HPV vaccination among seropositive, DNA negative cohorts: a systematic review & meta-analysis

Estimating the Age of Disease-causal HPV Infection Based on the Natural History of CIN2+ Among Females in Canada

Background

Although human papillomavirus (HPV) vaccination is approved for males and females up to 45 years of age in Canada, not all of the jurisdictions offer catch-up programs up to age 26. However, US-based modeling studies suggest a significant proportion of causal HPV infections leading to high-grade cervical intraepithelial neoplasia (CIN+) and cervical cancer occur in women older than age 26 years. To inform vaccination policies in Canada, this study estimated the age distribution of putatively causal HPV infections leading to CIN2+ based on the natural history.

Methods

We modified an existing discrete event simulation model to estimate the age of causal HPV infection for females diagnosed with CIN2+. Simulated females (n = 1000) were tracked through 3 stages while undergoing screening: causal HPV infection, CIN2+ disease onset, and diagnosis. We identified the age distribution for causal infections that best fit the observed age distribution for CIN2+ diagnosis. Ten independent model runs were conducted to assess reproducibility.

Results

The predicted median age at causal HPV infection and CIN2+ diagnosis in Canada was 24.9 (95% confidence interval, 24.3-26.1) and 29.8 years (95% confidence interval, 28.8-30.6), respectively. The model estimated that 84.1% and 47.1% of causal HPV infections occurred in women older than age 18 and 26 years, respectively. Results were stable across 10 model runs.

Conclusions

The analysis indicates a substantial percentage of causal HPV infections for CIN2+ occur among women aged 26 years or older. Extending catch-up vaccination programs to women above age 26 years should be considered to prevent these infections and reduce HPV-related cervical diseases.

Advancing the Fight Against Cervical Cancer: The Promise of Therapeutic HPV Vaccines

Human papillomavirus (HPV) is a major global health issue and is recognized as the leading cause of cervical cancer. While prophylactic vaccination programs have led to substantial reductions in both HPV infection rates and cervical cancer incidence, considerable burdens of HPV-related diseases persist, particularly in developing countries with inadequate vaccine coverage and uptake. The development of therapeutic vaccines for HPV represents an emerging strategy that has the potential to bolster the fight against cervical cancer. Unlike current prophylactic vaccines designed to prevent new infections, therapeutic vaccines aim to eradicate or treat existing HPV infections, as well as HPV-associated precancers and cancers. This review focuses on clinical studies involving therapeutic HPV vaccines for cervical cancer, specifically in three key areas: the treatment of cervical intraepithelial neoplasia; the treatment of cervical cancer in combination with or without chemotherapy, radiotherapy, or immune checkpoint inhibitors; and the role of prophylaxis following completion of treatment. Currently, there are no approved therapeutic HPV vaccines worldwide; however, active progress is being made in clinical research and development using multiple platforms such as peptides, proteins, DNA, RNA, bacterial vectors, viral vectors, and cell-based, each offering relative advantages and limitations for delivering HPV antigens and generating targeted immune responses. We outline preferred vaccine parameters, including indications, target populations, safety considerations, efficacy considerations, and immunization strategies. Lastly, we emphasize that therapeutic vaccines for HPV that are currently under development could be an important new tool in fighting against cervical cancer.

The 13-year long-term follow-up on the effectiveness and immunogenicity of the quadrivalent human papillomavirus vaccine in Chinese females vaccinated at 20-45 years of age

TRIAL REGISTRATION

The LTFU study was registered at the Chinese Clinical Trial Registry, ChiCTR2100052313.

Comprehensive insights into human papillomavirus and cervical cancer: Pathophysiology, screening, and vaccination strategies

This article provides an in-depth review of the Human Papillomavirus (HPV), a predominant etiological factor in cervical cancer, exploring its pathophysiology, epidemiology, and mechanisms of oncogenesis. We examine the role of proteins, DNA methylation markers, and non-coding RNAs as predictive biomarkers in cervical cancer, highlighting their potential in refining diagnostic and prognostic practices. The evolution and efficacy of cervical cancer screening methods, including the Papanicolaou smear, HPV testing, cytology and HPV test, and colposcopy techniques, are critically analyzed. Furthermore, the article delves into the current landscape and future prospects of prophylactic HPV vaccines and therapeutic vaccines, underscoring their significance in the prevention and potential treatment of HPV-related diseases. This comprehensive review aims to synthesize recent advances and ongoing challenges in the field, providing a foundation for future research and clinical strategies in the prevention and management of cervical cancer.

Efficacy and immunogenicity of AS04-HPV-16/18 vaccine in females with existing cervical HR-HPV infection at first vaccination: A pooled analysis of four large clinical trials worldwide

Females with existing high-risk HPV (HR-HPV) infections remain at risk of subsequent multiple or recurrent infections, on which benefit from HPV vaccines was under-reported. We pooled individual-level data from four large-scale, RCTs of AS04-HPV-16/18 vaccine to evaluate efficacy and immunogenicity in females DNA-positive to any HR-HPV types at first vaccination. Females receiving the AS04-HPV-16/18 vaccine in the original RCTs constituted the vaccine group in the present study, while those unvaccinated served as the control group. Vaccine efficacy (VE) against new infections and associated cervical intraepithelial neoplasia (CIN) 2+ in females DNA-negative to the considered HR-HPV type but positive to any other HR-HPV types, VE against reinfections in females DNA-positive to the considered HR-HPV type but cleared naturally during later follow-up, and levels of anti-HPV-16/18 IgG were assessed. Our final analyses included 5137 females (vaccine group = 2532, control group = 2605). The median follow-up time was 47.88 months (IQR: 45.72-50.04). For the prevention of precancerous lesions related to the non-infected HR-HPV types at baseline, VE against HPV-16/18 related CIN 2+ was 82.70% (95% CI: 63.70-93.00%). For the prevention of reinfections related to the infected HR-HPV types following natural clearance, VE against HPV-16/18 12MPI was non-significant (p > .05), albeit robust immunity persisted for at least 48 months. Females with existing HR-HPV infections at first vaccination still benefit from vaccination in preventing precancers related to the non-infected types at baseline. VE against reinfections related to the infected types following natural clearance remains to be further investigated.

Cervical cancer: Part I human papilloma virus vaccination in Taiwan

A significant decline in both incidence and prevalence of cervical cancers after widespread-introducing cervical screening strategy by Papanicolau test (Pap test) has been found in the world, but cervical cancer is still one of the most common female cancers, reporting the fourth prevalence and also one of the leading causes to result in main women-associated morbidity and mortality, particularly for those women living in low- and middle-income countries. Cervical cancer is one of the most important health concerns directly destroying the global health-care system, partly because of not only increasing the disability either secondary to diseases themselves of victims or mediated by treatment-related adverse events to the survivors but also acting as a leading cause of death of diseased patients worldwide, alarming the urgent need to do something to minimize the catastrophic diseases-related heavy socioeconomic burden. It is fortunate that cervical cancer is a preventable disease, based on its strong association with human papillomavirus (HPV) infection (more than 95%), particularly for those high-risk HPV (HR-HPV) and its high possibility by detecting HPV infection before the development of cervical cancer as well as an effective prevention by HPV vaccination. That is why WHO (World Health Organization) considers cervical cancer as a public problem and attempts to accelerate the elimination of cervical cancer program by three-pillar approach (90:70:90% targets), including (1) 90% of girls are fully vaccinated with HPV vaccine by 15 years of age; (2) 70% of women are screened with a high-performance test by 35 and 45 years of age and precancerous lesions are treated early; and (3) 90% of women identified with cervical diseases receive appropriate and adequate treatment. Herein, this review focuses on the HPV vaccination as Part I, including global recommendations and Taiwan government's policy for HPV vaccination.

Herpes Simplex Virus, Human Papillomavirus, and Cervical Cancer: Overview, Relationship, and Treatment Implications

There is a significant body of research examining the role of human papillomavirus (HPV) in the pathogenesis of cervical cancer, with a particular emphasis on the oncogenic proteins E5, E6, and E7. What is less well explored, however, is the relationship between cervical cancer and herpes simplex virus (HSV). To date, studies examining the role of HSV in cervical cancer pathogenesis have yielded mixed results. While several experiments have determined that HPV/HSV-2 coinfection results in a higher risk of developing cervical cancer, others have questioned the validity of this association. However, clarifying the potential role of HSV in the pathogenesis of cervical cancer may have significant implications for both the prevention and treatment of this disease. Should this relationship be clarified, treating and preventing HSV could open another avenue with which to prevent cervical cancer. The importance of this is highlighted by the fact that, despite the creation of an effective vaccine against HPV, cervical cancer still impacts 604,000 women and is responsible for 342,000 deaths annually. This review provides an overview of HSV and HPV infections and then delves into the possible links between HPV, HSV, and cervical cancer. It concludes with a summary of preventive measures against and recent treatment advances in cervical cancer.

Updates on HPV Vaccination

Cervical cancer still poses a significant global challenge. Developed countries have mitigated this challenge by the introduction of structured screening programmes and, more recently, the HPV vaccine. Countries that have successfully introduced national HPV vaccination programmes are on course for cervical cancer elimination in a few decades. In developing countries that lack structured screening and HPV vaccination programmes, cervical cancer remains a major cause of morbidity and mortality. The HPV vaccine is key to addressing the disproportionate distribution of cervical cancer incidence, with much to be gained from increasing vaccine coverage and uptake globally. This review covers the history and science of the HPV vaccine, its efficacy, effectiveness and safety, and some of the considerations and challenges posed to the achievement of global HPV vaccination coverage and the consequent elimination of cervical cancer.