Precision and correlation of ED50 and endpoint titer method in measuring HPV vaccine immunogenicity.

Cervical cancer, the second leading cause of cancer-related deaths among women, is caused by human papillomavirus (HPV), a sexually transmitted virus. Vaccination is an effective preventive measure against viral infections and subsequent development of cervical cancer. Enzyme-linked immunosorbent assay (ELISA) is commonly used to measure specific binding antibody titers and assess the immunogenicity of test vaccines in preclinical models or clinical volunteers. Two methods of deriving titers, the endpoint titer (ET) and the effective dilution producing a median maximal effective fold of dilution (ED50) with a cut-off value, are widely used. For HPV, a pseudovirion-based neutralization assay (PBNA) is used to measure functional antibody titers. The ELISA binding titers and functional PBNA titers were found to be well-correlated for all nine HPV types tested in the vaccine, consistent with previous studies on HPV 16/18. Comparing the PBNA results with the two titration methods, the ED50 method showed higher precision and a closer correlation with PBNA results, both for individual types and pooled data analysis for all nine types. When comparing the titration results of the ET method based on a cut-off value with the ED50 method using all the data points across the dilution series, the ED50 method demonstrated better precision and a stronger correlation with PBNA results.

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

BACKGROUND: The nine-valent human papillomavirus (9vHPV) vaccine protects against infection and disease related to HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. The pivotal 36-month Phase III immunogenicity study of 9vHPV vaccine in 9- to 15-year-old girls and boys was extended to assess long-term immunogenicity and effectiveness through approximately 10 years after vaccination. We describe results of an interim analysis based on approximately 8 years of follow-up after vaccination. METHODS: Participants aged 9-15 years who received three doses of 9vHPV vaccine (at day 1, month 2, and month 6) in the base study and consented to follow-up were enrolled in the long-term follow-up study extension (N = 1272 [females, n = 971; males, n = 301]). Serum was collected at months 66 and 90 to assess antibody responses. For effectiveness analysis, genital swabs were collected (to assess HPV DNA by polymerase chain reaction [PCR]) and external genital examination was conducted (to detect external genital lesions) every 6 months starting when the participant reached 16 years of age. Cervical cytology tests were conducted annually when female participants reached 21 years of age; participants with cytological abnormalities were triaged to colposcopy based on a protocol-specified algorithm. External genital and cervical biopsies of abnormal lesions were performed, and histological diagnoses were adjudicated by a pathology panel. Specimens were tested by PCR to detect HPV DNA. RESULTS: Geometric mean titers for each 9vHPV vaccine HPV type peaked around month 7 and gradually decreased through month 90. Seropositivity rates remained >90% through month 90 for each of the 9vHPV vaccine types by HPV immunoglobulin Luminex Immunoassay. No cases of HPV6/11/16/18/31/33/45/52/58-related high-grade intraepithelial neoplasia or genital warts were observed in the per-protocol population (n = 1107) based on a maximum follow-up of 8.2 years (median 7.6 years) post-Dose 3. Incidence rates of HPV6/11/16/18/31/33/45/52/58-related 6-month persistent infection in females and males were 49.2 and 37.3 per 10,000 person-years, respectively, which were within ranges expected in vaccinated cohorts. There were no vaccine-related SAEs or deaths during the period covered by this interim analysis. CONCLUSIONS: The 9vHPV vaccine provided sustained immunogenicity and durable effectiveness through approximately 7 and 8 years, respectively, following vaccination of girls and boys aged 9-15 years.

Prevalence of high-risk human papillomavirus after HPV-vaccination in Denmark.

Vaccination against human papillomavirus (HPV) has been introduced as a public health initiative in many countries, including Denmark since October 2008. It is important to monitor postimplementation effectiveness of HPV-vaccination at the population-level. We studied HPV-prevalence after first invitation to screening at age 23 years in women offered the quadrivalent HPV-vaccine at the age of 14 years. Randomly selected screening samples from women born in 1994 in four out of five Danish regions were subjected to analysis for HPV in addition to routine cytology. Cobas4800 was used in all participating pathology departments. Data from a Danish prevaccination cross-sectional study using Hybrid Capture 2, and a Danish split-sample study using Cobas4800 were used for comparison. In the period from February 2017 to April 2019, 6233 screening samples from women born in 1994 were selected for HPV-analysis; 27 samples had no HPV-test and 3 samples had no HPV-diagnosis, leaving 6203 samples with an HPV-diagnosis. Prevalence of any high-risk (HR) HPV was 35%; only 0.9% were positive for vaccine HPV types 16/18 while the remaining 34% were positive for other HR HPV. When comparing with prevaccination prevalence data, HPV-16/18 decreased by 95%; RR = 0.05 (95% CI 0.04-0.06), while other HR HPV remained fairly constant; RR = 0.88 (95% CI 0.82-0.94) and RR = 0.95 (95% CI 0.88-1.03), respectively. One-third of women vaccinated as girls with the quadrivalent HPV-vaccine were HR HPV-positive at time of first invitation to screening. Vaccine HPV-types 16 and 18 were almost eliminated, while the prevalence of nonvaccine HR HPV-types remained constant.

Epidemiology and prevention of Human Papillomavirus.

Human papillomavirus is the most common sexually transmitted infection, and skin-to-skin genital contact is sufficient for virus transmission. Cervical cancer is the second-most common cancer in women living in less developed regions, with an estimated 445,000 new cases in 2012 and 230,000 deaths every year. Until now, more than 200 types of HPV have been identified, and about 15 types (HPV-16, -18, -31, -33, -35, -39, -45, -51, -52, -56, -58, -59, -66, -68, -82) have been shown to cause cervical cancer because they are able to transform infected cells into malignant tumor cells. The bivalent vaccine containing the serotypes 16 and 18 and the quadrivalent vaccine containing the serotypes 16, 18, 6 and 11, have been used in Italy for many years. The European Medicines Agency authorized marketing of the Gardasil 9 vaccine in the European Union on June 2015. Today, Public Health targets the immunization of adolescents of both genders based on new and important scientific evidence for maximum protection from all HPV related pathologies directly preventable with vaccination.

Clinical and economic impact of school-based nonavalent human papillomavirus vaccine on women in Singapore: a transmission dynamic mathematical model analysis.

OBJECTIVE: To examine the epidemiological and economic impact of a nine-valent (nonavalent) human papillomavirus (HPV) 6/11/16/18/31/33/45/52/58 vaccine programme for young teenagers in Singapore. DESIGN: Mathematical modelling. SETTING: Pharmaco-economic simulation projection. POPULATION: Singapore demography. METHODS: Clinical, epidemiological and financial data from Singapore were used in a validated HPV transmission dynamic mathematical model to analyse the impact of nonavalent HPV vaccination over quadrivalent and bivalent vaccines in a school-based 2-dose vaccination for 11- to 12-year-old girls in the country. The model assumed routine cytology screening in the current rate (50%) and vaccine coverage rate of 80%. MAIN OUTCOME MEASURES: Changes over a 100-year time period in the incidence and mortality rates of cervical cancer, case load of genital warts, and incremental cost-effectiveness ratio (ICER). RESULTS: Compared with bivalent and quadrivalent HPV vaccination programmes, nonavalent HPV universal vaccination resulted in an additional reduction of HPV31/33/45/52/58 related CIN1 of 40.5%, CIN 2/3 of 35.4%, cervical cancer of 23.5%, and cervical cancer mortality of 20.2%. Compared with bivalent HPV vaccination, there was an additional reduction in HPV-6/11 related CIN1 of 75.7%, and genital warts of 78.9% in women and 73.4% in men. Over the 100 years, after applying a discount of 3%, disease management cost will be reduced by 32.5% (versus bivalent) and 7.5% (versus quadrivalent). The incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year gained was SGD 929 compared with bivalent vaccination and SGD 9864 compared with quadrivalent vaccination. CONCLUSION: Universal two-dose nonavalent HPV vaccination for 11- to 12-year-old adolescent women is very cost-effective in Singapore. TWEETABLE ABSTRACT: Nonavalent HPV vaccination of 11- to 12-year-old girls is cost-effective in Singapore.

Overview of the benefits and potential issues of the nonavalent HPV vaccine.

HPV-related diseases affect anogenital and oropharyngeal regions, heavily affecting the psychosexual dimension of both male and female individuals. HPV vaccination programs based on a bivalent or quadrivalent vaccine have opened broad perspectives for primary prevention. A nonavalent HPV vaccine (9vHPV), covering nine genotypes (HPV6, HPV11, HPV16, HPV18, HPV31, HPV33, HPV45, HPV52, and HPV58), might provide further improvement in terms of direct protection. In the present report, efficacy and safety data from 9vHPV vaccine development programs are examined. Efficacy data come from a pivotal trial, which was conducted among women aged 16-26 years randomly assigned to receive either the 9vHPV or the quadrivalent HPV (4vHPV) vaccine. The 9vHPV vaccine was shown to have potential benefits as compared with 4vHPV, increasing the overall estimated rate of prevention to 90% for cervical cancer and up to 80% for precancerous cervical lesions. For all other HPV-related pre-invasive and invasive lesions, 9vHPV showed potentially greater disease reduction, depending on the anatomic region examined. Thus, the 9vHPV vaccine shows clinical potential for the prevention of HPV-related diseases in both sexes. Future adoption of 9vHPV will depend on factors including market price, cost-effectiveness data, use of a two-dose schedule, and safety and efficacy monitoring in real-life programs.

Immunogenicity of next-generation HPV vaccines in non-human primates: Measles-vectored HPV vaccine versus Pichia pastoris recombinant protein vaccine.

Human papillomavirus (HPV) infection is the most common sexually transmitted disease worldwide. HPVs are oncogenic small double-stranded DNA viruses that are the primary causal agent of cervical cancer and other types of cancers, including in the anus, oropharynx, vagina, vulva, and penis. Prophylactic vaccination against HPV is an attractive strategy for preventing cervical cancer and some other types of cancers. However, there are few safe and effective vaccines against HPV infections. Current first-generation commercial HPV vaccines are expensive to produce and deliver. The goal of this study was to develop an alternate potent HPV recombinant L1-based vaccines by producing HPV virus-like particles into a vaccine that is currently used worldwide. Live attenuated measles virus (MV) vaccines have a well-established safety and efficacy record, and recombinant MV (rMV) produced by reverse genetics may be useful for generating candidate HPV vaccines to meet the needs of the developing world. We studied in non-human primate rMV-vectored HPV vaccine in parallel with a classical alum adjuvant recombinant HPV16L1 and 18L1 protein vaccine produced in Pichia pastoris. A combined prime-boost approach using both vaccines was evaluated, as well as immune interference due to pre-existing immunity against the MV. The humoral immune response induced by the MV, Pichia-expressed vaccine, and their combination as priming and boosting approaches was found to elicit HPV16L1 and 18L1 specific total IgG and neutralizing antibody titres. Pre-existing antibodies against measles did not prevent the immune response against HPV16L1 and 18L1.

Eurogin Roadmap 2015: How has HPV knowledge changed our practice: Vaccines.

This review is one of two complementary reviews that have been prepared in the framework of the Eurogin Roadmap 2015 to evaluate how knowledge about HPV is changing practices in HPV infection and disease control through vaccination and screening. In this review of HPV vaccine knowledge, we present the most significant findings of the past year which have contributed to our knowledge of the two HPV prophylactic vaccines currently in widespread use and about the recently licensed nonavalent HPV vaccine. Whereas anal cancer is dealt with in the companion mini-review on screening, we also review here the rapidly evolving evidence regarding HPV-associated head and neck cancer and priority research areas.

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

BACKGROUND: When the bivalent and the quadrivalent HPV vaccines were marketed they were presented as having comparable efficacy against cervical cancer. Differences between the vaccines are HPV types included and formulation of the adjuvant. METHOD: A systematic review was conducted to assess the efficacy of the two vaccines against cervical cancer. Outcomes considered were CIN2+, CIN3+, and AIS. RESULTS: Nine reports (38,419 women) were included. At enrollment mean age of women was 20 years, 90% had negative cytology, and 80% were seronegative and/or DNA negative for HPV 16 or 18 (naïve women). In the TVC-naïve, VE against CIN2+ was 58% (95% CI: 35, 72); heterogeneity was detected, VE being 65% (95% CI: 54, 74) for the bivalent and 43% (95% CI: 23, 57) for the quadrivalent. VE against CIN3+ was 78% (95% CI: <0, 97); heterogeneity was substantial, VE being 93% (95% CI: 77, 98) for the bivalent and 43% (95% CI: 12, 63) for the quadrivalent. VE in the TVC was much lower. No sufficient data were available on AIS. CONCLUSIONS: In naïve girls bivalent vaccine shows higher efficacy, even if the number of events detected is low. In women already infected the benefit of the vaccination seems negligible.

Vacinação contra papilomavírus humano / Vaccination against human papillomavirus

A infecção pelo papilomavírus humano é comum e produz manifestações diversas. Essa infecção adquire importância para saúde pública, pois tem sido associada a malignidades do trato genital em homens e mulheres. Atualmente, temos disponíveis duas vacinas para prevenção da infecção pelo papilomavírus humano e, consequentemente, de doenças a ele associadas.

Human papillomavirus infection is common and causes different manifestations. This infection is a public health concern because it has been associated with genital tract malignant diseases among men and women. Currently two vaccines are available to prevent the human papillomavirus infection and its associated diseases.

Papillomavirus vaccine coverage and its determinants in South-Eastern France.

OBJECTIVES: We wanted: (i) to assess vaccine coverage (VC) for papillomavirus (HPV) (one and three doses of the vaccine, VC1 and VC3) and compliance with the recommended vaccination regimen (3rd dose within 1 year after the 1st dose) among 14-16 year-old girls; and (ii) to identify the factors independently associated with VC and compliance with the recommended vaccination regimen. METHODS: We conducted a descriptive longitudinal study, using the National Health Insurance reimbursement database, for years 2007 to 2009, in South-Eastern France. We performed a multivariate analysis (Cox proportional hazards model). RESULTS: VC1 was 35.5%, with 68.8% of those who started vaccination having completed the 3-dose regimen, 64.1% within one year. VC1 and VC3 were positively associated with the girl's age. Girls covered by the complementary social welfare healthcare program and those living in rural areas had lower VC1 and VC3. Being covered by the complementary social welfare healthcare program was also associated with lower compliance with the recommended vaccination regimen. VC1 and VC3 were positively associated with the number of medical consultations during the study period. Important geographical variations were noted regarding VC1. CONCLUSIONS: Our study confirms that VC for HPV is insufficient in our region, and that there are socio-economic and geographical inequalities. Even though the vaccine is reimbursed for all girls, efforts must be made to improve VC, particularly for girls covered by the complementary social welfare healthcare program and those living in rural areas.

Vaccination against human papillomavirus.

Human papillomavirus infection is common and causes different manifestations. This infection is a public health concern because it has been associated with genital tract malignant diseases among men and women. Currently two vaccines are available to prevent the human papillomavirus infection and its associated diseases.

Impact of vaccine protection against multiple HPV types on the cost-effectiveness of cervical screening.

Cross-protection against non-HPV16/18 types and the emergence of broad spectrum vaccines protecting against multiple HPV types will influence the cost-effectiveness of future screening. To assess this influence we used an individual-based simulation model describing the relation between 14 HPV types and cervical disease, allowing the occurrence of multiple type infections. Screening scenarios for vaccinated women were evaluated, firstly for HPV16/18 vaccination with partial cross-protection against HPV 31, 33, 45 and 58 and secondly, for broad spectrum vaccination against 5-13 HPV types. The vaccine-induced incidence reduction of type-specific infection was varied from 0 to 95% in the cross-protection setting and set at 100% in the setting of broad spectrum vaccines. Scenarios of either cytology or HPV DNA screening were considered under varying lifetime number of screening rounds. At a cost-effectiveness threshold of €20,000/QALY, four times HPV DNA screening between 30 and 60 years was the selected scenario in addition to HPV16/18 vaccination, whether or not cross-protection was conferred (€6707 and €9994/QALY, respectively). In the absence of cross-protection, a fifth screening round might be considered (ICER €22,967/QALY). In addition to broad spectrum vaccination, one screen during lifetime was cost-effective up to an 11-valent vaccine. If the vaccine-induced type-specific incidence reduction was lowered to 99%, one screen during lifetime was cost-effective even in addition to 13-valent vaccination. In conclusion, in a cohort of HPV16/18 vaccinated women, four rounds of HPV DNA screening is cost-effective. One screen during lifetime remains cost-effective in addition to broad spectrum vaccination offering protection against many high-risk HPV types.

The impact of anogenital warts on health-related quality of life: a 6-month prospective study.

BACKGROUND: The burden of anogenital warts will be a determining factor when making decisions about the type of human papillomavirus (HPV) vaccine to be used (bivalent or quadrivalent) and whether to vaccinate males. We conducted a multicenter prospective study to (1) describe the impact of anogenital warts on quality of life and (2) estimate the quality-adjusted life-years (QALYs) lost due to anogenital warts. METHODS: Between September 2006 and February 2008, 272 patients with a first or recurrent episode of anogenital warts were recruited from the clinical practices of 42 physicians across Canada. Quality of life was measured at recruitment, and 2 and 6 months later with the EuroQol, Short Form-12, short Spielberg State-Trait Anxiety Inventory, and HPV impact profile. The duration of an episode and QALYs lost due to anogenital warts were estimated among 51 incident cases recruited within 90 days of disease onset. RESULTS: Anogenital warts had a significant impact on the quality of life. This negative impact was similar for first and recurrent episodes, and lasted as long as lesions persisted. Anogenital warts had the greatest negative impact on usual activities, pain/discomfort, and anxiety/depression, and on self-image, sexual activity, and partner issues and possible transmission. The median duration of a first anogenital wart episode amongst incident cases was 125 days and resulted in QALYs lost of 0.017 to 0.041, which is equivalent to 6 to 15 days of healthy life lost. CONCLUSIONS: The burden of anogenital warts is substantial and should be considered by physicians and public health officials when making recommendations about HPV vaccination..

Distribution of human papillomavirus genotypes among cervical intraepithelial neoplasia and invasive cancers in Macao.

Macao is a densely populated city situated in East Asia where a relatively high prevalence of human papillomavirus (HPV) types 52 and 58 has been reported in women with invasive cervical cancer. To provide data for a population-specific estimation on the impact of HPV vaccines, paraffin-embedded tissues collected from women with invasive cervical cancer or cervical intrapeitheilal neoplasia grade 2 or 3 confirmed histologically were examined for HPV using the INNO-LiPa kit. Of the 35 HPV-positive patients with invasive cancer, one HPV type was detected in 68.6%, and 31.4% were co-infected with more than one HPV type. Overall, HPV 16, HPV 18, HPV 52, and HPV 54 were the most common types found respectively in 57.1%, 17%, 11.4%, and 8.5% of patients with invasive cervical cancer. Among the 59 HPV-positive patients with cervical intraepithelial neoplasia grade 2/3, 55.9% hardbored one HPV type, and 44.1% had co-infections. The common HPV types found included HPV 16 (52.5%), HPV 52 (23.7%), HPV 58 (18.7%), and HPV 33 (17%). Although HPV 11 (a low-risk type) was also found commonly in invasive cervical cancers (14.3%) and cervical intraepithelial neoplasia grade 2/3 (15.3%), the fact that they all existed as co-infections with another high-risk type suggested HPV 11 was not the cause of the lesion. The current vaccines targeting HPV 16/18 are expected to cover 62.9-74.3% of invasive cervical cancers and 32.2-55.9% of cervical intraepithelial neoplasia 2/3 in Macao. Widespread HPV vaccination is expected to reduce substantially the disease burden associated with cervical neoplasia in Macao.

Human papillomavirus disease and vaccines.

PURPOSE: Human papillomavirus (HPV) disease and vaccines and several controversial issues associated with vaccine administration are reviewed. SUMMARY: HPV infection is the most common sexually transmitted disease in the United States. It is estimated that 20 million individuals are currently infected with HPV, with 6.2 million new infections occurring each year. Although most HPV infections are benign and are often cleared without clinical sequelae, persistent infections are associated with the development of cervical cancer in women and genital warts in both women and men. The identification of the most common disease-causing HPV types has led to the development of a quadrivalent vaccine and a bivalent vaccine. The prophylactic administration of the quadrivalent vaccine has resulted in a 96% efficacy in preventing persistent infection associated with HPV types 6, 11, 16, and 18. Similar to the quadrivalent vaccine, the bivalent vaccine is highly efficacious (96%) in preventing persistent infection against vaccine-specific HPV types (HPV-16 and HPV-18) among women who were HPV seronegative at the time of vaccination. However, many controversial issues still remain regarding routine administration and widespread acceptance. These include appropriate age at time of vaccination, parental concerns, vaccination of men or women age 26 years or older, inadequate long-term efficacy and safety data, and potential for nonvaccine-related strains to emerge as prominent oncogenic serotypes. CONCLUSION: HPV vaccines provide a high level of protection for seronegative women against persistent infection and precancerous cervical lesions associated with vaccine-specific HPV types. However, many controversial issues still remain regarding the vaccines' routine administration and widespread acceptance.

Cost-effectiveness analysis of adding a quadrivalent HPV vaccine to the cervical cancer screening programme in Switzerland.

OBJECTIVE: Based on positive safety and efficacy data, a quadrivalent Human PapillomaVirus (HPV) vaccine has been approved in Switzerland to prevent HPV types 6, 11, 16 and 18 infections. The objective of this study was to explore the cost-effectiveness of an HPV vaccination in Switzerland. DESIGN AND METHODS: A Markov model of the natural history of HPV infection was adapted to the Swiss context and followed a hypothetical cohort of 41,200 girls aged 11 years over their lifetime. Main epidemiological and economic parameters were extracted from the literature. Two strategies were compared: conventional cytological screening only and HPV vaccination followed by conventional cytological screening. A coverage rate of 80% was used and the vaccine was assumed to provide a lifelong protection. Analyses were performed from the direct health care cost perspective including only direct medical costs. RESULTS: Compared to screening only, adding a quadrivalent HPV vaccine could prevent over lifetime 62% of cervical cancers and related deaths, 19% of Cervical Intraepithelial Neoplasia (CIN 1), 43% of CIN 2, 45% of CIN 3 and 66% of genital warts per cohort. Incremental cost-effectiveness ratios (ICER) were estimated to be CHF 45,008 per Life Year Gained (LYG) and CHF 26,005 per Quality Adjusted Life Year (QALY) gained. Sensitivity analyses demonstrated that the ICER was robust to all parameters, but was most sensitive to the need for a booster and discount rates. CONCLUSIONS: Compared to commonly accepted standard thresholds in Europe and other vaccination strategies implemented in Switzerland, adding a quadrivalent HPV vaccine alongside the current cervical cancer screening programme is likely to be cost-effective in Switzerland.

Cost-effectiveness analysis of the introduction of a quadrivalent human papillomavirus vaccine in France.

OBJECTIVES: A vaccine to prevent diseases due to human papillomavirus (HPV) types 6, 11, 16, and 18 is now available in France. The objective of this study was to assess the health and economic impact in France of implementing a quadrivalent HPV vaccine alongside existing screening practices versus screening alone. METHODS: A Markov model of the natural history of HPV infection incorporating screening and vaccination, was adapted to the French context. A vaccine that would prevent 100 percent of HPV 6, 11, 16, and 18-associated diseases, with lifetime duration and 80 percent coverage, given to girls at age 14 in conjunction with current screening was compared with screening alone. Results were analyzed from both a direct healthcare cost perspective (DCP) and a third-party payer perspective (TPP). Indirect costs such as productivity loss were not taken into account in this analysis. RESULTS: The incremental cost per life-year gained from vaccination was euro12,429 (TPP) and euro20,455 (DCP). The incremental cost per quality-adjusted life-year (QALY) for the introduction of HPV vaccination alongside the French cervical cancer screening program was euro8,408 (TPP) and euro13,809 (DCP). Sensitivity analyses demonstrated that cost-effectiveness was stable, but was most sensitive to the discount rate used for costs and benefits. CONCLUSIONS: Considering the commonly accepted threshold of euro50,000 per QALY, these analyses support the fact that adding a quadrivalent HPV vaccine to the current screening program in France is a cost-effective strategy for reducing the burden of cervical cancer, precancerous lesions, and genital warts caused by HPV types 6, 11, 16, and 18.