Potential impact of a nine-valent vaccine in human papillomavirus related cervical disease

Update on the new 9-valent vaccine for human papillomavirus prevention

OBJECTIVE

To provide family physicians with information on the efficacy, safety, public health effects, and cost-effectiveness of the 9-valent human papillomavirus (HPV) vaccine.

QUALITY OF EVIDENCE

Relevant publications in PubMed up to May 2015 were reviewed and analyzed. Most evidence cited is level I (randomized controlled trials and meta-analyses) or level II (cross-sectional, case-control, and epidemiologic studies). Government reports and recommendations are also referenced.

MAIN MESSAGE

The 9-valent HPV vaccine, which protects against HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58, is safe and effective and will further reduce the incidence of HPV infection, as well as HPV-related cancers. It can also indirectly protect unvaccinated individuals through herd immunity. With an effective vaccination program, most cervical cancers can be prevented. Analyses show that the cost-effectiveness of the 9-valent HPV vaccine in female patients is comparable to the original quadrivalent HPV vaccine (which protects against HPV types 6, 11, 16, and 18) currently in use. However, the usefulness of vaccinating male patients with the 9-valent HPV vaccine needs further investigation.

CONCLUSION

The 9-valent HPV vaccine offers more protection against HPV than the quadrivalent HPV vaccine does and is as safe. Analysis of cost-effectiveness favours its use, at least in adolescent girls. Therefore, physicians should recommend the 9-valent HPV vaccine to patients instead of the quadrivalent HPV vaccine.

Phase II studies to select the formulation of a multivalent HPV L1 virus-like particle (VLP) vaccine

Our objective was to develop a multivalent prophylactic HPV vaccine that protects against infection and disease caused by HPV16/18 (oncogenic types in existing prophylactic vaccines) plus additional oncogenic types by conducting 3 Phase II studies comparing the immunogenicity (i.e., anti-HPV6/11/16/18 geometric mean titers [GMT]) and safety of 7 vaccine candidates with the licensed quadrivalent HPV6/11/16/18 vaccine (qHPV vaccine) in young women ages 16-26. In the first study (Study 1), subjects received one of 3 dose formulations of an 8-valent HPV6/11/16/18/31/45/52/58 vaccine or qHPV vaccine (control). In Study 2, subjects received one of 3 dose formulations (termed low-, mid-, and high-dose formulations, respectively) of a 9-valent HPV6/11/16/18/31/33/45/52/58 vaccine (9vHPV vaccine) or qHPV vaccine (control). In Study 3, subjects concomitantly received qHPV vaccine plus 5-valent HPV31/33/45/52/58 or qHPV vaccine plus placebo (control). All vaccines were administered at day 1/month 2/month 6. In studies 1 and 3, anti-HPV6/11/16/18 GMTs at month 7 were non-inferior in the experimental arms compared with the control arm; however, there was a trend for lower antibody responses for all 4 HPV types. In Study 2, this immune interference was overcome with the mid- and high-dose formulations of the 9vHPV vaccine by increasing antigen and adjuvant doses. In all 3 studies, all vaccine candidates were strongly immunogenic with respect to HPV31/33/45/52/58 and were well tolerated. Based on the totality of the results, the middle dose formulation of the 9vHPV vaccine was selected for Phase III evaluation. Each 0.5mL dose contains 30μg/40μg/60μg/40μg/20μg/20μg/20μg/20μg/20μg of HPV6/11/16/18/31/33/45/52/58 virus-like particles, and 500μg of amorphous aluminum hydroxyphosphate sulfate adjuvant.ClinicalTrials.gov numbers NCT00260039, NCT00543543, and NCT00551187.

Prevalence of HPV After Introduction of the Vaccination Program in the United States

BACKGROUND

Since mid-2006, human papillomavirus (HPV) vaccination has been recommended for females aged 11 to 12 years and through 26 years if not previously vaccinated.

METHODS

HPV DNA prevalence was analyzed in cervicovaginal specimens from females aged 14 to 34 years in NHANES in the prevaccine era (2003-2006) and 4 years of the vaccine era (2009-2012) according to age group. Prevalence of quadrivalent HPV vaccine (4vHPV) types (HPV-6, -11, -16, and -18) and other HPV type categories were compared between eras. Prevalence among sexually active females aged 14 to 24 years was also analyzed according to vaccination history.

RESULTS

Between the prevacccine and vaccine eras, 4vHPV type prevalence declined from 11.5% to 4.3% (adjusted prevalence ratio [aPR]: 0.36 [95% confidence interval (CI): 0.21-0.61]) among females aged 14 to 19 years and from 18.5% to 12.1% (aPR: 0.66 [95% CI: 0.47-0.93]) among females aged 20 to 24 years. There was no decrease in 4vHPV type prevalence in older age groups. Within the vaccine era, among sexually active females aged 14 to 24 years, 4vHPV type prevalence was lower in vaccinated (≥1 dose) compared with unvaccinated females: 2.1% vs 16.9% (aPR: 0.11 [95% CI: 0.05-0.24]). There were no statistically significant changes in other HPV type categories that indicate cross-protection.

CONCLUSIONS

Within 6 years of vaccine introduction, there was a 64% decrease in 4vHPV type prevalence among females aged 14 to 19 years and a 34% decrease among those aged 20 to 24 years. This finding extends previous observations of population impact in the United States and demonstrates the first national evidence of impact among females in their 20s.

An overview of new biomolecular pathways in pathogen-related cancers

Cancer molecular pathways are combinations of metabolic processes deregulated in neoplastic cells. Besides pathways specific to tissues from which cancers originate, common neoplastic traits are present among most tumors. Hanahan and Weinberg have described the most critical 'hallmarks' shared by many cancer types. In recent years, cancer stem cell specific properties and pathways have also been identified. Other altered pathways are peculiar of cancer type and cancer stage, even in different cancer stem cell types. In pathogen-related tumors, the alteration of inflammatory and immunologic response along with impairment of cell cycle control represents key molecular events of tumor progression. This article summarizes the recent discoveries of new altered pathways in cancer and their importance in cancer diagnosis and tailored therapies.

Lessons learned from successful human vaccines: Delineating key epitopes by dissecting the capsid proteins

Recombinant VLP-based vaccines have been successfully used against 3 diseases caused by viral infections: Hepatitis B, cervical cancer and hepatitis E. The VLP approach is attracting increasing attention in vaccine design and development for human and veterinary use. This review summarizes the clinically relevant epitopes on the VLP antigens in successful human vaccines. These virion-like epitopes, which can be delineated with molecular biology, cryo-electron microscopy and x-ray crystallographic methods, are the prerequisites for these efficacious vaccines to elicit functional antibodies. The critical epitopes and key factors influencing these epitopes are discussed for the HEV, HPV and HBV vaccines. A pentamer (for HPV) or a dimer (for HEV and HBV), rather than a monomer, is the basic building block harboring critical epitopes for the assembly of VLP antigen. The processing and formulation of VLP-based vaccines need to be developed to promote the formation and stabilization of these epitopes in the recombinant antigens. Delineating the critical epitopes is essential for antigen design in the early phase of vaccine development and for critical quality attribute analysis in the commercial phase of vaccine manufacturing.

Morbidity and mortality of vulvar and vaginal cancers: Impact of 2-, 4-, and 9-valent HPV vaccines

Vaginal and vulvar cancers do not account for a large proportion of gynecologic malignancies but their impact is significant. Both vaginal and vulvar lesions have precursors and display levels of dysplasia before progression to invasive disease. Human Papillomavirus (HPV) is a known causative agent of such dysplasia and can be detected now more readily than ever with adequate recognition techniques and provider awareness. Although HPV vaccination is still lagging compared to other recommended childhood vaccinations, the impact on lower genital tract neoplasia is promising. The bivalent and quadrivalent vaccines have been shown to be efficacious and the newest nonavalent vaccine should add even more of impact on coverage of cancer-causing HPV types. Although it is still early to show true clinical and population-based disease reduction due to low disease incidence and relatively short time of vaccine availability, the potential is noteworthy.

Cervical Cancer Screening in Partly HPV Vaccinated Cohorts - A Cost-Effectiveness Analysis

Background

Vaccination against the oncogenic human papillomavirus (HPV) types 16 and 18 will reduce the prevalence of these types, thereby also reducing cervical cancer risk in unvaccinated women. This (measurable) herd effect will be limited at first, but is expected to increase over time. At a certain herd immunity level, tailoring screening to vaccination status may no longer be worth the additional effort. Moreover, uniform screening may be the only viable option. We therefore investigated at what level of herd immunity it is cost-effective to also reduce screening intensity in unvaccinated women.

Methods

We used the MISCAN-Cervix model to determine the optimal screening strategy for a pre-vaccination population and for vaccinated women (~80% decreased risk), assuming a willingness-to-pay of €50,000 per quality-adjusted life year gained. We considered HPV testing, cytology testing and co-testing and varied the start age of screening, the screening interval and the number of lifetime screens. We then calculated the incremental cost-effectiveness ratio (ICER) of screening unvaccinated women with the strategy optimized to the pre-vaccination population as compared to with the strategy optimized to vaccinated women, assuming different herd immunity levels.

Results

Primary HPV screening with cytology triage was the optimal strategy, with 8 lifetime screens for the pre-vaccination population and 3 for vaccinated women. The ICER of screening unvaccinated women 8 times instead of 3 was €28,085 in the absence of herd immunity. At around 50% herd immunity, the ICER reached €50,000.

Conclusion

From a herd immunity level of 50% onwards, screening intensity based on the pre-vaccination risk level becomes cost-ineffective for unvaccinated women. Reducing the screening intensity of uniform screening may then be considered.

Deconstructing the measure of vaccine efficacy against disease irrespective of HPV in HPV vaccine clinical trials

BACKGROUND

Human papillomavirus (HPV) vaccines were licensed by demonstrating prevention of anogenital disease caused by specific HPV types in clinical studies. Measuring the impact of HPV vaccination on the overall burden of anogenital disease (irrespective of HPV) is an important public health question which is ideally addressed in post-licensure epidemiological studies. Attempts were made to use clinical trial data for that purpose. However, the interpretation of vaccine efficacy on the endpoint of disease irrespective of HPV is not widely understood.

METHODS

We used the 9-valent HPV vaccine clinical program as a case study to determine the value of measuring vaccine efficacy in such endpoint. This assessment was rigorously performed by heuristic reasoning and through probability calculations.

RESULTS

The measure of vaccine efficacy in the irrespective of HPV endpoint is driven simultaneously in opposite directions by the high estimate of prophylactic efficacy and a numerically negative estimate of risk reduction that is also a reflection of high prophylactic efficacy and no cross-protection.

CONCLUSIONS

The vaccine efficacy estimate in the irrespective of HPV endpoint is ambiguous and difficult to interpret. Comparing this estimate across different HPV vaccine studies requires an understanding of the contributions of vaccine HPV type efficacy and the incidence of disease not related to vaccine HPV types for each study. Without such understanding, comparing studies and drawing conclusions from such comparison are highly misleading. Approaches are proposed to divide this endpoint in components that are easier to interpret.

Secular trends of HPV genotypes in invasive cervical cancer in Cali, Colombia 1950-1999

Aim To estimate relative contribution and time trends of HPV types in cervical cancer in Cali, Colombia over a 50 years' period.

METHODS

Paraffin blocks of 736 cervical cancer histological confirmed cases were retrieved from the pathology laboratory at Hospital Universitario del Valle (Cali, Colombia) and HPV genotyped using SPF10-PCR/DEIA/LiPA25 (version 1) assay. Marginal effect of age and year of diagnosis in secular trends of HPV type prevalence among HPV+ cases were assessed by robust Poisson regression analysis.

RESULTS

64.7% (95%CI: 59.9-69.2) of squamous cell carcinomas (SCCs) were attributed to HPV 16 and 18, 78.2% (95%CI: 74-82) to HPV 16, 18, 31, 33 and 45 and 84.8% (95%CI: 81-88.1) to HPV 16, 18, 31, 33, 45, 52 and 58 while ninety-three percent of adenocarcinomas (ADCs) were attributed to HPV 16, 18 and 45 only. The prevalence of specific HPV types did not change over the 50-year period. A significant downward trend of prevalence ratios of HPV16 (​P=0.017) and α7 but HPV 18 (i.e., HPV 39, 45, 68, 70, ​P=0.024) with increasing age at diagnosis was observed. In contrast, the prevalence ratio to other HPV genotypes of α9 but HPV 16 genotypes (i.e., HPV 31, 33, 35, 52, 58, 67, ​P=0.002) increased with increasing age at diagnosis.

CONCLUSION

No changes were observed in the relative contribution of HPV types in cervical cancer in Cali, Colombia during the 50 years. In this population, an HPV vaccine including the HPV 16, 18, 31, 33, 45, 52 and 58 genotypes may have the potential to prevent ∼85% and 93% of SCC and ADC cases respectively.

Seroprevalence of 9 Human Papillomavirus Types in the United States, 2005-2006

BACKGROUND

A 9-valent human papillomavirus (HPV) vaccine, licensed in 2014, prevents 4 HPV types targeted by the quadrivalent vaccine (6/11/16/18) and 5 additional high-risk (HR) types (31/33/45/52/58). Measuring seropositivity before vaccine introduction provides baseline data on exposure to types targeted by vaccines.

METHODS

We determined seroprevalence of HPV 6/11/16/18/31/33/45/52/58 among 4943 persons aged 14-59 years who participated in the National Health and Nutrition Examination Survey, 2005-2006.

RESULTS

Among females, seroprevalence was 40.5% for any of the 9 vaccine types, 30.0% for any 7 HR types (16/18/31/33/45/52/58), 19.0% for any 5 additional types (31/33/45/52/58), and 18.3% for 16/18. Compared with non-Hispanic whites, non-Hispanic blacks had higher seroprevalence of 31/33/45/52/58 (36.8% vs 15.9%) and 16/18 (30.1% vs 17.8%), while Mexican Americans had higher seroprevalence of 31/33/45/52/58 (23.6% vs 15.9%) (P < .05 for all). In multivariable analyses of data from females, race/ethnicity, number of sex partners, and age were associated with 16/18 and 31/33/45/52/58 seropositivity. Seropositivity was lower among males than among females (P < .001 for all type categories).

CONCLUSIONS

In 2005-2006, about 40% of females and 20% of males had serological evidence of exposure to ≥1 of 9 HPV types. Seroprevalence of all type categories, especially HPV 31/33/45/52/58 among females, varied by race/ethnicity.

Functional assessment and structural basis of antibody binding to human papillomavirus capsid

Persistent high-risk human papillomavirus (HPV) infection is linked to cervical cancer. Two prophylactic virus-like particle (VLP)-based vaccines have been marketed globally for nearly a decade. Here, we review the HPV pseudovirion (PsV)-based assays for the functional assessment of the HPV neutralizing antibodies and the structural basis for these clinically relevant epitopes. The PsV-based neutralization assay was developed to evaluate the efficacy of neutralization antibodies in sera elicited by vaccination or natural infection or to assess the functional characteristics of monoclonal antibodies. Different antibody binding modes were observed when an antibody was complexed with virions, PsVs or VLPs. The neutralizing epitopes are localized on surface loops of the L1 capsid protein, at various locations on the capsomere. Different neutralization antibodies exert their neutralizing function via different mechanisms. Some antibodies neutralize the virions by inducing conformational changes in the viral capsid, which can result in concealing the binding site for a cellular receptor like 1A1D-2 against dengue virus, or inducing premature genome release like E18 against enterovirus 71. Higher-resolution details on the epitope composition of HPV neutralizing antibodies would shed light on the structural basis of the highly efficacious vaccines and aid the design of next generation vaccines. In-depth understanding of epitope composition would ensure the development of function-indicating assays for the comparability exercise to support process improvement or process scale up. Elucidation of the structural elements of the type-specific epitopes would enable rational design of cross-type neutralization via epitope re-engineering or epitope grafting in hybrid VLPs.

Estimation of the epidemiological burden of HPV-related anogenital cancers, precancerous lesions, and genital warts in women and men in Europe: Potential additional benefit of a nine-valent second generation HPV vaccine compared to first generation HPV vaccines

Introduction

A second generation HPV vaccine has been developed for the prevention of anogenital cancers and precancerous lesions of the cervix, vulva, vagina, anus and of genital warts due to nine HPV types.

We estimated the annual burden of these diseases attributable to the nine HPV types compared to HPV types from first generation vaccines in women and men in Europe.

Material and methods

Incidence rates from the IARC database, cancer registries, the literature and Eurostat population data were used.

The burden attributable to the HPV types targeted by both vaccines was estimated by applying the relative contribution of the respective HPV types from epidemiological studies.

Results

In 2013, the number of new anogenital HPV-attributable cancers was 44,480 with 39,494 of these cases related to second vs. 33,285 to first generation vaccine types.

Among the 284,373 to 541,621 new HPV-attributable anogenital precancerous lesions 235,364–448,423 and 135,025–256,830 were estimated to be related to second and first generation vaccine types, respectively.

The annual number of new genital warts was 753,608–935,318, with 90% related to HPV6/11.

Conclusions

These data demonstrate how the large public health impact that was achieved by the first generation HPV vaccines could be further increased by second generation vaccines.

Monitoring for Extra-Intestinal Cancers in IBD

Multiple studies have demonstrated an increased risk for extra-intestinal cancers in inflammatory bowel disease (IBD) patients, mainly from treatment modalities. Prominent cancers that are related to IBD treatment include the following: lymphoproliferative disorders associated with thiopurine use, hepatosplenic T cell lymphoma primarily in younger male patients on thiopurines and anti-tumor necrosis factor (TNF) agents, non-melanoma skin cancers in patients treated with thiopurines and anti-TNF agents, and melanomas in patients who are on monotherapy with anti-TNF agents. In addition, women with IBD may have higher rates of cervical dysplasia and cervical cancer. The focus of this review is to provide a comprehensive overview on extra-intestinal cancers in IBD patients and how to monitor for these malignancies.

The clinical performance of primary HPV screening, primary HPV screening plus cytology cotesting, and cytology alone at a tertiary care hospital

BACKGROUND

Algorithms for primary human papillomavirus (HPV) screening, primary HPV screening plus cytology cotesting, and cytology alone were evaluated previously in large cohort trials for cervical cancer detection, although the quality of cytology in those studies was controversial. To investigate whether these 3 algorithms would be applicable in routine practice at a tertiary care hospital, the authors compared their clinical performance. In addition, the prevalence of HPV genotypes was determined.

METHODS

Cervical cytology samples (n = 1000) were tested using liquid-based cytology (LBC), a nucleic acid hybridization assay, real-time polymerase chain reaction analysis, and direct HPV DNA sequencing. The clinical performance of the 3 algorithms was compared among women in different age groups (age range, 17-86 years; median age, 44.7 years).

RESULTS

For cervical intraepithelial neoplasia grade 2 or worse (CIN 2+), the sensitivity of primary HPV screening alone, cotesting, and LBC alone was 71.7%, 72.5%, and 63.8%, respectively; whereas the specificity was 87.5%, 96.5%, and 97.4%, respectively. Cotesting and LBC alone had slightly higher positive predictive values for CIN 2 + (97.8% and 98.9%, respectively) than primary HPV screening alone (91%), whereas primary HPV screening alone and cotesting demonstrated higher negative predictive values (63.6% and 62.5%, respectively) than LBC alone (43.2%). High-risk HPV types were detected in 24.3% of individuals. The most common type was HPV type 16 (HPV-16) followed by multiple HPV infections and HPV-58, HPV-52, HPV-31, HPV-35, HPV-51, HPV-39, HPV-56, HPV-33, HPV-18, HPV-59, and HPV-45.

CONCLUSIONS

Primary HPV screening alone in a tertiary care hospital demonstrated a performance that was equivalent to that of cotesting for CIN 2+, irrespective of patient age. With regard to the distribution of HPV genotypes, the nonavalent HPV vaccine would prevent approximately 60% of high-risk HPV.

Health and Economic Impact of Switching from a 4-Valent to a 9-Valent HPV Vaccination Program in the United States

BACKGROUND

Randomized clinical trials have shown the 9-valent human papillomavirus (HPV) vaccine to be highly effective against types 31/33/45/52/58 compared with the 4-valent. Evidence on the added health and economic benefit of the 9-valent is required for policy decisions. We compare population-level effectiveness and cost-effectiveness of 9- and 4-valent HPV vaccination in the United States.

METHODS

We used a multitype individual-based transmission-dynamic model of HPV infection and disease (anogenital warts and cervical, anogenital, and oropharyngeal cancers), 3% discount rate, and societal perspective. The model was calibrated to sexual behavior and epidemiologic data from the United States. In our base-case, we assumed 95% vaccine-type efficacy, lifelong protection, and a cost/dose of $145 and $158 for the 4- and 9-valent vaccine, respectively. Predictions are presented using the mean (80% uncertainty interval [UI] = 10(th)-90(th) percentiles) of simulations.

RESULTS

Under base-case assumptions, the 4-valent gender-neutral vaccination program is estimated to cost $5500 (80% UI = 2400-9400) and $7300 (80% UI = 4300-11 000)/quality-adjusted life-year (QALY) gained with and without cross-protection, respectively. Switching to a 9-valent gender-neutral program is estimated to be cost-saving irrespective of cross-protection assumptions. Finally, the incremental cost/QALY gained of switching to a 9-valent gender-neutral program (vs 9-valent girls/4-valent boys) is estimated to be $140 200 (80% UI = 4200->1 million) and $31 100 (80% UI = 2100->1 million) with and without cross-protection, respectively. Results are robust to assumptions about HPV natural history, screening methods, duration of protection, and healthcare costs.

CONCLUSIONS

Switching to a 9-valent gender-neutral HPV vaccination program is likely to be cost-saving if the additional cost/dose of the 9-valent is less than $13. Giving females the 9-valent vaccine provides the majority of benefits of a gender-neutral strategy.

Safety and immunogenicity of a 9-valent HPV vaccine in females 12-26 years of age who previously received the quadrivalent HPV vaccine

OBJECTIVES

To assess the safety and immunogenicity of the investigational 9-valent (6/11/16/18/31/33/45/52/58) HPV (9vHPV) vaccine in prior recipients of a 3-dose regimen of quadrivalent (6/11/16/18) HPV (qHPV) vaccine.

METHODS

V503-006 was a randomized, double-blinded, safety/tolerability and immunogenicity study of the 9vHPV vaccine in females 12-26 years of age who were previously vaccinated with qHPV vaccine. Subjects were randomized in a 2:1 ratio to receive 3 doses of 9vHPV vaccine (n=618) or saline placebo (n=306) at day 1, month 2, and month 6. Systemic, injection-site and serious adverse experiences (AEs) were monitored. Serum samples were collected at day 1, month 2, and month 7. Anti-HPV 6/11/16/18/31/33/45/52/58 titers were measured using the 9-valent HPV competitive Luminex Immunoassay (cLIA).

RESULTS

The frequency of injection-site AEs (days 1-5 following any vaccination) was higher in the 9vHPV vaccine group than in the placebo group (91.1% and 43.9%, respectively). The frequencies of vaccine-related systemic AEs (days 1-15 following any vaccination) were generally comparable between the 2 groups (30.6% in the 9vHPV vaccine group, and 25.9% in the placebo group). One vaccine-related serious AE was reported in each of the 9vHPV vaccine and placebo groups. Few subjects (9vHPV=0.5%; placebo=0%) discontinued due to an AE. At 4 weeks post-dose 3, over 98% of subjects in the 9vHPV vaccine group were seropositive for HPV types 31/33/45/52/58, with marked elevations in cLIA geometric mean titers (GMTs) to these HPV types. Anti-HPV 31/33/45/52/58 GMTs were lower than in subjects administered 9vHPV vaccine who had not previously received qHPV vaccine (based on cross-study analyses); the clinical significance of this difference is unknown.

CONCLUSIONS

Administration of a 3-dose regimen of 9vHPV vaccine to adolescent girls and young women 12-26 years of age who are prior qHPV vaccine recipients is highly immunogenic with respect to HPV types 31/33/45/52/58 and generally well tolerated.

9-Valent HPV vaccine for cancers, pre-cancers and genital warts related to HPV

Human papillomavirus (HPV) is the causative agent of nearly all cervical cancer cases as well as a substantial proportion of anal, vulvar, vaginal, penile and oropharyngeal cancers, making it responsible for approximately 5% of the global cancer burden. The first-generation HPV vaccines that is, quadrivalent HPV type 6/11/16/18 vaccine and bivalent HPV type 16/18 vaccine were licensed in 2006 and 2007, respectively. A second-generation 9-valent HPV type 6/11/16/18/31/33/45/52/58 vaccine with broader cancer coverage was initiated even before the first vaccines were approved. By preventing HPV infection and disease due to HPV31/33/45/52/58, the 9vHPV vaccine has the potential to increase prevention of cervical cancer from 70 to 90%. In addition, the 9vHPV vaccine has the potential to prevent 85-95% of HPV-related vulvar, vaginal and anal cancers. Overall, the 9vHPV vaccine addresses a significant unmet medical need, although further health economics and implementation research is needed.

Human papillomavirus genotypes among females in Mexico: a study from the Mexican institute for social security

BACKGROUND

The aetiological relationship between human papillomavirus (HPV) infection and cervical cancer (CC) is widely accepted. Our goal was to determine the prevalence of HPV types in Mexican women attending at the Mexican Institute for Social Security from different areas of Mexico.

MATERIALS AND METHODS

DNAs from 2,956 cervical samples were subjected to HPV genotyping: 1,020 samples with normal cytology, 931 with low-grade squamous intraepithelial lesions (LGSIL), 481 with high grade HGSIL and 524 CC.

RESULTS

Overall HPV prevalence was 67.1%. A total of 40 HPV types were found; HPV16 was detected in 39.4% of the HPV-positive samples followed by HPV18 at 7.5%, HPV31 at 7.1%, HPV59 at 4.9%, and HPV58 at 3.2%. HPV16 presented the highest prevalence both in women with altered or normal cytology and HPV 18 presented a minor prevalence as reported worldwide. The prevalence ratio (PR) was calculated for the HPV types. The analysis of PR showed that HPV16 presents the highest association with CC, HPV 31, -33, -45, -52 and -58 also demonstrating a high association.

CONCLUSIONS

The most prevalent HPV types in cervical cancer samples were -16, -18, -31, but it is important to note that we obtained a minor prevalence of HPV18 as reported worldwide, and that HPV58 and -52 also were genotypes with an important prevalence in CC samples. Determination of HPV genotypes is very important in order to evaluate the impact of vaccine introduction and future cervical cancer prevention strategies.

A Randomized, Double-Blind, Phase III Study of the Immunogenicity and Safety of a 9-Valent Human Papillomavirus L1 Virus-Like Particle Vaccine (V503) Versus Gardasil® in 9-15-Year-Old Girls

BACKGROUND

A 9-valent human papillomavirus (9vHPV) vaccine has been developed to prevent infections and diseases related to HPV 6/11/16/18 [as per the licensed quadrivalent HPV (qHPV) vaccine], as well as 5 additional oncogenic HPV types (HPV 31/33/45/52/58). Compared with the qHPV vaccine, the 9vHPV vaccine potentially increases the coverage of protection from 70% to 90% of cervical cancers. We compared the immunogenicity and safety of the 9vHPV vaccine versus the qHPV vaccine in 9-15-year-old girls.

METHODS

Participants (n = 600) were randomized to receive 9vHPV or qHPV vaccines on day 1, month 2 and month 6. Serology testing was performed on day 1 and month 7. HPV type-specific antibody titers (anti-HPV 6/11/16/18/31/33/45/52/58) were determined by competitive Luminex immunoassay and expressed as geometric mean titers and seroconversion rates. Vaccine safety was also assessed.

RESULTS

The HPV 6/11/16/18 immune responses elicited by the 9vHPV vaccine were comparable with those elicited by the qHPV vaccine. All participants (except 1 for HPV 45) receiving the 9vHPV vaccine seroconverted for HPV 31/33/45/52/58. The 9vHPV and qHPV vaccines showed comparable safety profiles, although the incidence of injection-site swelling was higher in the 9vHPV vaccine group.

CONCLUSIONS

In addition to immune responses to HPV 31/33/45/52/58, a 3-dose regimen of the 9vHPV vaccine elicited a similar immune response to HPV 6/11/16/18 when compared with the qHPV vaccine in girls aged 9-15 years. The safety profile was also similar for the 2 vaccines.

Coadministration of a 9-Valent Human Papillomavirus Vaccine With Meningococcal and Tdap Vaccines

BACKGROUND

This study in 11- to 15-year-old boys and girls compared the immunogenicity and safety of GARDASIL 9 (9-valent human papillomavirus [9vHPV] vaccine) administered either concomitantly or nonconcomitantly with 2 vaccines routinely administered in this age group (Menactra [MCV4; Neisseria meningitidis serotypes A/C/Y/W-135] or Adacel [Tdap; diphtheria/tetanus/acellular pertussis]).

METHODS

Participants received 9vHPV vaccine at day 1 and months 2 and 6; the concomitant group (n = 621) received MCV4/Tdap concomitantly with 9vHPV vaccine at day 1; the nonconcomitant group (n = 620) received MCV4/Tdap at month 1. Antibodies to HPV-, MCV4-, and Tdap-relevant antigens were determined. Injection-site and systemic adverse events (AEs) were monitored for 15 days after any vaccination; serious AEs were monitored throughout the study.

RESULTS

The geometric mean titers for all HPV types in 9vHPV vaccine 4 weeks after dose 3, proportion of subjects with a fourfold rise or greater in titers for 4 N meningitidis serotypes 4 weeks after injection with MCV4, proportion of subjects with antibody titers to diphtheria and tetanus ≥0.1 IU/mL, and geometric mean titers for pertussis antigens 4 weeks after injection with Tdap were all noninferior in the concomitant group compared with the nonconcomitant group. Injection-site swelling occurred more frequently in the concomitant group. There were no vaccine-related serious AEs.

CONCLUSIONS

Concomitant administration of 9vHPV vaccine with MCV4/Tdap was generally well tolerated and did not interfere with the antibody response to any of these vaccines. This strategy would minimize the number of visits required to deliver each vaccine individually.

Potential coverage of circulating HPV types by current and developing vaccines in a group of women in Bosnia and Herzegovina with abnormal Pap smears

The objectives of this study were to identify human papillomavirus (HPV) genotypes in a group of Bosnian-Herzegovinian women with abnormal cytology and to assess their potential coverage by vaccines. HPVs were identified by multiplex real-time PCR test (HPV High Risk Typing Real-TM; Sacace Biotechnologies, Italy) of 105 women with an abnormal cervical Pap smear and positive high-risk (HR) HPV DNA screening test. The most common genotypes in the study were HPV-16 (32·6%, 48/147), HPV-31 (14·3%, 21/147), HPV-51 (9·5%, 14/147) and HPV-18 (7·5%, 11/147). The overall frequency of HR HPV-16 and/or HPV-18, covered by currently available vaccines [Gardasil® (Merck & Co., USA) and Cervarix®; (GlaxoSmithKline, UK)] was lower than the overall frequency of other HPVs detected in the study (40·1%, 59/174, P = 0·017). Group prevalence of HR HPVs targeted by a nine-valent vaccine in development (code-named V503) was higher than total frequency of other HPVs detected (68·0%, 100/147, P < 0·001). Development of cervical cytological abnormalities was independent of the presence of multiple infections (χ 2 = 0·598, P = 0·741). Compared to other HPVs, dependence of cervical diagnosis and HPV-16, -18 (P = 0·008) and HPV-16, -18, -31 (P = 0·008) infections were observed. Vaccines targeting HR HPV-16, -18 and -31 might be an important tool in the prevention of cervical disease in Bosnia and Herzegovina.

Are the Two Human Papillomavirus Vaccines Really Similar? A Systematic Review of Available Evidence: Efficacy of the Two Vaccines against HPV

BACKGROUND

When the bivalent and the quadrivalent HPV vaccines were marketed they were presented as having comparable efficacy against cervical cancer. Differences between the vaccines are HPV types included and formulation of the adjuvant.

METHOD

A systematic review was conducted to assess the efficacy of the two vaccines against cervical cancer. Outcomes considered were CIN2+, CIN3+, and AIS.

RESULTS

Nine reports (38,419 women) were included. At enrollment mean age of women was 20 years, 90% had negative cytology, and 80% were seronegative and/or DNA negative for HPV 16 or 18 (naïve women). In the TVC-naïve, VE against CIN2+ was 58% (95% CI: 35, 72); heterogeneity was detected, VE being 65% (95% CI: 54, 74) for the bivalent and 43% (95% CI: 23, 57) for the quadrivalent. VE against CIN3+ was 78% (95% CI: <0, 97); heterogeneity was substantial, VE being 93% (95% CI: 77, 98) for the bivalent and 43% (95% CI: 12, 63) for the quadrivalent. VE in the TVC was much lower. No sufficient data were available on AIS.

CONCLUSIONS

In naïve girls bivalent vaccine shows higher efficacy, even if the number of events detected is low. In women already infected the benefit of the vaccination seems negligible.

Public health value of universal HPV vaccination

BACKGROUND

The story of Human Papillomavirus vaccination demands reflection not only for its public health impact on the prophylactic management of HPV disease, but also for its relevant economic and social outcomes. Greater than ever data confirm the efficacy and support the urge for effective vaccination plans for both genders before sexual debut.

METHODS

A review of previous experience in gender-restricted vaccination programs has demonstrated a lower effectiveness. Limiting vaccination to women might increase the psychological burden on women by confirming a perceived inequality between genders; and even if all women were immunized, the HPV chain of transmission would still be maintained through men.

RESULTS

The cost-effectiveness of including boys into HPV vaccination programs should be re-assessed in view of the progressive drop of the economic burden of HPV-related diseases in men and women due to universal vaccination. The cost of the remarkable increase in anal and oropharyngeal HPV driven cancers in both sexes has been grossly underestimated or ignored.

CONCLUSIONS

Steps must be taken by relevant bodies to achieve the target of universal vaccination. The analysis of HPV vaccination's clinical effectiveness vs. economic efficacy are supportive of the economic sustainability of vaccination programs both in women and men. In Europe, these achievements demand urgent attention to the social equity for both genders in healthcare. There is sufficient ethical, scientific, strategic and economic evidence to urge the European Community to develop and implement a coordinated and comprehensive strategy aimed at both genders and geographically balanced, to eradicate cervical cancer and other diseases caused by HPV in Europe. Policymakers must take into consideration effective vaccination programs in the prevention of cancers.

Development of a human papillomavirus competitive luminex immunoassay for 9 HPV types

In the clinical trials of the quadrivalent human papillomavirus (qHPV) vaccine, antibodies were measured by a competitive Luminex immunoassay (HPV-4 cLIA). A nine-valent HPV (9vHPV) vaccine targeting the types in the qHPV vaccine (HPV6/11/16/18), as well as 5 of the next most frequent HPV types found in cervical cancers worldwide (HPV31/33/45/52/58) is under development. To support the 9vHPV vaccine program, a nine-multiplexed cLIA (HPV-9 cLIA) was developed. Antibody titers were determined in a competitive format, where type-specific phycoerythrin (PE)-labeled, neutralizing mAbs (mAbs-PE) compete with an individual's serum antibodies for binding to conformationally sensitive, neutralizing epitopes on the VLPs. Neutralizing antibody levels were quantitated against a reference standard - a pool of sera from 6 Rhesus macaques that were immunized with the 9vHPV vaccine. Specificity of the mAbs was assessed by measuring their individual binding capacities to the type-specific and non-type-specific VLPs at alternative concentrations of the mAbs. Antibody assignments to the HPV-9 cLIA reference standard for HPV6/11/16/18 were determined to provide for a measure of consistency in serostatus assignment between the HPV-4 and HPV-9 cLIAs. Antibody assignments to the HPV-9 reference standard for HPV31/33/45/52/58 were obtained by calibration to HPV11 using a direct binding IgG assay. For each HPV VLP type, the cross-reactivity of the mAb-PEs in the HPV-9 cLIA was <1% (i.e., the mAb-PEs result in <1% non-specific binding). The antibody concentrations assigned to the HPV-9 cLIA reference standard for types 6/11/16/18/31/33/45/52/58 were 3,817, 2,889, 23,061, 5,271, 3,942, 2,672, 1,489, 1274, and 2263 mMU/mL, respectively.

E5 and E6/E7 of high-risk HPVs cooperate to enhance cancer progression through EMT initiation

It is estimated that 10-20% of human carcinogenesis is linked to virus infection including papillomaviruses (HPVs). Moreover, since metastatic cancer disease is a major cause of morbidity and mortality in cancer patients, the role of onco-viruses in cancer progression to a metastatic form is of particular interest. Recent studies reported that E5 and E6/E7 onco-proteins of high-risk HPVs could enhance cancer progression via the initiation of the epithelial-mesenchymal transition (EMT) event. Herein, we discuss the association between E5 as well as E6/E7 of high-risk HPV and cancer progression.

Human papillomaviruses-related cancers. Presence and prevention strategies in the Middle east and north African regions

Human papillomavirus (HPV) infections are estimated to be the most common sexually transmitted infections worldwide. Meanwhile, it is well established that infection by high-risk HPVs is considered the major cause of cervical cancer since more than 96% of these cancers are positive for high-risk HPVs, especially types 16 and 18. Moreover, during the last 2 decades, numerous studies pointed-out the possible involvement of high-risk HPV in several human carcinomas including head and neck, colorectal and breast cancers. The association between high-risk HPVs and cervical cancer and potentially other human malignancies would necessitate the introduction of vaccines which were generated against the 2 most frequent high-risk HPVs (types 16 and 18) worldwide, including the Middle East (ME) as well as North African countries. The presence of high-risk HPVs in the pathogenesis of human cancers in the ME, which is essential in order to evaluate the importance of vaccination against HPVs, has not been fully investigated yet. In this review, we present an overview of the existing epidemiological evidence regarding the presence of HPV in human cancers in the ME and the potential impact of vaccination against HPV infections and its outcome on human health in this region.

Immunogenicity and Safety of a 9-Valent HPV Vaccine

OBJECTIVES

Prophylactic vaccination of youngwomen aged 16 to 26 years with the 9-valent (6/11/16/18/31/33/45/52/58) human papillomavirus (HPV) virus-like particle (9vHPV) vaccine prevents infection and disease. We conducted a noninferiority immunogenicity study to bridge the findings in young women to girls and boys aged 9 to 15 years.

METHODS

Subjects (N = 3066) received a 3-dose regimen of 9vHPV vaccine administered at day 1, month 2, and month 6. Anti-HPV serologic assays were performed at day 1 and month 7. Noninferiority required that the lower bound of 2-sided 95% confidence intervals of geometric mean titer ratios (boys:young women or girls:young women) be >0.67 for each HPV type. Systemic and injection-site adverse experiences (AEs) and serious AEs were monitored.

RESULTS

At 4 weeks after dose 3, >99% of girls, boys, and young women seroconverted for each vaccine HPV type. Increases in geometric mean titers to HPV types 6/11/16/18/31/33/45/52/58 were elicited in all vaccine groups. Responses in girls and boys were noninferior to those of young women. Persistence of anti-HPV responses was demonstrated through 2.5 years after dose 3. Administration of the 9vHPV vaccine was generally well tolerated. A lower proportion of girls (81.9%) and boys (72.8%) than young women (85.4%) reported injection-site AEs, most of which were mild to moderate in intensity.

CONCLUSIONS

These data support bridging the efficacy findings with 9vHPV vaccine in young women 16 to 26 years of age to girls and boys 9 to 15 years of age and implementing gender-neutral HPV vaccination programs in preadolescents and adolescents.

Human papillomavirus genotype attribution for HPVs 6, 11, 16, 18, 31, 33, 45, 52 and 58 in female anogenital lesions

OBJECTIVE

Human papillomavirus (HPV) vaccines can potentially control cervical cancer and help to reduce other HPV-related cancers. We aimed to estimate the relative contribution (RC) of the nine types (HPVs 16/18/31/33/45/52/58/6/11) included in the recently approved 9-valent HPV vaccine in female anogenital cancers and precancerous lesions (cervix, vulva, vagina and anus).

METHODS

Estimations were based on an international study designed and coordinated at the Catalan Institute of Oncology (Barcelona-Spain), including information on 10,575 invasive cervical cancer (ICC), 1709 vulvar, 408 vaginal and 329 female anal cancer cases and 587 Vulvar Intraepitelial Neoplasia grade 2/3 (VIN2/3), 189 Vaginal Intraepitelial Neoplasia grade 2/3 (VaIN2/3) and 29 Anal Intraepitelial Neoplasia grade 2/3 (AIN2/3) lesions. Consecutive histologically confirmed paraffin-embedded cases were obtained from hospital pathology archives from 48 countries worldwide. HPV DNA-detection and typing was performed by SPF10-DEIA-LiPA25 system and RC was expressed as the proportion of type-specific cases among HPV positive samples. Multiple infections were added to single infections using a proportional weighting attribution.

RESULTS

HPV DNA prevalence was 84.9%, 28.6%, 74.3% and 90.0% for ICC, vulvar, vaginal and anal cancers, respectively, and 86.7%, 95.8% and 100% for VIN2/3, VaIN2/3 and AIN2/3, respectively. RC of the combined nine HPV types was 89.5% (95% confidence interval (CI): 88.8-90.1)-ICC, 87.1% (83.8-89.9)-vulvar, 85.5% (81.0-89.2)-vaginal, 95.9% (93.0-97.9)-female anal cancer, 94.1% (91.7-96.0)-VIN2/3, 78.7% (71.7-84.2)-VaIN2/3 and 86.2% (68.3-96.1)-AIN2/3. HPV16 was the most frequent type in all lesions. Variations in the RC of HPVs 31/33/45/52/58 by cancer site were observed, ranging from 7.8% (5.0-11.4)-female anal cancer to 20.5% (16.1-25.4)-vaginal cancer.

CONCLUSIONS

The addition of HPVs 31/33/45/52/58 to HPV types included in current vaccines (HPV16/18) could prevent almost 90% of HPV positive female anogenital lesions worldwide. Taking into account that most HPV-related cancers are ICC ones, the 9-valent HPV vaccine could potentially avoid almost 88% of all female anogenital cancers.

Vaccines against human papillomavirus in low and middle income countries: a review of safety, immunogenicity and efficacy

Currently, there is limited data on the immunogenicity and efficacy of human papillomavirus vaccines in Low and Middle income countries (LMIC). The review aims to summarize the current status from published HPV vaccine safety, immunogenicity and efficacy studies in low and middle income countries (LMIC). Electronic databases (PubMed/MEDLINE and HINARI) were searched for peer reviewed English language articles on HPV vaccination in LMIC that have so far been published from 1st January 2006 up to 30th January 2015. Eligible studies were included if they had used the bivalent (bHPV) or quadrivalent HPV (qHPV) vaccines in a LMIC and investigated safety, immunogenicity and/or efficacy. The main findings were extracted and summarized. A total of fourteen HPV vaccine studies assessing safety, Immunogenicity and efficacy of the bivalent or quadrivalent vaccines in LMIC were included. There are only ten published clinical trials where a LMIC has participated. There was no published study so far that assessed efficacy of the HPV vaccines in Sub-Saharan Africa. From these studies, vaccine induced immune response was comparable to that from results of HICs for all age groups. Studies assessing HPV vaccine efficacy of the bivalent or quadrivalent vaccine within LMIC were largely missing. Only three studies were found where a LMIC was part of a multi center clinical trial. In all the studies, there were no vaccine related serious adverse events. The findings from the only study that investigated less than three doses of the bivalent HPV-16/18 vaccine suggest that even with less than three doses, antibody levels were still comparable with older women where efficacy has been proven. The few studies from LMIC in this review had comparable safety, Immunogenicity and efficacy profiles like in HIC. Overall, the LMIC of Africa where immune compromising/modulating situations are prevalent, there is need for long term immunogenicity as well as surveillance studies for long term clinical effectiveness after two and three dose regimens.

An open-label, randomized study of a 9-valent human papillomavirus vaccine given concomitantly with diphtheria, tetanus, pertussis and poliomyelitis vaccines to healthy adolescents 11-15 years of age

BACKGROUND

A 9-valent human papillomavirus (9vHPV) vaccine has recently been reported to be safe and highly efficacious against infection and disease related to HPV6/11/16/18/31/33/45/52/58. We evaluated the immunogenicity and safety of the 9vHPV vaccine administered concomitantly with REPEVAX (diphtheria, tetanus, acellular pertussis and inactivated poliomyelitis vaccine).

METHODS

This open-label, randomized, multicenter study enrolled 1054 males and females ages 11-15 years. Subjects were randomly assigned to each group in a 1:1 ratio. Subjects received a 0.5 mL dose of 9vHPV vaccine intramuscularly at day 1, months 2 and 6 and a 0.5 mL dose of REPEVAX either on day 1 (concomitant vaccination group; n = 526) or at month 1 (nonconcomitant vaccination group, n = 528). Serologic responses for each vaccine component were tested by 1-sided tests of noninferiority between groups. Systemic and injection-site adverse experiences (AEs) and serious AEs were monitored.

RESULTS

Noninferiority of anti-HPV geometric mean titers and seroconversion rates for all 9vHPV antigens were demonstrated for the concomitant group compared with the nonconcomitant group. Seroconversion rates for the 9vHPV vaccine types were ≥99.8% in both groups at month 7. For REPEVAX, noninferiority of immune response was established for diphtheria, tetanus, all polio and pertussis antigens for both groups. There were no vaccine-related serious AEs.

CONCLUSION

Overall, concomitant administration of 9vHPV vaccine and REPEVAX was generally well tolerated and did not interfere with the immune response to either vaccine. This strategy would minimize the number of visits required to deliver each vaccine individually.

From the monovalent to the nine-valent HPV vaccine

An investigational monovalent human papillomavirus (HPV) 16 virus-like particle vaccine has been shown to prevent persistent infection and cervical disease related to HPV 16 and was proof of concept (2002). Designed to prevent the bulk of invasive cervical cancer, quadrivalent (HPV 6/11/16/18) and bivalent (HPV 16/18) vaccines have been available since 2006 and 2007, respectively. They are highly effective in preventing HPV 16/18-related cervical precancer; the quadrivalent version also prevents genital warts related to HPV 6/11. It has been shown that the precursors of vulvar, vaginal and anal cancer related to the vaccine types are effectively prevented. This led to a paradigm shift from a female-only cervical cancer vaccine to a vaccine for the prevention of HPV-related disease and cancer for both sexes. Vaccination before the start of sexual activity is most effective, and consequently most programs target 9- to 12-year-olds. Additionally, recent studies have proven the noninferior immunoresponse of a two-dose schedule in these age cohorts. Gender-neutral vaccination has become more common; it improves coverage and also provides protection to all males. Recently a nine-valent HPV vaccine (HPV 6/11/16/18/31/33/45/52/58) was licensed; it provides high and consistent protection against infections and diseases related to these types, with ∼90% of cervical and other HPV-related cancers and precancers potentially being avoided. Coverage is key. Efforts must be made to provide HPV vaccination in low-resource countries that lack screening programs. In countries with cervical cancer screening, HPV vaccination will greatly affect screening algorithms.

Potential impact of a nonavalent HPV vaccine on the occurrence of HPV-related diseases in France

BACKGROUND

Human Papillomavirus (HPV) infection is known to be associated with a number of conditions including cervical, vaginal, vulvar, penile, anal neoplasias and cancers, oropharynx cancers and genitals warts (GW). Two prophylactic vaccines are currently available: a bivalent vaccine designed to prevent HPV type 16 and 18 infection and a quadrivalent vaccine targeting HPV 6, 11, 16, and 18. In France, HPV vaccination is recommended in 11-14 year-old girls with a catch-up for girls aged 15-19. The objective of this study was to assess the potential impact of an HPV 6/11/16/18/31/33/45/52/58 nonavalent vaccine on anogenital and oropharyngeal HPV-related diseases in France.

METHODS

HPV genotype distributions from 6 multicentric retrospective studies (EDiTH I to VI) were analyzed including 516 cases of invasive cervical cancers (ICC), 493 high-grade cervical neoplasias (CIN2/3), 397 low-grade squamous intraepithelial lesions (LSIL), 423 GW, 366 anal cancer and 314 oropharyngeal carcinomas. Low and high estimates of HPV vaccine impact were calculated as follows: low estimate: prevalence of HPV 6/11/16/18/31/33/45/52/58 genotypes alone or in association but excluding presence of another HPV type; high estimate: prevalence of HPV 6/11/16/18/31/33/45/52/58 genotypes alone or in association, possibly in presence of another HPV type.

RESULTS

Estimates of potential impact varied from 85% (low estimate) to 92% (high estimate) for ICC, 77% to 90% for CIN2/3, 26% to 56% for LSIL, 69% to 90% for GW, 81% to 93% for anal cancer, and 41% to 44% for oropharyngeal carcinomas. Compared to the quadrivalent vaccine, the proportion of additional cases potentially prevented by the nonavalent vaccine was 9.9%-15.3% for ICC, 24.7%-33.3% for CIN2/3, 12.3%-22.7% for LSIL, 2.1%-5.4% for GW, 8.5%-10.4% for anal cancer, and 0.0%-1.6% for oropharyngeal carcinoma.

CONCLUSIONS

The nonavalent HPV vaccine showed significant increased potential impact compared to the HPV 6/11/16/18 quadrivalent vaccine for ICC, CIN2/3 and LSIL. Considering a 100% vaccine efficacy and high vaccine coverage, about 90% of ICC, CIN2/3, GW or anal cancer cases could be prevented by a nonavalent HPV vaccine in France.

Systematic review of model-based cervical screening evaluations

BACKGROUND

Optimising population-based cervical screening policies is becoming more complex due to the expanding range of screening technologies available and the interplay with vaccine-induced changes in epidemiology. Mathematical models are increasingly being applied to assess the impact of cervical cancer screening strategies.

METHODS

We systematically reviewed MEDLINE®, Embase, Web of Science®, EconLit, Health Economic Evaluation Database, and The Cochrane Library databases in order to identify the mathematical models of human papillomavirus (HPV) infection and cervical cancer progression used to assess the effectiveness and/or cost-effectiveness of cervical cancer screening strategies. Key model features and conclusions relevant to decision-making were extracted.

RESULTS

We found 153 articles meeting our eligibility criteria published up to May 2013. Most studies (72/153) evaluated the introduction of a new screening technology, with particular focus on the comparison of HPV DNA testing and cytology (n = 58). Twenty-eight in forty of these analyses supported HPV DNA primary screening implementation. A few studies analysed more recent technologies - rapid HPV DNA testing (n = 3), HPV DNA self-sampling (n = 4), and genotyping (n = 1) - and were also supportive of their introduction. However, no study was found on emerging molecular markers and their potential utility in future screening programmes. Most evaluations (113/153) were based on models simulating aggregate groups of women at risk of cervical cancer over time without accounting for HPV infection transmission. Calibration to country-specific outcome data is becoming more common, but has not yet become standard practice.

CONCLUSIONS

Models of cervical screening are increasingly used, and allow extrapolation of trial data to project the population-level health and economic impact of different screening policy. However, post-vaccination analyses have rarely incorporated transmission dynamics. Model calibration to country-specific data is increasingly common in recent studies.

Cervical cancer prevention: immunization and screening 2015

Both primary and secondary prevention of cervical cancer are now available. Immunizations against human papillomavirus (HPV) types 16 and 18 have the potential to prevent 70% of cancers of the cervix plus a large percentage of other lower anogenital tract cancers. Screening guidelines were recently changed to recommend cotesting with cytology plus an HPV test. The addition of HPV testing increases the sensitivity and negative predictive value of screening over the Papanicolaou (Pap) test alone.

US assessment of HPV types in cancers: implications for current and 9-valent HPV vaccines

BACKGROUND

This study sought to determine the prevaccine type-specific prevalence of human papillomavirus (HPV)-associated cancers in the United States to evaluate the potential impact of the HPV types in the current and newly approved 9-valent HPV vaccines.

METHODS

The Centers for Disease Control and Prevention partnered with seven US population-based cancer registries to obtain archival tissue for cancers diagnosed from 1993 to 2005. HPV testing was performed on 2670 case patients that were fairly representative of all participating cancer registry cases by age and sex. Demographic and clinical data were evaluated by anatomic site and HPV status. Current US cancer registry data and the detection of HPV types were used to estimate the number of cancers potentially preventable through vaccination.

RESULTS

HPV DNA was detected in 90.6% of cervical, 91.1% of anal, 75.0% of vaginal, 70.1% of oropharyngeal, 68.8% of vulvar, 63.3% of penile, 32.0% of oral cavity, and 20.9% of laryngeal cancers, as well as in 98.8% of cervical cancer in situ (CCIS). A vaccine targeting HPV 16/18 potentially prevents the majority of invasive cervical (66.2%), anal (79.4%), oropharyngeal (60.2%), and vaginal (55.1%) cancers, as well as many penile (47.9%), vulvar (48.6%) cancers: 24 858 cases annually. The 9-valent vaccine also targeting HPV 31/33/45/52/58 may prevent an additional 4.2% to 18.3% of cancers: 3944 cases annually. For most cancers, younger age at diagnosis was associated with higher HPV 16/18 prevalence. With the exception of oropharyngeal cancers and CCIS, HPV 16/18 prevalence was similar across racial/ethnic groups.

CONCLUSIONS

In the United States, current vaccines will reduce most HPV-associated cancers; a smaller additional reduction would be contributed by the new 9-valent vaccine.

Global availability of data on HPV genotype-distribution in cervical, vulvar and vaginal disease and genotype-specific prevalence and incidence of HPV infection in females

Background

Country-level HPV genotyping data may be sought by decision-makers to gauge the genotype-specific burden of HPV-related diseases in their jurisdiction and assess the potential impact of HPV vaccines. We investigated, by country, the availability of published literature on HPV genotypes in cervical, vaginal and vulvar cancers and intraepithelial neoplasms (CINs, VaINs and VINs) and on prevalence and incidence of genital HPV infections among women without clinically manifest disease.

Findings

Primary sources of publications were the PubMed/Medline and EMBASE databases. Original studies or meta-analyses published from 2000, covering genotypes 16 and 18 and at least one of genotypes 31/33/45/52/58, were included. Key exclusion criteria were language not English, cervical lesions not histologically confirmed (cytology only), special populations (e.g., immunocompromised) and, for cervical studies, small population (<50). A total of 727 studies reporting HPV genotype-specific data were identified: 366 for cervical cancers and CINs, 43 for vulvar or vaginal cancers and VINs/VaINs, and 395 and 21 for infection prevalence and incidence, respectively, in general female population samples. A large proportion of studies originated from a small set of countries. Cervical cancer/CIN typing data was scarce for several regions with the highest cervical cancer burden, including Eastern, Middle and Western Africa, Central America, South-East Asia, South Asia, and Eastern Europe. Data for vulvar/vaginal disease was limited outside of Europe and North America.

Conclusions

Although a large body of published HPV genotype-specific data is currently available, data gaps exist for genotype-specific infection incidence and several world regions with the highest cervical cancer burden.

Electronic supplementary material

The online version of this article (doi:10.1186/s13027-015-0008-y) contains supplementary material, which is available to authorized users.

Recent advances in the study of HPV-associated carcinogenesis

Human papillomaviruses (HPVs) cause virtually all cervical cancers, the second leading cause of death by cancer among women, as well as other anogenital cancers and a subset of head and neck cancers. Approximately half of women, who develop cervical cancer die from it. Despite the optimism that has accompanied the introduction of prophylactic vaccines to prevent some HPV infections, the relatively modest uptake of the vaccine, especially in the developing world, and the very high fraction of men and women who are already infected, means that HPV-associated disease will remain as a significant public health problem for decades. In this review, we summarize some recent findings on HPV-associated carcinogenesis, such as miRNAs in HPV-associated cancers, implication of stem cells in the biology and therapy of HPV-positive cancers, HPV vaccines, targeted therapy of cervical cancer, and drug treatment for HPV-induced intraepithelial neoplasias.

HPV vaccine: Current status and future directions

HPV Vaccine was introduced to prevent cervical cancer known to be caused by infection with one or more of the high risk subtypes of the Human papilloma virus (HPV). Since introduction, trials have proven its efficacy in preventing Cervical intraepithelial neoplasia (CIN) beyond doubt and its effectiveness in preventing cervical cancer though presumptive is reasonably certain as per mathematical modelling. It also prevents other HPV related anogenital and oropharyngeal malignancies in both sexes. HPV vaccines have courted many controversies related to its efficacy, safety, ideal age of vaccination, use in HPV infected individuals and use in males. The currently available vaccines are based on L1 Viral like particles (VLP) and hence highly species specific, thermolabile, costly and are purely prophylactic. The quest for a cheaper, thermostable and broad spectrum vaccine has led to many newer prophylactic vaccines. Therapeutic vaccines were born out of the inescapable necessity considering high HPV related morbidity projected in the non HPV naïve population. Therapeutic vaccines would immediately reduce this burden and also help in the management of HPV related cancers alone or as part of combination strategies. Ongoing research is aimed at a total control over HPV related malignancies in the near future.

Use of 9-valent human papillomavirus (HPV) vaccine: updated HPV vaccination recommendations of the advisory committee on immunization practices

During its February 2015 meeting, the Advisory Committee on Immunization Practices (ACIP) recommended 9-valent human papillomavirus (HPV) vaccine (9vHPV) (Gardasil 9, Merck and Co., Inc.) as one of three HPV vaccines that can be used for routine vaccination. HPV vaccine is recommended for routine vaccination at age 11 or 12 years. ACIP also recommends vaccination for females aged 13 through 26 years and males aged 13 through 21 years not vaccinated previously. Vaccination is also recommended through age 26 years for men who have sex with men and for immunocompromised persons (including those with HIV infection) if not vaccinated previously. 9vHPV is a noninfectious, virus-like particle (VLP) vaccine. Similar to quadrivalent HPV vaccine (4vHPV), 9vHPV contains HPV 6, 11, 16, and 18 VLPs. In addition, 9vHPV contains HPV 31, 33, 45, 52, and 58 VLPs. 9vHPV was approved by the Food and Drug Administration (FDA) on December 10, 2014, for use in females aged 9 through 26 years and males aged 9 through 15 years. For these recommendations, ACIP reviewed additional data on 9vHPV in males aged 16 through 26 years. 9vHPV and 4vHPV are licensed for use in females and males. Bivalent HPV vaccine (2vHPV), which contains HPV 16, 18 VLPs, is licensed for use in females. This report summarizes evidence considered by ACIP in recommending 9vHPV as one of three HPV vaccines that can be used for vaccination and provides recommendations for vaccine use.

Design of a large outcome trial for a multivalent human papillomavirus L1 virus-like particle vaccine

BACKGROUND

The 9-valent human papillomavirus (HPV) (9vHPV) vaccine targets the four HPV types (6/11/16/18) covered by the licensed quadrivalent HPV (qHPV) vaccine and five additional types (31/33/45/52/58). A large outcome trial of 9vHPV vaccine was conducted.

METHODS

An active control (qHPV vaccine) was used because a placebo is not ethically acceptable. Since qHPV vaccine is (and 9vHPV vaccine was anticipated to be) highly efficacious against HPV 6/11/16/18, low incidence of HPV 6/11/16/18-associated disease was expected. Consequently, an efficacy comparison of 9vHPV versus qHPV vaccine for HPV 6/11/16/18 would have been prohibitively large in size. Moreover, no minimum antibody level predicting protection against infection or disease is defined for HPV vaccination. As an alternative approach, the two vaccines were compared using immunogenicity bridging for HPV 6/11/16/18 and clinical efficacy for HPV 31/33/45/52/58.

RESULTS

The two co-primary objectives were to demonstrate: (1) non-inferior anti-HPV 6/11/16/18 antibody response; and (2) superior efficacy in HPV 31/33/45/52/58-related clinical outcome, for 9vHPV vaccine versus qHPV vaccine. For HPV 6/11/16/18, supportive analyses included a non-inferiority assessment of the percent risk reduction (compared to historical placebo) for 9vHPV versus qHPV vaccine.

CONCLUSIONS

A Phase III study of 9vHPV vaccine was successfully implemented. Experience from this study design may be applicable when developing a multivalent vaccine covering the same serotypes as an existing vaccine plus additional serotypes and there is no immune correlate of protection. Also, this study established that efficacy of a new HPV vaccine may be demonstrated using immunogenicity endpoints, which may open new options in HPV vaccine development.

A 9-valent HPV vaccine against infection and intraepithelial neoplasia in women

BACKGROUND

The investigational 9-valent viruslike particle vaccine against human papillomavirus (HPV) includes the HPV types in the quadrivalent HPV (qHPV) vaccine (6, 11, 16, and 18) and five additional oncogenic types (31, 33, 45, 52, and 58). Here we present the results of a study of the efficacy and immunogenicity of the 9vHPV vaccine in women 16 to 26 years of age.

METHODS

We performed a randomized, international, double-blind, phase 2b-3 study of the 9vHPV vaccine in 14,215 women. Participants received the 9vHPV vaccine or the qHPV vaccine in a series of three intramuscular injections on day 1 and at months 2 and 6. Serum was collected for analysis of antibody responses. Swabs of labial, vulvar, perineal, perianal, endocervical, and ectocervical tissue were obtained and used for HPV DNA testing, and liquid-based cytologic testing (Papanicolaou testing) was performed regularly. Tissue obtained by means of biopsy or as part of definitive therapy (including a loop electrosurgical excision procedure and conization) was tested for HPV.

RESULTS

The rate of high-grade cervical, vulvar, or vaginal disease irrespective of HPV type (i.e., disease caused by HPV types included in the 9vHPV vaccine and those not included) in the modified intention-to-treat population (which included participants with and those without prevalent infection or disease) was 14.0 per 1000 person-years in both vaccine groups. The rate of high-grade cervical, vulvar, or vaginal disease related to HPV-31, 33, 45, 52, and 58 in a prespecified per-protocol efficacy population (susceptible population) was 0.1 per 1000 person-years in the 9vHPV group and 1.6 per 1000 person-years in the qHPV group (efficacy of the 9vHPV vaccine, 96.7%; 95% confidence interval, 80.9 to 99.8). Antibody responses to HPV-6, 11, 16, and 18 were noninferior to those generated by the qHPV vaccine. Adverse events related to injection site were more common in the 9vHPV group than in the qHPV group.

CONCLUSIONS

The 9vHPV vaccine prevented infection and disease related to HPV-31, 33, 45, 52, and 58 in a susceptible population and generated an antibody response to HPV-6, 11, 16, and 18 that was noninferior to that generated by the qHPV vaccine. The 9vHPV vaccine did not prevent infection and disease related to HPV types beyond the nine types covered by the vaccine. (Funded by Merck; ClinicalTrials.gov number, NCT00543543).

Reduction in HPV 16/18-associated high grade cervical lesions following HPV vaccine introduction in the United States - 2008-2012

BACKGROUND

Prevention of pre-invasive cervical lesions is an important benefit of HPV vaccines, but demonstrating impact on these lesions is impeded by changes in cervical cancer screening. Monitoring vaccine-types associated with lesions can help distinguish vaccine impact from screening effects. We examined trends in prevalence of HPV 16/18 types detected in cervical intraepithelial neoplasia 2, 3, and adenocarcinoma in situ (CIN2+) among women diagnosed with CIN2+ from 2008 to 2012 by vaccination status. We estimated vaccine effectiveness against HPV 16/18-attributable CIN2+ among women who received ≥1 dose by increasing time intervals between date of first vaccination and the screening test that led to detection of CIN2+ lesion.

METHODS

Data are from a population-based sentinel surveillance system to monitor HPV vaccine impact on type-specific CIN2+ among adult female residents of five catchment areas in California, Connecticut, New York, Oregon, and Tennessee. Vaccination and cervical cancer screening information was retrieved. Archived diagnostic specimens were obtained from reporting laboratories for HPV DNA typing.

RESULTS

From 2008 to 2012, prevalence of HPV 16/18 in CIN2+ lesions statistically significantly decreased from 53.6% to 28.4% among women who received at least one dose (Ptrend<.001) but not among unvaccinated women (57.1% vs 52.5%; Ptrend=.08) or women with unknown vaccination status (55.0% vs 50.5%; Ptrend=.71). Estimated vaccine effectiveness for prevention of HPV 16/18-attributable CIN2+ was 21% (95% CI: 1-37), 49% (95% CI: 28-64), and 72% (95% CI: 45-86) in women who initiated vaccination 25-36 months, 37-48 months, and >48 months prior to the screening test that led to CIN2+ diagnosis.

CONCLUSIONS

Population-based data from the United States indicate significant reductions in CIN2+ lesions attributable to types targeted by the vaccines and increasing HPV vaccine effectiveness with increasing interval between first vaccination and earliest detection of cervical disease.

Impact of coverage-dependent marginal costs on optimal HPV vaccination strategies

The effectiveness of vaccinating males against the human papillomavirus (HPV) remains a controversial subject. Many existing studies conclude that increasing female coverage is more effective than diverting resources into male vaccination. Recently, several empirical studies on HPV immunization have been published, providing evidence of the fact that marginal vaccination costs increase with coverage. In this study, we use a stochastic agent-based modeling framework to revisit the male vaccination debate in light of these new findings. Within this framework, we assess the impact of coverage-dependent marginal costs of vaccine distribution on optimal immunization strategies against HPV. Focusing on the two scenarios of ongoing and new vaccination programs, we analyze different resource allocation policies and their effects on overall disease burden. Our results suggest that if the costs associated with vaccinating males are relatively close to those associated with vaccinating females, then coverage-dependent, increasing marginal costs may favor vaccination strategies that entail immunization of both genders. In particular, this study emphasizes the necessity for further empirical research on the nature of coverage-dependent vaccination costs.

Role of microRNAs in cancers of the female reproductive tract: insights from recent clinical and experimental discovery studies

microRNAs (miRNAs) are small RNA molecules that represent the top of the pyramid of many tumorigenesis cascade pathways as they have the ability to affect multiple, intricate, and still undiscovered downstream targets. Understanding how miRNA molecules serve as master regulators in these important networks involved in cancer initiation and progression open up significant innovative areas for therapy and diagnosis that have been sadly lacking for deadly female reproductive tract cancers. This review will highlight the recent advances in the field of miRNAs in epithelial ovarian cancer, endometrioid endometrial cancer and squamous-cell cervical carcinoma focusing on studies associated with actual clinical information in humans. Importantly, recent miRNA profiling studies have included well-characterized clinical specimens of female reproductive tract cancers, allowing for studies correlating miRNA expression with clinical outcomes. This review will summarize the current thoughts on the role of miRNA processing in unique miRNA species present in these cancers. In addition, this review will focus on current data regarding miRNA molecules as unique biomarkers associated with clinically significant outcomes such as overall survival and chemotherapy resistance. We will also discuss why specific miRNA molecules are not recapitulated across multiple studies of the same cancer type. Although the mechanistic contributions of miRNA molecules to these clinical phenomena have been confirmed using in vitro and pre-clinical mouse model systems, these studies are truly only the beginning of our understanding of the roles miRNAs play in cancers of the female reproductive tract. This review will also highlight useful areas for future research regarding miRNAs as therapeutic targets in cancers of the female reproductive tract.