Sustained efficacy up to 4.5 years of a bivalent L1 virus-like particle vaccine against human papillomavirus types 16 and 18: follow-up from a randomised control trial

HPV-specific antibodies in female genital tract secretions captured via first-void urine retain their neutralizing capacity

Human papillomavirus (HPV) vaccines, primarily relying on neutralizing antibodies, have proven highly effective. Recently, HPV-specific antibodies have been detected in the female genital tract secretions captured by first-void urine (FVU), offering a minimally invasive diagnostic approach. In this study, we investigated whether HPV16-specific antibodies present in FVU samples retain their neutralizing capacity by using pseudovirion-based neutralization assays. Paired FVU and serum samples (vaccinated n = 25, unvaccinated n = 25, aged 18-25) were analyzed using two orthogonal pseudovirion-based neutralization assays, one using fluorescence microscopy and the other using luminescence-based spectrophotometry. Results were compared with HPV16-specific IgG concentrations and correlations between neutralizing antibodies in FVU and serum were explored. The study demonstrated the presence of neutralizing antibodies in FVU using both pseudovirion-based neutralization assays, with the luminescence-based assay showing higher sensitivity for FVU samples, while the fluorescence microscopy-based assay exhibited better specificity for serum and overall higher reproducibility. High Spearman correlation values were calculated between HPV16-IgG and HPV16-neutralizing antibodies for both protocols (rs: 0.54-0.94, p < .001). Significant Spearman correlations between FVU and serum concentrations were also established for all assays (rs: 0.44-0.91, p < .01). This study demonstrates the continued neutralizing ability of antibodies captured with FVU, supporting the hypothesis that HPV vaccination may reduce autoinoculation and transmission risk to the sexual partner. Although further protocol optimizations are warranted, these findings provide a foundation for future research and larger cohort studies that could have implications for the optimal design, evaluation, and implementation of HPV vaccination programs.

Determinants of Parental Intention to Vaccinate Young Adolescent Girls against the Human Papillomavirus in Taiwan: An Online Survey Study

Since 2018, Taiwan has included the human papillomavirus (HPV) vaccination into its national immunization program for junior high school girls. However, the reports of side effects following vaccination have increased parental concerns. This study investigated parental intentions regarding the HPV vaccination for their daughters and related factors in Taiwan. A total of 213 parents of girls aged between 12 and 15 years participated in an online survey. The survey collected data on various factors, including the parental intention to vaccinate their daughters against HPV; the motivation behind the vaccinations, as measured using the Motors of Human Papillomavirus Vaccination Acceptance Scale; an understanding of the reasons behind the government's promotion of HPV vaccinations; concerns regarding the side effects of vaccinations for their daughters; an awareness of the reported side effects of HPV vaccines experienced by some individuals; the exposure to information on HPV vaccines from social media; and mental health status, measured using the Brief Symptom Rating Scale. The associations between these variables and the parental intention to vaccinate their daughters against HPV were examined using a multivariable linear regression analysis model. The findings revealed a moderate to high level of intention among participants to vaccinate their daughters against HPV. Parents who perceived a greater value in HPV vaccination for their daughters' health (B = 0.524, standard error [se] = 0.039, p < 0.001) and had greater autonomy in decision-making regarding vaccination (B = 0.086, se = 0.038, p = 0.026) exhibited a higher intention to vaccinate their daughters against HPV. Conversely, parents who expressed greater concern regarding the side effects of HPV vaccines for their daughters had a lower intention to vaccinate (B = -0.762, se = 0.203, p < 0.001). Based on these findings, this study recommends integrating these factors into the design of intervention programs aimed at enhancing parental intentions to vaccinate their daughters against HPV.

Scientific approaches toward improving cervical cancer elimination strategies

At the 2023 EUROGIN workshop scientific basis for strategies to accelerate the elimination of cervical cancer and its causative agent, human papillomavirus (HPV) were reviewed. Although some countries have reached key performance indicators toward elimination (>90% of girls HPV vaccinated and >70% of women HPV screened), most are yet to reach these targets, implying a need for improved strategies. Gender-neutral vaccination, even with moderate vaccination coverage was highlighted as a strategy to achieve elimination more rapidly. It is more resilient against major disturbances in vaccination delivery, such as what happened during the coronavirus pandemic. Further, an analysis of ethical/legal issues indicated that female-restricted vaccination is problematic. Extended catch-up of vaccination with concomitant screening, and outreach to vulnerable groups were highlighted. Although birth cohorts with high coverage of HPV vaccination at school are protected against HPV, and HPVs have a very low reproductive rate in women above age 35, adult women below age 30 have inadequate direct protection. In addition to herd protection from gender-neutral vaccination, this group can be protected by offering concomitant catch-up HPV vaccination and HPV screening. Furthermore, hepatitis B vaccination experiences indicate that elimination cannot be achieved without prioritizing vulnerable/migrant populations. The long-lasting durability of vaccination-induced antibody responses suggests prolonged protection with HPV vaccines when adequately administrated. Finally, cost-effectiveness modelling suggests that high-coverage HPV vaccination in multiple population segments will be resource-saving due to reduced need for screening. In summary, the workshop found that strategically optimal deployment of vaccination will accelerate elimination of HPV and cervical cancer.

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

BACKGROUND

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.

MATERIALS AND METHODS

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).

RESULTS

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.

CONCLUSION

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.

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

Background

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.

Method

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.

Results

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).

Conclusion

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.

High rate of non-vaccine targeted high-risk HPV genotypes circulate among women in Eastern Ethiopia

The World Health Organization [WHO] recommends a genotype-specific human papillomavirus [HPV] vaccination as a primary prevention strategy to control the burden of cervical cancer globally. In Ethiopia, where the non-vaccine-targeted HPV genotypes have not been adequately studied, a vaccination initiative was launched in 2018 targeting HPV-6,-11, -16, and -18 for girls aged 14-18 years. The co-existence of both vaccine-targeted and non-targeted genotypes is a serious concern, as it can accelerate cancer progression. Therefore, this study was conducted to determine the prevalence of non-vaccine-targeted HPV genotypes and assess the level of multiple infections with other genotypes in eastern Ethiopia. A health facility-based cross-sectional study including 110 women with positive HPV DNA results was conducted from April to August 2021. A structured questionnaire to collect demographic and clinical data was used. Cervical swabs were collected using L-shaped FLOQSwabs. Women's cytological profile was determined based on Pap smear test results. An automated nucleic acid extraction system using STARMag 96 ProPrep Universal Extraction Kit was utilized following the manufacturer's protocol. An amplification assay in real-time was employed to amplify and identify the HPV Late 1 [L1] gene, which is utilized for genotyping purposes. Following this, the collected data was entered into Epi data version 3.1 software, and the analysis was performed using STATA version 14. A total of 110 women [age range 30-60 years, mean age = 36.5 years and SD ± 6.9] had positive HPV DNA results and were included in the study. Among these, 108 women had valid co-testing [Pap test and HPV DNA test] results for further analysis, and the results of the remaining 2 women were rejected. Overall, the prevalence of non-vaccine-targeted HPV was 56 (51.8%, 95%CI [0.42, 0.61]), of which 28 women (25.4%, 95%CI [0.18, 0.34]) had a single non-vaccine HPV genotype infection. The remaining 29 women (26.4%, 95% CI: 0.190-0.355) experienced multiple infections. The non-vaccine-targeted genotypes of HPV-35 accounted for 11 cases (10%, 95%CI [0.06, 0.17]), HPV-68 was detected in 9 women (8.2%, 95%CI [0.04, 0.15]), HPV-56 and HPV-66 were both found in 8 cases each (7.3%, 95%CI [0.04, 0.14]) of the total. In addition, out of these 108 women, 93 (86.1%, 95%CI [0.78, 0.91]) had low-grade squamous intraepithelial lesions, 13 (12%, 95%CI [0.07, 0.20]) no intraepithelial lesion or malignancy, and two (1.9%, 95%CI [0.01, 0.07]) high-grade squamous intraepithelial lesions. Furthermore, there was no statistical difference [p = 0.755] between vaccine-targeted and non-vaccine-targeted genotypes as the primary cause of cervical lesions. In conclusion, the findings of the present study highlight the existence of a notable prevalence of multiple infections caused by non-vaccine-targeted HPV genotypes. Therefore, it is recommended that both the Federal and regional health bureaus to evaluate the range of hr HPV genotypes protected by the current HPV vaccine and explore the option of transitioning from the quadrivalent HPV vaccine to a novavalent vaccine that includes seven high-risk HPV genotypes.

Human papillomavirus vaccine uptake and associated factors among adolescent girls in high schools of Nekemte city, Western Ethiopia, 2020

BACKGROUND

Cervical cancer is the leading cause of cancer death in adult women in the developing world including Ethiopia. To combat cervical cancer, the World Health Organization (WHO) recommends that girls aged 9-14 years have to take the human papillomavirus vaccine. However, there is a lack of information regarding the uptake of human papillomavirus vaccine in the study area. Therefore, this study aimed to assess the Human Papilloma Virus vaccine uptake and associated factors among adolescent girls in high schools of Nekemte City, Western Ethiopia, 2020.

METHODS

A cross-sectional study design was employed among adolescent girls attending grade 9 and age 15 enrolled at schools in Nekemte City from July 15-30, 2020. Six hundred twenty-six (626) randomly selected adolescent girls were interviewed. The data were entered into Epi Info 7 and analyzed by SPSS 25. Multivariable analysis was computed and a P-value < 0.05 was taken as a cut-off point to declare the statistically significant association.

RESULT

The uptake of the HPV vaccine was 61.2%, 95%CI (57.2%, 65%). The Place where adolescents grow up (AOR = 3.46, 95%CI [1.95,6.15]), having a mobile phone(AOR = 1.71, 95%CI [1.05, 2.79]), ever heard about HPV (AOR = 5.69, 95%CI [1.33, 24.27]), ever heard about HPV vaccine(AOR = 1.917, 95%CI [1.002, 3.667]), Ever had sexual intercourse (AOR = 3.04, 95% [1.49,6.20]) and Perceived risk of towards HPV(AOR = 4.63 [2.49, 8.63]) has shown statistically significant association with Uptake of the HPV vaccine.

CONCLUSION

Nearly two-thirds of the study participants had taken at least one dose of the HPV vaccine. It is better if health information on HPV is disseminated considering the available technology like mobile phones and reaching rural girls.

Trust in Physicians in the Context of HPV Vaccination of Children from the Perspective of Social Exchange Theory: A Representative Study of Polish Parents

The vaccination of children against human papillomavirus (HPV) effectively prevents HPV infection and HPV-related cancers in women and men. However, HPV vaccination programs are met with vaccine hesitancy, which varies between countries. The coverage in Poland is low, although introducing nationally funded HPV vaccination for girls aged 12-13 in mid-2023 may increase it. The uptake of the HPV vaccine in adolescents is highly affected by parental decisions, which in turn can be influenced by interactions with the physician. The present representative study aimed to analyze the acceptance of the HPV vaccine among Polish parents (n = 360) and the level of trust in HPV vaccination in the pediatrician/general practitioner who takes care of their children aged 9-15 years. The data were gathered in September 2022 using computer-assisted telephone interviews. Most surveyed parents reported trusting their child's physician regarding vaccine recommendations (89.2%) and vaccinated their child with all or most of the vaccines recommended by a national vaccination guideline (94.7%). However, 13.3% declared themselves as moderate or strong vaccine opponents, a group characterized by high (83.4%) distrust in physicians. There was no difference in the awareness of HPV in groups varying in trusting the physicians, but parents who trusted them were more frequently aware of the HPV vaccine. Parental willingness to vaccinate their child against HPV was highly differentiated by the level of trust in the child's physician. The results highlight that trust in physicians is a critical factor shaping decisions for children's vaccination, stressing a continuous need to improve strategies to communicate with patients.

Comparison of the Immune Responses to Different Formulations of BC02-Adjuvanted HPV Types 16 and 18 Bivalent Vaccines in Mice

To achieve maximum efficacy, vaccines, such as subunit, recombinant, and conjugate vaccines, necessitate the incorporation of immunostimulators/adjuvants. Adjuvants play a vital role in bolstering and extending the strength of the immune response while also influencing its type. As antigen and adjuvant formulations become more intricate, it becomes imperative to establish a well-characterized and robust formulation to ensure consistent and reproducible outcomes in preclinical and clinical studies. In the present study, an HPV bivalent vaccine was developed using a BC02 adjuvant in conjunction with HPV 16 and 18 L1 VLP antigens produced from an E. coli expression system. The study involved evaluating the adjuvant formulation and in vivo immunogenicity in mice. Remarkably, a medium-dose of BCG-CpG-DNA combined with a low-dose of aluminum hydroxide substantially enhanced the immunogenicity of HPV16 and 18 VLPs, resulting in improved cellular and humoral immune responses.

Recent Developments in Human Papillomavirus (HPV) Vaccinology

Human papillomavirus (HPV) is causally associated with 5% of cancers, including cancers of the cervix, penis, vulva, vagina, anus and oropharynx. The most carcinogenic HPV is HPV-16, which dominates the types causing cancer. There is also sufficient evidence that HPV types 18, 31, 33, 35, 39, 45, 51, 52, 56, 58 and 59 cause cervical cancer. The L1 protein, which, when assembled into virus-like particles, induces HPV-type-specific neutralising antibodies, forms the basis of all commercial HPV vaccines. There are six licensed prophylactic HPV vaccines: three bivalent, two quadrivalent and one nonavalent vaccine. The bivalent vaccines protect from HPV types 16 and 18, which are associated with more than 70% of cervical cancers. Prophylactic vaccination targets children before sexual debut, but there are now catch-up campaigns, which have also been shown to be beneficial in reducing HPV infection and disease. HPV vaccination of adults after treatment for cervical lesions or recurrent respiratory papillomatosis has impacted recurrence. Gender-neutral vaccination will improve herd immunity and prevent infection in men and women. HPV vaccines are immunogenic in people living with HIV, but more research is needed on the long-term impact of vaccination and to determine whether further boosters are required.

Barriers and facilitators of HPV vaccination in sub-saharan Africa: a systematic review

BACKGROUND

Human Papilloma Virus (HPV) is the most common sexually transmitted infection worldwide. Globally, both men and women have a 50% risk of being infected at least once in their life. HPV prevalence is among the highest in sub-Saharan Africa (SSA), at an average of 24%. HPV causes different types of cancers, including cervical cancer (CC), which is the leading cause of cancer deaths among women in SSA. HPV-vaccination has been proven to be effective in reducing HPV induced cancers. SSA countries are delayed in reaching the WHO's target of fully vaccinating 90% of girls within the age of 15 by 2030. Our systematic review aims to identify barriers and facilitators of HPV-vaccination in SSA to inform national implementation strategies in the region.

METHODS

This is a mixed method systematic review based on the PRISMA statement and The Joanna Briggs Institute Reviewers' Manual. Search strategies were adapted to each selected database: PubMed/MEDLINE, Livivo, Google Scholar, Science Direct, and African Journals Online for papers published in English, Italian, German, French and Spanish between 1 December 2011 and 31 December 2021. Zotero and Rayyan were the software used for data management. The appraisal was conducted by three independent reviewers.

RESULTS

A total of 20 articles were selected for appraisal from an initial 536 articles. Barriers included: limited health system capacities, socio-economic status, stigma, fear and costs of vaccines, negative experience with vaccinations, COVID-19 pandemic, lack of correct information, health education (HE) and consent. Additionally, we found that boys are scarcely considered for HPV-vaccination by parents and stakeholders. Facilitators included: information and knowledge, policy implementation, positive experience with vaccinations, HE, stakeholders' engagement, women's empowerment, community engagement, seasonality, and target-oriented vaccination campaigns.

CONCLUSIONS

This review synthesizes barriers and facilitators of HPV-vaccinations in SSA. Addressing these can contribute to the implementation of more effective HPV immunization programs targeted at eliminating CC in line with the WHO 90/70/90 strategy.

REGISTRATION AND FUNDING

Protocol ID: CRD42022338609 registered in the International Prospective Register of Systematic Reviews (PROSPERO). Partial funds: German Centre for Infection research (DZIF) project NAMASTE: 8,008,803,819.

Bridging the immunogenicity of a tetravalent dengue vaccine (TAK-003) from children and adolescents to adults

Immunobridging is an important methodology that can be used to extrapolate vaccine efficacy estimates to populations not evaluated in clinical studies, and that has been successfully used in developing many vaccines. Dengue, caused by a mosquito-transmitted flavivirus endemic to many tropical and subtropical regions, is traditionally thought of as a pediatric disease but is now a global threat to both children and adults. We bridged immunogenicity data from a phase 3 efficacy study of a tetravalent dengue vaccine (TAK-003), performed in children and adolescents living in endemic areas, with an immunogenicity study in adults in non-endemic areas. Neutralizing antibody responses were comparable in both studies following receipt of a two-dose TAK-003 schedule (months 0 and 3). Similar immune responses were observed across exploratory assessments of additional humoral responses. These data support the potential for clinical efficacy of TAK-003 in adults.

HPV pathogenesis, various types of vaccines, safety concern, prophylactic and therapeutic applications to control cervical cancer, and future perspective

Over 98% of cervical cancers (CC) are caused by regular infections with "high risk" genotype of the human papilloma virus (HPV). However, this is not always the causative factor. Therefore, production of HPV vaccinations represents a significant chance to minimize the risk of CC. Phase III studies for a number of preventative HPV vaccines based on L1-virus-like particle (VLPs) have just been completed and the preliminary results are very convincing. However, there are a lot of practical concerns that need to be resolved before the use of these vaccinations. These vaccines were challenged with obvious queries such as protection time, subject receiving vaccines, time of vaccination, and how to include them into ongoing screening programs. Although these vaccines were 90% effective at preventing HPV infection as these offered only modest advantages for the removal of pre-existing infections. New advancements in the creation of therapeutic vaccinations have been explored for further improvement and post-vaccination surveillance. Therapeutic vaccines attempted to boost cell-mediated immunities and these are detrimental to the infected cell as opposed to neutralizing antibodies (different from prophylactic vaccines).

Molecular Mechanism behind the Safe Immunostimulatory Effect of Withania somnifera

Withania somnifera (L.) Dunal (family Solanaceae) is a medicinal plant known for, among many pharmacological properties, an immune boosting effect. Our recent study revealed that its key immunostimulatory factor is lipopolysaccharide of plant-associated bacteria. This is peculiar, because, although LPS can elicit protective immunity, it is an extremely potent pro-inflammatory toxin (endotoxin). However, W. somnifera is not associated with such toxicity. In fact, despite the presence of LPS, it does not trigger massive inflammatory responses in macrophages. To gain insights into the safe immunostimulatory effect of W. somnifera, we conducted a mechanistic study on its major phytochemical constituent, withaferin A, which is known for anti-inflammatory activity. Endotoxin-triggered immunological responses in the presence and absence of withaferin A were characterized by both in vitro macrophage-based assay and in vivo cytokine profiling in mice. Collectively, our results demonstrate that withaferin A selectively attenuates the pro-inflammatory signaling triggered by endotoxin without impairing other immunological pathways. This finding provides a new conceptual framework to understand the safe immune-boosting effect of W. somnifera and possibly other medicinal plants. Furthermore, the finding opens a new opportunity to facilitate the development of safe immunotherapeutic agents, such as vaccine adjuvants.

Trends in research related to vaccine and cancer prevention from 1992 to 2022: A 30-years bibliometric analysis

Vaccines may play an important role in cancer prevention. This bibliometric study in the field of vaccine and cancer prevention is designed to evaluate key research advances, identify existing deficiencies, and provide reference for future investigations. A total of 2916 original articles published in English from 1992 to 2022 were extracted from the Web of Science core collection. America (1,277) and the National Cancer Institute (82) were the most productive country and institution in this field, respectively. Vaccine was not only the most co-cited journal but also the most influential. Garland SM was the most prolific author, and Bosch FX was the most influential co-cited author. The keywords "cervical cancer" had the highest frequency. "Nanovaccines," "vaccine acceptance" and "coverage" were the new research hotspots in this field. Currently, although an increasing number of publications involve vaccine and cancer prevention studies, most of them are related to cervical cancer, and few other cancers, suggesting the need to investigate other cancer prevention vaccines. The promising research hotspots, such as nanovaccines, vaccine acceptance, and vaccine coverage should be the focus of investigation. The study provides the current status and trends in clinical research on vaccine and cancer prevention, enabling researchers to identify hotspots and explore new study directions. In the future, vaccines are expected to play a key role in multiple cancer prevention.

Regression rate of high-grade cervical intraepithelial lesions in women younger than 25 years

BACKGROUND/PURPOSE

The incidence and clinical course of high-grade cervical intraepithelial lesions (CIN 2/3) are age dependent. In CIN 3, the recommended treatment is conization, which increases the risk of cervical insufficiency or premature deliveries. But data concerning spontaneous regression of CIN 3 are rare.

METHODS

Between 2007 and 2017, we identified 156 women under the age of 25 with CIN 2 (23%) or CIN 3 (77%), who had a consultation and were treated at the Colposcopy Unit, Hospital of Düsseldorf, Germany. This is a retrospective cohort study. These patients had colposcopical follow-ups every 4-6 months. Moreover, we analyzed various parameters to predict regression of cervical lesions in this age group.

RESULTS

Patients diagnosed with CIN 2 showed regression in 88% (n = 30) and women with CIN 3 had a regression rate of 29% (n = 34). Complete regression was observed in 86.7% of CIN 2 and 47.1% of CIN3. Mean time to regression was 21 M (months) [2-70 M]. 70.9% of the patients were treated by surgery (LEEP) after persistence or progression. We identified several predictors for regression of CIN 2/3 in young women: the regression rate of CIN2 is significantly higher than CIN 3 (p < 0.001). Clearance of HPV infections had significantly higher rates of regression compared to persisting HPV infections (p < 0.001). HPV-vaccinated women showed significantly higher regression rates (p = 0.009).

CONCLUSIONS

These data show that an expectative close follow-up in women with CIN 3 younger than 25 is possible with regression rates of 29% also for CIN 3. Especially in women who were HPV vaccinated and those who cleared their HPV infection. A frequent colposcopical follow-up every 3-4 months is important for CIN 3 and every 6 months for CIN 2.

Human papillomavirus vaccination coverage among sexually active young adults aged 18 to 26 at a sexually transmitted infections clinic

BACKGROUND

Human papillomavirus (HPV) vaccination is the most effective biomedical intervention for HPV infections. HPV vaccination rate among sexually active young adults is largely unknown.

METHODS

Patients aged 18-26 years, who attended the Rhode Island Sexually Transmitted Infections Clinic between 2013-2018, were included in the study. We extracted demographics, behavioral characteristics, and HPV vaccination status from electronic medical records. Exploratory logistic regressions were conducted to identify factors associated with vaccination status.

RESULTS

Among 2729 eligible individuals, the median age was 23 years (interquartile range: 22-25). Only 8.1% of males and 24.8% of females received at least one dose of HPV vaccine. Females were 144% (crude odds ratio [cOR]: 2.44, 95% confidence interval [CI]: 2.03, 2.94) more likely to receive at least one dose of HPV vaccine than males. Being Black/African American (B/AA) or Hispanic/Latino (H/L) was associated with a 21% (cOR: 0.79, 95% CI: 0.62, 1.00) and 34% (cOR: 0.66, 95% CI: 0.53, 0.81) decrease in the odds of vaccination, respectively.

CONCLUSIONS

HPV vaccination rate was low among sexually active young adults. Gender and racial/ethnic disparities existed in HPV vaccination. Interventions are needed to promote HPV vaccination among sexually active young adults, especially B/AA and H/L communities.

Comparative efficacy of human papillomavirus vaccines: systematic review and network meta-analysis

OBJECTIVES

Despite their use, differences in human papillomavirus (HPV) vaccine efficacies remain uncertain. This study assesses efficacy differences among bivalent, quadrivalent, and nine-valent HPV (2vHPV, 4vHPV, and 9vHPV) vaccines.

METHODS

PubMed, Web of Science, Embase, and the Cochrane Library were searched for randomized controlled trials comparing HPV vaccine efficacy against persistent infection (≥6 months) and cervical intraepithelial neoplasia grade 2 or worse (CIN2+). Network meta-analysis yielded direct and indirect comparisons. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were reported, and robustness was evaluated via sensitivity analysis.

RESULTS

In 11 randomized controlled trials with 58,881 healthy women, for persistent infection with HPV 16, 9vHPV was most effective at 97% (RR = 0.03, 95% CI: 0.01-0.08); for HPV 18, 2vHPV (Cecolin) was most effective at 98% (RR = 0.02, 95% CI: 0.00-0.29); for CIN2+ associated with HPV 16 and 18, 4vHPV was most effective at 99% (RR = 0.01, 95% CI: 0.00-0.10) and 97% (RR = 0.03, 95% CI: 0.00-0.45), respectively; for persistent infection with HPV 31, 33, 45, 52, and 58, 9vHPV was ≥ 95% effective; both 2vHPV vaccines were cross-effective against HPV 31, 33, and 45; and 4vHPV was cross-effective against HPV 31.

CONCLUSIONS

HPV vaccine efficacies differ for different HPV types. Additional data are needed to determine the cross-efficacy of 2vHPV (Cecolin).

Mutation Profile of HPV16 L1 and L2 Genes in Different Geographic Areas

The causal relationship between HPV and cervical cancer in association with the high prevalence of high risk HPV genotypes led to the design of HPV vaccines based on the major capsid L1 protein. In recent years, capsid protein L2 has also become a focal point in the field of vaccine research. The present review focuses on the variability of HPV16 L1 and L2 genes, emphasizing the distribution of specific amino acid changes in the epitopes of capsid proteins. Moreover, a substantial bioinformatics analysis was conducted to describe the worldwide distribution of amino acid substitutions throughout HPV16 L1, L2 proteins. Five amino acid changes (T176N, N181T; EF loop), (T266A; FG loop), (T353P, T389S; HI loop) are frequently observed in the L1 hypervariable surface loops, while two amino acid substitutions (D43E, S122P) are adjacent to L2 specific epitopes. These changes have a high prevalence in certain geographic regions. The present review suggests that the extensive analysis of the amino acid substitutions in the HPV16 L1 immunodominant loops may provide insights concerning the ability of the virus in evading host immune response in certain populations. The genetic variability of the HPV16 L1 and L2 epitopes should be extensively analyzed in a given population.

Long-Term immunopersistence and safety of the Escherichia coli-produced HPV-16/18 bivalent vaccine in Chinese adolescent girls

The study assessed long-term immunopersistence and safety of the Escherichia coli (E. coli)-produced HPV-16/18 bivalent vaccine. In total, 979 participants in the initial immunogenicity noninferiority study, including girls aged 9-14 years who were randomized in a 1:1 ratio to receive 2 doses at months 0 and 6 (n = 301) or 3 doses at months 0, 1 and 6 (n = 304); girls aged 15-17 years (n = 149) and women aged 18-26 years (n = 225) who received 3 doses of the vaccine, were invited to participate in follow-up to 30 months post vaccination (NCT03206255). Serum samples were collected at months 18 and 30, and anti-HPV-16/18 IgG antibodies were measured by enzyme-linked immunosorbent assay. Serious adverse events (SAEs) occurred from month 7 through month 30 were recorded. At month 30, in the per-protocol set, all participants remained seropositive, except for one girl in the 9-14 years (2 doses) group who seroconverted to negative for HPV-18. HPV-16 and HPV-18 antibody levels were higher in girls aged 9-17 years who received 3 doses (125.3 and 60.2 IU/ml) than in women aged 18-26 years who received 3 doses (72.6 and 28.3 IU/ml), and those in girls aged 9-14 years who received 2 doses (73.2 and 24.9 IU/ml) were comparable to those in women aged 18-26 years who received 3 doses. No SAEs were reported to be causally related to vaccination. The E. coli-produced bivalent HPV-16/18 vaccine is safe and induces persistent protective antibodies for up to 30 months after vaccination in girls aged 9-17 years receiving 2 or 3 doses.

Human Papillomavirus-Associated Head and Neck Cancers. Where are We Now? A Systematic Review

BACKGROUND

Human papillomavirus targets the skin and mucous membranes, producing benign hyperplastic lesions and precancerous and cancerous lesions. An increasing number of head and neck cancersin particular, oropharyngeal squamous cell carcinoma, laryngeal squamous cell carcinoma, and oral squamous cell carcinoma, are attributable to HPV infection. HPV-induced HNCs typically affect younger, nonsmoking patients with no prior history of heavy alcohol use, more extensive sexual history, and higher socioeconomic status.

AIM

The purpose of the review is to present the most recent and well-established findings concerning HPV-induced head and neck cancers and consequently to provide medical specialists with essential information regarding the epidemiology, the role of HPV in HNC cancerogenesis, prevention, diagnosis, and treatment.

MATERIAL AND METHODS

All authors independently have searched The EMbase, Medline/Pubmed, and Cochrane databases by using the following keywords "head and neck cancer", "human papillomavirus", "HPV", "HPV biology", "oropharyngeal squamous cell carcinoma", "carcinogenesis", "transoral surgery", "robotic surgery". The last search was conducted in March 2022. The references of the publications of interest were also screened for relevant papers. There were no limitations in regard to the publication date.

CONCLUSION

Aiming to avoid the epidemic of HPV-induced HNC, it is paramount to improve the access to vaccination as well as resolve parental concerns regarding vaccine safety. Physicians should rely on reduced-dose radiation and aim to reduce the overall treatment time. Thanks to a more elaborate understanding of the genomic background of HPV-induced HNC, precision medicine could become a relevant part of patients' management. In comparison to traditional techniques and non-operative treatment, transoral robotic surgery (TORS) offers similar oncologic and functional outcomes, with a possible benefit on long-term quality of life. However, more research is needed to establish clear guidelines indicating when TORS resections should be supported with adjuvant therapy.

Recent Advances in Cancer Vaccines: Challenges, Achievements, and Futuristic Prospects

Cancer is a chronic disease, and it can be lethal due to limited therapeutic options. The conventional treatment options for cancer have numerous challenges, such as a low blood circulation time as well as poor solubility of anticancer drugs. Therapeutic cancer vaccines emerged to try to improve anticancer drugs' efficiency and to deliver them to the target site. Cancer vaccines are considered a viable therapeutic technique for most solid tumors. Vaccines boost antitumor immunity by delivering tumor antigens, nucleic acids, entire cells, and peptides. Cancer vaccines are designed to induce long-term antitumor memory, causing tumor regression, eradicate minimal residual illness, and prevent non-specific or unpleasant effects. These vaccines can assist in the elimination of cancer cells from various organs or organ systems in the body, with minimal risk of tumor recurrence or metastasis. Vaccines and antigens for anticancer therapy are discussed in this review, including current vaccine adjuvants and mechanisms of action for various types of vaccines, such as DNA- or mRNA-based cancer vaccines. Potential applications of these vaccines focusing on their clinical use for better therapeutic efficacy are also discussed along with the latest research available in this field.

Cervical Microbiome in Women Infected with HPV16 and High-Risk HPVs

Human papillomavirus type 16 (HPV16) and/or high-risk (Hr-) HPV are the main causes of cervical cancer. Another element that may contribute to the development of cervical cancer is the microbiota. To date, no study has investigated the entire cervical microbiome, which consists of bacteria, fungi, and viruses. In this study, cervical samples with different histopathology (CIN1, CIN2, and CIN3), with or without HPV16 and Hr-HPVs infection, were enrolled. From bacterial community analysis, 115 bacterial species were found and separated into 2 distinct categories based on Lactobacillus abundance: Lactobacilli-dominated (LD) and non-Lactobacilli-dominated (NLD) groups. The LD group had significantly less bacterial diversity than the NLD group. In addition, the variety of bacteria was contingent on the prevalence of HPV infection. Among distinct histological groups, an abundance of L. iners (>60% of total Lactobacillus spp.) was discovered in both groups. A few fungi, e.g., C. albicans, were identified in the fungal community. The viral community analysis revealed that the presence of HPV considerably reduced the diversity of human viruses. Taken together, when we analyzed all our results collectively, we discovered that HPV infection was a significant determinant in the diversity of bacteria and human viruses in the cervix.

Multidrug Resistance in Cancer: Understanding Molecular Mechanisms, Immunoprevention and Therapeutic Approaches

Cancer is one of the leading causes of death worldwide. Several treatments are available for cancer treatment, but many treatment methods are ineffective against multidrug-resistant cancer. Multidrug resistance (MDR) represents a major obstacle to effective therapeutic interventions against cancer. This review describes the known MDR mechanisms in cancer cells and discusses ongoing laboratory approaches and novel therapeutic strategies that aim to inhibit, circumvent, or reverse MDR development in various cancer types. In this review, we discuss both intrinsic and acquired drug resistance, in addition to highlighting hypoxia- and autophagy-mediated drug resistance mechanisms. Several factors, including individual genetic differences, such as mutations, altered epigenetics, enhanced drug efflux, cell death inhibition, and various other molecular and cellular mechanisms, are responsible for the development of resistance against anticancer agents. Drug resistance can also depend on cellular autophagic and hypoxic status. The expression of drug-resistant genes and the regulatory mechanisms that determine drug resistance are also discussed. Methods to circumvent MDR, including immunoprevention, the use of microparticles and nanomedicine might result in better strategies for fighting cancer.

The vaginal microbiome: A complex milieu affecting risk of human papillomavirus persistence and cervical cancer

The purpose of this review is to describe the existing literature regarding the relationship between the vaginal microbiome, human papillomavirus persistence, and cervical cancer risk, as well as to discuss factors that mediate these relationships. Data suggest that alterations in the vaginal microbiome affect the risk of human papillomavirus infection and persistence, which has downstream effects on cervical dysplasia and cancer risk. The homeostatic Lactobillus species L. crispatus, L. gasseri, L. jensenii act to promote a healthy vaginal environment, while L. iners and pathogens causing bacterial vaginosis are associated with increased inflammation, human papillomavirus infection, cervical dysplasia, and potentially cancer. There are, however, still several large gaps in the literature, particularly related to the modifiable and non-modifiable factors that affect the vaginal microbiome and ensuing risk of pre-cancerous and cancerous lesions. Evidence currently suggests that endogenous and exogenous hormones, tobacco products, and sexual practices influence vaginal microbiome composition, but the nuances of these relationships and how changes in these factors affect dysplasia risk are yet to be delineated. Other studies examining how diet, exercise, race, socioeconomic status, and genetic factors influence the vaginal microbiome are difficult to interpret in the setting of multiple confounders. Future studies should focus on how changes in these modulatory factors might promote a healthy vaginal microbiome to prevent or treat dysplasia in the lower female genital tract.

Immune responses of patients without cancer recurrence after a cancer vaccine over a long term

The present study aimed to clarify the humoral and cellular immune responses of patients with cancer who experienced no recurrence over a long term after receiving a cancer vaccine. The immune kinetics were investigated in response to a personalized peptide vaccination (PPV) among 44 Japanese patients without an active tumor at entry to the vaccination: Lung adenocarcinoma (n=11); colon (n=18); and breast cancer (n=15) (9, 10, 12, 8 and 5 patients with stage I, II, III and IV recurrences, respectively). The patients' immunoglobulin G (IgG) and cytotoxic T lymphocyte (CTL) activities were measured using a multiplexed Luminex assay and an interferon-γ release assay, respectively. There were no severe adverse events related to the PPV other than a grade III injection site reaction. A potent boost in IgG or CTL at the end of the 1st vaccination cycle was observed in 77% of the patients (n=84). The IgG levels were sustained throughout the follow-up period, whereas the CTL levels declined and were transient. A total of 37 of the 44 patients (84%) had no recurrence, with a median follow-up of 67.6 months (interquartile range, 45.6-82.8 months). Overall, the PPV induced long-term humoral immunity with transient cellular immunity in the majority of patients with cancer without an active tumor at their entry to the PPV.

B Cell Responses upon Human Papillomavirus (HPV) Infection and Vaccination

Infection with human papillomavirus (HPV) is the necessary cause of cervical cancer. Availability of vaccines against HPV makes it a highly preventable disease. HPV vaccines act through type-specific neutralizing antibodies produced by antigen-specific plasma cells known as long-lived plasma cells (LLPC). However, just as any other vaccine, success of HPV vaccine is attributed to the immunologic memory that it builds, which is largely attained through generation and maintenance of a class of B cells named memory B cells (Bmem). Both LLPCs and Bmems are important in inducing and maintaining immune memory and it is therefore necessary to understand their role after HPV vaccination to better predict outcomes. This review summarizes current knowledge of B-cell responses following HPV vaccination and natural infection, including molecular signatures associated with these responses.

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

BACKGROUND AND OBJECTIVES

In 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.

METHODS

A 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.

RESULTS

All 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.

CONCLUSIONS

The 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.

Socioeconomic disadvantage and human papillomavirus (HPV) vaccination uptake

IMPORTANCE

Despite availability of safe and effective human papillomavirus (HPV) vaccines, vaccination uptake remains low in the U.S. Research examining the impact of neighborhood socioeconomic status on HPV vaccination may help target interventions.

OBJECTIVE

To examine the association between area deprivation and HPV vaccine initiation and completion.

DESIGN, SETTING, PARTICIPANTS

Retrospective cohort study of individuals aged 11-18 years residing in the upper Midwest region. Receipt of HPV vaccination was examined over a three-year follow-up period (01/01/2016-12/31/2018).

MAIN OUTCOMES AND MEASURES

Outcomes of interest were initiation and completion of HPV vaccination. Demographic data were collected from the Rochester Epidemiology Project (REP). Area-level socioeconomic disadvantage was measured by calculating an Area Deprivation Index (ADI) score for each person, a measure of socioeconomic disadvantage derived from American Community Survey data. Multivariable mixed effect Cox proportional hazards models were used to examine the association of ADI quartiles (Q1-Q4) with HPV vaccine series initiation and completion, given initiation.

RESULTS

Individuals residing in census block groups with higher deprivation had significantly lower likelihood of HPV vaccine initiation (Q2: HR = 0.91, 0.84-0.99 Q3: HR = 0.83, 0.76-0.90; Q4: HR = 0.84, 0.74-0.96) relative to those in the least-deprived block groups (Q1). Similarly, those living in block groups with higher deprivation had significantly lower likelihood of completion (Q2: HR = 0.91, 0.86-0.97; Q3: HR = 0.87, 0.81-0.94; Q4: HR = 0.82, 0.74-0.92) compared to individuals in the least-deprived block groups (Q1).

CONCLUSIONS AND RELEVANCE

Lower probability of both HPV vaccine-series initiation and completion were observed in areas with greater deprivation. Our results can inform allocation of resources to increase HPV vaccination rates in our primary care practice and provide an example of leveraging public data to inform similar efforts across diverse health systems.

Developments in Vaccine Adjuvants

Vaccines, including subunit, recombinant, and conjugate vaccines, require the use of an immunostimulator/adjuvant for maximum efficacy. Adjuvants not only enhance the strength and longevity of immune responses but may also influence the type of response. In this chapter, we review the adjuvants that are available for use in human vaccines, such as alum, MF59, AS03, and AS01. We extensively discuss their composition, characteristics, mechanism of action, and effects on the immune system. Additionally, we summarize recent trends in adjuvant discovery, providing a brief overview of saponins, TLRs agonists, polysaccharides, nanoparticles, cytokines, and mucosal adjuvants.

Mechanisms of cellular and humoral immunity through the lens of VLP-based vaccines

INTRODUCTION

Vaccination can be effective defense against many infectious agents and the corresponding diseases. Discoveries elucidating the mechanisms of the immune system have given hopes to developing vaccines against diseases recalcitrant to current treatment/prevention strategies. One such finding is the ability of immunogenic biological nanoparticles to powerfully boost the immunogenicity of poorer antigens conjugated to them with virus-like particle (VLP)-based vaccines as a key example. VLPs take advantage of the well-defined molecular structures associated with sub-unit vaccines and the immunostimulatory nature of conjugate vaccines.

AREAS COVERED

In this review, we will discuss how advances in understanding the immune system can inform VLP-based vaccine design and how VLP-based vaccines have uncovered underlying mechanisms in the immune system.

EXPERT OPINION

As our understanding of mechanisms underlying the immune system increases, that knowledge should inform our vaccine design. Testing of proof-of-concept vaccines in the lab should seek to elucidate the underlying mechanisms of immune responses. The integration of these approaches will allow for VLP-based vaccines to live up to their promise as a powerful plug-and-play platform for next generation vaccine development.

Human papillomavirus antibody levels following vaccination or natural infection among young men who have sex with men

BACKGROUND

Australia introduced a school-based gender-neutral human papillomavirus (HPV) vaccination program for schoolgirls and boys aged 12-13 years in 2013. We examined HPV type specific antibody levels in unvaccinated young men who have sex with men (MSM) with natural infection and compared these to levels in those vaccinated against HPV.

METHODS

Serum specimens at baseline were collected from MSM aged 16-20 years in the HYPER1 and HYPER2 studies, conducted between 2010-2013 and 2017-2019, respectively. Merck's 4-plex HPV competitive Luminex Immunoassay was used to quantify HPV6, 11, 16 and 18 specific antibodies. We compared antibody levels for each HPV genotype between unvaccinated men (HYPER1) and vaccinated men (HYPER2) using the Mann-Whitney U test.

RESULTS

There were 200 unvaccinated men and 127 vaccinated men included in the analysis. Median antibody levels among vaccinated men were significantly higher than levels among unvaccinated men for HPV6 (223 mMU/ml vs 48 mMU/ml, p<0.0001), HPV11 (163 mMU/ml vs 21 mMU/ml, p<0.0001), HPV16 (888 mMU/ml vs 72 mMU/ml, p<0.0001) and HPV18 (161 mMU/ml vs 20 mMU/ml, p<0.0001). The median time between antibody level measurement and last vaccine dose was 47.7 (IQR 40.4 to 54.1) months. Antibody levels did not change over time for up to 66 months for all four genotypes among vaccinated men.

CONCLUSION

Among young MSM vaccinated with the quadrivalent HPV vaccine, antibody levels for HPV 6, 11, 16 and 18 were significantly higher than those in unvaccinated MSM following natural infection. Antibody levels following vaccination appeared to remain stable over time.

HPV-mediated Cervical Cancer: A Systematic review on Immunological Basis, Molecular Biology and Immune evasion mechanisms

BACKGROUND

Human papillomavirus (HPV), one of the most frequently transmitted viruses globally, causing several malignancies including cervical cancer.

AIM

Owing to their unique pathogenicity HPV viruses can persist in the host organism for a longer duration than other virus types, to complete their lifecycle. During its association with the host, HPV causes various pathological conditions affecting the immune system by evading the host immune- mechanisms leading to the progression of various diseases, including cancer.

METHOD

To date, ~ 150 serotypes were identified, and certain high-risk HPV types are known to be associated with genital warts and cervical cancer. As of now, two prophylactic vaccines are in use for the treatment of HPV infection, however, no effective antiviral drug is available for HPV-associated disease/infections. Numerous clinical and laboratory studies are being investigated to formulate an effective and specific vaccine again HPV infections and associated diseases.

RESULT

As the immunological basis of HPV infection and associated disease progress persist indistinctly, deeper insights on immune evasion mechanism and molecular biology of disease would aid in developing an effective vaccine.

CONCLUSION

Thus this review focuses, aiming a systematic review on the immunological aspects of HPV-associated cervical cancer by uncovering immune evasion strategies adapted by HPV.

VLP-Based COVID-19 Vaccines: An Adaptable Technology against the Threat of New Variants

Virus-like particles (VLPs) are a versatile, safe, and highly immunogenic vaccine platform. Recently, there are developmental vaccines targeting SARS-CoV-2, the causative agent of COVID-19. The COVID-19 pandemic affected humanity worldwide, bringing out incomputable human and financial losses. The race for better, more efficacious vaccines is happening almost simultaneously as the virus increasingly produces variants of concern (VOCs). The VOCs Alpha, Beta, Gamma, and Delta share common mutations mainly in the spike receptor-binding domain (RBD), demonstrating convergent evolution, associated with increased transmissibility and immune evasion. Thus, the identification and understanding of these mutations is crucial for the production of new, optimized vaccines. The use of a very flexible vaccine platform in COVID-19 vaccine development is an important feature that cannot be ignored. Incorporating the spike protein and its variations into VLP vaccines is a desirable strategy as the morphology and size of VLPs allows for better presentation of several different antigens. Furthermore, VLPs elicit robust humoral and cellular immune responses, which are safe, and have been studied not only against SARS-CoV-2 but against other coronaviruses as well. Here, we describe the recent advances and improvements in vaccine development using VLP technology.

Current and Emerging Molecular Therapies for Head and Neck Squamous Cell Carcinoma

Head and neck cancer affects nearly 750,000 patients, with more than 300,000 deaths annually. Advances in first line surgical treatment have improved survival rates marginally particularly in developed countries, however survival rates for aggressive locally advanced head and neck cancer are still poor. Recurrent and metastatic disease remains a significant problem for patients and the health system. As our knowledge of the genomic landscape of the head and neck cancers continues to expand, there are promising developments occurring in molecular therapies available for advanced or recalcitrant disease. The concept of precision medicine is underpinned by our ability to accurately sequence tumour samples to best understand individual patient genomic variations and to tailor targeted therapy for them based on such molecular profiling. Not only is their purported response to therapy a factor of their genomic variation, but so is their inclusion in biomarker-driven personalised medicine therapeutic trials. With the ever-expanding number of molecular druggable targets explored through advances in next generation sequencing, the number of clinical trials assessing these targets has significantly increased over recent years. Although some trials are focussed on first-line therapeutic approaches, a greater majority are focussed on locally advanced, recurrent or metastatic disease. Similarly, although single agent monotherapy has been found effective in some cases, it is the combination of drugs targeting different signalling pathways that seem to be more beneficial to patients. This paper outlines current and emerging molecular therapies for head and neck cancer, and updates readers on outcomes of the most pertinent clinical trials in this area while also summarising ongoing efforts to bring more molecular therapies into clinical practice.

Exploration of Pattern Recognition Receptor Agonists as Candidate Adjuvants

Adjuvants are used to maximize the potency of vaccines by enhancing immune reactions. Components of adjuvants include pathogen-associated molecular patterns (PAMPs) and damage-associate molecular patterns (DAMPs) that are agonists for innate immune receptors. Innate immune responses are usually activated when pathogen recognition receptors (PRRs) recognize PAMPs derived from invading pathogens or DAMPs released by host cells upon tissue damage. Activation of innate immunity by PRR agonists in adjuvants activates acquired immune responses, which is crucial to enhance immune reactions against the targeted pathogen. For example, agonists for Toll-like receptors have yielded promising results as adjuvants, which target PRR as adjuvant candidates. However, a comprehensive understanding of the type of immunological reaction against agonists for PRRs is essential to ensure the safety and reliability of vaccine adjuvants. This review provides an overview of the current progress in development of PRR agonists as vaccine adjuvants, the molecular mechanisms that underlie activation of immune responses, and the enhancement of vaccine efficacy by these potential adjuvant candidates.

Practice and Associated Factors of Human Papillomavirus Vaccination Among Primary School Students in Minjar-Shenkora District, North Shoa Zone, Amhara Regional State, Ethiopia, 2020

Background

Human papillomavirus infection, a causative factor for cervical cancer, remains a topic of great interest. About 80% of sexually active women are at risk of acquiring HPV infection while having a 70% global target to eliminate intensive cervical cancer.

Objective

This study aimed to assess the practice of human papillomavirus vaccination and associated factors among primary school female students in Minjar-Shenkora district, 2020.

Methods

A school-based quantitative cross-sectional study was conducted from February 1 to 30 2020, in primary school female students of Minjar-Shenkora district, North Shoa zone, Ethiopia. A structured self-administered questionnaire was used for data collection. Associations between dependent and independent variables tested in binary and multiple logistic regression and variables with p-value ≤0.25 were entered into multiple logistic regression with considered significant level of P-value ≤0.05 and at 95% confidence interval (CI).

Results

A total of 591 students participated in the study with a response rate of 96.3%. Of the total, 393 (66.5%) (CI 0.63–0.7) participants have been vaccinated for HPV. The factors associated with the practice of vaccination were; being knowledgeable about HPV vaccination (AOR, 8.65, CI=5.2–14.3) and a positive attitude towards HPV vaccination (AOR, 1.85, CI=1.18–3). Students in rural areas were 88% less likely to practice HPV vaccine than students in urban areas (AOR, 0.12, CI=0.07 0.21).

Conclusion and Recommendation

Overall, HPV vaccination practice was relatively good (66.5%). Knowledge on HPV vaccination, positive attitude towards HPV vaccination, and being a rural residence were associated with HPV vaccination practice. Families, health-care workers, and schools should work together to improve the knowledge and attitude of the community towards HPV vaccination.

Case Report: Noninvasive Clinical Intervention of REBACIN® on Histologic Regression of High Grade Cervical Intraepithelial Neoplasia

High-risk human papillomavirus (hrHPV) persistent infection is the major cause of cervical cancer. Clinical intervention of hrHPV-associated high-grade squamous intraepithelial lesion (HSIL) is critical to prevent cervical cancer, and current treatment is surgery (an invasive therapy). However, some patients refuse to do so for an afraid of potential adverse effects on future fertility or other concerns which creates a critical need for development of non-invasive therapeutic strategies. Here, we report for the first time the cases of non-invasive intervention with REBACIN®, a proprietary antiviral biologics, in clinical treatment of HSIL. From 12,958 visiting patients assessed for eligibility, 18 HSIL-patients with cervical intraepithelial neoplasia-grade 2, positive of both diffused overexpression of p16 and high-risk HPV were enrolled in this non-invasive clinical intervention mainly due to concerns of future fertility. REBACIN® was administered intravaginally every other day for 3 months (one-course) except during menstrual period, and were followed up for 6-36 months for the examination of high-risk HPV DNA, cervical cytology, and histopathology. After one to three course treatments, most cases (16/18) displayed both the regression from HSIL (CIN2) to normal cervical cytology and clearance of high-risk HPV infection. Further studies demonstrated REBACIN® significantly suppressed HPV16 E7 oncoprotein expression in a human cervical cancer cell line, which is consistent with previous finding that REBACIN® inhibits the growth of tumors induced by expression of E6/E7 oncogenes of either HPV16 or HPV18. This report indicates REBACIN® as a novel effective non-invasive clinical intervention for HSIL-patients as well for high-risk HPV persistent infection, providing a new clinical option for the non-invasive treatment of hrHPV-associated high-grade squamous intraepithelial lesion, which is worthy of further research on clinical validation and application.

Male Circumcision Reduces Penile HPV Incidence and Persistence: A Randomized Controlled Trial in Kenya

BACKGROUND

Male circumcision reduces the risk of human immunodeficiency virus infection in men. We assessed the effect of male circumcision on the incidence and natural history of human papillomavirus (HPV) in a randomized clinical trial in Kisumu, Kenya.

METHODS

Sexually active, 18- to 24-year-old men provided penile exfoliated cells for HPV DNA testing every 6 months for 2 years. HPV DNA was detected via GP5+/6+ PCR in glans/coronal sulcus and in shaft samples. HPV incidence and persistence were assessed by intent-to-treat analyses.

RESULTS

A total of 2,193 men participated (1,096 randomized to circumcision; 1,097 controls). HPV prevalence was 50% at baseline for both groups and dropped to 23.7% at 24 months in the circumcision group, and 41.0% in control group. Incident infection of any HPV type over 24 months was lower among men in the circumcision group than in the control group [HR = 0.61; 95% confidence interval (CI), 0.52-0.72]. Clearance rate of any HPV infection over 24 months was higher in the circumcision group than in the control group (HR = 1.87; 95% CI, 1.49-2.34). Lower HPV point-prevalence, lower HPV incidence, and higher HPV clearance in the circumcision group were observed in glans but not in shaft samples.

CONCLUSION

Male circumcision reduced the risk of HPV acquisition and reinfection, and increased HPV clearance in the glans.

IMPACT

Providing voluntary, safe, and affordable male circumcision should help reduce HPV infections in men, and consequently, HPV-associated disease in their partners.

High prevalence of anal high-grade squamous intraepithelial lesions, and prevention through human papillomavirus vaccination, in young men who have sex with men living with HIV

Background

Men who have sex with men (MSM) are at high risk for human papillomavirus (HPV)–related anal cancer. Little is known about the prevalence of low-grade squamous intraepithelial lesions (LSILs) and the anal cancer precursor, high-grade squamous intraepithelial lesions (HSILs), among young MSM with HIV (MSMLWH). HPV vaccination is recommended in this group, but its safety, immunogenicity, and protection against vaccine-type HPV infection and associated LSILs/HSILs have not been studied.

Methods

Two hundred and sixty MSMLWH aged 18–26 years were screened at 17 US sites for a clinical trial of the quadrivalent (HPV6,11,16,18) HPV (qHPV) vaccine. Those without HSILs were vaccinated at 0, 2, and 6 months. Cytology, high-resolution anoscopy with biopsies of lesions, serology, and HPV testing of the mouth/penis/scrotum/anus/perianus were performed at screening/month 0 and months 7, 12, and 24.

Results

Among 260 MSMLWH screened, the most common reason for exclusion was detection of HSILs in 88/260 (34%). 144 MSMLWH were enrolled. 47% of enrollees were previously exposed to HPV16. No incident qHPV type–associated anal LSILs/HSILs were detected among men naive to that type, compared with 11.1, 2.2, 4.5, and 2.8 cases/100 person-years for HPV6,11,16,18–associated LSILs/HSILs, respectively, among those previously exposed to that type. qHPV was immunogenic and safe with no vaccine-associated serious adverse events.

Conclusions

18–26-year-old MSMLWH naive to qHPV vaccine types were protected against incident qHPV type–associated LSILs/HSILs. Given their high prevalence of HSILs, there is an urgent need to vaccinate young MSMLWH before exposure to vaccine HPV types, before initiating sexual activity, and to perform catch-up vaccination.

The Immune Microenvironment in Human Papilloma Virus-Induced Cervical Lesions-Evidence for Estrogen as an Immunomodulator

Globally, human papilloma virus (HPV) infection is a common sexually transmitted disease. However, most of the HPV infections eventually resolve aided by the body’s efficient cell-mediated immune responses. In the vast majority of the small group of patients who develop overt disease too, it is the immune response that culminates in regression of lesions. It is therefore a rarity that persistent infection by high-risk genotypes of HPV compounded by other risk factors progresses through precancer (various grades of cervical intraepithelial neoplasia—CIN) to cervical cancer (CxCa). Hence, although CxCa is a rare culmination of HPV infection, the latter is nevertheless causally linked to >90% of cancer. The three ‘Es’ of cancer immunoediting viz. elimination, equilibrium, and escape come into vogue during the gradual evolution of CIN 1 to CxCa. Both cell-intrinsic and extrinsic mechanisms operate to eliminate virally infected cells: cell-extrinsic players are anti-tumor/antiviral effectors like Th1 subset of CD4+ T cells, CD8+ cytotoxic T cells, Natural Killer cells, etc. and pro-tumorigenic/immunosuppressive cells like regulatory T cells (Tregs), Myeloid-Derived Suppressor Cells (MDSCs), type 2 macrophages, etc. And accordingly, when immunosuppressive cells overpower the effectors e.g., in high-grade lesions like CIN 2 or 3, the scale is tilted towards immune escape and the disease progresses to cancer. Estradiol has long been considered as a co-factor in cervical carcinogenesis. In addition to the gonads, the Peyer’s patches in the gut synthesize estradiol. Over and above local production of the hormone in the tissues, estradiol metabolism by the gut microbiome: estrobolome versus tryptophan non-metabolizing microbiome, regulates free estradiol levels in the intestine and extraintestinal mucosal sites. Elevated tissue levels of the hormone serve more than one purpose: besides a direct growth-promoting action on cervical epithelial cells, estradiol acting genomically via Estrogen Receptor-α also boosts the function of the stromal and infiltrating immunosuppressive cells viz. Tregs, MDSCs, and carcinoma-associated fibroblasts. Hence as a corollary, therapeutic repurposing of Selective Estrogen Receptor Disruptors or aromatase inhibitors could be useful for modulating immune function in cervical precancer/cancer. The immunomodulatory role of estradiol in HPV-mediated cervical lesions is reviewed.

To Include or Occlude: Rational Engineering of HCV Vaccines for Humoral Immunity

Direct-acting antiviral agents have proven highly effective at treating existing hepatitis C infections but despite their availability most countries will not reach the World Health Organization targets for elimination of HCV by 2030. A prophylactic vaccine remains a high priority. Whilst early vaccines focused largely on generating T cell immunity, attention is now aimed at vaccines that generate humoral immunity, either alone or in combination with T cell-based vaccines. High-resolution structures of hepatitis C viral glycoproteins and their interaction with monoclonal antibodies isolated from both cleared and chronically infected people, together with advances in vaccine technologies, provide new avenues for vaccine development.

Immunogenicity of 2 and 3 Doses of the Quadrivalent Human Papillomavirus Vaccine up to 120 Months Postvaccination: Follow-up of a Randomized Clinical Trial

Background

Several countries have implemented a 2-dose (2D) human papillomavirus (HPV) vaccination schedule for adolescents based on immunobridging studies. We compared immunogenicity of 2D vs 3-dose (3D) schedules of the quadrivalent vaccine (4vHPV) up to 10 years after the first dose.

Methods

Girls aged 9–13 years were randomized to receive 2D or 3D and were compared with women aged 16–26 receiving 3D at day 1 and months 7, 24, and 120 after the first dose. Antibody levels for HPV6/11/16/18 were evaluated using the competitive Luminex immunoassay (cLIA) and total immunoglobulin G assay. Geometric mean titers (GMTs) and seropositivity rates were compared between the different groups at different time points. Noninferiority of GMT ratios was defined as the lower bound of the 2-sided 95% confidence interval (CI) being greater than 0.5. Kinetics of antibody titers over time among study groups were examined.

Results

At 120 months, data from 35 2D girls, 38 3D girls, and 30 3D women were used for analyses. cLIA seropositivity rates were above 95% for all HPV vaccine types and all schedules, except HPV18, with the lowest seropositivity observed among 3D women (60.0%; 95% CI, 40.6%–77.3%). GMT ratios (cLIA) for both 2D and 3D girls were noninferior to 3 doses in women for HPV6/11/16/18. Trends were comparable between assays.

Conclusions

GMTs for HPV6/11/16/18 after 2D or 3D of 4vHPV in girls were noninferior to 3D in adult women up to 120 months postvaccination. This study demonstrates long-term immunogenicity of the 2D HPV vaccine schedule.

Respective prevalence of high-risk HPVgenotypes in cervical neoplasia in Senegal

OBJECTIVES

With the perspective of prophylactic vaccination against high-risk human papillomavirus (HPV), we analyzed the viral epidemiology of cervical neoplasia in Senegal.

METHODS

All patients were treated at the Institut Joliot Curie du Cancer in Dakar. HPV genotypes were characterized using a real-time polymerase chain reaction-based approach and sequencing.

RESULTS

Histologically, there were 224 invasive carcinomas, 17 high-grade intraepithelial neoplasia (CIN), and five undetermined histologies. Molecular analysis was conclusive in 241 cases. HPV DNA was found in 207/241 (85.9%) cases while 34/241 (14.1%) remained HPV negative. There was one single genotype in 127/207 (61.4%) cases and several in 80/207 (38.6%) corresponding to 308 genotypes identified. Viral genotyping found HPV16 in 175 (56.8%) cases, HPV18 in 45 (14.6%), HPV45 in 40 (13.0%), HPV58 in 35 (11.4%), HPV33 in 6 (2.0%), HPV35 in 3 (1.0%), HPV31 in 2 (0.6%), HPV39 and HPV56 in one (0.3% each).

CONCLUSION

Our analysis showed that 98.4% of the HPV-positive cases were associated with viral genotypes covered by the 9-valent HPV vaccine. However, 14.1% of cases remained HPV negative. Therefore, prophylactic vaccination using a 9-valent vaccine should dramatically reduce the incidence of HPV-associated neoplasia but the detection and treatment of CIN remain necessary for the optimal prevention of cervical cancer.

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.

Cancer Vaccines: Adjuvant Potency, Importance of Age, Lifestyle, and Treatments

Although the discovery and characterization of multiple tumor antigens have sparked the development of many antigen/derived cancer vaccines, many are poorly immunogenic and thus, lack clinical efficacy. Adjuvants are therefore incorporated into vaccine formulations to trigger strong and long-lasting immune responses. Adjuvants have generally been classified into two categories: those that ‘depot’ antigens (e.g. mineral salts such as aluminum hydroxide, emulsions, liposomes) and those that act as immunostimulants (Toll Like Receptor agonists, saponins, cytokines). In addition, several novel technologies using vector-based delivery of antigens have been used. Unfortunately, the immune system declines with age, a phenomenon known as immunosenescence, and this is characterized by functional changes in both innate and adaptive cellular immunity systems as well as in lymph node architecture. While many of the immune functions decline over time, others paradoxically increase. Indeed, aging is known to be associated with a low level of chronic inflammation—inflamm-aging. Given that the median age of cancer diagnosis is 66 years and that immunotherapeutic interventions such as cancer vaccines are currently given in combination with or after other forms of treatments which themselves have immune-modulating potential such as surgery, chemotherapy and radiotherapy, the choice of adjuvants requires careful consideration in order to achieve the maximum immune response in a compromised environment. In addition, more clinical trials need to be performed to carefully assess how less conventional form of immune adjuvants, such as exercise, diet and psychological care which have all be shown to influence immune responses can be incorporated to improve the efficacy of cancer vaccines. In this review, adjuvants will be discussed with respect to the above-mentioned important elements.

Trial watch: FDA-approved Toll-like receptor agonists for cancer therapy

Toll-like receptors (TLRs) have first been characterized for their capacity to detect conserved microbial components like lipopolysaccharide (LPS) and double-stranded RNA, resulting in the elicitation of potent (innate) immune responses against invading pathogens. More recently, TLRs have also been shown to promote the activation of the cognate immune system against cancer cells. Today, only three TLR agonists are approved by FDA for use in humans: the bacillus Calmette-Guérin (BCG), monophosphoryl lipid A (MPL) and imiquimod. BCG (an attenuated strain of Mycobacterium bovis) is mainly used as a vaccine against tuberculosis, but also for the immunotherapy of in situ bladder carcinoma. MPL (derived from the LPS of Salmonella minnesota) is included in the formulation of Cervarix®, a vaccine against human papillomavirus-16 and -18. Imiquimod (a synthetic imidazoquinoline) is routinely employed for actinic keratosis, superficial basal cell carcinoma, and external genital warts (condylomata acuminata). In this Trial Watch, we will summarize the results of recently completed clinical trials and discuss the progress of ongoing studies that have evaluated/are evaluating FDA-approved TLR agonists as off-label medications for cancer therapy.