent child unvaccinated against HPV (72%). Five of the interviews were undertaken in the participants' primary language with translation support. Most parents interviewed had limited knowledge about the HPV vaccine and appeared conflicted as to whether vaccines could offer benefits to health. Misunderstanding around the potential of developing serious side-effects (e.g. fertility issues, developing cancer) were factors that could negatively impact decision-making by parents. Stigma associated with the sexual transmissibility of HPV did not always negatively impact decision-making. However, some parents chose not to vaccinate on the basis of perceptions of low risk and a preference to provide education about sexual behaviours to their adolescent child.

CONCLUSIONS

Tailoring communication materials to address misunderstandings could support informed decision-making by vaccine hesitant parents for their adolescent children to be vaccinated against HPV. Future communication materials about the HPV vaccine should highlight the benefits of protection against cancer to increase parents' motivation for protect their adolescent child; provide accurate convincing information in relation to the excellent safety profile; and emphasise the importance of providing HPV vaccine at the recommended age, all alongside communicating the universality and commonality of HPV infection.

TRIAL REGISTRATION

N/A.

Ten-Year Follow-up of 9-Valent Human Papillomavirus Vaccine: Immunogenicity, Effectiveness, and Safety

BACKGROUND AND OBJECTIVES

The 9-valent human papillomavirus (9vHPV) vaccine Phase III immunogenicity study in 9- to 15-year-old boys and girls was extended to assess immunogenicity and effectiveness through 10 years after the last vaccine dose (NCT00943722).

METHODS

Boys (n = 301) and girls (n = 971) who received three 9vHPV vaccine doses in the base study (day 1, months 2 and 6) enrolled in the extension. Serum was collected through month 126 for antibody assessments by competitive Luminex immunoassay and immunoglobulin G-Luminex immunoassay. For effectiveness analysis starting at age 16 years, genital swabs were collected (to assess HPV DNA by polymerase chain reaction) and external genital examinations conducted every 6 months. Primary analyses were conducted in per-protocol populations.

RESULTS

Geometric mean antibody titers peaked around month 7, decreased sharply between months 7 and 12, then gradually through month 126. Seropositivity rates remained ≥81% by competitive Luminex immunoassay and ≥95% by immunoglobin G-Luminex immunoassay at month 126 for each 9vHPV vaccine type. After up to 11.0 (median 10.0) years of follow-up postdose 3, there were no cases of HPV6/11/16/18/31/33/45/52/58-related high-grade intraepithelial neoplasia or condyloma in males or females. Incidence rates of HPV6/11/16/18/31/33/45/52/58-related 6-month persistent infection in males and females were low (54.6 and 52.4 per 10000 person-years, respectively) and within ranges expected in vaccinated cohorts, based on previous human papillomavirus vaccine efficacy trials.

CONCLUSIONS

The 9vHPV vaccine demonstrated sustained immunogenicity and effectiveness through ∼10 years post 3 doses of 9vHPV vaccination of boys and girls aged 9 to 15 years.

Vaccinating women previously treated for human papillomavirus-related cervical precancerous lesions is highly cost-effective in China

Background

The 2021 Chinese Expert Consensus on the Clinical Application of the Human Papillomavirus (HPV) Vaccine recommended vaccination for women who previously received ablative or excisional treatment for high-grade squamous intraepithelial lesion (HSIL). This study evaluates the cost-effectiveness of HPV vaccination in women previously treated for cervical precancerous lesions.

Methods

We used a Markov model to simulate the disease progression of both low- and high-risk HPV subtypes. We followed a cohort of 100,000 women aged 18-45 years who received treatment for cervical precancerous lesions for a lifetime (80 years). We used the Incremental Cost-Effectiveness Ratios (ICER) with a 5% discount rate to measure the cost-effectiveness of nine vaccination strategies, including a combination of HPV bivalent (HPV-2), quadrivalent (HPV-4) and nonavalent vaccine (HPV-9), each with three vaccination doses (one-, two- and three-dose). We conducted one-way sensitivity analysis and probabilistic sensitivity analysis. We followed the CHEERS 2022 guidelines.

Results

Compared to the status quo, the nine vaccination strategies would result in $3.057-33.124 million incremental cost and 94-1,211 incremental quality-adjusted life-years (QALYs) in 100,000 women previously treated for cervical precancerous lesions. Three vaccination strategies were identified on the cost-effectiveness frontier. In particular, ICER for one-dose HPV-4 vaccination was US$10,025/QALY compared to the status quo (no vaccination); ICER for two-dose HPV-4 vaccination was US$17,641//QALY gained compared to one-dose HPV-4 vaccination; ICER for three-dose HPV-4 vaccination was US$27,785/QALY gained compared with two-dose HPV-4 vaccination. With a willingness-to-pay of three times gross domestic product per capita (US$37655), three-dose HPV-4 vaccination was the most cost-effective vaccination strategy compared with the lower-cost non-dominated strategy on the cost-effectiveness frontier. A probabilistic sensitivity analysis confirmed a 99.1% probability of being cost-effective. If the cost of the HPV-9 is reduced to 50% of the current price, three-dose HPV-9 vaccination would become the most cost-effective strategy.

Discussion

Three-dose HPV-4 vaccination is the most cost-effective vaccination strategy for women treated for precancerous cervical lesions in the Chinese setting.

Development and Validation of Two Optimized Multiplexed Serologic Assays for the 9-Valent Human Papillomavirus Vaccine Types

Two multiplex immunoassays are routinely used to assess antibody responses in clinical trials of the 9-valent human papillomavirus (9vHPV) vaccine. The HPV6/11/16/18/31/33/45/52/58 competitive Luminex immunoassay (HPV-9 cLIA) and HPV6/11/16/18/31/33/45/52/58 total immunoglobulin G Luminex immunoassay are used for measurements of immunogenicity. Following their initial validation in 2010, both assays were redeveloped, and several parameters were optimized, including the coating concentration of virus-like particles, type of Luminex microspheres, serum sample and reference standard diluent, reference standard starting dilution and titration series, and vendor and concentration of the phycoerythrin-labeled antibodies. Validation studies evaluated the assay performance parameters, including the intra-assay precision (repeatability), intermediate precision, linearity, relative accuracy, and limits of quantitation. In addition, since maintaining a link to the original assays that were used in trials supporting vaccine licensure is critical, the assays were formally bridged to the previous assay versions by using individual patient sera from a 9vHPV vaccine clinical trial (n = 150 day 1 [prevaccination] samples; n = 100 month 7 [1 month post-last vaccine dose] and n = 100 month 36 [30 months post-last vaccine dose; antibody persistence] samples). The results of the validation studies indicate that both optimized assays are accurate, specific, and precise over their respective quantifiable ranges. There was a strong linear association between the new and previous versions of both assays. Assay serostatus cutoffs for the redeveloped assays were established based on the bridging studies and, for the HPV-9 cLIA, further refined, based on additional data from HPV vaccine clinical studies so as to align the seropositivity rates between assay versions. IMPORTANCE Assay modernization is a key aspect of vaccine life cycle management. Thus, new, reoptimized versions of two 9vHPV immunoassays have been developed and validated for use in ongoing and future HPV vaccine clinical trials. These assays are suitable for use in high-throughput testing for HPV antibodies in serum samples. Bridging to previous versions of the assays allows for the continuous monitoring of immune responses across assay versions, including in immunogenicity studies that involve new populations as well as long-term follow-up studies.

Low-Grade Cervical Intraepithelial Neoplasia (CIN1) Evolution: Analysis of Opportunistic Preventive Vaccination Role

BACKGROUND

Low-grade cervical lesions have a high percentage of clearance in young women, even if 71-82% of low-grade intraepithelial lesion/atypical squamous cells of undetermined significance (LSIL/ASCUS) reported a High-Risk Human Papillomavirus (HR-HPV) infection, which correlates with an increased risk of Cervical Intraepithelial Neoplasia (CIN)2+. The immunogenic effect of the anti-HPV vaccine appears to be significant. The aim of the study is to evaluate the effect, two years after the diagnosis, of the anti-HPV preventive vaccination on patients with low-grade cervical lesions.

METHODS

We collected clinical, colposcopic, histological, and virological data from patients aged 21-45 years who attended the colposcopy service of the department of Obsetrics and Gynecology of IRCCS Foundation Policlinico San Matteo, Pavia, Italy. In the 2005-2019 period and had a low-grade pap-smear.

RESULTS

We enrolled 422 women consecutively, divided into two groups (vaccinated and not vaccinated) for the retrospective analysis. The rate of persistence and progression of CIN were higher in the not-vaccinated group (p = 0.019). The relative risk (RR) to develop CIN2+ during follow-up vs. the the CIN1 persistence was 1.005 (95% Confidence Interval-CI 0.961-1.051) vs. 0.994 (95% CI 0.994-1.018) for age, 3.472 (95% CI 1.066-11.320) vs. 1.266 (95% CI 0.774-2.068) for non-vaccinated, 0.299 (95% CI 0.088-1.018) vs. 0.518 (95% CI 0.242-1.109) for HIV status negative, respectively. Analyzing the time to negativity, the odds ratio (OR) was 1.012 (95% CI 1-1.024) for age and 1.591 (95% CI 1.223-2.069) for vaccination; on the other hand, considering the relationship between the time to negative and the HPV genotypes contained in the 9-valent HPV vaccines, the OR was 1.299 (95% CI 1.026-1.646) for at least one of these at recruitment and 0.631 (95% CI 0.471-0.846) at follow-up. Furthermore, the presence of at least one of the HPV genotypes targeted by the HPV nonavalent vaccine is a key indicator of the risk of progression to CIN2+: OR was 3.443 (95% CI 1.065-11.189) for the presence of at least one HPV genotype at enrollment and 5.011 (95% CI 1.899-13.224) for the presence of at least one HPV genotype at follow-up, respectively.

CONCLUSIONS

We reported in a retrospective study the benefit of anti-HPV vaccination in promoting negativity and increasing low-grade cervical lesions regression.

Immunogenicity and safety of quadrivalent and 9-valent human papillomavirus vaccines in Indian clinical trial participants

The quadrivalent human papillomavirus (qHPV; HPV6/11/16/18) and 9-valent HPV (9vHPV; HPV6/11/16/18/31/33/45/52/58) vaccines have demonstrated efficacy, immunogenicity, and safety in international clinical trials. We report outcomes from three completed clinical trials in India: a single-arm study (V501-029 [NCT00380367]) in Indian girls (aged 9-15 years; N = 110) evaluating qHPV vaccine immunogenicity and safety; a subgroup analysis (n = 225) of Indian girls/boys (9-15 years) and women (16-26 years) from a global study (V503-002 [NCT00943722]) evaluating 9vHPV vaccine immunogenicity and safety; and a qHPV vaccine post-marketing safety surveillance study (V501-125) in Indian females (aged 9-45 years; N = 188) vaccinated during routine care. In V501-029 and V503-002, HPV vaccines were administered as 3 doses (Day 1, Month 2, Month 6). Serum HPV antibodies were evaluated by competitive Luminex immunoassays at Day 1 and Month 7 (both studies) and Months 12, 24, and 36 (V503-002 only). Adverse events (AEs) were collected by Vaccination Report Card. In V501-125, participants were actively surveilled for serious AEs (SAEs) within 30 days post-qHPV vaccination. In per-protocol analyses, qHPV and 9vHPV vaccines induced robust anti-HPV6/11/16/18 (V501-029) and HPV6/11/16/18/31/33/45/52/58 (V503-002) responses, respectively; ≥97% of participants seroconverted at Month 7 for each vaccine HPV type in both studies, and antibody responses persisted through 36 months in V503-002. The most common AEs were injection-site-associated. Most AEs were mild/moderate; no deaths, vaccine-related SAEs, or discontinuations due to AEs were reported. In V501-125, no SAE was reported. Overall, the qHPV and 9vHPV vaccines elicited robust antibody responses and were generally well tolerated in Indian participants.

HPV Vaccination during the COVID-19 Pandemic in Italy: Opportunity Loss or Incremental Cost

Objectives: Italy was the first European country to introduce universal vaccination of adolescents, for both males and females, against Human Papilloma Virus (HPV) starting in 2017 with the NIP 2017–2019′s release. However, vaccine coverage rates (VCRs) among adolescents have shown a precarious take-off since the NIP’s release, and this situation worsened due to the impact of the COVID-19 pandemic in 2020. The aim of this work is to estimate the epidemiological and economic impact of drops in VCRs due to the pandemic on those generations that missed the vaccination appointment and to discuss alternative scenarios in light of the national data. Methods: Through an analysis of the official ministerial HPV vaccination reports, a model was developed to estimate the number of 12-year-old males and females who were not vaccinated against HPV during the period 2017–2021. Based on previously published models that estimate the incidence and the economic impact of HPV-related diseases in Italy, a new model was developed to estimate the impact of the aggregated HPV VCRs achieved in Italy between 2017 and 2021. Results: Overall, in 2021, 723,375 girls and 1,011,906 boys born between 2005 and 2009 were not vaccinated against HPV in Italy (42% and 52% of these cohorts, respectively). As compared with the 95% target provided by the Italian NIP, between 505,000 and 634,000 girls will not be protected against a large number of HPV-related diseases. For boys, the number of the unvaccinated population compared to the applicable target is over 615,000 in the ‘best case scenario’ and over 749,000 in the ‘worst case scenario’. Overall, between 1.1 and 1.3 million young adolescents born between 2005 and 2009 will not be protected against HPV-related diseases over their lifetime with expected lifetime costs of non-vaccination that will be over EUR 905 million. If the 95% optimal VCRs were achieved, the model estimates a cost reduction equal to EUR 529 million, the net of the costs incurred to implement the vaccination program. Conclusion: Suboptimal vaccination coverage represents a missed opportunity, not only because of the increased burden of HPV-related diseases, but also in terms of economic loss. Thus, reaching national HPV immunization goals is a public health priority.

Immunity after HPV Vaccination in Patients after Sexual Initiation

Vaccinations against human papillomavirus (HPV) are included in the primary prevention of precancerous intraepithelial lesions and HPV-related cancers. Despite the undeniable effectiveness of vaccination in the juvenile population, there is still little research on the effect in patients after sexual initiation. Our study aims to assess anti-HPV (L1 HPV) antibodies in healthy patients and diagnosed cervical pathology after 9-valent vaccination. We provide a prospective, ongoing 12-month, non-randomised pilot study in which 89 subjects were enrolled. We used an enzyme-linked immunosorbent assay to determine IgG class antibodies to HPV. We noted significantly higher levels of antibodies in vaccinated individuals than in the unvaccinated control group. The above work shows that vaccination against HPV might be beneficial in patients after sexual initiation as well as in those already diagnosed with HPV or SIL infection.

Immunogenicity and safety of the 9-valent human papillomavirus vaccine in Chinese females 9-45 years of age: A phase 3 open-label study

BACKGROUND

The 9-valent human papillomavirus (9vHPV; HPV6/11/16/18/31/33/45/52/58) vaccine was approved for use in Chinese women aged 16-26 years in 2018. This phase 3, open-label study (NCT03903562) compared 9vHPV vaccine immunogenicity and safety in Chinese females aged 9-19 years and 27-45 years with Chinese females aged 20-26 years; we report results from day 1 through 1 month post-Dose 3. The study will continue through 54 months post-Dose 3 to assess antibody persistence in Chinese girls aged 9-19 years.

METHODS

Participants aged 9-45 years received three doses of the 9vHPV vaccine. Geometric mean titers (GMTs) and seroconversion percentages for anti-HPV6/11/16/18/31/33/45/52/58 antibodies were determined by competitive Luminex immunoassay in serum samples obtained at day 1 and 1 month post-Dose 3. Adverse events (AEs) within 30 days post-vaccination and serious AEs (SAEs) occurring at any time were recorded.

RESULTS

In total, 1990 participants (690 aged 9-19 years; 650 aged 20-26 years; 650 aged 27-45 years) were enrolled. At 1 month post-Dose 3, >99% of participants in the per-protocol immunogenicity population seroconverted to each vaccine HPV type. Anti-HPV6/11/16/18/31/33/45/52/58 antibody GMTs in the 9-19-year age group were non-inferior to those in participants aged 20-26 years. Anti-HPV6/11/16/18/31/33/45/52/58 seroconversion percentages in the 27-45-year age group were non-inferior to those in participants aged 20-26 years. Injection-site and systemic AEs were reported by 43.3% and 50.9%, 50.5% and 57.1%, and 43.8% and 43.4% of participants aged 9-19, 20-26, and 27-45 years, respectively. There were no vaccine-related SAEs, discontinuations due to AEs, and deaths.

CONCLUSION

Antibody responses induced by 9vHPV vaccination in Chinese females aged 9-19 years and 27-45 years were non-inferior to those in Chinese females aged 20-26 years. The vaccine was generally well tolerated.

CLINICALTRIALS

gov Identifier: NCT03903562.

Development of a multicomponent intervention to increase parental vaccine confidence and young people's access to the universal HPV vaccination programme in England: protocol for a co-design study

INTRODUCTION

Persistent infection with HPV can result in cancers affecting men and, especially, women. Lower uptake exists by area and different population groups. Increasing parental confidence about, and adolescent access to, the universal HPV vaccination programme may help reduce inequalities in uptake. However, the evidence-base for interventions to address uptake for schools-based HPV vaccination programmes is currently lacking. This study protocol outlines how a multicomponent intervention to address this evidence gap will be codesigned with parents.

METHODS AND ANALYSIS

The proposed research will be undertaken in localities covered by two immunisation teams in London and the south-west of England. The 'person-based approach' to intervention development will be followed. In the first phase, an exploratory qualitative study will be undertaken with key stakeholders (n=8) and parents (n=40) who did not provide consent for their adolescent child to be vaccinated. During the interviews, parents' views on ways to improve parental confidence about, and adolescents' access to, HPV vaccination will be sought. The findings will be used to inform the co-design of a preliminary plan for a targeted, multicomponent intervention. In the second phase, at least two parent working groups (n=8) will be convened and will work with creative designers to co-design communication materials aimed at increasing parents' confidence in vaccination. At least two workshops with each parent group will be organised to obtain feedback on the intervention plan and communication materials to ensure they are fit for purpose. These findings will inform a protocol for a future study to test the effectiveness of the intervention at increasing HPV vaccination uptake.

ETHICS AND DISSEMINATION

The National Health Services Research Ethics Service and London School of Hygiene & Tropical Medicine Observational / Interventions Research Ethics Committee provided approvals for the study (reference 22/SW/0003 & 26902, respectively). We will work with parent advisory groups to inform our dissemination strategy and co-present our findings (eg, at community events or through social media). We will disseminate our findings with academics and healthcare professionals through webinars and academic conferences, as well as peer-reviewed publications.

Long-Term Effects of Human Papillomavirus Vaccination in Clinical Trials and Real-World Data: A Systematic Review

The preventive effect of HPV vaccines against anogenital and oropharyngeal cancers has been proven in both clinical trials and real-world data. We reviewed the published evidence about the long-term efficacy and effectiveness of the HPV vaccine in available papers of clinical trials and real-world data. As far as we searched, the longest period of preventive effect for the bivalent, 4-valent, and 9-valent vaccine were 11 years in the Costa Rica trial, 14 years in the FUTURE II, and 8 years in the LTFU extension study of V503-002 and the Scandinavian study, respectively. The sustained clinical effect during the observation period was longest for the 4-valent vaccine. In real-world data, the longest observation period of the vaccine effectiveness was 12 years in an Australian study for the 4-valent vaccine. On the other hand, the longest period of long-term persistence of HPV vaccine-induced seropositivity was 14 years in FUTURE II for the 4-valent vaccine. For the bivalent vaccine, additional long-term follow-up studies may not have been planned due to the launch of the 4-valent and 9-valent vaccines. In some studies of the 9-valent vaccine, the results have not yet been published because of the short observation period. The additional results are expected in the future. In a national immunization program, most girls and boys are inoculated with HPV vaccine by the time puberty begins; thus, it is important to monitor the vaccine effect at least until the sexually active period in their 20s and 30s.

A survey of healthcare workers’ recommendations about human papillomavirus vaccination

Purpose

The human papillomavirus (HPV) vaccine is safe and effective for preventing HPV-related diseases. However, HPV vaccination rates in Japan are low because the “Ministry of Health, Labour and Welfare” had stopped recommending vaccination. We assessed healthcare workers’ (HCWs) current recommendations regarding the HPV vaccine and how the provision of information about HPV vaccination affected their recommendations.

Materials and Methods

A survey was conducted among nurses and physicians in Nara prefecture from March 2021 to July 2021. The questionnaire asked about their understanding, recommendations, and opinions regarding HPV vaccination. Before answering the last two questions (optional), the HCWs read evidence-based information quantifying the risks and benefits of HPV vaccination.

Results

A total of 441 HCWs completed the questionnaire. Only 19% of HCWs always recommended HPV vaccination for girls aged 12–16 years. The evidence-based information significantly improved the percentage of HCWs who would “always recommend” vaccination.

Conclusion

This study showed that the proportion of HCWs who recommend HPV vaccination to adolescent girls remains low in Japan. However, we found that evidence-based information describing the causal relationship between adverse events and vaccination, quantifying the risks and benefits, noting the importance of HCW communications with families, and reporting the recommendations of national societies, might increase HCWs’ recommendations for HPV vaccination.

Design of a Phase III efficacy, immunogenicity, and safety study of 9-valent human papillomavirus vaccine in prevention of oral persistent infection in men

BACKGROUND

Seven high-risk human papillomavirus (HPV) types (16/18/31/33/45/52/58) covered by the 9-valent HPV (9vHPV) vaccine cause >90% of HPV-related head and neck cancers (HNCs). An ongoing clinical trial (NCT04199689) was designed to evaluate 9vHPV vaccine efficacy against HPV oral persistent infection, a surrogate endpoint for HPV-related HNCs.

METHODS

In this double-blind, placebo-controlled, international trial, men aged 20-45 years (N = 6000) are randomized 1:1 to receive 9vHPV vaccine or placebo on day 1, month 2, and month 6. The primary objective is to demonstrate whether 9vHPV vaccination reduces incidence of HPV16/18/31/33/45/52/58-related 6-month oral persistent infection. Incidence of HPV6/11-related 6-month oral persistent infection will be evaluated as a secondary endpoint. Oral rinse and gargle samples will be collected on day 1, month 7, month 12, and every 6 months thereafter for HPV detection by PCR. Primary analyses will be performed in per-protocol populations. Efficacy in this case-driven study will be analyzed upon accrual of ≥20 primary efficacy endpoint cases. Serum will be collected at day 1 and months 7, 12, 24, 36, and 42; anti-HPV antibody titers will be measured by competitive Luminex immunoassay. Data will be summarized as geometric mean titers and seropositivity rates. Injection-site and systemic adverse events (AEs) will be collected for 15 days post-any vaccination and serious AEs through 6 months after the last vaccination; deaths and vaccine-related serious AEs will be collected throughout the study.

DISCUSSION

This trial is expected to generate important data regarding the potential for 9vHPV vaccine to prevent HPV-related head and neck disease.

Immunogenicity and Safety of the 9-Valent Human Papillomavirus Vaccine in Solid Organ Transplant Recipients and Adults Infected With Human Immunodeficiency Virus (HIV)

BACKGROUND

The burden of human papillomavirus (HPV) in human immunodeficiency virus (HIV)-infected persons and solid organ transplant (SOT) recipients is high. Clinical trials on HPV vaccines in persons living with HIV and particularly in SOT recipients have been sparse to date, included low numbers of participants, and none of them assessed the 9-valent HPV (9vHPV) vaccine. We investigated the immunogenicity with respect to HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58 and the safety of the 9vHPV vaccine in persons living with HIV and recipients of a kidney, lung, or heart transplant.

METHODS

This is a phase III investigator-initiated study in 100 persons living with HIV (age 18-45 years) and 171 SOT recipients (age 18-55 years). The 9vHPV vaccine was administered at day 1, month 2, and month 6. Primary outcome was seroconversion rates to the 9vHPV types at month 7. Secondary outcomes were geometric mean titers (GMTs) and frequency of adverse events (AEs).

RESULTS

All HIV-infected participants seroconverted for all HPV types, but seroconversion ranged from 46% for HPV45 to 72% for HPV58 in SOT recipients. GMTs ranged from 180 to 2985 mMU/mL in HIV-positive participants and from 17 to 170 mMU/mL in SOT recipients, depending on the HPV type. Injection-site AEs occurred in 62% of participants but were mostly mild or moderate in intensity. None of the reported serious adverse events were deemed vaccine related. No patients died during the study.

CONCLUSIONS

Immunogenicity of the 9vHPV vaccine is high in persons living with HIV but suboptimal in SOT recipients. The vaccine is safe and well tolerated in both groups.

Review of long-term immunogenicity following HPV vaccination: Gaps in current knowledge

The licensed HPV vaccines are highly efficacious and induce high levels of neutralizing antibody levels, the assumed mediators of protection. However, a correlate of protection against HPV is lacking, and the evidence is still limited as to long-term persistence of antibodies, especially following reduced dosing schedules. The World Health Organization (WHO) urges immunization of young girls as part of the strategy to eliminate cervical cancer, thus long-lasting protection is required. The current review describes long-term follow-up regarding vaccine-induced seropositivity and antibody level development following the different vaccines and dosing schedules. Implications and opportunities of long-term vaccine-induced immune responses are discussed, such as the gaps in monitoring of long-term immunogenicity, the possibilities of reduced dosing schedules, and the importance of evidence for durable immunity.

Design of a Phase III immunogenicity and safety study evaluating two-dose regimens of 9-valent human papillomavirus (9vHPV) vaccine with extended dosing intervals

HPV vaccines are widely licensed as two-dose regimens, 6-12 months apart, for adolescents. Extended intervals between doses may be necessary due to resource constraints or vaccination program disruption. This international, multicenter, open-label study (NCT04708041) will evaluate the safety and immunogenicity of two-dose 9vHPV vaccine regimens with extended intervals of 1-5 years between doses in boys/girls compared with a standard three-dose regimen in women. Participants (planned N = 700) will be enrolled into six cohorts; Cohort 0: boys/girls aged 10-15 years who received one 9vHPV vaccine dose ≥1 year before enrollment without completing the series will receive one study dose of 9vHPV vaccine at day 1; Cohorts 1-4: HPV vaccination-naïve boys/girls aged 9-14 years will receive two doses (day 1 and month 12, 24, 36, or 60); Cohort 5: HPV vaccination-naïve women aged 16-26 years will receive three doses (day 1, months 2 and 6). Primary analyses will be based on serological responses 1 month after final vaccine dose. Co-primary objectives will (1) evaluate non-inferiority of geometric mean titers in each of Cohorts 1-4 versus Cohort 5, and (2) characterize antibody responses in Cohort 0, accounting for the interval between commercial and study vaccine dose. Injection-site and systemic adverse events (AEs) will be collected for 15 days and serious AEs for 12 months post-vaccination; vaccine-related serious AEs and deaths will be collected throughout the study. Results will inform completion of vaccination in individuals who did not complete the recommended series and guide implementation of vaccination programs in resource-limited settings.

Immunogenicity and safety of a nine-valent human papillomavirus vaccine in Vietnamese males and females (9 to 26 years of age): an open-label, phase 3 trial

This open-label, single-center, Phase 3 study (NCT03546842) assessed the immunogenicity and safety of the nine-valent human papillomavirus (9vHPV; HPV6/11/16/18/31/33/45/52/58) vaccine in Vietnamese males and females, with the aim to support 9vHPV vaccine licensure in Vietnam. Participants aged 9–26 years received three 9vHPV vaccine doses (Day 1, Month 2, Month 6). Serum samples were obtained on Day 1 (pre-vaccination) and at Month 7 (one month post-Dose 3) for the measurement of anti-HPV antibodies. Geometric mean titers (GMTs) and seroconversion percentages were obtained using the HPV-9 competitive Luminex immunoassay. Injection-site adverse events (AEs), systemic AEs, serious AEs (SAEs), and study discontinuations due to AEs were recorded. Of 201 participants enrolled, 200 (99.5%) received ≥1 vaccine dose. All participants who received the three-dose regimen (198/200, 98.5%) seroconverted for all 9vHPV vaccine types by Month 7. Robust anti-HPV GMT responses were also observed. Half of participants (50.5%) reported ≥1 AE; the majority were injection-site-related (45.0%) and mild (43.0%). There were no deaths, vaccine-related SAEs, or discontinuations due to AEs. Administration of three 9vHPV vaccine doses was highly immunogenic and resulted in acceptable seropositivity percentages for all vaccine HPV types. The 9vHPV vaccine was generally well tolerated among this study population.

Region of origin: Vietnam

Trial registration: clinicaltrials.gov Identifier NCT03546842

Current and future vaccine clinical research with the licensed 2-, 4-, and 9-valent VLP HPV vaccines: What's ongoing, what's needed?

Prophylactic HPV vaccination has been a great public health success. For >20 years, clinical trials were conducted with the 2-, 4-, and/or 9-valent vaccines in young-adult females, mid-adult women, males, and adolescents. In all studies, the vaccines were highly efficacious, immunogenic, and well tolerated. Following vaccine licensure and utilization in national vaccine programs globally (real-world settings primarily in high income countries), numerous studies demonstrated that the vaccines continue to have an excellent safety profile and have dramatically reduced the incidence of genital warts, HPV vaccine-type prevalence, and precancerous lesions. Thirty-eight clinical trials with the currently licensed HPV vaccines are ongoing. Key questions being addressed in new trials include: efficacy against persistent infection and immunogenicity of a 1-dose regimen; efficacy of 3 doses in 20-45-year-old females; use in postpartum women and immunocompromised individuals (HIV, liver and kidney transplants); dose sparing via intradermal administration; use in combination with a PD1 monoclonal antibody in patients with cervical cancer; impact on recurrent disease in women undergoing cervical conization; persistence of protection; and use to prevent oropharyngeal cancer. Additional clinical research that should be conducted includes: long-term follow-up, particularly of 1- and 2-dose regimens; further evaluation of flexible 2-dose regimens; immunogenicity of 1- or 2-dose regimens in persons ≥15 years old and immunocompromised populations; safety and immunogenicity of 1 or 2 doses in children <9 years old; assessment of the vaccine in the prevention of transmission; interchangeability with newer HPV vaccines; additional concomitant use studies; and prevention of penile cancer and recurrent respiratory papillomatosis.

Three-Year Follow-up of 2-Dose Versus 3-Dose HPV Vaccine

BACKGROUND AND OBJECTIVES

Human papillomavirus (HPV) antibody responses to the 9-valent human papillomavirus (9vHPV) vaccine among girls and boys (aged 9-14 years) receiving 2-dose regimens (months 0, 6 or 0, 12) were noninferior to a 3-dose regimen (months 0, 2, 6) in young women (aged 16-26 years) 4 weeks after last vaccination in an international, randomized, open-label trial (NCT01984697). We assessed response durability through month 36.

METHODS

Girls received 2 (months 0 and 6 [0, 6]: n = 301; months 0 and 12 [0, 12]: n = 151) or 3 doses (months 0,2, and 6 [0, 2, 6]: n = 301); boys received 2 doses ([0, 6]: n = 301; [0, 12]: n = 150); and young women received 3 doses ([0, 2, 6]: n = 314) of 9vHPV vaccine. Anti-HPV geometric mean titers (GMTs) were assessed by competitive Luminex immunoassay (cLIA) and immunoglobulin G-Luminex immunoassay (IgG-LIA) through month 36.

RESULTS

Anti-HPV GMTs were highest 1 month after the last 9vHPV vaccine regimen dose, decreased sharply during the subsequent 12 months, and then decreased more slowly. GMTs 2 to 2.5 years after the last regimen dose in girls and boys given 2 doses were generally similar to or greater than GMTs in young women given 3 doses. Across HPV types, most boys and girls who received 2 doses (cLIA: 81%-100%; IgG-LIA: 91%-100%) and young women who received 3 doses (cLIA: 78%-98%; IgG-LIA: 91%-100%) remained seropositive 2 to 2.5 years after the last regimen dose.

CONCLUSIONS

Antibody responses persisted through 2 to 2.5 years after the last dose of a 2-dose 9vHPV vaccine regimen in girls and boys. In girls and boys, antibody responses generated by 2 doses administered 6 to 12 months apart may be sufficient to induce high-level protective efficacy through at least 2 years after the second dose.

[Prevention of HPV-induced diseases by prophylactic vaccination]

Human papillomavirus (HPV) infections belong to the most frequent viral infections. Besides benign common warts and benign and malignant lesions of the head and neck area, HPV can induce anogenital dysplasias and cancers. Since the year 2007, effective and safe prophylactic HPV vaccines are licensed in Europe. To date, a bivalent (HPV16 and 18) and a nonavalent HPV vaccine (HPV6, 11, 16, 18, 31, 33, 45, 52, and 58) are commercially available in Germany. The German standing committee on vaccination (STIKO) currently recommends gender-neutral prophylactic HPV-vaccination between 9 and 14 years of age, with the possibility of catch-up vaccination until the age of 17 years. Besides a large proportion of HPV-induced anogenital dysplasias and carcinomas, the nonavalent HPV vaccine also prevents anogenital warts. Iatrogenically immunocompromised patients older than 17 years of age should also receive prophylactic HPV vaccination, preferrably by the age of 26 years. In case of already acquired HPV infection or existing HPV-induced lesions prophylactic vaccination does not lead to accelerated HPV elimination or clearance of lesions.

Long-term immunogenicity, effectiveness, and safety of nine-valent human papillomavirus vaccine in girls and boys 9 to 15 years of age: Interim analysis after 8 years of follow-up

BACKGROUND

The nine-valent human papillomavirus (9vHPV) vaccine protects against infection and disease related to HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. The pivotal 36-month Phase III immunogenicity study of 9vHPV vaccine in 9- to 15-year-old girls and boys was extended to assess long-term immunogenicity and effectiveness through approximately 10 years after vaccination. We describe results of an interim analysis based on approximately 8 years of follow-up after vaccination.

METHODS

Participants aged 9-15 years who received three doses of 9vHPV vaccine (at day 1, month 2, and month 6) in the base study and consented to follow-up were enrolled in the long-term follow-up study extension (N = 1272 [females, n = 971; males, n = 301]). Serum was collected at months 66 and 90 to assess antibody responses. For effectiveness analysis, genital swabs were collected (to assess HPV DNA by polymerase chain reaction [PCR]) and external genital examination was conducted (to detect external genital lesions) every 6 months starting when the participant reached 16 years of age. Cervical cytology tests were conducted annually when female participants reached 21 years of age; participants with cytological abnormalities were triaged to colposcopy based on a protocol-specified algorithm. External genital and cervical biopsies of abnormal lesions were performed, and histological diagnoses were adjudicated by a pathology panel. Specimens were tested by PCR to detect HPV DNA.

RESULTS

Geometric mean titers for each 9vHPV vaccine HPV type peaked around month 7 and gradually decreased through month 90. Seropositivity rates remained >90% through month 90 for each of the 9vHPV vaccine types by HPV immunoglobulin Luminex Immunoassay. No cases of HPV6/11/16/18/31/33/45/52/58-related high-grade intraepithelial neoplasia or genital warts were observed in the per-protocol population (n = 1107) based on a maximum follow-up of 8.2 years (median 7.6 years) post-Dose 3. Incidence rates of HPV6/11/16/18/31/33/45/52/58-related 6-month persistent infection in females and males were 49.2 and 37.3 per 10,000 person-years, respectively, which were within ranges expected in vaccinated cohorts. There were no vaccine-related SAEs or deaths during the period covered by this interim analysis.

CONCLUSIONS

The 9vHPV vaccine provided sustained immunogenicity and durable effectiveness through approximately 7 and 8 years, respectively, following vaccination of girls and boys aged 9-15 years.

Progress in Vaccination of Prophylactic Human Papillomavirus Vaccine

The human papillomavirus (HPV) vaccine plays an important role in preventing a series of diseases caused by HPV. Recent studies have shown that as a primary prevention measure, it can considerably prevent HPV infection and HPV-associated cervical cancer. However, studies on the safety, efficacy, and coverage of the HPV vaccine remain insufficient, especially in developing countries. Therefore, in this review, we outlined the recent studies of the HPV vaccine in terms of immunogenicity, safety, efficacy, latest vaccination concepts, and strategies. This review may provide a theoretical basis for use of the HPV vaccine.

[Recommendations in Male HPV from the Portuguese Society of Andrology, Sexual Medicine and Reproduction: Prevention]

The prevention of HPV-related diseases is an important healthcare issue due to its increasing incidence. Primary prevention is most important in males as it avoids initial infection and includes the use of condom, circumcision and vaccination. Primary prevention with vaccination is effective in decreasing HPV-related lesions in women up to 45 years old and the existing data for men comes from the experience from vaccinating women. Although it is the only vaccine that prevents cancer, the worldwide rates of vaccination in males is very low due to lack of information related to efficacy and side effects, lack of recommendation from the treating doctor, price and concern about encouragement of sexual promiscuity.

Adolescent and Parent Perceptions about Participation in Biomedical Sexual Health Trials

Given the burden of HIV and other sexually transmitted infections among adolescents who are legal minors, it is critical that they be included in biomedical sexual health trials to ensure that new prevention and treatment interventions are safe, effective, and acceptable for their use. However, adolescents are often not well represented in clinical trials. We provide an overview of the available evidence regarding adolescent and parent willingness for adolescents to participate in biomedical sexual health trials, parental involvement in the permission-consent process, management of differences and discord among adolescents and parents, and parental involvement throughout the study period. We also outline recommendations for current practice and areas for future research.

Safety of the 9-Valent Human Papillomavirus Vaccine

BACKGROUND

The 9-valent human papillomavirus vaccine (9vHPV) was approved for females and males aged 9 to 26 years in 2014. We analyzed postlicensure surveillance reports to the Vaccine Adverse Event Reporting System (VAERS).

METHODS

We searched VAERS data for US reports of adverse events (AEs) after 9vHPV from December 2014 through December 2017. We calculated reporting rates and conducted empirical Bayesian data mining to identify disproportional reporting. Physicians reviewed reports for selected prespecified conditions.

RESULTS

VAERS received 7244 reports after 9vHPV: 31.2% among females, 21.6% among males, and for 47.2%, sex was not reported. Overall, 97.4% of reports were nonserious. Dizziness, syncope, headache, and injection site reactions were most commonly reported; the most commonly reported AEs were similar between females and males. Two reports of death after 9vHPV were verified; no information in autopsy reports or death certificates suggested a causal relationship with vaccination. Approximately 28 million 9vHPV doses were distributed during the study period; crude AE reporting rates were 259 reports per million 9vHPV doses distributed for all reports and 7 per million doses distributed for serious reports. Syncope (a known AE associated with human papillomavirus vaccination) and several types of vaccine administration errors (eg, administered at wrong age) exceeded the statistical threshold for empirical Bayesian data mining findings.

CONCLUSIONS

No new or unexpected safety concerns or reporting patterns of 9vHPV with clinically important AEs were detected. The safety profile of 9vHPV is consistent with data from prelicensure trials and from postmarketing safety data of its predecessor, the quadrivalent human papillomavirus vaccine.

Lot-to-lot consistency study of an Escherichia coli-produced bivalent human papillomavirus vaccine in adult women: a randomized trial

An Escherichia. coli-produced HPV-16/18 bivalent vaccine has been proved to be well-tolerated and highly efficacious against diseases associated with vaccine HPV types. As a part of the multi-center, randomized, double-blind phase III clinical trial, this lot-to-lot consistency study aimed to assess the safety and immunogenicity consistency of this novel HPV vaccine, which is also one of the objectives of the phase III trial. A total of 3689 healthy women aged 18-45 years were enrolled and randomly assigned 1:1:1 to three lots of the HPV vaccine groups. The primary outcomes were the IgG antibody level at 1 month after the last dose (month 7). In the immunogenicity per-protocol set (PPS), almost all of the participants seroconverted at month 7 and remained seropositive at month 42. For each paired comparison of the three lot groups, the two-sides of 90% CIs of GMC ratios for both IgG and neutralizing antibodies for HPV-16 and HPV-18 at month 7 were within the equivalence interval [0.5, 2]. Lot consistency was also demonstrated at month 42. The majority of recorded solicited reactions were mild or moderate. The incidences of solicited reactions of Lot 2 and Lot 3 were slightly higher than Lot 1. However, the incidences of solicited reactions of ≥ grade 3 and solicited reactions by symptoms were all similar among the three lot groups. None of the SAEs was considered related to vaccination by the investigator. In conclusion, this study demonstrates lot-to-lot consistency of the 3 consecutive lots of the E. coli-produced HPV-16/18 bivalent vaccine.

Efficacy, Immunogenicity, and Safety of a 9-Valent Human Papillomavirus Vaccine: Subgroup Analysis of Participants From Asian Countries

Background

A 9-valent human papillomavirus-6/11/16/18/31/33/45/52/58 (9vHPV) vaccine extends coverage to 5 next most common oncogenic types (31/33/45/52/58) in cervical cancer versus quadrivalent HPV (qHPV) vaccine. We describe efficacy, immunogenicity, and safety in Asian participants (India, Hong Kong, South Korea, Japan, Taiwan, and Thailand) from 2 international studies: a randomized, double-blinded, qHPV vaccine-controlled efficacy study (young women aged 16–26 years; NCT00543543; Study 001); and an immunogenicity study (girls and boys aged 9–15 years; NCT00943722; Study 002).

Methods

Participants (N = 2519) were vaccinated at day 1 and months 2 and 6. Gynecological samples (Study 001 only) and serum were collected for HPV DNA and antibody assessments, respectively. Injection-site and systemic adverse events (AEs) were monitored. Data were analyzed by country and vaccination group.

Results

9vHPV vaccine prevented HPV-31/33/45/52/58–related persistent infection with 90.4%–100% efficacy across included countries. At month 7, ≥97.9% of participants seroconverted for each HPV type. Injection-site AEs occurred in 77.7%–83.1% and 81.9%–87.5% of qHPV and 9vHPV vaccine recipients in Study 001, respectively, and 62.4%–85.7% of girls/boys in Study 002; most were mild to moderate.

Conclusions

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Asian participants. Data support 9vHPV vaccination programs in Asia.

Clinical Trials Registration

NCT00543543; NCT00943722.

Seroprevalence of HPV serotypes 6, 11, 16 and 18 in unvaccinated children from Mexico City

Data regarding humoral immunity against HPV infection are scarce. Most analyses focus on the identification of viruses on mucous membranes and primarily refer to women of reproductive age. The aim of this work was to estimate the seroprevalence of antibodies against HPV serotypes 6, 11, 16 and 18 among unvaccinated boys living in Mexico City. A cross-sectional study of 257 male students from 48 public primary schools in Mexico City, whose ages fluctuated between 9 and 14 years, was carried out. Immunological status was assessed by applying the competitive Luminex Immunoassay of HPV (cLIA). Among the study population, we initially found that 38.52% (n = 99) of the children tested positive against one or more of the HPV 6, 11, 16 and/or 18 serotypes. The most commonly found serotype was isolated HPV 18 or in combination with other serotypes (22% and 31%, respectively), followed by HPV 6 with frequencies of 4.7% and 11%, respectively; however, lower frequencies were estimated for HPV 16 (2%; 6%) and isolated HPV 11, 4%. If a second set of cut-off points for seropositivity is applied, the overall prevalence for any serotype is reduced to 15.2%. As it appears that a significant sector of the study population has had basal contact with an HPV serotype, we recommend considering the possibility of vaccination against HPV at earlier ages.

Recombinant human papillomavirus nonavalent vaccine in the prevention of cancers caused by human papillomavirus

Human papillomavirus (HPV) types 16 and 18 cause 70% of cervical cancer cases globally. The nonavalent HPV vaccine (9vHPV) was licensed in 2014 and protects against the next five most common cancer-causing HPV types (HPV 31/33/45/52/58) after HPV 16/18. Phase III clinical studies have demonstrated high vaccine efficacy (>90%) against cervical, vulvar, and vaginal precancers caused by these additional types, and have shown comparable immunogenicity to the shared genotypes to quadrivalent HPV vaccine (4vHPV). Vaccine efficacy and antibody responses for 9vHPV are found to persist for at least five years while longer-term observational studies are ongoing to monitor long-term vaccine effectiveness. The implementation of 9vHPV has the potential to prevent up to 93% of cervical cancer cases, as well as a significant proportion of other HPV-related anogenital cancers. This review article summarizes the current evidence for 9vHPV in terms of vaccine efficacy against HPV infection and related anogenital precancers, safety, and immunogenicity, as well as discussing the potential impact of this vaccine on the cervical cancer burden globally.

Immunogenicity noninferiority study of 2 doses and 3 doses of an Escherichia coli-produced HPV bivalent vaccine in girls vs. 3 doses in young women

A new HPV-16/18 bivalent vaccine expressed by the Escherichia coli has been proven to be efficacious in adult women. A randomized, immunogenicity noninferiority study of this candidate vaccine was conducted in December 2015 in China. Girls aged 9–14 years were randomized to receive 2 doses at months 0 and 6 (n=301) or 3 doses at months 0, 1 and 6 (n=304). Girls aged 15–17 years (n=149) and women aged 18–26 years (n=225) received 3 doses. The objectives included noninferiority analysis of the IgG geometric mean concentration (GMC) ratio (95% CI, lower bound>0.5) to HPV-16 and HPV-18 at month 7 in girls compared with women. In the per-protocol set, the GMC ratio of IgG was noninferior for girls aged 9–17 years receiving 3 doses compared with women (1.76 (95% CI, 1.56, 1.99) for HPV-16 and 1.93 (95% CI, 1.69, 2.21) for HPV-18) and noninferior for girls aged 9–14 years receiving 2 doses compared with women (1.45 (95% CI, 1.25, 1.62) for HPV-16 and 1.17 (95% CI, 1.02, 1.33) for HPV-18). Noninferiority was also demonstrated for neutralizing antibodies. The immunogenicity of the HPV vaccine in girls receiving 3 or 2 doses was noninferior compared with that in young adult women.

Clinical guideline for 9-valent HPV vaccine: Korean Society of Gynecologic Oncology Guideline

In 2016, 9-valent human papillomavirus (HPV) vaccine has been newly introduced in Korea, thus the need to develop recommendations for the vaccine has raised. Until we decide to develop a guideline, no further studies on the bi-valent or quadri-valent HPV vaccine have been announced. We searched and reviewed the literatures focused on the efficacy of 9-valent HPV vaccine, the ideal age of 3-dose schedule vaccination, the efficacy of 9-valent HPV vaccine in middle-aged women, the efficacy of the 2-dose schedule vaccination, the safety of 9-valent HPV vaccine, the possibility of additional 9-valent HPV vaccination, and cross-vaccination of 9-valent HPV vaccine. So, Korean Society of Gynecologic Oncology (KSGO) developed a guideline only for 9-valent HPV vaccine.

Advances in Designing and Developing Vaccines, Drugs and Therapeutic Approaches to Counter Human Papilloma Virus

Human papillomavirus (HPV) is a viral infection with skin-to-skin based transmission mode. HPV annually caused over 500,000 cancer cases including cervical, anogenital and oropharyngeal cancer among others. HPV vaccination has become a public-health concern, worldwide, to prevent the cases of HPV infections including precancerous lesions, cervical cancers, and genital warts especially in adolescent female and male population by launching national programs with international alliances. Currently, available prophylactic and therapeutic vaccines are expensive to be used in developing countries for vaccination programs. The recent progress in immunotherapy, biotechnology, recombinant DNA technology and molecular biology along with alternative and complementary medicinal systems have paved novel ways and valuable opportunities to design and develop effective prophylactic and therapeutic vaccines, drugs and treatment approach to counter HPV effectively. Exploration and more researches on such advances could result in the gradual reduction in the incidences of HPV cases across the world. The present review presents a current global scenario and futuristic prospects of the advanced prophylactic and therapeutic approaches against HPV along with recent patents coverage of the progress and advances in drugs, vaccines and therapeutic regimens to effectively combat HPV infections and its cancerous conditions.

Achieving high HPV vaccine completion rates in a pediatric clinic population

Objective: To evaluate the efficacy of an intervention utilizing patient navigators (PNs) to 1) educate families on human papillomavirus (HPV) vaccination in a clinic setting and 2) provide personalized reminders for follow-up. Method: Families with 9-17 year-old children who had no record of completing the HPV vaccination series receiving primary or specialty care in 3 pediatric clinics were approached by PNs between February 1, 2015 and August 31, 2016. Demographic characteristics, visit type, preferred contact method, rates and correlates of completion, and appointments missed were analyzed. In addition, qualitative interviews of 21 providers and PNs assessed their perceptions of the program. Results: 1,391 adolescents were identified out of 2,162 patients approached as unvaccinated or partially vaccinated prior starters; among the unvaccinated, 930 received the 1st dose after being counseled by the PN (66.9%), either immediately or at a follow-up visit soon thereafter. This included 118 siblings of patients who did not have an appointment that day. Of initiators approached between 2/1/2015 and 8/31/2016, 93% (864/930) completed the series by 8/31/2017. No differences in series completion among initiators were observed by gender or race/ethnicity, but older patients (15-17 years old) were less likely to complete than 11-12 year olds. Of the 688 patients identified as prior starters, 85% completed the series through the program. Qualitative interviews demonstrated that providers felt the program addressed major barriers to HPV vaccination. Conclusion: Employing PNs dramatically increased HPV vaccine series completion among boys and girls with historically low HPV vaccination rates at pediatric clinics in Texas. Clinic providers felt this program addressed many barriers they observed prior to program implementation. This approach could markedly improve HPV vaccine series completion rates in the US.

Safety of Human Papillomavirus Vaccines: An Updated Review

Human papillomavirus (HPV) vaccines are now included in immunisation programmes in 71 countries. Unfortunately, uptake has been impacted in some countries by reduced confidence in the safety of the HPV vaccine. In 2013, we published an extensive review demonstrating a reassuring safety profile for bivalent (2vHPV) and quadrivalent (4vHPV) vaccines. A nonavalent (9vHPV) vaccine is now available and HPV immunisation programmes have been extended to males in 11 countries. The aim of this updated narrative review was to examine the evidence on HPV vaccine safety, focusing on the 9vHPV vaccine, special populations and adverse events of special interest (AESI). The previous searches were replicated to identify studies to August 2016, including additional search terms for AESI. We identified 109 studies, including 15 population-based studies in over 2.5 million vaccinated individuals across six countries. All vaccines demonstrated an acceptable safety profile; injection-site reactions were slightly more common for 9vHPV vaccine than for 4vHPV vaccine. There was no consistent evidence of an increased risk of any AESI, including demyelinating syndromes or neurological conditions such as complex regional pain or postural orthostatic tachycardia syndromes. The risk-benefit profile for HPV vaccines remains highly favourable.

A retrospective and prospective look at strategies to increase adolescent HPV vaccine uptake in the United States

The HPV vaccine debuted more than ten years ago in the United States and many strategies have been evaluated to increase HPV vaccination rates, which include not only improving current vaccination behaviors but also sustaining these behaviors. Researchers and practitioners from a variety of backgrounds have engaged in this work, which has included efforts directed at public health and government policies, health education and health promotion programs, and clinical and patient-provider approaches, as well as work aimed to respond to and combat anti-HPV vaccination movements in society. Using a previously developed conceptual model to organize and summarize each of these areas, this paper also highlights the need for future HPV vaccine promotion work to adopt a multi-level and, when possible, integrated approach in order to maximize impact on vaccination rates.

HPV vaccination and the effects on rates of HPV-related cancers

Globally, human papillomavirus (HPV) infection is one of the most common sexually transmitted infection. HPV is linked to at least five malignancies including vulvar, vaginal, anal penile, oropharyngeal, and cervical cancer. Three HPV vaccines are currently available: bivalent (HPV 16,18), quadrivalent (HPV 6,11,16,18), and nonavalent (6,11,16,18,31,33,45,52,58) targeting between 2 and 7 oncogenic HPV serotypes. This review highlights the currently epidemiologic burden of HPV-related cancers, efficacy of current HPV vaccines, and speculates about the benefits of widespread HPV vaccination. At present, all three vaccines are effective in reducing cervical disease and anogenital dysplasia in industry sponsored clinical trials and in limited study of clinical effectiveness. Models predict elimination of HPV infection with global vaccination rates of 80% and benefits in reducing malignancy at 20% global coverage. Large population-based clinical efficacy studies of these vaccines will be necessary to assess the true impact of vaccination. HPV vaccines provide a promising primary approach to preventing malignancy and barriers to vaccine access must be addressed to meet vaccination goals.

Expanded strain coverage for a highly successful public health tool: Prophylactic 9-valent human papillomavirus vaccine

Human papillomavirus is considered the causative factor for cervical cancer, which accounts for approximately 5% of the global cancer burden and more than 600,000 new cases annually that are attributable to HPV infection worldwide. The first-generation prophylactic HPV vaccines, Gardasil® and Cervarix®, were licensed approximately a decade ago. Both vaccines contain the most prevalent high-risk types, HPV16 and 18, which are associated with 70% of cervical cancer. To further increase the type coverage, 5 additional oncogenic HPV types (31, 33, 45, 52 and 58) were added to the existing Gardasil-4 to develop a 9-valent HPV vaccine (9vHPV), Gardasil 9®, increasing the potential level of protection from ∼70% to ∼90%. The efficacy of the vaccine lies primarily in its ability to elicit type-specific and neutralizing antibodies to fend off the viral infection. Therefore, type-specific and neutralizing murine monoclonal antibodies (mAbs) were used to quantitate the antigenicity of the individual vaccine antigens and to measure the antibody levels in the serum samples from vaccinees in a type- and epitope-specific manner in a competitive immunoassay. Assays for 9vHPV are extended from the proven platform used for 4vHPV by developing and adding new mAbs against the additional types. In Phase III clinical trials, comparable safety profile and immunogenicity against the original 4 types were demonstrated for the 9vHPV vaccine, and these were comparable to the 4vHPV vaccine. The efficacy of the 9vHPV vaccine was established in trials with young women. Immunobridging for younger boys and girls was performed, and the results showed higher immunogenicity in the younger age group. In a subsequent clinical trial, the 2-dose regimen of the 9vHPV vaccine used among girls and boys aged 9-14 y showed non-inferior immunogenicity to the regular 3-dose regimen for young women (aged 16-26 years). Overall, the clinical data and cost-effectiveness analysis for the 9vHPV vaccine support its widespread use to maximize the impact of this important, life-saving vaccine.

Efficacy, immunogenicity, and safety of a 9-valent human papillomavirus vaccine in Latin American girls, boys, and young women

BACKGROUND

A 9-valent human papillomavirus (HPV6/11/16/18/31/33/45/52/58; 9vHPV) vaccine was developed to expand coverage of the previously developed quadrivalent (HPV6/11/16/18; qHPV) vaccine.

METHODS

Efficacy, immunogenicity, and safety outcomes were assessed in Latin American participants enrolled in 2 international studies of the 9vHPV vaccine, including a randomized, double-blinded, controlled with qHPV vaccine, efficacy, immunogenicity, and safety study in young women aged 16-26 years, and an immunogenicity and safety study in girls and boys aged 9-15 years. Participants (N=5312) received vaccination at Day 1, Month 2, and Month 6. Gynecological swabs were collected regularly in young women for cytological and HPV DNA testing. Serum was analyzed for HPV antibodies in all participants. Adverse events (AEs) were also monitored in all participants.

RESULTS

The 9vHPV vaccine prevented HPV 31-, 33-, 45-, 52-, and 58-related high-grade cervical, vulvar, and vaginal dysplasia with 92.3% efficacy (95% confidence interval 54.4, 99.6). Anti-HPV6, 11, 16, and 18 geometric mean titers at Month 7 were similar in the 9vHPV and qHPV vaccination groups. Anti-HPV antibody responses following vaccination were higher among girls and boys than in young women. Most (>99%) 9vHPV vaccine recipients seroconverted for all 9 HPV types at Month 7. Antibody responses to the 9 HPV types persisted over 5 years. The most common AEs were injection-site related, mostly of mild to moderate intensity.

CONCLUSIONS

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Latin American young women, girls, and boys. These data support 9vHPV vaccination programs in Latin America, a region with substantial cervical cancer burden.

Prophylactic vaccination against human papillomaviruses to prevent cervical cancer and its precursors

BACKGROUND

Persistent infection with high-risk human papillomaviruses (hrHPV) types is causally linked with the development of cervical precancer and cancer. HPV types 16 and 18 cause approximately 70% of cervical cancers worldwide.

OBJECTIVES

To evaluate the harms and protection of prophylactic human papillomaviruses (HPV) vaccines against cervical precancer and HPV16/18 infection in adolescent girls and women.

SEARCH METHODS

We searched MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL) and Embase (June 2017) for reports on effects from trials. We searched trial registries and company results' registers to identify unpublished data for mortality and serious adverse events.

SELECTION CRITERIA

Randomised controlled trials comparing efficacy and safety in females offered HPV vaccines with placebo (vaccine adjuvants or another control vaccine).

DATA COLLECTION AND ANALYSIS

We used Cochrane methodology and GRADE to rate the certainty of evidence for protection against cervical precancer (cervical intraepithelial neoplasia grade 2 and above [CIN2+], CIN grade 3 and above [CIN3+], and adenocarcinoma-in-situ [AIS]), and for harms. We distinguished between the effects of vaccines by participants' baseline HPV DNA status. The outcomes were precancer associated with vaccine HPV types and precancer irrespective of HPV type. Results are presented as risks in control and vaccination groups and risk ratios (RR) with 95% confidence intervals in brackets.

MAIN RESULTS

We included 26 trials (73,428 participants). Ten trials, with follow-up of 1.3 to 8 years, addressed protection against CIN/AIS. Vaccine safety was evaluated over a period of 6 months to 7 years in 23 studies. Studies were not large enough or of sufficient duration to evaluate cervical cancer outcomes. All but one of the trials was funded by the vaccine manufacturers. We judged most included trials to be at low risk of bias. Studies involved monovalent (N = 1), bivalent (N = 18), and quadrivalent vaccines (N = 7). Most women were under 26 years of age. Three trials recruited women aged 25 and over. We summarize the effects of vaccines in participants who had at least one immunisation.Efficacy endpoints by initial HPV DNA statushrHPV negativeHPV vaccines reduce CIN2+, CIN3+, AIS associated with HPV16/18 compared with placebo in adolescent girls and women aged 15 to 26. There is high-certainty evidence that vaccines lower CIN2+ from 164 to 2/10,000 (RR 0.01 (0 to 0.05)) and CIN3+ from 70 to 0/10,000 (RR 0.01 (0.00 to 0.10). There is moderate-certainty evidence that vaccines reduce the risk of AIS from 9 to 0/10,000 (RR 0.10 (0.01 to 0.82).HPV vaccines reduce the risk of any CIN2+ from 287 to 106/10,000 (RR 0.37 (0.25 to 0.55), high certainty) and probably reduce any AIS lesions from 10 to 0/10,000 (RR 0.1 (0.01 to 0.76), moderate certainty). The size of reduction in CIN3+ with vaccines differed between bivalent and quadrivalent vaccines (bivalent: RR 0.08 (0.03 to 0.23), high certainty; quadrivalent: RR 0.54 (0.36 to 0.82), moderate certainty). Data in older women were not available for this comparison.HPV16/18 negativeIn those aged 15 to 26 years, vaccines reduce CIN2+ associated with HPV16/18 from 113 to 6 /10,000 (RR 0.05 (0.03 to 0.10). In women 24 years or older the absolute and relative reduction in the risk of these lesions is smaller (from 45 to 14/10,000, (RR 0.30 (0.11 to 0.81), moderate certainty). HPV vaccines reduce the risk of CIN3+ and AIS associated with HPV16/18 in younger women (RR 0.05 (0.02 to 0.14), high certainty and RR 0.09 (0.01 to 0.72), moderate certainty, respectively). No trials in older women have measured these outcomes.Vaccines reduce any CIN2+ from 231 to 95/10,000, (RR 0.41 (0.32 to 0.52)) in younger women. No data are reported for more severe lesions.Regardless of HPV DNA statusIn younger women HPV vaccines reduce the risk of CIN2+ associated with HPV16/18 from 341 to 157/10,000 (RR 0.46 (0.37 to 0.57), high certainty). Similar reductions in risk were observed for CIN3+ associated with HPV16/18 (high certainty). The number of women with AIS associated with HPV16/18 is reduced from 14 to 5/10,000 with HPV vaccines (high certainty).HPV vaccines reduce any CIN2+ from 559 to 391/10,000 (RR 0.70 (0.58 to 0.85, high certainty) and any AIS from 17 to 5/10,000 (RR 0.32 (0.15 to 0.67), high certainty). The reduction in any CIN3+ differed by vaccine type (bivalent vaccine: RR 0.55 (0.43 to 0.71) and quadrivalent vaccine: RR 0.81 (0.69 to 0.96)).In women vaccinated at 24 to 45 years of age, there is moderate-certainty evidence that the risks of CIN2+ associated with HPV16/18 and any CIN2+ are similar between vaccinated and unvaccinated women (RR 0.74 (0.52 to 1.05) and RR 1.04 (0.83 to 1.30) respectively). No data are reported in this age group for CIN3+ or AIS.Adverse effectsThe risk of serious adverse events is similar between control and HPV vaccines in women of all ages (669 versus 656/10,000, RR 0.98 (0.92 to 1.05), high certainty). Mortality was 11/10,000 in control groups compared with 14/10,000 (9 to 22) with HPV vaccine (RR 1.29 [0.85 to 1.98]; low certainty). The number of deaths was low overall but there is a higher number of deaths in older women. No pattern in the cause or timing of death has been established.Pregnancy outcomesAmong those who became pregnant during the studies, we did not find an increased risk of miscarriage (1618 versus 1424/10,000, RR 0.88 (0.68 to 1.14), high certainty) or termination (931 versus 838/10,000 RR 0.90 (0.80 to 1.02), high certainty). The effects on congenital abnormalities and stillbirths are uncertain (RR 1.22 (0.88 to 1.69), moderate certainty and (RR 1.12 (0.68 to 1.83), moderate certainty, respectively).

AUTHORS' CONCLUSIONS

There is high-certainty evidence that HPV vaccines protect against cervical precancer in adolescent girls and young women aged 15 to 26. The effect is higher for lesions associated with HPV16/18 than for lesions irrespective of HPV type. The effect is greater in those who are negative for hrHPV or HPV16/18 DNA at enrolment than those unselected for HPV DNA status. There is moderate-certainty evidence that HPV vaccines reduce CIN2+ in older women who are HPV16/18 negative, but not when they are unselected by HPV DNA status.We did not find an increased risk of serious adverse effects. Although the number of deaths is low overall, there were more deaths among women older than 25 years who received the vaccine. The deaths reported in the studies have been judged not to be related to the vaccine. Increased risk of adverse pregnancy outcomes after HPV vaccination cannot be excluded, although the risk of miscarriage and termination are similar between trial arms. Long-term of follow-up is needed to monitor the impact on cervical cancer, occurrence of rare harms and pregnancy outcomes.

Associations between parents' satisfaction with provider communication and HPV vaccination behaviors

BACKGROUND

Despite increasing awareness of the importance of a provider recommendation for HPV vaccine, the U.S. has yet to achieve the Healthy people 2020 goal of 80% series completion among adolescents. This failure indicates a need for further examination of the modifiable influences on parents' decision-making. Healthcare providers can influence parents' HPV vaccination decision-making, but little is known about parents' perspectives on the counseling they receive. We sought to assess U.S. parents' satisfaction with provider communication about HPV vaccine and associations with vaccination behaviors.

METHODS

Parents of 11-to-17-year-old adolescents who discussed HPV vaccination with a healthcare provider at least once (n = 795) completed our online survey in Fall 2016. We assessed their satisfaction with the discussion using the HPV Vaccine Communication Satisfaction Scale (α = 0.94). We examined associations between satisfaction (categorized as low, moderate, or high), and three vaccination behaviors: refusal/delay, series initiation (≥1 dose), and continuation (≥2 doses among initiators) using multivariable logistic regression.

RESULTS

Most parents reported high (36%) or moderate (38%) satisfaction with provider communication about HPV vaccination; fewer reported low (26%) satisfaction. Moderately satisfied parents (vs. low) had lower odds of refusal/delay (aOR = 0.59, 95% CI: 0.38-0.89), and higher odds of initiation (aOR = 1.71, 95% CI:1.15-2.55) and continuation (aOR = 2.05, 95% CI: 1.24-3.40). The associations were stronger for highly satisfied parents (refusal/delay aOR = 0.45, 95% CI: 0.29-0.70, initiation aOR = 3.59, 95% CI: 2.23-5.78, and continuation aOR = 4.08, 95% CI: 2.38-7.01).

CONCLUSIONS

Our study suggests that parent satisfaction with provider communication may play an important role in HPV vaccination decision-making. Yet, communication satisfaction has been largely unexamined in the HPV-vaccine literature to date. We introduce a brief, 7-item HPV Vaccine Communication Scale that can be used to assess parents' level of satisfaction with their provider's communication specific to HPV vaccine. We identify communication areas for providers to prioritize when discussing HPV vaccine with parents.

Tumour virus vaccines: hepatitis B virus and human papillomavirus

Two of the most important human oncogenic viruses are hepatitis B virus (HBV) and human papillomavirus (HPV). HBV infection has been preventable by vaccination since 1982; vaccination of neonates and infants is highly effective, resulting already in decreased rates of new infections, chronic liver disease and hepato-cellular carcinoma. Nonetheless, HBV remains a global public health problem with high rates of vertical transmission from mother to child in some regions. Prophylactic HPV vaccines composed of virus-like particles (VLPs) of the L1 capsid protein have been licensed since 2006/2007. These target infection by the oncogenic HPVs 16 and 18 (the cause of 70% of cervical cancers); a new vaccine licensed in 2014/2015 additionally targets HPVs 31, 33, 45, 52, 58. HPV vaccines are now included in the national immunization programmes in many countries, with young adolescent peri-pubertal girls the usual cohort for immunization. Population effectiveness in women is now being demonstrated in countries with high vaccine coverage with significant reductions in high-grade cervical intra-epithelial neoplasia (a surrogate for cervical cancer), genital warts and vaccine HPV type genoprevalence. Herd effects in young heterosexual men and older women are evident. Cancers caused by HBV and HPV should, in theory, be amenable to immunotherapies and various therapeutic vaccines for HPV in particular are in development and/or in clinical trial.This article is part of the themed issue 'Human oncogenic viruses'.

Factors that Predict Parental Willingness to Have Their Children Vaccinated against HPV in a Country with Low HPV Vaccination Coverage

Background: Adolescent HPV (Human Papilloma Virus) vaccination is yet to be introduced as a mandatory program in Poland. Polish literature on factors associated with adolescent HPV vaccination is scant, despite the fact that uptake is one of the poorest in the European Union. Objectives: To assess HPV awareness and identify independent predictors for parental willingness to have their children vaccinated against HPV. Methods: All parents of first grade students from three selected high schools in Zgorzelec, Poland, who participated in parent–teacher meetings at the time the study was conducted, had their children unvaccinated regarding HPV, and who gave informed consent to participate were included. There were 600 first grade students; 9 were vaccinated against HPV. This left 591 parents who met the eligibility criteria; the response rate was 76.1%. Results: Awareness of HPV was reported by 55.3% of 450 parents (mean age 42 years, 70.9% females); 85.1% expressed their willingness to vaccinate their children against HPV; 31.3% identified HPV as a sexually transmitted pathogen, and 36.2% identified it as a risk factor of cervical cancer. Multivariable logistic regression analyses indicated that being employed (OR 2.09; 95% CI: 1.10–3.86), having positive attitudes toward vaccines (OR 3.02; 95% CI: 1.34–6.49), previous information about HPV (OR 2.02; 95% CI: 1.17–3.51), and concerns about the side effects of the HPV vaccine (OR 0.60; 95% CI: 0.35–0.99) were independent predictors of parents’ willingness to vaccinate. Conclusions: Attitudes regarding their child being vaccinated against HPV were positive among Polish parents, even though awareness and knowledge of HPV in this group were low. Most of the significant factors that influenced their willingness were modifiable, such as being informed about HPV and having positive attitudes toward vaccines. Future interventions should focus specifically on vulnerable subgroups, such as unemployed parents.

Overcoming barriers in HPV vaccination and screening programs

The Human Papillomavirus Prevention and Control Board brought together experts to discuss optimizing HPV vaccination and screening programs. Board members reviewed the safety profile of licensed HPV vaccines based on clinical and post-marketing data, reaching a consensus that current safety data is reassuring. Successful vaccination programs used well-coordinated communication campaigns, integrating (social) media to spread awareness. Communication of evidence supporting vaccine effectiveness had beneficial effects on the perception of the vaccine. However, anti-vaccination campaigns have threatened existing programs in many countries. Measurement and monitoring of HPV vaccine confidence over time could help understand the nature and scale of waning confidence, define issues and intervene appropriately using context-specific evidence-based strategies. Finally, a broad group of stakeholders, such as teachers, health care providers and the media should also be provided with accurate information and training to help support prevention efforts through enhanced understanding of the risks and benefits of vaccination. Similarly, while cervical cancer screening through population-based programs is highly effective, barriers to screening exist: awareness in countries with population-based screening programs, access for vulnerable populations, and access and affordability in low- and middle-income countries. Integration of primary and secondary prevention has the potential to accelerate the decrease in cervical cancer incidence.

9-Valent human papillomavirus vaccine: a review of the clinical development program

INTRODUCTION

The 9-valent human papillomavirus (9vHPV) vaccine covers the same HPV types (6/11/16/18) as the quadrivalent HPV (qHPV) vaccine and 5 additional cancer-causing types (31/33/45/52/58). Epidemiological studies indicate that the 9vHPV vaccine could prevent approximately 90% of cervical cancers, 70-85% of high-grade cervical dysplasia (precancers), 85-95% of HPV-related vulvar, vaginal, and anal cancers, and 90% of genital warts. Areas covered: Study design features and key findings from the 9vHPV vaccine clinical development program are reviewed. In particular, 9vHPV vaccine efficacy was established in a Phase III study in young women age 16-26 years. Efficacy results in young women were extrapolated to pre- and young adolescent girls and boys and young men by immunological bridging (i.e., demonstration of non-inferior immunogenicity in these groups versus young women). Expert commentary: The development of the 9vHPV vaccine is the outcome of 20 years of continuous clinical research. Broad vaccination programs could help substantially decrease the incidence of HPV-related disease.

Adolescent Participation in HPV Vaccine Clinical Trials: Are Parents Willing?

Approximately one-quarter of human papillomavirus (HPV) infections are acquired by adolescents, with a higher burden among racial/ethnic minorities. However, racial/ethnic minorities have been underrepresented in previous HPV vaccine trials. Ongoing and future HPV vaccine optimization trials would benefit from racially- and ethnically-diverse sample of adolescent trial participants. This study examined factors influencing parental willingness to consent to their adolescents' participation in HPV vaccine clinical trials and tested for possible racial differences. A convenience sample of parents of adolescents (N = 256) completed a cross-sectional survey. Chi square analyses were used to assess racial differences in parental HPV vaccine awareness and intentions and willingness to consent to their child participating in an HPV vaccine clinical trial. Ordinal logistic regression was used to identify factors associated with willingness. Approximately 47% of parents were willing to allow their adolescent to participate in HPV vaccine clinical trials (30.7% African American and 48.3% Caucasian, p = .081). African Americans had lower HPV vaccine awareness (p = .006) but not lower intentions to vaccinate (p = .086). Parental willingness was positively associated with the following variables: Child's age (p < .039), Perceived Advantages of HPV Vaccination for Adolescents (p = .002), Parental Trust in Medical Researchers (p < .001), and Level of Ease in Understanding Clinical Trial Information (p = .010). Educating parents about the advantages of HPV vaccines for younger adolescents using low-literacy educational materials and building trust between parents and researchers may increase parental willingness to consent to adolescent participation in HPV vaccine clinical trials.

Population-based HPV vaccination programmes are safe and effective: 2017 update and the impetus for achieving better global coverage

Persistent oncogenic human papillomavirus (HPV) is the cause of cervical cancer, as well as cancers of the anus, penis, vulva, vagina and oropharynx. There is good evidence that prophylactic HPV vaccines are immunogenic and effective against targeted-type HPV infections and type-specific genital lesions, including high-grade cervical intraepithelial neoplasia (CIN), when administered prior to HPV infection. There is good evidence that HPV vaccines are safe in population usage, with the most frequent adverse event being injection-site reactions. There is evidence to support some cross-protection against non-targeted types occurring following the administration of HPV vaccines. There is limited evidence suggesting that HPV vaccines may be beneficial in preventing future disease in women treated for high-grade CIN. This chapter focuses on the accumulated evidence regarding the global use of the three licensed HPV vaccines including safety, immunogenicity, duration of protection, effectiveness, coverage to date and barriers to higher coverage.