Introduction and sustained high coverage of the HPV bivalent vaccine leads to a reduction in prevalence of HPV 16/18 and closely related HPV types

Assessing real world vaccine effectiveness: A review of Scotland's approach to monitoring human papillomavirus (HPV) vaccine impact on HPV infection and cervical disease

High-risk human papillomavirus (HPV) infections can progress to cervical cancer which is the fourth most common cancer in women globally. In Scotland, the incidence of cervical cancer has a strong socioeconomic deprivation gradient disproportionately affecting women from more deprived areas. An HPV vaccination programme was initiated in Scotland in 2008 targeting girls aged 12-13 years with a catch-up campaign running for the first three years for girls aged up to 18 years. The programme has evolved over the last 16 years with changes in the type of vaccine, dosing schedules and the extension of the programme to boys and gay, bisexual and other men who have sex with men. Vaccine uptake in Scotland has historically been high but has gradually decreased over time and disparities exist in women from more deprived areas of Scotland. The ability to link national immunisation and screening databases in Scotland has allowed direct monitoring of the impact of the HPV vaccine on virological and histological outcomes. Analyses of this linked data have demonstrated real-world evidence of high vaccine effectiveness against HPV infection, cervical disease, and cervical cancer with evidence of herd immunity in unvaccinated women. Continued monitoring is crucial to assess the duration of protection, the impact of vaccine and dosing schedules changes and the emergence of potential type replacement. With the World Health Organisation's aim to eliminate cervical cancer as a public health problem by the next century addressing the inequalities in cervical cancer incidence will be crucial. This will require targeted interventions for women most at risk of cervical cancer to ensure elimination is achieved timely for all women in Scotland.

Vaccination and screening strategies to accelerate cervical cancer elimination in Norway: a model-based analysis

BACKGROUND

Experts have proposed an 'EVEN FASTER' concept targeting age-groups maintaining circulation of human papillomavirus (HPV). We explored effects of the vaccination component of these proposals compared with cervical cancer (CC) screening-based interventions on age-standardized incidence rate (ASR) and CC elimination (<4 cases/100,000) timing in Norway.

METHODS

We used a model-based approach to evaluate HPV vaccination and CC screening scenarios compared with a status-quo scenario reflecting previous vaccination and screening. For cohorts ages 25-30 years, we examined 6 vaccination scenarios that incrementally increased vaccination coverage from current cohort-specific rates. Each vaccination scenario was coupled with three screening strategies that varied screening frequency. Additionally, we included 4 scenarios that alternatively increased screening adherence. Population- and cohort-level outcomes included ASR, lifetime risk of CC, and colposcopy referrals.

RESULTS

Several vaccination strategies coupled with de-intensified screening frequencies lowered ASR, but did not accelerate CC elimination. Alternative strategies that increased screening adherence could both accelerate elimination and improve ASR.

CONCLUSIONS

The vaccination component of an 'EVEN FASTER' campaign is unlikely to accelerate CC elimination in Norway but may reduce population-level ASR. Alternatively, targeting under- and never-screeners may both eliminate CC faster and lead to greater health benefits compared with vaccination-based interventions we considered.

Cost-effectiveness of primary human papillomavirus triage approaches among vaccinated women in Norway: A model-based analysis

As Norway considers revising triage approaches following their first adolescent cohort with human papillomavirus (HPV) vaccination entering the cervical cancer screening program, we analyzed the health impact and cost-effectiveness of alternative primary HPV triage approaches for women initiating cervical cancer screening in 2023. We used a multimodeling approach that captured HPV transmission and cervical carcinogenesis to evaluate the health benefits, harms and cost-effectiveness of alternative extended genotyping and age-based triage strategies under five-yearly primary HPV testing (including the status-quo screening strategy in Norway) for women born in 1998 (ie, age 25 in 2023). We examined 35 strategies that varied alternative groupings of high-risk HPV genotypes ("high-risk" genotypes; "medium-risk" genotypes or "intermediate-risk" genotypes), number and types of HPV included in each group, management of HPV-positive women to direct colposcopy or active surveillance, wait time for re-testing and age at which the HPV triage algorithm switched from less to more intensive strategies. Given the range of benchmarks for severity-specific cost-effectiveness thresholds in Norway, we found that the preferred strategy for vaccinated women aged 25 years in 2023 involved an age-based switch from a less to more intensive follow-up algorithm at age 30 or 35 years with HPV-16/18 genotypes in the "high-risk" group. The two potentially cost-effective strategies could reduce the number of colposcopies compared to current guidelines and simultaneously improve health benefits. Using age to guide primary HPV triage, paired with selective HPV genotype and follow-up time for re-testing, could improve both the cervical cancer program effectiveness and efficiency.

Performance of the HPV E6/E7 mRNA Aptima HPV assay combined with partial genotyping compared with the HPV DNA Cobas 4800 HPV test for use in primary screening: Results from the CERVIVA HPV primary screening study in Ireland

There are currently several validated HPV tests. However, longitudinal data which spans appropriate age ranges, as well as evaluation of potential screening algorithms are necessary for screening programmes choice of test. The objective of our study was to evaluate the performance of HPV mRNA and HPV DNA testing, including partial genotyping, in routine cervical screening. As part of the CERVIVA HPV Primary Screening Study, ThinPrep samples from 10 150 women were tested for HPV mRNA using the Aptima HPV assay and HPV DNA using the Cobas 4800 HPV test. HPV mRNA-positive women were further assessed with the Aptima genotyping assay for HPV 16/18/45. Baseline cytology and prospective follow-up data were collected. The performance of the two tests was examined over 42 months (to date). HPV mRNA demonstrated equivalent sensitivity to HPV DNA testing for detection of CIN2+ (93.2% [92.4-93.9] vs 92.8% [92.0-93.6], respectively) and CIN3+ (94.6% [93.8-95.3] vs 94.6% [93.8-95.3]). HPV mRNA testing had significantly higher specificity compared to HPV DNA for detection of CIN2+ (84.0% [83.5-84.5] vs 80.8% [80.2-81.4], respectively) and CIN3+ (88.44% [88.2-88.6] vs 85.62 [85.4-85.9]). The proportion of CIN2+ and CIN3+, over 3 years (42 months), in HPV-negative women was comparable for both RNA (0.20% and 0.10%) and DNA (0.22% and 0.11%). Genotyping data was comparable across both assay platforms. In the context of HPV primary screening HPV mRNA testing has potential to reduce triage tests and follow-up tests at 12 months compared to DNA testing, with no significant difference in detection of CIN2+ and CIN3+.

Can prophylactic HPV vaccination reduce the recurrence of cervical lesions after surgery? Review and prospect

Women with HSIL typically undergo conization/LEEP to remove cervical lesions, but the risk of HSIL lesions returning after surgical treatment remains higher than in the general population. HPV vaccination is essential to prevent cervical cancer. However, the effect of prophylactic HPV vaccination on reducing the risk of recurrent cervical lesions after surgical treatment remains unclear. This review aims to analyze and summarize the latest literature on the role of prophylactic HPV vaccine in reducing the recurrence of cervical lesions after surgery in patients with HSIL, and to review and update the history, efficacy, effectiveness and safety of HPV vaccine, focusing on the current status of global HPV vaccine implementation and obstacles.

Human papillomavirus vaccine effectiveness by age at vaccination: A systematic review

Human papillomavirus (HPV) vaccines work by preventing infections prior to natural exposure. Thus, it is likely more effective at younger ages, and it is important to understand how effectiveness might be diminished when administered at older ages. We conducted a systematic review of HPV vaccine effectiveness studies published between 2007 and 2022 that included an analysis of effectiveness against vaccine-type HPV infections, anogenital warts, cervical abnormalities and cervical cancer by age at vaccine initiation or completion. Searching multiple databases, 21 studies were included and results were summarized descriptively. Seventeen studies found the highest vaccine effectiveness in the youngest age group. Vaccine effectiveness estimates for younger adolescents ages 9-14 years ranged from approximately 74% to 93% and from 12% to 90% for adolescents ages 15-18 years. These results demonstrate that the HPV vaccine is most effective against HPV-related disease outcomes when given at younger ages, emphasizing the importance of on-time vaccination.

A single dose of quadrivalent HPV vaccine is highly effective against HPV genotypes 16 and 18 detection in young pregnant women eight years following vaccination: an retrospective cohort study in Fiji

Background

In 2008/9, Fiji vaccinated >30,000 girls aged 9-12 years with the quadrivalent human papillomavirus (4vHPV) vaccine coverage for at least one dose was >60% (one dose only was 14%, two dose only was 13%, three doses was 35%). We calculated vaccine effectiveness (VE) of one, two and three doses of 4vHPV against oncogenic HPV genotypes 16/18, eight years following vaccination.

Methods

A retrospective cohort study was undertaken (2015-2019) in pregnant women ≤23 years old, eligible to receive 4vHPV in 2008/9, with confirmed vaccination status. The study was restricted to pregnant women due to the cultural sensitivity of asking about sexual behavior in Fiji. For each participant a clinician collected a questionnaire, vaginal swab and genital warts examination, a median eight (range 6-11) years post vaccination. HPV DNA was detected by molecular methods. Adjusted VE (aVE) against the detection of vaccine HPV genotypes (16/18), the comparison group of non-vaccine genotypes (31/33/35/39/45/51/52/56/58/59/66/68), and genital warts were calculated. Covariates included in the adjusted model were: age, ethnicity and smoking, according to univariate association with any HPV detection.

Findings

Among 822 participants the prevalence of HPV 16/18 in the unvaccinated, one, two and three-dose groups were 13.3% (50/376), 2.5% (4/158), 0% (0/99) and 1.6% (3/189), respectively; and for the non-vaccine high-risk genotypes, the detection rate was similar across dosage groups (33.2%-40.4%, p = 0.321). The aVE against HPV 16/18 for one, two and three doses were 81% (95% CI; 48-93%), 100% (95% CI; 100-100%), and 89% (95% CI; 64-96%), respectively. Prevalence of HPV 16/18 was lower among women with longer time since vaccination.

Interpretations

A single dose 4vHPV vaccine is highly effective against HPV genotypes 16 and 18 eight years following vaccination. Our results provide the longest duration of protection for reduced dose 4vHPV schedule in a low- or middle-income country in the Western Pacific region.

Funding

This study was supported by the Bill & Melinda Gates Foundation and the Department of Foreign Affairs and Trade of the Australian Government and Fiji Health Sector Support Program (FHSSP). FHSSP is implemented by Abt JTA on behalf of the Australian Government.

Effectiveness of quadrivalent HPV vaccination in reducing vaccine-type and nonvaccine-type high risk HPV infection

This study aimed to assess human papillomavirus (HPV) vaccine effectiveness (VE) against both vaccine-type and nonvaccine-type high-risk HPV (hrHPV) infection, and duration of protection in United States. The study population was female participants aged 18-35 years with an HPV vaccination history and genital testing for HPV from the National Health and Nutrition Examination Survey, 2007-2016. Participants vaccinated before sexual debut were assessed against 13 nonvaccine-type hrHPV infection including 31/33/35/39/45/51/52/56/58/59/68/73/82. Multivariable logistic regression was used to estimate VE overall, by age at diagnosis, time since vaccination and lifetime sexual partners. A total of 3866 women were included in the analysis, with 23.3% (95% CI 21.3%-25.4%) having been vaccinated (≥1 dose). VE against vaccine-type HPV18/16/11/6 infection was 58% overall, which was mainly driven by those aged 18-22 years (VE = 64%) and 23-27 years (65%). Among participants aged 18-22 years vaccinated before sexual debut, the VE was 47% (23%-64%) against 13 nonvaccine-type hrHPV and 61% (95% CI 36%-77%) against 5 selected nonvaccine-type hrHPV35/39/52/58/59. Both direct effectiveness and cross-protection maintained effective for 5-10 years post vaccination. We also found the prevalence of ever diagnosed cervical cancer among vaccinated was significantly lower (0.46%, 4/874) than that among unvaccinated participants (1.27%, 38/2992). These findings highlight the potential of significant reduction of cervical cancer following the universal HPV vaccination programme.

Ability of epidemiological studies to monitor HPV post-vaccination dynamics: a simulation study

Genital human papillomavirus (HPV) infections are caused by a broad diversity of genotypes. As available vaccines target a subgroup of these genotypes, monitoring transmission dynamics of nonvaccine genotypes is essential. After reviewing the epidemiological literature on study designs aiming to monitor those dynamics, we evaluated their abilities to detect HPV-prevalence changes following vaccine introduction. We developed an agent-based model to simulate HPV transmission in a heterosexual population under various scenarios of vaccine coverage and genotypic interaction, and reproduced two study designs: post-vs.-prevaccine and vaccinated-vs.-unvaccinated comparisons. We calculated the total sample size required to detect statistically significant prevalence differences at the 5% significance level and 80% power. Although a decrease in vaccine-genotype prevalence was detectable as early as 1 year after vaccine introduction, simulations indicated that the indirect impact on nonvaccine-genotype prevalence (a decrease under synergistic interaction or an increase under competitive interaction) would only be measurable after >10 years whatever the vaccine coverage. Sample sizes required for nonvaccine genotypes were >5 times greater than for vaccine genotypes and tended to be smaller in the post-vs.-prevaccine than in the vaccinated-vs.-unvaccinated design. These results highlight that previously published epidemiological studies were not powerful enough to efficiently detect changes in nonvaccine-genotype prevalence.

Molecular diagnostics of infectious disease: Detection and characterization of microbial agents in cytology samples

BACKGROUND

Cytology samples are widely used to diagnose various infectious diseases by detection and identification of causative infectious agents, including bacteria, fungi, and viruses. The role of cytopathology in infectious disease has expanded tremendously in the past decades with the advances in molecular techniques. Molecular diagnostic methods, compared to conventional methods, have shown improved patient outcome, reduction in cost, and shortened hospital stay times. The aim of this article is to review molecular testing in cytology samples for diagnosis of infectious diseases.

METHODS

The literature search for molecular testing in common cytology samples for diagnosis of infectious diseases was performed. The findings of the studies were summarized. The common cytology samples included in this article were gynecologic specimens, cerebrospinal fluid, bronchoalveolar lavage, and urine samples.

CONCLUSIONS

There are a number of molecular diagnostic tests that are available to be used in common cytology samples to detect infectious agents. Each test has its own advantages and limitations. It is our hope that upon reading this review article, the readers will have better understanding of molecular diagnostic testing of infectious diseases utilizing commonly sampled cytology specimens in daily practice.

Public health impact and cost-effectiveness of switching from bivalent to nonavalent vaccine for human papillomavirus in Norway: incorporating the full health impact of all HPV-related diseases

AIM

The objective of this study was to estimate and compare the cost-effectiveness of switching from a bivalent to a nonavalent human papillomavirus (HPV) vaccination program in Norway, incorporating all nonavalent vaccine-preventable HPV-related diseases and in the context of the latest cervical cancer screening program.

METHODS

A well-established dynamic transmission model of the natural history of HPV infection and disease was adapted to the Norwegian population. We determined the number of cases of HPV-related diseases and subsequent number of deaths, and the economic burden of HPV-related disease under the current standard of care conditions of bivalent and nonavalent vaccinations of girls and boys aged 12 years.

RESULTS

Compared to bivalent vaccination, nonavalent vaccination averted an additional 4,357 cases of HPV-related cancers, 421,925 cases of genital warts, and 543 cases of recurrent respiratory papillomatosis (RRP) over a 100-year time horizon. Nonavalent vaccination also averted an additional 1,044 deaths over the 100-year time horizon when compared with bivalent vaccination. Total costs were higher for the nonavalent strategy (10.5 billion NOK [€1.03 billion] vs. 9.3-9.4 billion NOK [€915-925 million] for bivalent vaccination). A switch to nonavalent vaccination had a higher vaccination cost (4.4 billion NOK [€433 million] vs. 2.7 billion NOK [€266 million] for bivalent vaccination) but resulted in a savings of 627-694 million NOK [€62-68 million] in treatment costs. A switch to nonavalent vaccination demonstrated an incremental cost-effectiveness ratio of 102,500 NOK (€10,086) per QALY versus bivalent vaccination.

CONCLUSIONS

Using a model that incorporated the full range of HPV-related diseases, and the latest cervical cancer screening practices, we found that switching from bivalent to nonavalent vaccination would be considered cost-effective in Norway.

Human papillomavirus vaccine effectiveness by number of doses: Updated systematic review of data from national immunization programs

BACKGROUND

Human papillomavirus (HPV) vaccines were first licensed as a three-dose series. Two doses are now widely recommended in some age groups; there are data suggesting high efficacy with one dose. We updated a systematic literature review of HPV vaccine effectiveness by number of doses in observational studies.

METHODS

We searched Medline and Embase databases from January 1, 2007, through September 29, 2021. Data were extracted and summarized in a narrative synthesis. We also conducted quality assessments for bias due to selection, information, and confounding.

RESULTS

Overall, 35 studies were included; all except one were conducted within the context of a recommended three-dose schedule. Evaluations were in countries that used bivalent HPV vaccine (seven), quadrivalent HPV vaccine (27) or both (one). Nine evaluated effectiveness against HPV infection, ten anogenital warts, and 16 cervical abnormalities. All studies were judged to have moderate or serious risk of bias. The biases rated as serious would likely result in lower effectiveness with fewer doses. Investigators attempted to control for or stratify by potentially important variables, such as age at vaccination. Eight studies evaluated impact of buffer periods (lag time) for case counting and 10 evaluated different intervals between doses for two-dose vaccine recipients. Studies that stratified by vaccination age found higher effectiveness with younger age at vaccination, although differences were not all formally tested. Most studies found highest estimates of effectiveness with three doses; significant effectiveness was found among 28/29 studies that evaluated three doses, 19/29 that evaluated two doses, and 18/30 that evaluated one dose. Some studies that adjusted or stratified analyses by age at vaccination found similar effectiveness with three, two and one doses.

CONCLUSION

Observational studies of HPV vaccine effectiveness have many biases. Studies examining persons vaccinated prior to sexual activity and using methods to reduce sources of bias are needed for valid effectiveness estimates.

HPV Vaccination in Women with Cervical Intraepithelial Neoplasia Undergoing Excisional Treatment: Insights into Unsolved Questions

Several questions regarding the role of vaccination in women treated for high-grade cervical intraepithelial lesion (HSIL) have not been clarified. One of the main queries is whether the time at which the vaccine is administered (before or after treatment) influences the protection against post-treatment HSIL. A second unanswered question is whether the vaccine has any effect in women with persistent HPV after treatment. We aimed to address these questions in a study of 398 women undergoing excisional treatment from July 2016 to December 2019. Vaccination was funded and offered to all women undergoing treatment. A total of 306 women (76.9%) accepted HPV vaccination (vaccinated group): 113 (36.9%) received the first dose before excision and 193 (63.1%) after the procedure. A total of 92 women (23.1%) refused the vaccine (non-vaccinated group). Women vaccinated before treatment showed a lower rate of post-treatment HSIL compared with non-vaccinated women (0.9% vs. 6.5%; p = 0.047). Among women with persistent HPV infection after treatment, those who had received the vaccine showed a lower prevalence of post-treatment HSIL than non-vaccinated women (2.6% vs. 10.5%; p = 0.043). In conclusion, this study shows that HPV vaccination before treatment reduces the prevalence of post-treatment HSIL and suggests that vaccination might even benefit women with persistent HPV after treatment.

Cervical Intraepithelial Neoplasia 3 (Cervical Intraepithelial Neoplasia 3/High-Grade Squamous Intraepithelial Lesion) in Human Papillomavirus-Vaccinated Women-Results From a Tertiary Referral Center

OBJECTIVE

High-grade cervical intraepithelial neoplasia (CIN 3) still develops in some vaccinated women despite established effectiveness of prophylactic human papillomavirus (HPV) vaccination. The purpose of this study was to define characteristics of women with CIN 3 after HPV vaccination referred to a gynecological dysplasia unit.

MATERIALS AND METHODS

Retrospective analysis of HPV-vaccinated women with CIN 3 in a single German center. Between July 2018 and September 2020, 791 women were referred to our university hospital-based dysplasia unit for colposcopic evaluation of abnormal cytological findings. Human papillomavirus vaccination status was retrieved. Human papillomavirus typing was performed in lesional biopsies and cervical swabs.

RESULTS

Nine women were identified who had previously been vaccinated with the quadrivalent HPV vaccine (Q-HPV) and were diagnosed with histologically confirmed CIN 3/high-grade squamous intraepithelial lesion. The Q-HPV had been administered between 12 and 28 years of age and 1-13 years before CIN 3 diagnosis. Nine different high-risk (HR)-HPV types were found in the CIN 3 biopsies, 6 monoinfections (twice HPV 16, once HPV 18, HPV 31, HPV 52, HPV 58, respectively) and 3 dual infections (HPV 33 + 52, HPV 51 + 52, HPV 53 + 66). Seven of these 9 HR-HPV types are not covered by Q-HPV, but only 2 CIN 3 lesions carried HR-HPV types not included in the nonavalent HPV vaccine.

CONCLUSIONS

It is important to implement vaccination recommendations and administer HPV vaccination as early as possible in HPV-naive individuals. Because not all HR-HPV types are covered by the available HPV vaccines, other types may still cause CIN 3/high-grade squamous intraepithelial lesion. This requires further screening after vaccination, especially in women who were previously vaccinated with the bivalent or the quadrivalent HPV vaccine.

Identifying a Single Optimal Integrated Cervical Cancer Prevention Policy in Norway: A Cost-Effectiveness Analysis

BACKGROUND

Interventions targeting the same disease but at different points along the disease continuum (e.g., screening and vaccination to prevent cervical cancer [CC]) are often evaluated in isolation, which can affect cost-effectiveness profiles and policy conclusions. We evaluated nonavalent human papillomavirus (HPV) vaccine (9vHPV) compared with bivalent HPV vaccine (2vHPV) alongside deintensified screening intervals for a vaccinated birth cohort to inform a single optimal integrated CC prevention policy.

METHODS

Using a multimodeling approach, we evaluated the health and economic impacts of alternative CC screening strategies for a Norwegian birth cohort eligible for HPV vaccination in 2021 assuming they received 1) 2vHPV or 2) 9vHPV. We conducted 1) a restricted analysis that evaluated the optimal HPV vaccine under current screening guidelines; and 2) a comprehensive analysis including alternative screening and vaccination strategy combinations. We calculated incremental cost-effectiveness ratios (ICERs) and evaluated them according to different cost-effectiveness thresholds.

RESULTS

Assuming a cost-effectiveness threshold of $40,000 per quality-adjusted life year (QALY) gained, we found that, while holding screening intensity fixed, switching the routine vaccination program in Norway from 2vHPV to 9vHPV would not be considered cost-effective (ICER of $132,700 per QALY gained). However, when allowing for varying intensities of CC screening, we found that switching to 9vHPV would be cost-effective compared with 2vHPV under an alternative threshold of $55,000 per QALY gained, if coupled with reductions in the number of lifetime screens.

CONCLUSIONS

Our analysis highlights the importance of evaluating the full potential policy landscape for country-level decision makers considering policy adoption, including nonindependent primary and secondary prevention efforts, to draw appropriate conclusions and avoid sub-optimal outcomes.

HIGHLIGHTS

Without evaluating the full potential policy landscape, including primary and secondary prevention efforts, country-level decision makers may not be able to draw appropriate policy conclusions, resulting in suboptimal outcomes.An applied example from cervical cancer prevention in Norway compared a restricted analysis of current screening guidelines to a comprehensive analysis including alternative screening and vaccination strategy combinations.We found that a switch from bivalent to nonavalent human papillomavirus vaccine would be considered cost-effective in Norway if coupled with reductions in the number of lifetime screens compared with the current screening strategy.A comprehensive analysis that considers how different types of interventions along the disease continuum affect each other will be critical for decision makers interpreting cost-effectiveness analysis results.

Switching clinic-based cervical cancer screening programs to human papillomavirus self-sampling: A cost-effectiveness analysis of vaccinated and unvaccinated Norwegian women

Several countries have implemented primary human papillomavirus (HPV) testing for cervical cancer screening. HPV testing enables home-based, self-collected sampling (self-sampling), which provides similar diagnostic accuracy as clinician-collected samples. We evaluated the impact and cost-effectiveness of switching an entire organized screening program to primary HPV self-sampling among cohorts of HPV vaccinated and unvaccinated Norwegian women. We conducted a model-based analysis to project long-term health and economic outcomes for birth cohorts with different HPV vaccine exposure, that is, preadolescent vaccination (2000- and 2008-cohorts), multiage cohort vaccination (1991-cohort) or no vaccination (1985-cohort). We compared the cost-effectiveness of switching current guidelines with clinician-collected HPV testing to HPV self-sampling for these cohorts and considered an additional 44 strategies involving either HPV self-sampling or clinician-collected HPV testing at different screening frequencies for the 2000- and 2008-cohorts. Given Norwegian benchmarks for cost-effectiveness, we considered a strategy with an additional cost per quality-adjusted life-year below $55 000 as cost-effective. HPV self-sampling strategies considerably reduced screening costs (ie, by 24%-40% across cohorts and alternative strategies) and were more cost-effective than clinician-collected HPV testing. For cohorts offered preadolescent vaccination, cost-effective strategies involved HPV self-sampling three times (2000-cohort) and twice (2008-cohort) per lifetime. In conclusion, we found that switching from clinician-collected to self-collected HPV testing in cervical screening may be cost-effective among both highly vaccinated and unvaccinated cohorts of Norwegian women.

Impact of Delaying Effective and Cost-Effective Policy Decisions: An Example From Cervical Cancer Prevention in Norway

Introduction. Delayed implementation of evidence-driven interventions has consequences that can be formally evaluated. In Norway, programs to prevent cervical cancer (CC)—screening and treatment of precancerous lesions and prophylactic vaccination against human papillomavirus (HPV) infection—have been implemented, but each encountered delays in policy implementation. To examine the effect of these delays, we project the outcomes that would have been achieved with timely implementation of two policy changes compared with the de facto delays in implementation (in Norway). Methods. We used a multimodeling approach that combined HPV transmission and cervical carcinogenesis to estimate the health outcomes and timeline for CC elimination associated with the implementation of two CC prevention policy decisions: a multicohort vaccination program of women up to age 26 years with bivalent vaccine in 2009 compared with actual “delayed” implementation in 2016, and a switch from cytology to primary HPV-based testing in 2015 compared with “delayed” rollout in 2020. Results. Timely implementation of two policy changes compared with current Norwegian prevention policy timeline could have averted approximately 970 additional cases (range of top 10 sets: 830–1060) and accelerated the CC elimination timeline by around 4 years (from 2039 to 2035). Conclusions. If delaying implementation of effective and cost-effective interventions is being considered, the decision-making process should include quantitative analyses on the effects of delays.

Reduction in Vaccine HPV Type Infections in a Young Women Group (18-25 Years) Five Years after HPV Vaccine Introduction in Colombia

In Colombia, the human papillomavirus (HPV) vaccine was launched in 2012 in the context of a school-based national vaccination program targeting girls ages 9 to 14 and offering catch-up vaccination for girls ages 14 to 17. In this study, we evaluated the program's impact on type-specific HPV infection by comparing HPV cervical prevalence among vaccinated and nonvaccinated women. This is a comparative cross-sectional study conducted 5 years after the quadrivalent HPV vaccination implementation in a sentinel Colombian City. This study included young women (18-25 years old) who had been vaccinated in the catch-up group and were attending universities and technical institutions, and women who attended primary health care facilities for Pap smear screening. The HPV prevalence of 1,287 unvaccinated women was compared with the prevalence of 1,986 vaccinated women. The prevalence of HPV16/18 infections was significantly lower in vaccinated compared with unvaccinated women (6.5% vs. 15.4%; P < 0.001), whereas for HPV6/11 infections, a decrease of 63.7% in vaccinated women (1.02% vs. 2.81%) was observed. The adjusted effectiveness to HPV16/18 was 61.4%; 95% CI, 54.3%-67.6%. However, the effectiveness against HPV16/18 was significantly higher among women vaccinated before their sexual debut 91.5%; 95% CI, 86.8-94.5, compared with effectiveness for vaccination after their sexual debut, 36.2%; 95% CI, 23.6-46.7. Five years after the introduction of HPV vaccines in Colombia, high effectiveness of HPV to prevent HPV16/18 infections is observed in the catch-up cohorts including virgin and sexually active women. PREVENTION RELEVANCE: Monitoring HPV vaccines post-licensure plays an important role in assessing the progress of immunization programs, demonstrating the impact of vaccines on the population, and providing data for policy needs. In Colombia, HPV vaccines showed effectiveness when administered before start of sexual activity, and two doses are sufficient to achieve good protection.

Prevalence of vaccine and non-vaccine human papillomavirus types among women in Accra and Kumasi, Ghana: a cross-sectional study

BACKGROUND

Human Papillomavirus (HPV) infection is the main etiological factor for pre-invasive and invasive cervical cancer. HPV type-specific vaccination is being widely recommended to control the burden of disease, but the genotype-specific distribution of HPV may vary in different countries. The aim of the study was to determine the prevalence and distribution of HPV genotypes among women attending reproductive health services in Ghana, their associated risk factors, and to assess the potential coverage of identified HPV genotypes by three licensed vaccines among these women.

METHOD

Women presenting for reproductive health services in two regional hospitals in Accra and Kumasi from October 2014 to March 2015 were conveniently recruited into the study (n = 317). HPV-DNA detection and genotype identification were carried out by a nested multiplex PCR assay that combines degenerate E6/E7 consensus primers and type-specific primers for the detection and typing of eighteen HPV genotypes. Cytology was performed to screen women for cervical cancer lesions. Risk factors for HPV infection were analyzed by logistic regression. Statistical significance was accepted for p < 0.05.

RESULTS

The age of study participants ranged from 21 to 76 years. Among women positive for HPV, 35.0% were infected with high-risk HPV, 14.5% with probable high-risk HPV, and 17.0% with low-risk HPV. The prevalence of HPV 16/18 was 8.2%, HPV 6/11/16/18 was 9.1% and HPV 6/11/16/18/31/33/45/52/58 was 28.4%. The most prevalent among HR-HPV were types 52 (18.3%) and 58 (8.8%). HPV positivity may be associated with educational background (p < 0.001), age at first pregnancy (p = 0.028), and age at coitarche (p = 0.016).

CONCLUSIONS

Our study revealed a high prevalence of HR-HPV infection among women. The high prevalence of HR HPV indicates that multivalent vaccines will be useful for controlling HPV burden in general population contexts. The distribution of HPVs in this population suggests that of the three currently available vaccines the nonavalent vaccine, which protects against seven HPV types in addition to HPV 16 and 18, has the highest coverage of HPV infections among Ghanaian women. Healthcare officials planning to reduce the transmission of HPV and cervical cancer must consider the coverage of the nonavalent vaccine as an advantage.

Reduction of HPV16/18 prevalence in young women after eight years of three- and two-dose vaccination schemes

BACKGROUND

Recommendations for human papillomavirus vaccination have relied on immunogenicity studies and efficacy results derived from adult women. Insufficient information exists regarding HPV effectiveness in vaccinated girls as they become sexually active, regardless of dose scheme. We aimed to compare the prevalence of high-risk HPV between unvaccinated and vaccinated young women eight years after immunization.

METHODS

After eight years, we recontacted women who received two-dose of bivalent or three-dose-either bivalent or quadrivalent-, HPV vaccine when aged 9-10 years-old as part of a clinical trial. Additionally, we recruited a contemporaneous unvaccinated woman group for comparison. Only those sexually active were included. High-risk HPV DNA was determined in urine samples and compared across groups.

RESULTS

The prevalence of HPV16/18 types was 6.8% (95 %CI 3.2-14.1%) in the unvaccinated (n = 6/88), 1.1% (95 %CI 0.2-5.8%) in the three-dose (n = 1/93), and 0.0% (95 %CI 0.0-7.0%) in the two-dose group (n = 0/51).

CONCLUSION

HPV vaccination, with two-dose of bivalent or three-dose schemes-either with the bivalent or quadrivalent vaccine-, was associated with a lower prevalence of HPV16/18 types eight years after primary immunization.

Postvaccination prevalence of vaccine-Human Papillomavirus (vHPV) genotypes among the target population: A systematic review and meta-analysis

Human Papillomavirus (HPV) vaccines are safe and are highly effective in reducing the prevalence of HPV infections and subsequent HPV associated diseases in the target population. A systematic review and meta-analysis was carried out searching electronic databases for articles published between January 2007 and September 2020 reporting the prevalence estimates of vaccine HPV (vHPV) types in women who had received one or more doses of quadrivalent or bivalent vaccines. This systematic review was based on standard systematic review guidelines and the meta-analysis was performed by pooling the HPV vaccine type prevalence data with 95% confidence interval (CI) among 16,929 young women who had received the prophylactic HPV vaccines before the age of 27 years. The overall pooled prevalence of vHPV types was.0.04 (95% CI: 0.02, 0.05). The meta-analysis concludes that prophylactic HPV vaccination before the age of 27 years results in a decline of vHPV types in young women.

Systematic literature review of cross-protective effect of HPV vaccines based on data from randomized clinical trials and real-world evidence

BACKGROUND

The extent of cross-protection provided by currently licensed bivalent and quadrivalent HPV vaccines versus direct protection against HPV 31-, 33-, 45-, 52-, and 58-related disease is debated. A systematic literature review was conducted to establish the duration and magnitude of cross-protection in interventional and observational studies.

METHODS

PubMed and Embase databases were searched to identify randomized controlled trials (RCT) and observational studies published between 2008 and 2019 reporting on efficacy and effectiveness of HPV vaccines in women against non-vaccine types 31, 33, 45, 52, 58, and 6 and 11 (non-bivalent types). Key outcomes of interest were vaccine efficacy against 6- and 12-month persistent infection or genital lesions, and type-specific genital HPV prevalence or incidence. RCT data were analyzed for the according-to-protocol (bivalent vaccine) or negative-for-14-HPV-types (quadrivalent vaccine) efficacy cohorts.

RESULTS

Data from 23 RCTs and 33 observational studies evaluating cross-protection were extracted. RCTs assessed cross-protection in post-hoc analyses of small size subgroups. Among fully vaccinated, baseline HPV-naïve women, the bivalent vaccine showed statistically significant cross-protective efficacy, although with wide confidence intervals, against 6-month and 12-month persistent cervical infections and CIN2+ only consistently for HPV 31 and 45, with the highest effect observed for HPV 31 (range 64.6% [95% CI: 27.6 to 83.9] to 79.1% [97.7% CI: 27.6 to 95.9] for 6-month persistent infection; maximal follow-up 4.7 years). No cross-protection was shown in extended follow-up. The quadrivalent vaccine efficacy reached statistical significance for HPV 31 (46.2% [15.3-66.4]; follow-up: 3.6 years). Similarly, observational studies found consistently significant effectiveness only against HPV 31 and 45 with both vaccines.

CONCLUSIONS

RCTs and observational studies show that cross-protection is inconsistent across non-vaccine HPV types and is largely driven by HPV 31 and 45. Furthermore, existing data suggest that it wanes over time; its long-term durability has not been established.

Impact and cost-effectiveness of strategies to accelerate cervical cancer elimination: A model-based analysis

Following the global call for action by the World Health Organization to eliminate cervical cancer (CC), we evaluated how each CC policy decision in Norway influenced the timing of CC elimination, and whether introducing nonavalent human papillomavirus (HPV) vaccine would accelerate elimination timing and be cost-effective. We used a multi-modeling approach that captured HPV transmission and cervical carcinogenesis to estimate the CC incidence associated with six past and future CC prevention policy decisions compared with a pre-vaccination scenario involving 3-yearly cytology-based screening. Scenarios examined the introduction of routine HPV vaccination of 12-year-old girls with quadrivalent vaccine in 2009, a temporary catch-up program for females aged up to 26 years in 2016-2018 with bivalent vaccine, the universal switch to bivalent vaccine in 2017, expansion to include 12-year-old boys in 2018, the switch from cytology- to HPV-based screening for women aged 34-69 in 2020, and the potential switch to nonavalent vaccine in 2021. Introducing routine female vaccination in 2009 enabled elimination to be achieved by 2056 and prevented 17,300 cases. Cumulatively, subsequent policy decisions accelerated elimination to 2039. According to our modeling assumptions, switching to the nonavalent vaccine would not be considered 'good value for money' at relevant cost-effectiveness thresholds in Norway unless the incremental cost was $19 per dose or less (range: $17-24) compared to the bivalent vaccine. CC control policies implemented over the last decade in Norway may have accelerated the timeframe to elimination by more than 17 years and prevented over 23,800 cases by 2110.

Risk factors for type-specific persistence of high-risk human papillomavirus and residual/recurrent cervical intraepithelial neoplasia after surgical treatment

Objective

This study aimed to investigate the clinicopathologic risk factors for type-specific persistence of high-risk human papillomavirus (hrHPV) and residual/recurrent cervical intraepithelial neoplasia (CIN) after surgical treatment.

Methods

Patients with CIN-2/3 who underwent conization or loop electrosurgical excision procedure (LEEP) at Korea University Hospital were enrolled. All patients underwent hrHPV testing and genotyping before conization or LEEP followed by both hrHPV genotyping and cytology. The significance of associations between patient characteristics and persistence of infection were assessed by multivariate logistic regression analyses.

Results

Among 398 women with pathologically confirmed CIN-2/3, 154 (38.7%) patients showed hrHPV persistence after surgical treatment. In multivariate analysis, high preoperative hrHPV load (P<0.05; odds ratio [OR], 2.063), presence of CIN-2 at treatment (P<0.01; OR, 2.732), and multiple hrHPV infections (P<0.001; OR, 4.752) were associated with hrHPV persistence. HPV 53 was the most likely to persist after treatment (24/43, 55.8%). The risk of residual/recurrent CIN-2/3 was higher in persistent infection with HPV 16 than other types (P<0.05). Menopause (P<0.001; OR, 3.969), preoperative and postoperative hrHPV load (P<0.05; OR, 2.430; P<0.05; OR, 5.351), and infection with multiple hrHPV types (P<0.05; OR, 2.345) were significantly related to residual/recurrent CIN following surgical treatment.

Conclusion

HPV load before treatment and infection with multiple hrHPV types were predictors of postoperative hrHPV persistence. HPV 53 was the type most likely to persist, but HPV 16 was the type that was most closely associated with residual/recurrent CIN-2/3.

Multi-Infection Patterns and Co-infection Preference of 27 Human Papillomavirus Types Among 137,943 Gynecological Outpatients Across China

Background: The epidemiological feature of human papillomavirus (HPV) infection is distinctive in China. We aimed to investigate the multi-infection patterns and co-infection preference of 27 HPV types among gynecological outpatients across China.

Methods: Overall 137,943 gynecological outpatients were recruited from eight tertiary hospitals located in seven regions of China, between July 1st, 2014 and December 31st, 2016. The overall, region-specific, age-specific and type-specific prevalence of HPV infection were calculated, respectively. The pattern of HPV infection was also evaluated. Furthermore, rate ratio was calculated to evaluate the co-infection preference of any two HPV genotypes.

Results: The overall prevalence of 27 HPVs' [17 high-risk (hr)/10 low-risk (lr)] infection was 23.5%. The age-specific HPV prevalence showed a “U-shaped” pattern. The most prevalent hrHPV genotypes were 16, 52, and 58. Multiple infections were detected in 25.8% of the HPV-positive women, in which dual infection was more prevalent. HPV 16/18 were likely to co-infected with HPV 31 but unlikely with HPV 52/58, i.e., the co-infection of HPV 16 with HPV 31 was high (3.5-fold), but low for HPV 58 (1.8-fold), and 52 (1.2-fold), while the co-infection of HPV 18 with HPV 31 was high (4.3-fold), but low for HPV 52 (1.9-fold), and 58 (1.7-fold).

Conclusions: We found age-specific prevalence of HPV infection showed a “U-shaped” pattern for high and low risk HPV, suggesting the importance of screening among younger women and the necessary of detection among older women. We found a novel co-infection preference of HPV 16/18 with 31, 52, and 58, suggesting a need of developing and marketing prophylactic HPV vaccines that protect against more genotypes in China.

Capturing multiple-type interactions into practical predictors of type replacement following human papillomavirus vaccination

Current HPV vaccines target a subset of the oncogenic human papillomavirus (HPV) types. If HPV types compete during infection, vaccination may trigger replacement by the non-targeted types. Existing approaches to assess the risk of type replacement have focused on detecting competitive interactions between pairs of vaccine and non-vaccine types. However, methods to translate any inferred pairwise interactions into predictors of replacement have been lacking. In this paper, we develop practical predictors of type replacement in a multi-type setting, readily estimable from pre-vaccination longitudinal or cross-sectional prevalence data. The predictors we propose for replacement by individual non-targeted types take the form of weighted cross-hazard ratios of acquisition versus clearance, or aggregate odds ratios of coinfection with the vaccine types. We elucidate how the hazard-based predictors incorporate potentially heterogeneous direct and indirect type interactions by appropriately weighting type-specific hazards and show when they are equivalent to the odds-based predictors. Additionally, pooling type-specific predictors proves to be useful for predicting increase in the overall non-vaccine-type prevalence. Using simulations, we demonstrate good performance of the predictors under different interaction structures. We discuss potential applications and limitations of the proposed methodology in predicting type replacement, as compared to existing approaches. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

Can the prophylactic quadrivalent HPV vaccine be used as a therapeutic agent in women with CIN? A randomized trial

Background

Human papillomavirus (HPV) is one of the most significant risk factors for cervical cancer. The HPV vaccine has a very significant impact on the incidence of cervical cancer. The present study aimed to investigate the impact of prophylactic quadrivalent HPV vaccine in the treatment of women with cervical intraepithelial neoplasia (CIN 1–3).

Methods

This randomized controlled trial was conducted in the Shahid Sadoughi University of Medical Sciences (SSUMS), Yazd, Iran, from October 2011 to November 2015 in women with histologically confirmed residual/recurrent CIN 1 or high-grade CIN (CIN 2–3). Eligible women were assigned randomly to an intervention and a control group. Women in the intervention group were given HPV vaccinations while those in the control group were not. Participants were followed up for 24 months. Primary and secondary outcomes, and adverse effects of the treatment in the two groups were compared using Student’s t test, the chi-square test, or Fisher’s exact test. P values < 0.05 or less were considered statistically significant.

Results

Three-hundred and twelve women were randomized to the two groups; the data of 138 in the intervention group and 104 in the control group were analyzed. The mean age of the women was 32.59 ± 4.85 years. Differences in age, marital status, and grades of CIN weren’t significant between the two groups. At the end of the two-year follow-up period, the number of women with CIN 2–3 in the intervention and control groups was reduced by 75% (from 93 to 23) versus 40% (from 69 to 41). The efficacy of the HPV vaccine in women with CIN 1–3 was 58.7% (p = 0.018). No serious adverse effects related to the vaccines were reported.

Conclusions

The prophylactic quadrivalent HPV vaccine after treatment may have a therapeutic effect in women with residual/recurrent CIN 1 or high-grade CIN (CIN 2–3).

Trial registration

Iranian Registry of Clinical Trials, IRCT20190603043801N1. Registered 24 July 2019 – Retrospectively registered, http://www.irct.ir/user/trial/40017/view

Efficacy and immunogenicity of a single dose of human papillomavirus vaccine compared to no vaccination or standard three and two-dose vaccination regimens: A systematic review of evidence from clinical trials

OBJECTIVES

This study aimed to systematically review the literature on the efficacy and immunogenicity of single-dose HPV vaccination compared to no vaccination or multi-dose schedules among vaccine trial participants.

METHODS

Medline, EMBASE, Global Health Database and Cochrane Central Register of Controlled Trials were searched for publications and conference abstracts (dated January 1999-August 2018) using MeSH and non-MeSH terms for human papillomavirus AND vaccines AND (immunogenicity OR efficacy/effectiveness) AND dosage. Search results were screened against pre-specified eligibility criteria. Data were extracted from included articles, and a narrative synthesis conducted on efficacy against HPV16/18 infection and humoral immunogenicity.

RESULTS

Seven of 6,523 unique records identified were included in the review. Six were nested observational studies of participants randomised to receive two or three doses in three large HPV vaccine trials, in which some participants did not complete their allocated schedules. One small pilot study prospectively allocated participants to receive one or no vaccine dose. Frequency of HPV16/18 infection was low (e.g. <1% for 12-month-persistent infection) in all vaccinated participants up to seven years post vaccination and did not significantly differ by number of doses (p > 0.05 in all cases). Frequency of infection was significantly lower in one-dose recipients compared to unvaccinated controls (p < 0.01 for all infection endpoints in each study). HPV16/18 seropositivity rates were high in all HPV vaccine recipients (100% in three of four studies reporting this endpoint), though antibody levels were lower with one compared to two or three doses.

CONCLUSIONS

This review supports the premise that one HPV vaccine dose may be as effective in preventing HPV infection as multi-dose schedules in healthy young women. However, it also highlights the paucity of available evidence from purpose-designed, prospectively-randomised trials. Results from ongoing clinical trials assessing the efficacy and immunogenicity of single-dose HPV vaccination compared to currently-recommended schedules are awaited.

Prevalence of Human Papillomavirus (HPV) and Other Sexually Transmitted Infections (STIs) among Italian Women Referred for a Colposcopy

Sexually transmitted infections (STIs) represent a major cause of morbidity in women and men worldwide. Human Papillomavirus (HPV) infections are among the most prevalent STIs and persistent infections with high-risk HPV (hrHPV) genotypes can cause cervical dysplasia and invasive cervical cancer. The association of other STIs with HPV cervical infection and/or dysplasia has however not yet been fully elucidated. The aim of this study was to assess the prevalence of HPV and other STIs among women presenting with an abnormal cervical cytology. Cervical infections with 28 HPV genotypes and seven other sexually transmitted pathogens were evaluated in 177 women referred for a colposcopy after an abnormal Pap smear. Positivity for at least one hrHPV genotype was shown in 87% of women; HPV 16 was the most prevalent (25.0%), followed by HPV 31 and HPV 51. The overall positivity for other STIs was 49.2%, with Ureaplasma parvum being the most prevalent microrganism (39.0%). Co-infections between hrHPV and other STIs were demonstrated in 17.5% of women; no significant association was demonstrated between multiple infections and the colposcopy findings. This study provides new epidemiological data on the prevalence of cervical infections associated with HPV and seven other common sexually transmitted pathogens in a population of women presenting with an abnormal cervical cytology.

Human Papillomavirus Vaccine Effectiveness Against HPV Infection: Evaluation of One, Two, and Three Doses

Background

Highly effective human papillomavirus (HPV) vaccines are used in many national programs in 3- or 2-dose schedules. We examined HPV vaccine effectiveness against HPV prevalence by number of doses.

Methods

We collected residual liquid-based cytology samples from US women aged 20–29 years who were screened for cervical cancer. Women continuously enrolled from 2006 through the specimen collection date were analyzed. Specimens were tested using the Linear Array assay. We analyzed prevalence of quadrivalent HPV vaccine (4vHPV) types (HPV 6,11,16,18) and other HPV-type categories and determined prevalence ratios (PRs) and 95% confidence intervals (CIs) for 1, 2, and 3 compared with no vaccine doses.

Results

Among 4269 women, 1052 (24.6%) were unvaccinated, 2610 (61.1%) received 3 doses, 304 (7.1%) received 2 doses, and 303 (7.1%) received 1 dose. The 4vHPV-type prevalence was 7.4% among unvaccinated women compared with 1.7%, 1.0%, and 1.0% among 1-, 2-, and 3-dose recipients. Among women vaccinated at ≤18 years, adjusted PRs for 1, 2, and 3 doses were 0.06 (95% CI, 0.01–0.42), 0.05 (95% CI, 0.01–0.39), and 0.06 (95% CI, 0.04–0.12).

Conclusions

Among women who received their first dose at age ≤18, estimated HPV vaccine effectiveness was high regardless of number of doses.

Human Papillomavirus (HPV) Vaccine Effectiveness and Potential Herd Immunity for Reducing Oncogenic Oropharyngeal HPV-16 Prevalence in the United Kingdom: A Cross-sectional Study

BACKGROUND

Oropharyngeal cancer incidence is rapidly rising due to human papillomavirus (HPV) type 16 infection. The dearth of data on effectiveness of national female-only vaccination programs in preventing oral HPV infection and potential herd immunity in unvaccinated males has resulted in considerable controversy regarding the need to vaccinate males, especially in countries with high female vaccination coverage.

METHODS

Subjects aged 0-65 years undergoing tonsillectomy for nonmalignant indications were recruited in 6 hospitals in the United Kingdom. Oral samples were collected as follows: oral rinse, tongue base, and pharyngeal wall brushes, then tonsil tissue (tonsillectomy). Vaccination data were obtained from regional health authorities. All samples were centrally tested for HPV DNA by polymerase chain reaction.

RESULTS

Of 940 subjects, 243 females and 69 males were aged 12-24 years (median age, 18.6 years), with 189 (78%) females and no males vaccinated against HPV. Overall, oropharyngeal HPV-16 prevalence was significantly lower in vaccinated versus unvaccinated females (0.5% vs 5.6%, P = .04). In contrast, prevalence of any oropharyngeal HPV type was similar in vaccinated and unvaccinated females (19% vs 20%, P = .76). Oropharyngeal HPV-16 prevalence in unvaccinated males was similar to vaccinated females (0% vs 0.5%, P > .99), and lower than unvaccinated females (0% vs 5.6%, P = .08).

CONCLUSIONS

Our findings indicate that the UK female-only vaccination program is associated with significant reductions in oropharyngeal HPV-16 infections. These are also the first data to suggest potential herd immunity from female-only vaccination against oropharyngeal HPV infection in contemporaneously aged males.

Facilitators and barriers of human papillomavirus vaccine uptake in young females 18-26 years old in Singapore: A qualitative study

BACKGROUND

Around 70% of cervical cancers are caused by Types 16 and 18 of human papillomavirus (HPV). Vaccines against HPV have been shown to be safe and effective in preventing HPV and cervical cancer.

OBJECTIVE

To explore the facilitators and barriers of HPV vaccination in young females aged 18-26 years in Singapore, and to describe their recommended strategies to improve the uptake of HPV vaccination.

DESIGN

Qualitative, descriptive design guided by the socio-ecological model.

PARTICIPANTS

Young women studying in National University of Singapore (NUS), aged 18-26 (N = 40). Purposive sampling was used to recruit participants from various socio-economic levels and faculties, both vaccinated against HPV and unvaccinated.

METHODS

In-depth interviews (IDIs) and focus group discussions (FGDs) were conducted with the participants. IDIs and FGDs were transcribed and coded using NVIVO software. Thematic data analysis was performed using an inductive approach.

RESULTS

Barriers to HPV vaccination included lack of awareness, lack of perceived risk for cervical cancer, cost, lack of parental support, inconvenience of getting the vaccination, stigma associated with connection with sexual activity, and concern regarding safety. Facilitators include parental encouragement, protection of one's health, lack of logistical barriers, and perceived safety and efficacy of the vaccine. Participants recommended increasing awareness of HPV vaccination and cervical cancer, reducing cost of vaccination and making the vaccine compulsory to increase vaccine uptake.

CONCLUSION

Barriers and facilitators exist at different levels to influence vaccine uptake. Public education on cervical cancer and the vaccine should be stepped up to increase public awareness. A school-based national vaccination programme was proposed by the target group to increase the rate of uptake of HPV vaccination in Singapore.

CDS-1548 induces apoptosis in HeLa cells by activating caspase 3

Cervical cancer continues to be a threat to female health globally. In the present study, the potential anticancer activity of 2-[2-hydroxyl-1-(4-methoxy phenyl) ethyl]-3-(4-benzyloxy phenyl) isoindolin-1-one (CDS-1548), was evaluated in HeLa cells. CDS-1548 is an organic small-molecule compound characterized by two chiral centers, with the nuclear parent 1H-isoindolin-1-one. CDS-1548 administration significantly elevated the transcriptional activity of p53 and its downstream target genes in a dose-dependent manner. Additionally, CDS-1548 treatment increased the expression levels of p53 and mouse double minute 2 homolog, as well as inducing apoptosis in HeLa cells. Furthermore, CDS-1548 treatment downregulated the expression of B-cell lymphoma 2, upregulated Bcl-2 homologous antagonist killer, promoted the release of cytochrome c from mitochondria to cytoplasm, and activated the production of caspase 3 and 9. Collectively, these results suggested that CDS-1548 inhibited HeLa cell proliferation by promoting G₂/M cell cycle phase arrest and inducting of mitochondria-mediated apoptosis.

Population-level impact and herd effects following the introduction of human papillomavirus vaccination programmes: updated systematic review and meta-analysis

BACKGROUND

More than 10 years have elapsed since human papillomavirus (HPV) vaccination was implemented. We did a systematic review and meta-analysis of the population-level impact of vaccinating girls and women against human papillomavirus on HPV infections, anogenital wart diagnoses, and cervical intraepithelial neoplasia grade 2+ (CIN2+) to summarise the most recent evidence about the effectiveness of HPV vaccines in real-world settings and to quantify the impact of multiple age-cohort vaccination.

METHODS

In this updated systematic review and meta-analysis, we used the same search strategy as in our previous paper. We searched MEDLINE and Embase for studies published between Feb 1, 2014, and Oct 11, 2018. Studies were eligible if they compared the frequency (prevalence or incidence) of at least one HPV-related endpoint (genital HPV infections, anogenital wart diagnoses, or histologically confirmed CIN2+) between pre-vaccination and post-vaccination periods among the general population and if they used the same population sources and recruitment methods before and after vaccination. Our primary assessment was the relative risk (RR) comparing the frequency (prevalence or incidence) of HPV-related endpoints between the pre-vaccination and post-vaccination periods. We stratified all analyses by sex, age, and years since introduction of HPV vaccination. We used random-effects models to estimate pooled relative risks.

FINDINGS

We identified 1702 potentially eligible articles for this systematic review and meta-analysis, and included 65 articles in 14 high-income countries: 23 for HPV infection, 29 for anogenital warts, and 13 for CIN2+. After 5-8 years of vaccination, the prevalence of HPV 16 and 18 decreased significantly by 83% (RR 0·17, 95% CI 0·11-0·25) among girls aged 13-19 years, and decreased significantly by 66% (RR 0·34, 95% CI 0·23-0·49) among women aged 20-24 years. The prevalence of HPV 31, 33, and 45 decreased significantly by 54% (RR 0·46, 95% CI 0·33-0·66) among girls aged 13-19 years. Anogenital wart diagnoses decreased significantly by 67% (RR 0·33, 95% CI 0·24-0·46) among girls aged 15-19 years, decreased significantly by 54% (RR 0·46, 95% CI 0.36-0.60) among women aged 20-24 years, and decreased significantly by 31% (RR 0·69, 95% CI 0·53-0·89) among women aged 25-29 years. Among boys aged 15-19 years anogenital wart diagnoses decreased significantly by 48% (RR 0·52, 95% CI 0·37-0·75) and among men aged 20-24 years they decreased significantly by 32% (RR 0·68, 95% CI 0·47-0·98). After 5-9 years of vaccination, CIN2+ decreased significantly by 51% (RR 0·49, 95% CI 0·42-0·58) among screened girls aged 15-19 years and decreased significantly by 31% (RR 0·69, 95% CI 0·57-0·84) among women aged 20-24 years.

INTERPRETATION

This updated systematic review and meta-analysis includes data from 60 million individuals and up to 8 years of post-vaccination follow-up. Our results show compelling evidence of the substantial impact of HPV vaccination programmes on HPV infections and CIN2+ among girls and women, and on anogenital warts diagnoses among girls, women, boys, and men. Additionally, programmes with multi-cohort vaccination and high vaccination coverage had a greater direct impact and herd effects.

FUNDING

WHO, Canadian Institutes of Health Research, Fonds de recherche du Québec - Santé.

Efficacy, immunogenicity and safety of the AS04-HPV-16/18 vaccine in Chinese women aged 18-25 years: End-of-study results from a phase II/III, randomised, controlled trial

Background

Cervical cancer is a major public health concern in China. We report the end‐of‐study results of a phase II/III trial to assess the efficacy, immunogenicity, and safety of the AS04‐human papillomavirus (HPV)‐16/18 vaccine in Chinese women aged 18‐25 years followed for up to 72 months after first vaccination. Results of approximately 57 months following first vaccination have been previously reported.

Methods

Healthy 18‐25‐year‐old women (N = 6051) were randomized (1:1) to receive three doses of AS04‐HPV‐16/18 vaccine or Al(OH)₃ (control) at Months 0‐1‐6. Vaccine efficacy against HPV‐16/18 infection and cervical intraepithelial neoplasia (CIN), cross‐protective vaccine efficacy against infections and lesions associated with nonvaccine oncogenic HPV types, immunogenicity, and safety were assessed. Efficacy was assessed in the according‐to‐protocol efficacy (ATP‐E) cohort (vaccine N = 2888; control N = 2892), total vaccinated cohort for efficacy (TVC‐E; vaccine N = 2987; control N = 2985) and TVC‐naïve (vaccine N = 1660; control N = 1587).

Results

In initially HPV‐16/18 seronegative/DNA‐negative women, vaccine efficacy against HPV‐16/18‐associated CIN grade 2 or worse was 87.3% (95% CI: 5.5, 99.7) in the ATP‐E, 88.7% (95% CI: 18.5, 99.7) in the TVC‐E, and 100% (95% CI: 17.9, 100) in the TVC‐naïve. Cross‐protective efficacy against incident infection with HPV‐31, HPV‐33 and HPV‐45 was 59.6% (95% CI: 39.4, 73.5), 42.7% (95% CI: 15.6, 61.6), and 54.8% (95% CI: 19.3, 75.6), respectively (ATP‐E). At Month 72, >95% of initially seronegative women who received HPV vaccine in the ATP cohort for immunogenicity (N = 664) remained seropositive for anti‐HPV‐16/18 antibodies; anti‐HPV‐16 and anti‐HPV‐18 geometric mean titers were 678.1 EU/mL (95% CI: 552.9, 831.5) and 343.7 EU/mL (95% CI: 291.9, 404.8), respectively. Serious adverse events were infrequent (1.9% vaccine group [N = 3026]; 2.7% control group [N = 3025]). Three and zero women died in the control group and the vaccine group respectively. New onset autoimmune disease was reported in two women in the vaccine group and two in the control group.

Conclusions

This is the first large‐scale randomized clinical trial of HPV vaccination in China. High and sustained vaccine efficacy against HPV‐16/18‐associated infection and cervical lesions was demonstrated up to Month 72. The vaccine had an acceptable safety profile. Combined with screening, prophylactic HPV vaccination could potentially reduce the high burden of HPV infection and cervical cancer in China.

Trial registration

NCT00779766.

Novel Approaches for Vaccination Against HPV-Induced Cancers

To date, more than 5 % of all cancers are as a result of human papillomavirus (HPV) infection, and this incidence is increasing. Early recognition of disease is associated with good survival, but late presentation results in devastating consequences. Prevention is better than cure, and there are now successful prophylactic vaccination programmes in place. We discuss these and the prospect of therapeutic vaccinations in the near future to address a growing need for improved therapeutic options.

[Human papillomavirus vaccine receptivity: a systematic reviewReceptividad con respecto a la vacuna contra el virus del papiloma humano: revisión sistemática]

Objetivo.

Caracterizar a receptividade à vacina contra o papilomavírus humano (HPV) e descrever as barreiras e os facilitadores dessa receptividade.

Métodos.

Trata-se de uma revisão sistemática conforme o protocolo PRISMA 2015. Os repositórios MEDLINE e Web of Science foram consultados utilizando combinações dos termos papillomavirus, vaccine, adherence e acceptance para identificar artigos publicados de 2006 a 2017. Foram incluídos artigos originais em qualquer idioma e excluídos artigos duplicados. Foram analisadas identificação do artigo, tipificação metodológica e caracterização da amostra. A receptividade foi caracterizada em termos de aceitação e adesão.

Resultados.

Foram identificados 212 artigos, sendo 10 selecionados para análise. A maioria dos estudos evidenciou receptividade favorável, porém heterogênea, havendo maior aceitação do que adesão, principalmente por adolescentes do sexo feminino. Foram identificados 11 facilitadores e nove barreiras à receptividade, com destaque para conhecimento relativo ao tema e padrão de comportamento individual frente ao problema. Observou-se a inexistência de um método padronizado que avalie a temática e a imprecisão dos conceitos associados a aceitação e adesão. Diante disso, o estudo propôs conceitos de aceitação (intenção voluntária de receber uma vacina ou concordar que a mesma representa uma boa estratégia preventiva) e adesão (ato de iniciar a vacinação e completar o esquema).

Conclusões.

Novos estudos são necessários para aprofundar a análise dos preditores da receptividade. Sugere-se a construção de um instrumento baseado na percepção do público alvo e em conceitos precisos de aceitação e adesão, que possibilite melhor compreensão do fenômeno e estimule a adesão e o alcance de coberturas vacinais adequadas.

Non-Vaccine-Type Human Papillomavirus Prevalence After Vaccine Introduction: No Evidence for Type Replacement but Evidence for Cross-Protection

BACKGROUND

We examined non-vaccine-type human papillomavirus (HPV) prevalence in a community before and during the first 8 years after vaccine introduction, to assess for (1) type replacement with any non-vaccine-type HPV and (2) cross-protection with non-vaccine types genetically related to vaccine-type HPV.

METHODS

Sexually experienced 13- to- 26-year-old women were recruited for 3 cross-sectional studies from 2006 to 2014 (N = 1180). Outcome variables were as follows: (1) prevalence of at least 1 of 32 anogenital non-vaccine-type HPVs and (2) prevalence of at least 1 HPV type genetically related to HPV-16 and HPV-18. We determined changes in proportions of non-vaccine-type HPV prevalence across the study waves using logistic regression with propensity score inverse probability weighting.

RESULTS

Vaccine initiation rates increased from 0% to 71.3%. Logistic regression demonstrated that from 2006 to 2014, there was no increase in non-vaccine-type HPV among vaccinated women (adjusted odds ratio [AOR], 1.02; 95% confidence interval [CI], 0.73-1.42), but an increase among unvaccinated women (AOR, 1.88; 95% CI, 1.16-3.04). Conversely, there was a decrease in types genetically related to HPV-16 among vaccinated (AOR, 0.57; 95% CI, 0.38-0.88) but not unvaccinated women (AOR, 1.33; 95% CI, 0.81-2.17).

CONCLUSIONS

We did not find evidence of type replacement, but did find evidence of cross-protection against types genetically related to HPV-16. These findings have implications for cost-effectiveness analyses, which may impact vaccine-related policies, and provide information to assess the differential risk for cervical cancer in unvaccinated and vaccinated women, which may influence clinical screening recommendations. The findings also have implications for public health programs, such as health messaging for adolescents, parents, and clinicians about HPV vaccination.

Prevalence of cervical disease at age 20 after immunisation with bivalent HPV vaccine at age 12-13 in Scotland: retrospective population study

OBJECTIVE

To quantify the effect on cervical disease at age 20 years of immunisation with bivalent human papillomavirus (HPV) vaccine at age 12-13 years.

DESIGN

Retrospective population study, 1988-96.

SETTING

National vaccination and cervical screening programmes in Scotland.

PARTICIPANTS

138 692 women born between 1 January 1988 and 5 June 1996 and who had a smear test result recorded at age 20.

MAIN OUTCOME MEASURES

Effect of vaccination on cytology results and associated histological diagnoses from first year of screening (while aged 20), calculated using logistic regression.

RESULTS

138 692 records were retrieved. Compared with unvaccinated women born in 1988, vaccinated women born in 1995 and 1996 showed an 89% reduction (95% confidence interval 81% to 94%) in prevalent cervical intraepithelial neoplasia (CIN) grade 3 or worse (from 0.59% (0.48% to 0.71%) to 0.06% (0.04% to 0.11%)), an 88% reduction (83% to 92%) in CIN grade 2 or worse (from 1.44% (1.28% to 1.63%) to 0.17% (0.12% to 0.24%)), and a 79% reduction (69% to 86%) in CIN grade 1 (from 0.69% (0.58% to 0.63%) to 0.15% (0.10% to 0.21%)). Younger age at immunisation was associated with increasing vaccine effectiveness: 86% (75% to 92%) for CIN grade 3 or worse for women vaccinated at age 12-13 compared with 51% (28% to 66%) for women vaccinated at age 17. Evidence of herd protection against high grade cervical disease was found in unvaccinated girls in the 1995 and 1996 cohorts.

CONCLUSIONS

Routine vaccination of girls aged 12-13 years with the bivalent HPV vaccine in Scotland has led to a dramatic reduction in preinvasive cervical disease. Evidence of clinically relevant herd protection is apparent in unvaccinated women. These data are consistent with the reduced prevalence of high risk HPV in Scotland. The bivalent vaccine is confirmed as being highly effective vaccine and should greatly reduce the incidence of cervical cancer. The findings will need to be considered by cervical cancer prevention programmes worldwide.

Human Papillomavirus Vaccine Effectiveness and Herd Protection in Young Women

BACKGROUND

Clinical trials of the 4-valent human papillomavirus (HPV) vaccine demonstrate high efficacy, but surveillance studies are essential to examine the long-term impact of vaccine introduction on HPV prevalence in community settings. The aims of this study were to determine during the 11 years after vaccine introduction the prevalence of (1) vaccine-type HPV in adolescent and young adult women who were vaccinated (to assess vaccine effectiveness) and (2) vaccine-type HPV in women who were unvaccinated (to assess herd protection).

METHODS

Young women 13 to 26 years of age were recruited from hospital-based and community health clinics for 4 surveillance studies from 2006 to 2017. We determined the proportion of vaccinated and unvaccinated women who were positive for vaccine-type HPV across the studies, and the odds of positivity for vaccine-type HPV using logistic regression; all analyses were propensity score-adjusted to control for between-wave differences in participant characteristics.

RESULTS

Vaccination rates increased from 0% to 84.3% (97% of study participants received the 4-valent vaccine). Among women who were vaccinated, 4-valent vaccine-type HPV detection decreased from 35% to 6.7% (80.9% decline; odds ratio 0.13, 95% confidence interval 0.08 to 0.22). Among women who were unvaccinated, 4-valent vaccine-type HPV detection decreased from 32.4% to 19.4% (40% decline; odds ratio 0.50, 95% confidence interval 0.26 to 0.97). Estimated vaccine effectiveness was 90.6% in wave 3 and 80.1% in wave 4.

CONCLUSIONS

In this study in which trends in HPV in a US community >10 years after 4-valent HPV vaccine introduction and after 9-valent vaccine introduction were examined, we found evidence of vaccine effectiveness and herd protection. Further research is needed to examine trends in 9-valent vaccine-type HPV after higher rates of vaccination are achieved.

Clinical performance of Anyplex II HPV28 by human papillomavirus type and viral load in a referral population

Anyplex II HPV28 (`Anyplex`) is a semi-quantitative DNA PCR assay divided into set A, comprising 14 high risk (hr)HPV types; and set B, comprising 5 possibly hrHPV types and 9 low risk (lr)HPV types. We compared the ability of Anyplex to that of Hybrid Capture 2 (HC2) and PreTect HPV-Proofer (`Proofer`) to detect cervical intraepithelial neoplasia grade two or worse (CIN2+) by HPV types and viral load. This cross-sectional study included 296 women referred to colposcopy with abnormal cervical cytology and/or persistent HPV infection. CIN2+ was identified in 175/296 women. Liquid based cytology samples were used to perform HPV testing. The sensitivity of Anyplex to detect CIN2+ was 98.9% (95% CI 95.9–99.9) and specificity 43.0% (95% CI 34.0–52.3). Restricting to medium and high viral loads in Anyplex set A, sensitivity and specificity were 97.1% (95% CI 93.5–99.1) and 59.5% (95% CI 50.2–68.3) with positive (PPV) and negative predictive value (NPV) 77.6% and 93.5%, respectively, comparable to HC2. Restricting Anyplex to the hrHPV types in Proofer, HPV16, 18, 31, 33 and 45, sensitivity and specificity for CIN2+ were 85.1% (95% CI 79.0–90.1) and 71.1% (95% CI 62.1–79.0), comparable to Proofer`s. When adding HPV52 and 58, the sensitivity for CIN2+ was 92.6% (95% CI 87.6–96.0) and CIN3+ 96.5% (95% CI 92.0–98.8). No value of Anyplex set B was found in detecting CIN2+. In conclusion, the clinical performance of medium and high viral loads in Anyplex set A was comparable to HC2. Restricting the test to the 7 hrHPV types included in the 9-valent HPV-vaccine, HPV16, 18, 31, 33, 45, 52 and 58, satisfies the international criteria for cervical cancer screening with relative sensitivity compared to HC2 for CIN2+ and CIN3+ of 0.98 and 1.01, respectively. Detecting all 28 Anyplex HPV types adds no benefit in a referral population.

Ten years of HPV vaccination in the Netherlands: current evidence and future challenges in HPV-related disease prevention

INTRODUCTION

Girls-only vaccination against human papillomavirus (HPV) type 16 and 18 was implemented in the Netherlands in 2009. Despite the evidence of the efficacy against precancerous lesions, cross-protection induced by the vaccine and a greater potential for cancer prevention than cervical cancer only, vaccine coverage in the girls-only program has remained below target levels.

AREAS COVERED

In this paper, we review the literature from the Netherlands on the effectiveness and cost-effectiveness of HPV vaccination since vaccine introduction, give an account of the coverage, safety and effectiveness of HPV vaccination as has been reported in the Dutch surveillance program and discuss challenges of the current HPV vaccination program.

EXPERT COMMENTARY

Girls-only HPV vaccination may confer a substantial health gain in HPV-related disease prevention. However, vaccine coverage declined remarkably recently possibly related to safety concerns, limiting the benefits from girls' vaccination and increasing the potential additional benefit of sex-neutral HPV vaccination. Considering the emergence of novel vaccination and screening options and the change from cytology- to HPV-based screening in 2017, further research is required to inform decisions on the optimization of an integrated vaccination and screening program.

Persistence of immune response following bivalent HPV vaccination: A follow-up study among girls routinely vaccinated with a two-dose schedule

BACKGROUND

In this cohort study, we examined antibody levels and avidity after a two-dose schedule (0, 6 months) of the bivalent HPV-vaccine in girls routinely vaccinated in the Dutch HPV-vaccination program, up to 2 years following vaccination.

METHODS

A blood sample at 7, 12 and 24 months after the first dose and questionnaire data were collected (n = 56). HPV type-specific antibody concentrations (lU/ml) against seven types (HPV16/18/31/33/45/52/58) were assessed using a validated virus-like particles (VLP) multiplex immunoassay. Avidity was tested using a modification of this assay.

RESULTS

Seropositivity for vaccine types HPV 16 and 18 was 100% up to month 24, but declined for HPV-types 31/33/45/52/58, although not statistically significant for HPV45. All Geometric Mean Concentrations (GMCs) declined by months 12 and 24, but remained high for HPV16/18. Between month 7 and 12, GMCs declined more for other types. High avidity antibodies were induced up to 24 months for vaccine types (75%, 76-78% and 81-82% at months 7, 12 and 24, respectively), but for other types antibody avidity was 16-29% at month 7, 20-32% at month 12 and 19-32% at month 24.

CONCLUSIONS

GMCs declined over time for HPV-types 16/18/31/33/45/52/58, but remained high for vaccine-types HPV16/18 up to 24 months of follow-up. Antibody avidity was >75% for vaccine types but <35% for other HPV-types. Further follow-up of this cohort will provide insight into antibody and avidity kinetics over time.

Substantial Decline in Prevalence of Vaccine-Type and Nonvaccine-Type Human Papillomavirus (HPV) in Vaccinated and Unvaccinated Girls 5 Years After Implementing HPV Vaccine in Norway

Background

In 2009, quadrivalent human papillomavirus (HPV) vaccine was introduced in a school-based single-cohort program targeting 12-year-old girls in Norway. We estimated the impact of the Norwegian HPV immunization program.

Methods

Three birth cohorts of 17-year-old girls, 2 nonvaccine-eligible cohorts (born 1994 or 1996) and 1 vaccine-eligible cohort (born 1997) were invited to deliver urine samples. The samples were analyzed for 37 HPV genotypes. HPV prevalence was compared between birth cohorts and between vaccinated and unvaccinated girls within and across birth cohorts after linkage to the Norwegian Immunisation Registry.

Results

In total, 17749 urine samples were analyzed. A 42% (95% confidence interval [CI], 37%-47%) reduction in any HPV type and 81% (95% CI, 76%-85%) reduction in vaccine types (HPV-6/11/16/18) were observed in the vaccine-eligible cohort compared to the 1994 cohort. Vaccine types were reduced by 54% (95% CI, 39%-66%) and 90% (95% CI, 86%-92%) in unvaccinated and vaccinated girls, respectively, from the 1997 cohort, compared with unvaccinated girls born in 1994. A significant reduction was also observed for several nonvaccine types. Vaccine-type prevalence was reduced by 77% (95% CI, 65%-85%) in vaccinated compared with unvaccinated girls from the 1997 cohort.

Conclusions

In this largely HPV-naive population, we observed a substantial reduction in vaccine and nonvaccine types in vaccinated and unvaccinated girls following introduction of HPV vaccination.

Changes in human papillomavirus genotypes associated with cervical intraepithelial neoplasia grade 2 lesions in a cohort of young women (2013-2016)

In 2008, a quadrivalent human papillomavirus (HPV) vaccine (genotypes 6, 11, 16, 18) became available in New Zealand. This study investigated whether the proportion of cervical intraepithelial neoplasia grade 2 (CIN2) lesions associated with HPV genotypes 16 and 18 changed over time in young women recruited to a prospective CIN2 observational management trial (PRINCess) between 2013 and 2016. Partial HPV genotyping (16, 18, or other high risk HPV) was undertaken on n = 392 women under 25 years (mean age 21.8, range 17–24) with biopsy-diagnosed CIN2. High risk HPV genotypes were detected in 96% of women with CIN2 lesions. Between 2013 and 2016, the proportion of women whose liquid-based cytology samples were HPV 16 or 18 positive decreased from 43% to 13%. HPV vaccination status was known for 78% of women. Between 2013 and 2016, the proportion of HPV 16/18 positivity did not significantly change in HPV-vaccinated women, but decreased from 66% to 17% in unvaccinated women. The reducing proportion of HPV 16/18-related CIN2 in our cohort of young New Zealand women may be attributable to the introduction of a national HPV vaccination program. The substantial decrease in HPV 16/18 positivity observed in unvaccinated women is likely to be due to a herd effect.

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392 women under 25 years with CIN2 lesions were recruited between 2013 and 2016.

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HPV16/18 positivity decreased from 43% of women in 2013–13% in 2016.

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In vaccinated women, HPV16/18 positivity decreased from 17% in 2013 to 9% in 2016.

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In unvaccinated women, HPV16/18 positivity decreased from 66% in 2013 to 17% in 2016.

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Decreasing HPV16/18-related CIN2 may be due to HPV vaccination and herd effect.

Immunogenicity and safety of a mixed vaccination schedule with one dose of nonavalent and one dose of bivalent HPV vaccine versus two doses of nonavalent vaccine - A randomized clinical trial

BACKGROUND

Limited data is available on the use of different HPV vaccines in the same subjects. We evaluated the immunogenicity and safety of a mixed vaccination schedule with one dose of nonavalent (9vHPV) and one dose of bivalent vaccine (2vHPV) administered in different order versus two doses of 9vHPV vaccine.

METHODS

371 girls and boys aged 9-10 years were randomized (1:1) to receive (I) two doses of 9vHPV or (II) a mixed schedule of 2vHPV + 9vHPV or 9vHPV + 2vHPV with a 6 month interval. Antibodies to HPV were tested by ELISA in blood samples collected one or six months post-first dose and one month post-second dose.

RESULTS

Post-first dose of 9vHPV 99.4-100% of subjects were seropositive to 9 HPV types included in the vaccine. GMTs varied from 5.0 to 73.6 IU(AU)/ml depending on HPV type. Post-first dose of 2vHPV all subjects were seropositive to HPV16 and 18 (GMTs 16.7 and 11.7 IU/ml, respectively) and 50.0-76.7% were seropositive to 7 types not included in 2vHPV (GMTs varied from 0.3 to 17.5 AU/ml depending on type). Post-second dose all subjects, regardless of the study group, were seropositive to 9 HPV types included in 9vHPV. Anti-HPV16 and 18 GMTs were higher in subjects with the mixed schedule and for the other 7 HPV types higher in subjects who received two doses of 9vHPV vaccine. A higher proportion of subjects who received 2vHPV reported local or systemic adverse events than those who received 9vHPV as the first dose. Post-second dose there were no differences in reported adverse events between the two vaccines.

CONCLUSIONS

The results show the mixed HPV vaccination schedules used in this study are immunogenic and have an acceptable safety profile. Although the seroprotective threshold of antibodies remains unknown the 100% seropositivity to all 9 HPV types included in 9vHPV and the increase of GMTs observed in all study groups post-second dose administration are reassuring and suggest protection might be achieved regardless of the schedule used.

CLINICAL TRIALS REGISTRATION

Clinicaltrials.gov NCT02567955.

Can a single dose of human papillomavirus (HPV) vaccine prevent cervical cancer? Early findings from an Indian study

BACKGROUND

Human papillomavirus (HPV) vaccination is a major strategy for preventing cervical and other ano-genital cancers. Worldwide HPV vaccination introduction and coverage will be facilitated if a single dose of vaccine is as effective as two or three doses or demonstrates significant protective effect compared to 'no vaccination'.

METHODS

In a multi-centre cluster randomized trial of two vs three doses of quadrivalent HPV vaccination (Gardasil™) in India, suspension of the vaccination due to events unrelated to the study led to per protocol and partial vaccination of unmarried 10-18 year old girls leading to four study groups, two by design and two by default. They were followed up for the primary outcomes of immunogenicity in terms of L1 genotype-specific binding antibody titres, neutralising antibody titres, and antibody avidity for the vaccine-targeted HPV types and HPV infections. Analysis was per actual number of vaccine doses received. This study is registered with ISRCTN, number ISRCTN98283094; and with ClinicalTrials.gov, number NCT00923702.

FINDINGS

Of the 17,729 vaccinated girls, 4348 (25%) received three doses on days 1, 60, 180 or later, 4979 (28%) received two doses on days 1 and 180 or later, 3452 (19%) received two doses on days 1 and 60, and 4950 (28%) received one dose. One dose recipients demonstrated a robust and sustained immune response against HPV 16 and 18, albeit inferior to that of 3- or 2-doses and the antibody levels were stable over a 4 year period. The frequencies of cumulative incident and persistent HPV 16 and 18 infections up to 7 years of follow-up were similar and uniformly low in all the vaccinated study groups; the frequency of HPV 16 and 18 infections were significantly higher in unvaccinated age-matched control women than among vaccine recipients. The frequency of vaccine non-targeted HPV types was similar in the vaccinated groups but higher in the unvaccinated control women.

CONCLUSION

Our results indicate that a single dose of quadrivalent HPV vaccine is immunogenic and provides lasting protection against HPV 16 and 18 infections similar to the three- and two-dose vaccine schedules, although the study suffer from some limitations. Data on long term protection beyond 7 years against HPV infection and cervical precancerous lesions are needed before policy guidelines regarding a single dose can be formulated and implemented. Significant and long-lasting protective effect of a single dose can be a strong argument to introduce one dose of the HPV vaccine in many low income countries where the current standard of care for cervical cancer prevention is 'no intervention'.

Direct, indirect and total effectiveness of bivalent HPV vaccine in women in Galicia, Spain

Bivalent human papillomavirus (HPV) vaccine was incorporated into the childhood vaccination calendar in Galicia, Spain in 2008. The objectives of this study were to estimate direct, indirect and total effectiveness of HPV vaccine and to identify sexual habits changes in the post-vaccination period in Galicia, Spain.Endocervical scrapings of 745 women attending 7 Health Areas of the Galician Public Health Service were collected in the post-vaccination period, from 2014-2017. Two groups were studied: women born between 1989 and 1993 (n = 397) and women born in 1994 or later (n = 348). Twelve high-risk human papillomavirus (HR-HPV) genotypes were detected by Cobas® 4800 HPV test (Roche Diagnostics, Mannheim, Germany). The Linear Array® HPV Genotyping Test (Roche Diagnostics) was used for HR-HPV genotype detection other than HPV 16/18. Information about sexual habits was collected by a self-filled questionnaire. Post-vaccination data were compared to previously published pre-vaccination data obtained between 2008 and 2010 in Galicia from women of the same age (18-26 years old, n = 523). The Stata 14.2 software was employed for statistical analyses.Data from 392 unvaccinated and 353 vaccinated women were compared. For unvaccinated and vaccinated women, HPV 16/18 prevalence was 9.2% and 0.8%, respectively, and HPV 31/33/45 prevalence was 8.4% and 1.1%, respectively. Direct, indirect and total effectiveness of the HPV vaccine were (%, 95% CI): 94 (72-99), 30 (-11-56) and 95 (79-99), respectively, for HPV 16/18 and 83 (46-94), -10 (-88-33) and 84 (54-94), respectively, for HPV 31/33/45. The number of women with first intercourse before 17 years old and 3 or more sexual partners along life was higher in the post-vaccination period (p < 0.05). A positive impact of bivalent HPV vaccine was observed, both on direct and cross protection. Sexual habits could have changed in the post-vaccination period.