Bivalent Human Papillomavirus Vaccine Research Articles

Safety and immunogenicity of Innovax bivalent human papillomavirus vaccine in girls 9–14 years of age: Interim analysis from a phase 3 clinical trial

BackgroundWorld Health Organization human papillomavirus (HPV) vaccination recommendations include a single- or two-dose schedule in individuals 9–20 years old and advice for generating data on single-dose efficacy or immunobridging. The ongoing Phase 3 trial of Innovax’s bivalent (types 16 and 18) HPV vaccine (Cecolin®) assesses in low- and middle-income countries alternative dosing schedules and generates data following one dose in girls 9–14 years old. Interim data for the 6-month dosing groups are presented. MethodsIn Bangladesh and Ghana, 1,025 girls were randomized to receive either two doses of Cecolin at 6-, 12-, or 24-month intervals; one dose of Gardasil® followed by one dose of Cecolin at month 24; or two doses of Gardasil 6 months apart (referent). Serology was measured by enzyme-linked immunosorbent assay (ELISA) and, in a subset, by neutralization assays. Primary objectives include immunological non-inferiority of the Cecolin schedules to referent one month after the second dose. Safety endpoints include reactogenicity and unsolicited adverse events for 7 and 30 days post-vaccination, respectively, as well as serious adverse events throughout the study. ResultsInterim analyses included data from the two groups on a 0, 6-month schedule with 205 participants per group. One month after Dose 2, 100% of participants were seropositive by ELISA and had seroconverted for both antigens. Non-inferiority of Cecolin to Gardasil was demonstrated. Six months following one dose, over 96% of participants were seropositive by ELISA for both HPV antigens, with a trend for higher geometric mean concentration following Cecolin administration. Reactogenicity and safety were comparable between both vaccines. ConclusionsCecolin in a 0, 6-month schedule elicits robust immunogenicity. Non-inferiority to Gardasil was demonstrated one month after a 0, 6-month schedule. Immunogenicity following one dose was comparable to Gardasil up to six months. Both vaccines were safe and well tolerated (ClinicalTrials.gov No. 04508309).

Immune response following a two-dose schedule of bivalent HPV vaccination among girls and boys.

This longitudinal cohort study describes the kinetics in antibody levels after two doses of the bivalent human papillomavirus (HPV) vaccine in girls (birth cohort 2001) vaccinated in the routine Dutch vaccination program at 12 years of age, up to 7.5 years post-vaccination. Also, the antibody response one month post-vaccination of the first cohort of boys (birth cohort 2012, vaccinated at 10 years of age) eligible for HPV vaccination in the Netherlands is presented. Blood samples and questionnaire data were collected of girls and boys. HPV type-specific antibody concentrations (LU/mL) against HPV16/18/31/33/45/52/58 were assessed using a validated virus-like particle (VLP) multiplex immunoassay. For girls, antibody decays over time were modelled using the modified power-law decay model and the exponential decay model. The Geometric Mean Concentrations (GMCs) remained higher for HPV16/18 than for HPV types 31, 33, 45, 52, and 58 among girls up to 7.5 years post-vaccination. The antibody levels of HPV16 and HPV18 reached plateau values of 482 and 159 LU/mL, respectively. Mathematical modelling showed that the half-life values of HPV16/18 were 2.4- to 4.5-fold higher compared with the half-life values of the other HPV types. Among boys (aged 10 years), the GMC for HPV16 was significantly higher than among girls one month post-vaccination (aged 12 years). The GMCs of all HPV types declined over time, although the GMCs of HPV16/18 remained relatively high up to 7.5 years post-vaccination. The GMCs for HPV16/18 among boys were at least equally high as the GMCs among girls at one month post-vaccination. Further follow-up of the cohort of boys is needed to gain knowledge on long-term immune responses of young boys following bivalent HPV vaccination.

Invasive cervical cancer incidence following bivalent human papillomavirus vaccination: a population-based observational study of age at immunization, dose, and deprivation.

High-risk human papillomavirus causes cervical cancer. Vaccines have been developed that significantly reduce the incidence of preinvasive and invasive disease. This population-based observational study used linked screening, immunization, and cancer registry data from Scotland to assess the influence of age, number of doses, and deprivation on the incidence of invasive disease following administration of the bivalent vaccine. Data for women born between January 1, 1988, and June 5, 1996, were extracted from the Scottish cervical cancer screening system in July 2020 and linked to cancer registry, immunization, and deprivation data. Incidence of invasive cervical cancer per 100 000 person-years and vaccine effectiveness were correlated with vaccination status, age at vaccination, and deprivation; Kaplan Meier curves were calculated. No cases of invasive cancer were recorded in women immunized at 12 or 13 years of age irrespective of the number of doses. Women vaccinated at 14 to 22 years of age and given 3 doses of the bivalent vaccine showed a significant reduction in incidence compared with all unvaccinated women (3.2/100 000 [95% confidence interval (CI) = 2.1 to 4.6] vs 8.4 [95% CI = 7.2 to 9.6]). Unadjusted incidence was significantly higher in women from most deprived (Scottish Index of Multiple Deprivation 1) than least deprived (Scottish Index of Multiple Deprivation 5) areas (10.1/100 000 [95% CI = 7.8 to 12.8] vs 3.9 [95% CI = 2.6 to 5.7]). Women from the most deprived areas showed a significant reduction in incidence following 3 doses of vaccine (13.1/100 000 [95% CI = 9.95 to 16.9] vs 2.29 [95% CI = 0.62 to 5.86]). Our findings confirm that the bivalent vaccine prevents the development of invasive cervical cancer and that even 1 or 2 doses 1 month apart confer benefit if given at 12-13 years of age. At older ages, 3 doses are required for statistically significant vaccine effectiveness. Women from more deprived areas benefit more from vaccination than those from less deprived areas.

Cost-effectiveness analysis of single-dose or 2-dose of bivalent, quadrivalent, or nonavalent HPV vaccine in a low/middle-income country setting.

To compare the health impact and economic benefits among individuals who did not receive the human papillomavirus (HPV) vaccine to those who received a single dose, or 2 doses. The comparison was stratified by 4 types of vaccine in conjunction with primary HPV screening in a low/middle-income country setting. A Markov model was employed to simulate HPV infection and cervical cancer in a cohort of 100,000 12-year-old girls free of HPV. The study scrutinized 9 strategies: 1 dose and 2 doses of 2vHPV (Cervarix®), 2vHPV (Cecolin®), 4vHPV (Gardasil®), 9vHPV vaccine (Gardasil9®), and no vaccination. The primary outcome measure was the quality-adjusted life year (QALY) of each strategy. Incremental cost-effectiveness ratios were estimated over a lifetime horizon, accompanied by sensitivity analyses conducted. All vaccination programs yielded 41,298-71,057 QALYs gained accompanied by cost savings of 14,914,186-19,821,655 USD compared to no vaccination. Administering 2 doses of 9vHPV vaccine emerged as the most cost-effective strategy, boasting 406 USD/QALY, within a lower willingness to pay threshold. Sensitivity analysis demonstrated an 80% probability of the cost-effectiveness of the 2 doses of 9vHPV vaccine regimen. Furthermore, uncertainty around the costs of vaccination and vaccine efficacy exerted the most substantial influence on the cost-effectiveness findings. Oping for 2 doses of 9vHPV vaccine in conjunction with a primary HPV screening represents the most cost-effective option for implementing a school-based HPV vaccination program targeting 12-year-old girls in Thailand. Such findings provide valuable insights for policymakers in the realm of cervical cancer prevention.

Implementing the free HPV vaccination for adolescent girls aged below 14 in Shenzhen, Guangdong Province of China: experience, challenges, and lessons

Cervical cancer is a major public health concern in China, accounting for almost one-fifth of the global incidence and mortality. The recently prequalified domestic bivalent human papillomavirus (HPV) vaccine offers a practical and feasible preventive measure. In response to the global call for action, the National Health Commission issued an Action Plan to eliminate cervical cancer by 2030, with promotion of the HPV vaccination for school-aged girls as a critical step. Despite this, implementation of the vaccination has been patchy, with very low coverage among eligible girls. To address this, from December 2021 to December 2022, a demonstration project was launched in Shenzhen, Guangdong Province, to promote the inclusion of HPV vaccine in local immunisation programme and to address existing barriers to implementation. Using multiple sources of data, this article presents a case study of the demonstration project, analysing its impact on rolling out HPV vaccination among eligible girls and identifying any challenges encountered during implementation. The demonstration project has shown promising results in increasing the HPV vaccination rate, promoting public awareness and acceptance of the domestic HPV vaccine, and establishing a model for quickly scaling up the vaccination at the municipal level. The success of the project can be attributed to several factors, including strong governmental commitment, sufficient funding, multi-sectoral collaboration, ensured vaccine accessibility and affordability, improved vaccination services, and effective health education and communication strategies. Lessons learned from Shenzhen can provide valuable insights for future advocacy and implementation of the vaccination in other areas of China, but challenges must be addressed to achieve universal coverage. These include addressing vaccine hesitancy, expanding the programme to cover a broader age range, and ensuring consistent quality of vaccination services in primary care facilities. Overcoming these challenges will require innovative strategies, public-private partnerships, and sustained funding and resources. Future research should focus on evaluating the long-term effectiveness of the vaccination programme and identifying contextual factors that may impact its implementation in different settings. Overall, the effective control of cervical cancer in China will rely on the “political will” to ensure the incorporation of preventive interventions into policies and universal programme coverage.

Intralesional bivalent and quadrivalent human papillomavirus vaccines didn't significantly enhance the response of multiple anogenital warts when co-administered with intralesional Candida antigen immunotherapy. A randomized controlled trial.

Treatment of anogenital warts (AGWs) is challenging. Candida antigen immunotherapy has been proven to be a safe and relatively effective therapeutic modality; nevertheless, some patients may experience a partial or no response. Combining Candida antigen with other immunotherapies has been proposed to improve the cure rate. Immunotherapy with human papillomavirus (HPV) vaccines has been tried with conflicting outcomes. This study aimedto assess the efficacy and safety of intralesional Candida antigen, either alone or in combination with intralesional bivalent or quadrivalent HPV vaccines, for treating multiple AGWs. Eighty patients with multiple AGWs were included and randomly assigned to four equal groups: group A treated with intralesional Candida antigen only; group B treated with intralesional bivalent HPV vaccine (Cervarix) and Candida; group C treated with intralesional quadrivalent HPV vaccine (Gardasil) and Candida; and group D (control) treated with intralesional saline. Complete clearance of lesions was detected in 40%, 20%, and 60% of patients in Candida monotherapy, Cervarix/Candida, and Gardasil/Candida groups, respectively, whereas 40%, 60%, and 20% of patients in the three groups, respectively, showed partial response. Only 10% of the control group had a partial response. Therapeutic outcomes were significantly better in the three treatment groups compared to the control group, with no statistically significant difference between the Candida monotherapy group and the combination groups, but the response was significantly better in the Gardasil/Candida group than in the Cervarix/Candida group. No statistically significant difference was found between the studied groups regarding the development of side effects. Moreover, no recurrence was detected in any of the groups throughout the 3-month follow-up period. Based on our results,combining intralesional HPV vaccines with Candida antigen immunotherapy may haveno significant benefit for treating multiple AGWs. Candida antigen may be recommended as a relatively effective and inexpensive therapeutic modality. The combination of Gardasil and Candida was also effective but very expensive. The results of the Cervarix/Candida combination were unsatisfactory. This clinical trial was registered and approved prospectively by the ethical review board at Faculty of Medicine, Zagazig University.

An Updated Analysis of the Impact of HPV Vaccination Based on Long-term Effectiveness in the Netherlands.

Vaccination against human papillomavirus (HPV) is considered the most effective strategy to protect women from cervical cancer. Three HPV vaccines are currently licensed in Europe and, although they are generally supported by favorable health economic outcomes, current models fall short in predicting vaccination benefits. Here, we aim to re-evaluate the health benefits of HPV vaccination, using updated long-term effectiveness data and emphasizing quality of life losses related to pre-cancer disease and treatment. We used a static Markov model that compared "only screening" (includes unvaccinated girls) and "vaccination" (assumes 100% vaccination coverage with the bivalent HPV vaccine). A lifetime cohort of 100,000 uninfected 12-year-old girls was included, in which the number of cases with cervical intraepithelial neoplasia grade 2 or higher/3 (CIN2+, CIN3), cervical cancer, and cervical cancer deaths per scenario were determined. Furthermore, the reduction in major excisional procedures, the preterm deliveries averted, and the related gain in quality-adjusted life years (QALYs) due to vaccination were estimated. The bivalent vaccine showed larger reductions in CIN2+, CIN3, cervical cancer cases, cervical cancer deaths, and major excisional treatments, after including long-term efficacy and effectiveness data, compared to previous data. Moreover, we observed an increased amount of QALYs gained due to prevention of major excisional treatment and the negative side effects related to it. Updated health economic models for HPV vaccination, using updated and long-term effectiveness data and including prevention of treatment-related side effects, demonstrate a substantial additional positive effect on vaccination outcomes. Indeed, extrapolation of the bivalent HPV vaccine's updated long-term effectiveness data against HPV-related cervical diseases shows that the positive effects of vaccination may be more substantial than previously estimated. There is a graphical abstract available for this article.

Treatment response and tolerability of intralesional quadrivalent versus bivalent human papillomavirus vaccine for recalcitrant warts: A randomized controlled trial

Treatment response and tolerability of intralesional quadrivalent versus bivalent human papillomavirus vaccine for recalcitrant warts: A randomized controlled trial

Safety and immunogenicity of a pichia pastoris-expressed bivalent human papillomavirus (types 16 and 18) L1 virus-like particle vaccine in healthy Chinese women aged 9-45years: A randomized, double-blind, placebo-controlled phase 1 clinical trial.

We evaluated the safety and immunogenicity of high and low doses of a novel pichia pastoris-expressed bivalent (types 16 and 18) human papillomavirus (HPV) virus-like particle vaccine. In this randomized, double-blind, placebo-controlled phase 1 trial, we enrolled 160 healthy females aged 9-45years in Guangxi, China who were randomized (1:1:2) to receive either low (0.5mL) or high (1.0mL) dosages of bivalent HPV vaccine, or placebo (aluminum adjuvant) in a 0, 2, 6months schedule. Adverse events and other significant conditions that occurred within 30days after each vaccination were recorded throughout the trial. Sera were collected at days 0, 60, 180 and 210 to measure anti-HPV 16/18 neutralizing antibodies. A total of 160 participants received at least one dose of the HPV vaccine and 152 completed the three dose vaccination series. Reporting rates of adverse events in placebo, low dose (0.5mL) and high dose (1.0mL) groups were 47.5%, 55.0% and 55.0%, respectively. No serious adverse events occurred during this trial. 100% of the participants who received three doses of the HPV vaccine produced neutralizing antibodies against HPV 16/18 vaccine. For HPV 16 and HPV 18, the geometric mean titers (GMTs) were similar between the low dose group (GMTHPV 16=10816 [95% CI: 7824-14953]), GMTHPV 18=3966 [95% CI: 2693-5841]) and high dose group (GMT HPV 16=14482 [95% CI: 10848-19333], GMT HPV 18=3428 [95% CI: 2533-4639]). The pichia pastoris-expressed bivalent HPV vaccine was safe and immunogenic in Chinese females aged 9-45years. The low dosage (0.5mL) was selected for further immunogenicity and efficacy study.

Effects of two and three vaccinations with the bivalent HPV vaccine on the prevalence and load of HPV in clearing and persistent infections in young women.

Human papillomavirus viral load (HPV VL) is associated with persistence, which increases cervical cancer risk. The bivalent vaccine protects against oncogenic HPV16/18 and cross-protects against several non-vaccine types. We examined the effect of two-dose (2D) and three-dose (3D) vaccination on HPV prevalence and viral load in clearing (CIs) and persistent infections (PIs), 6y and 12y post-vaccination, respectively. Vaginal swabs collected from HPV Among Vaccinated And Non-vaccinated Adolescents (HAVANA, 3D-eligible) and HAVANA-2 (2D-eligble) participants were genotyped for HPV with the SPF10-DEIA-LiPA25. HPV VL was measured with type-specific qPCRs. HPV16, 18, 31, 33 and 45 CI and/or PI prevalence and HPV16, 18, and 31 VLs in CIs were significantly reduced in 3D vaccinated women compared to unvaccinated women. Except for HPV11 and HPV59 CIs, no significant VL differences were observed among vaccinated women, ≤6y and >6y post-vaccination. Infection numbers were low in 2D-eligible women, with no HPV16 and 18 in vaccinated women. No VL differences for the remaining types were found. 3D vaccination reduces HPV prevalence in CIs and PIs and decreases HPV VLs in CIs, 12y post-vaccination for vaccine and several non-vaccine types. 2D-eligible women had low infection numbers, with no HPV16/18 among vaccinated women.

Early effect of bivalent human papillomavirus vaccination on cytology outcomes in cervical samples among young women in the Netherlands.

The first HPV-vaccine eligible cohorts in the Netherlands will enter the cervical screening program in 2023. However, a substantial number of young women already have had a cervical sample taken before entry into the regular screening program. This study was initiated to explore early effects of HPV vaccination on detection of cytological abnormalities in cervical samples of women younger than the screening age. Results of cervical samples were obtained from the Dutch National Pathology Databank (PALGA) and were linked to the women's HPV vaccination status from the national vaccination registry (Praeventis) (N= 42,171). Occurrence of low-grade and high-grade squamous intraepithelial lesions or worse (LSIL and HSIL+) and high-risk HPV positive tests (hrHPV) in the first cervical sample were compared between vaccinated and unvaccinated women by multivariable logistic regression analysis, corrected for age at cervical sampling and age of vaccination (12/13 years, ≥=14 years). For fully vaccinated women (three- or two-dose schedule), statistically significant reductions were seen for all outcomes compared to unvaccinated women (hrHPV: adjusted OR, 0.70, 95% CI, 0.63-0.79; LSIL: 0.70, 0.61-0.80; HSIL+: 0.39, 0.30-0.51). By linking nation-wide registries on pathology and vaccination, we show significant beneficial early effects of HPV-vaccination on LSIL, HSIL+, CIN3/AIS/carcinoma and hrHPV detection in young women upto 24 years of age who have a cervical sample taken before entry into the cervical cancer screening program.

Comparative Effects of Bivalent, Quadrivalent, and Nonavalent Human Papillomavirus Vaccines in The Prevention of Genotype-Specific Infection: A Systematic Review and Network Meta-Analysis.

Human papillomavirus (HPV) infection is a major global disease burden and the main cause of cervical cancer. Certain HPV genotypes, with are the most common etiologic pathogens and cause a significant disease burden, are being targeted for vaccine development. However, few studies have focused on the comparative effectiveness of the bivalent HPV (2v-HPV), quadrivalent HPV (4v-HPV), and nonavalent HPV (9v-HPV) vaccines against HPV strain-specific infection. This study investigated the comparative effects of these vaccines against genotype-specific infection. We conducted a pairwise and network meta-analysis of published randomized clinical trials of HPV vaccines according to sex and HPV infection status for nine HPV genotypes (HPV 6/11/16/18/31/33/45/52/58). Overall, 10 randomized controlled trials (12 articles) were included in this study. In the network meta-analysis, no statistically significant differences were observed in the prevention of carcinogenic HPV strains (16/18/31/33/45/52/58) between the 2v-HPV and 4v-HPV vaccines in female HPV infection-naïve populations. However, the 9v-HPV vaccine showed a significantly superior effect compared with 2v-HPV and 4v-HPV vaccines in preventing HPV 31/33/45/52/58 infections. Although 2v-HPV and 4v-HPV vaccines provided some cross-protection against HPV 31/33/45/52/58 infections, the effect was significant only on HPV 31 infection. For HPV 16 and 18, neither statistically significant nor small differences were found in the prevention of HPV infection among the 2v-HPV, 4v-HPV, and 9v-HPV vaccines. Our study complements previous understanding of how the effect of HPV vaccines differs according to the HPV genotype. This is important because HPV genotype prevalence varies among countries. We advocate for continued efforts in vaccinating against HPV, while public health agencies should consider the difference in the vaccine effect and HPV genotype prevalence when implementing HPV vaccination in public vaccination programs.

The effects of bivalent human papillomavirus (HPV) vaccination on high-risk anogenital HPV infection among sexually active female adolescents with and without perinatally acquired HIV.

Females with perinatal HIV (PHIV) infection are at elevated risk for anogenital high-risk human papillomavirus (HR-HPV) infection. Limited data are available around the effect of the HPV vaccination after initiation of sexual activity among PHIV youth. This study aims to assess the impact of a bivalent HPV vaccination on the persistence of anogenital HR-HPV among sexually active female PHIV youth and matched HIV-negative controls aged 12-24years in Thailand and Vietnam. During a 3-year study, prevalent, incident, and persistent HR-HPV infection were assessed at annual visits. A subset of participants received a bivalent HPV vaccine. Samples were taken for HPV testing from the vagina, cervix, and anus. HR-HPV persistence was defined as the detection of the same genotype(s) at any anogenital compartment over≥two consecutive visits. Of the 93 PHIV and 99 HIV-negative female youth enrolled in this study, 25 (27%) PHIV and 22 (22%) HIV-negative youth received a HPV vaccine. Persistent infection with any HR-HPV type was significantly lower among PHIV youth who received the vaccine compared to those who did not (33%vs 61%, P =0.02); a difference was not observed among HIV-negative youth (35%vs 50%, P =0.82). PHIV infection (adjusted prevalence ratio [aPR] 2.31, 95% CI 1.45-3.67) and not receiving a HPV vaccine (aPR, 1.19, 95%CI 1.06-1.33) were associated with persistent anogenital HR-HPV infection. Bivalent HPV vaccination after initiation of sexual activity was associated with reduced persistence of anogenital HR-HPV infection in Southeast Asian PHIV female youth, which may be related to vaccine cross-protection. Primary and catch-up HPV vaccinations should be prioritised for children and youth with HIV.

The Clinical and Economic Impact of a Nonavalent Versus Bivalent Human Papillomavirus National Vaccination Program in Taiwan

This study aimed to estimate the epidemiologic and economic impact of a nonavalent human papillomavirus (HPV) vaccination program for 13- to 14-year-old females compared with that of the bivalent vaccine in Taiwan. A previously developed dynamic transmission model for the nonavalent HPV vaccine was adapted to the Taiwan setting. The natural history of cervical cancer and genital warts was simulated by the HPV model assuming an 80% vaccination coverage rate in girls aged 13 to 14 years of age with a 2-dose schedule for the nonavalent and bivalent HPV vaccines. A lifetime duration of vaccine protection was assumed for the HPV vaccine types. The model estimated that the nonavalent HPV vaccine would prevent an additional 15 951 cervical cancer cases, 6600 cervical cancer-related deaths, 176 702 grade 2 or grade 3 cervical intraepithelial neoplasia cases, 103 959 grade 1 cervical intraepithelial neoplasia cases, and 1 115 317 genital warts cases compared with the bivalent HPV vaccine. The nonavalent HPV vaccination program was projected to cost an additional New Taiwan dollars (NTD) 675.21 per person and to produce an additional 0.00271 quality-adjusted life-year per person over 100 years compared with the bivalent HPV vaccine. Thus, the incremental cost-effectiveness ratio of the nonavalent HPV vaccine versus the bivalent HPV vaccine was NTD 249 462/quality-adjusted life-year. A nonavalent HPV vaccination program for 13- to 14-year-old girls would have additional public health and economic impacts and would be highly cost-effective compared with the bivalent HPV vaccine, relative to per capita gross domestic product, which is estimated at NTD 746 526 for Taiwan.

Precancerous cervical lesions caused by non-vaccine-preventable HPV types after vaccination with the bivalent AS04-adjuvanted HPV vaccine: an analysis of the long-term follow-up study from the randomised Costa Rica HPV Vaccine Trial.

In women vaccinated against human papillomavirus (HPV), reductions in cervical disease and related procedures results in more women having intact transformation zones, potentially increasing the risk of cervical lesions caused by non-vaccine-preventable HPV types, a phenomenon termed clinical unmasking. We aimed to evaluate HPV vaccine efficacy against cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and cervical intraepithelial neoplasia grade 3 or worse (CIN3+) attributed to non-preventable HPV types in the long-term follow-up phase of the Costa Rica HPV Vaccine Trial (CVT). CVT was a randomised, double-blind, community-based trial done in Costa Rica. Eligible participants were women aged 18-25 years who were in general good health. Participants were randomly assigned (1:1) to receive an HPV 16 and 18 AS04-adjuvanted vaccine or control hepatitis A vaccine, using a blocked randomisation method (permuted block sizes of 14, 16, and 18). Vaccines in both groups were administered intramuscularly with 0·5 mL doses at 0, 1, and 6 months. Masking of vaccine allocation was maintained throughout the 4-year randomised trial phase, after which participants in the hepatitis A virus vaccine control group were provided the HPV vaccine and exited the study; a screening-only, unvaccinated control group was enrolled. The unvaccinated control group and HPV vaccine group were followed up for 7 years, during which treatment allocation was not masked. One of the prespecified primary endpoints for the long-term follow-up phase was precancers associated with HPV types not prevented by the vaccine, defined as histologically confirmed incident CIN2+ events or CIN3+ events attributed to any HPV type except HPV 16, 18, 31, 33, and 45. Our primary analytical period was years 7-11. Primary analyses were in all participants with at least one follow-up visit and excluded participants with a previous endpoint (ie, modified intention-to-treat cohort). Safety endpoints have been reported elsewhere. This trial is registered with ClinicalTrials.gov, NCT00128661 and NCT00867464. The randomised, masked trial phase is completed; an unmasked subset of women in the HPV-vaccinated group is under active investigation. Between June 28, 2004, and Dec 21, 2005, 7466 participants were enrolled (HPV vaccine group n=3727 and hepatitis A virus vaccine control group n=3739). Between March 30, 2009, and July 5, 2012, 2836 women enrolled in the new unvaccinated control group. The primary analytical cohort (years 7 to 11) included 2767 participants in the HPV vaccine group and 2563 in the unvaccinated group for the CIN2+ events endpoint assessment and 2826 participants in the HPV vaccine group and 2592 in the unvaccinated control group for the CIN3+ events endpoint assessment. Median follow-up during years 7 to 11 for women included for the CIN2+ events analysis was 52·8 months (IQR 44·0 to 60·7) for the HPV vaccine group and 49·8 months (42·0 to 56·9) for the unvaccinated control group. During years 7 to 11, clinical unmasking was observed with a negative vaccine efficacy against CIN2+ events attributed to non-preventable HPV types (-71·2% [95% CI -164·0 to -12·5]), with 9·2 (95% CI 2·1 to 15·6) additional CIN2+ events attributed to non-preventable HPV types per 1000 HPV-vaccinated participants versus HPV-unvaccinated participants. 27·0 (95% CI 14·2 to 39·9) fewer CIN2+ events irrespective of HPV type per 1000 vaccinated participants were observed during 11 years of follow-up. Vaccine efficacy against CIN3+ events attributed to non-preventable HPV types during years 7 to 11 was -135·0% (95% CI -329·8 to -33·5), with 8·3 (3·0 to 12·8) additional CIN3+ events attributed to non-preventable HPV types per 1000 vaccinated participants versus unvaccinated participants. Higher rates of CIN2+ events and CIN3+ events due to non-preventable HPV types in vaccinated versus unvaccinated participants suggests clinical unmasking could attenuate long-term reductions in high-grade disease following successful implementation of HPV vaccination programmes in screened populations. Importantly, the net benefit of vaccination remains considerable; therefore, HPV vaccination should still be prioritised as primary prevention for cervical cancer. National Cancer Institute and National Institutes of Health Office of Research on Women's Health. For the Spanish translation of the abstract see Supplementary Materials section.

Head-to-Head Comparison of Bi- and Nonavalent Human Papillomavirus Vaccine-Induced Antibody Responses.

For head-to-head comparison of human papillomavirus (HPV) antibody levels induced by different vaccines, 25-year-old vaccine-naive women were given either the bivalent (n = 188) or the nonavalent HPV vaccine (n = 184). Six months after vaccination antibodies against pseudovirions from 17 different HPV types (HPV6/11/16/18/31/33/35/39/45/51/52/56/58/59/66/68/73) were measured. Antibodies against HPV16/18 were higher after bivalent HPV vaccination (mean international units [IU] 1140.1 and 170.5 for HPV16 and 18, respectively) than after nonavalent vaccination (265.1 and 22.3 IUs, respectively). The bivalent vaccine commonly induced antibodies against the nonvaccine HPV types 31/33/35/45 or 58. The nonavalent vaccine induced higher antibodies against HPV6/11/31/33/45/52/58 and 35.

A community intervention effectiveness study of single dose or two doses of bivalent HPV vaccine (CERVARIX®) in female school students in Thailand.

Human papillomavirus (HPV) is a common infection principally spread through sexual activity. Most HPV infections are asymptomatic and resolve spontaneously. However, persistent infection may progress to cervical cancer. Highly efficacious HPV vaccines have been available since 2006, yet uptake into national programs has been slow in part due to cost. WHO guidelines call for a two-dose (0,6 month) schedule for girls 9-14 years of age. Post-hoc analyses of randomized trials have found high vaccine effectiveness following a single dose of vaccine. In order to provide additional data on the potential impact of single dose HPV vaccination in a real-world setting, we are conducting an effectiveness study among Thai schoolgirls. This is an observational study of a single dose (SD) or two doses (2D) of the bivalent HPV vaccine CERVARIX® (GlaxoSmithKline plc.) administered in a school-based program to 8-9,000 Grade 8 female students in two provinces of Thailand beginning in 2018; one province is assigned the SD, and the other the standard 2D regimen. The reduction in HPV vaccine-type prevalence will be assessed in each province two and four years after vaccination by comparing HPV prevalence in urine samples obtained through cross-sectional surveys of the immunized grade cohort as they age and compared to a historical "baseline" HPV prevalence of same age students.

Efficacy of Single-Dose Human Papillomavirus Vaccination among Young African Women

BackgroundSingle-dose human papillomavirus (HPV) vaccination, if efficacious, would be tremendously advantageous, simplifying implementation and decreasing costs.MethodsWe performed a randomized, multicenter, double-blind, controlled trial of single-dose nonavalent (HPV 16/18/31/33/45/52/58/6/11 infection) or bivalent (HPV 16/18 infection) HPV vaccination compared with meningococcal vaccination among Kenyan women 15 to 20 years of age. Enrollment and 6-monthly cervical swabs and a month 3 vaginal swab were tested for HPV deoxyribonucleic acid (DNA). Enrollment sera were tested for HPV antibodies. The modified intent-to-treat (mITT) cohort comprised participants who had an HPV antibody-negative result at enrollment and an HPV DNA-negative result at enrollment and month 3. The primary outcome was incident persistent vaccine-type HPV infection by month 18.ResultsBetween December 2018 and June 2021, 2275 women were randomly assigned and followed. A total of 758 participants received the nonavalent HPV vaccine, 760 received the bivalent HPV vaccine, and 757 received the meningococcal vaccine; retention was 98%. Thirty-eight incident persistent infections were detected in the HPV 16/18 mITT cohort: one each among participants assigned to the bivalent and nonavalent groups and 36 among those assigned to the meningococcal group. Nonavalent vaccine efficacy (VE) was 97.5% (95% confidence interval [CI], 81.7 to 99.7%; P≤0.0001), and bivalent VE was 97.5% (95% CI, 81.6 to 99.7%; P≤0.0001). Thirty-three incident persistent infections were detected in the HPV 16/18/31/33/45/52/58 mITT cohort: four in the nonavalent group and 29 in the meningococcal group. Nonavalent VE for HPV 16/18/31/33/45/52/58 was 88.9% (95% CI, 68.5 to 96.1; P<0.0001). The rate of serious adverse events was 4.5% to 5.2% by group.ConclusionsOver the 18-month timeframe we studied, single-dose bivalent and nonavalent HPV vaccines were each highly effective in preventing incident persistent oncogenic HPV infection, similar to multidose regimens. (Funded by the National Institutes of Health, the Bill and Melinda Gates Foundation, and the University of Washington; ClinicalTrials.gov number, NCT03675256.)

The impact of catch-up bivalent human papillomavirus vaccination on cervical screening outcomes: an observational study from the English HPV primary screening pilot

BackgroundIn England, bivalent vaccination (Cervarix) against high-risk human papillomavirus (HR-HPV) genotypes 16/18 was offered in a population-based catch-up campaign in 2008–2010 to girls aged 14–17 years. These women are now entering the national cervical screening programme. We determined the impact of catch-up bivalent vaccination on their screening outcomes.MethodsWe studied the overall and genotype-specific screening outcomes in 108,138 women aged 24–25 (offered vaccination) and 26–29 years (not offered vaccination) included in the English HPV screening pilot between 2013 and 2018.ResultsAt 24–25 years, the detection of high-grade cervical intraepithelial neoplasia (CIN2+) associated with HPV16/18 decreased from 3 to 1% (p < 0.001), with estimated vaccine effectiveness of 87% (95% CI: 82–91%). The detection of any CIN2+ halved from 6 to 3% (p < 0.001), with an estimated vaccine effectiveness of 72% (95% CI: 66–77%). The positive predictive value of a colposcopy for CIN2+ decreased for both low-grade (p < 0.001) and high-grade (p = 0.02) abnormalities on triage cytology. The decreases in screen-detected abnormalities at age 26-29 were of a substantially smaller magnitude.ConclusionsThese data confirm high effectiveness of bivalent HPV vaccination delivered through a population-based catch-up campaign in England. These findings add to the rationale for extending screening intervals for vaccinated cohorts.

Cost-Effectiveness of Bivalent, Quadrivalent, and Nonavalent HPV Vaccination in South Africa.

Background and ObjectivesIn South Africa, the prevalence of human papillomavirus (HPV) and associated diseases, such as cervical cancer and genital warts, is among the highest in the world. This study evaluates the cost-effectiveness of bivalent, quadrivalent, and nonavalent HPV vaccination for 9- to 14-year-old girls from the South African healthcare system perspective.MethodsA Markov model portraying the natural HPV disease progression from high-risk infection to cervical intraepithelial neoplasia (CIN) I, CIN II/III, or cervical cancer and from low-risk infection to genital warts was built. Transition probability, utility, and efficacy data were sourced from peer-reviewed literature. Vaccination costs were calculated based on the World Health Organization (WHO) guidelines. The model was populated with a cohort of 520,000 9-year-old girls to calculate incremental cost-effectiveness ratios (ICER) in South African Rand (R) per quality-adjusted life-years (QALYs) gained for each vaccination strategy.ResultsAll HPV vaccination strategies dominate the no vaccine strategy. Compared with the bivalent vaccine, the nonavalent strategy increases QALYs by 0.14 and costs by R1793 (ICER: R13,013 per QALY) per person, while the quadrivalent vaccination provides −0.02 incremental QALYs and R1748 costs (ICER: −R116,397 per QALY). Consequently, at the South African willingness-to-pay threshold of R23,630 per QALY, nonavalent vaccination is the preferred strategy, with a probability of 90.2%. Scenario analysis demonstrated that results are influenced by vaccine coverage, efficacy, and duration of efficacy.ConclusionsThe introduction of nonavalent for bivalent HPV vaccination is a cost-effective intervention in South Africa. HPV vaccination should be part of a multifaceted public health strategy entailing screening, condoms, and education of all stakeholders to reduce the significant burden of sexual transmitted diseases in South Africa. Sex-neutral and catch-up vaccinations are subjects for further research.Graphical Supplementary InformationThe online version contains supplementary material available at 10.1007/s40261-022-01138-6.