Immunogenicity and safety of two novel human papillomavirus 4- and 9-valent vaccines in Chinese women aged 20-45 years: A randomized, blinded, controlled with Gardasil (type 6/11/16/18), phase III non-inferiority clinical trial

Opportunities and challenges for human papillomavirus vaccination in China

Current estimates of the HPV infection rate in China vary by geographic region (9.6-23.6%), with two age peaks in prevalence in women ≤20-25 years of age and 50-60 years of age. HPV-16, 52 and 58 are the most commonly-detected HPV genotypes in the Chinese population. In China, five HPV vaccines are licensed and several others are undergoing clinical trials. Multiple RCTs have shown the efficacy and safety of the bvHPV (Cervarix), Escherichia coli-produced bvHPV (Cecolin), Pichia pastoris-produced bvHPV (Walrinvax), qvHPV (Gardasil) and 9vHPV (Gardasil-9) vaccines in Chinese populations, including two studies showing long-term efficacy (≥8 years) for the bvHPV and qvHPV vaccines. Real-world data from China are scarce. Although modeling studies in China show HPV vaccination is cost-effective, uptake and population coverage are relatively low. Various policies have been implemented to raise awareness and increase vaccine coverage, with the long-term aim of eliminating cervical cancer in China.

Cancer vaccines: an update on recent achievements and prospects for cancer therapy

Decades of basic and translational research have led to a momentum shift in dissecting the relationship between immune cells and cancer. This culminated in the emergence of breakthrough immunotherapies that paved the way for oncologists to manage certain hard-to-treat cancers. The application of high-throughput techniques of genomics, transcriptomics, and proteomics was conclusive in making and expediting the manufacturing process of cancer vaccines. Using the latest research technologies has also enabled scientists to interpret complex and multiomics data of the tumour mutanome, thus identifying new tumour-specific antigens to design new generations of cancer vaccines with high specificity and long-term efficacy. Furthermore, combinatorial regimens of cancer vaccines with immune checkpoint inhibitors have offered new therapeutic approaches and demonstrated impressive efficacy in cancer patients over the last few years. In the present review, we summarize the current state of cancer vaccines, including their potential therapeutic effects and the limitations that hinder their effectiveness. We highlight the current efforts to mitigate these limitations and highlight ongoing clinical trials. Finally, a special focus will be given to the latest milestones expected to transform the landscape of cancer therapy and nurture hope among cancer patients.

The Non-inferiority of Human Papillomavirus Vaccine Immunogenicity Among Women Over 26 Years: A Systematic Review

OBJECTIVE

Demonstrate the immunogenicity of the human papillomavirus (HPV) vaccine for the older age group (above 26 years) to prevent HPV infection with high-risk types and argue for extending vaccination recommendations for the older age group.

METHODS

Two authors searched PubMed, Embase, and the Cochrane Library from inception to December 2023 to collect information on clinical trials of HPV vaccine immunogenicity. The database search strategy used a combination of subject terms and free terms. Two authors first identified studies by reading the title, abstract, and full texts and, subsequently, based on the inclusion criteria. Studies eligible to be included are the clinical trials using one of the following types of HPV vaccines: 2vHPV, 4vHPV, and 9vHPV, and measuring the immunogenicity by the geometric mean concentration or titer (GMC/T) and seroconversion rate (SCR) among healthy women aged 9 to 55 years who had never received a prophylactic HPV vaccine, known serostatus for HPV, non-immunocompetence, or non-pregnant.

RESULTS

This review included nine articles, seven RCTs, and two open-labeled studies.

CONCLUSION

In summary, we have demonstrated that the immunogenicity of the HPV vaccines is non-inferior in the older age group. Even though the GMT declines with age, the SCR is similar in all age groups regardless of the serostatus. The immunogenicity of the bivalent vaccine is superior to that of the quadrivalent vaccine for the older age group. Additionally, the vaccine is more efficient in women under the age of 26, but older women will benefit from it.

Current status and future directions for the development of human papillomavirus vaccines

The development of human papillomavirus (HPV) vaccines has made substantive progress, as represented by the approval of five prophylactic vaccines since 2006. Generally, the deployment of prophylactic HPV vaccines is effective in preventing newly acquired infections and incidences of HPV-related malignancies. However, there is still a long way to go regarding the prevention of all HPV infections and the eradication of established HPV infections, as well as the subsequent progression to cancer. Optimizing prophylactic HPV vaccines by incorporating L1 proteins from more HPV subtypes, exploring adjuvants that reinforce cellular immune responses to eradicate HPV-infected cells, and developing therapeutic HPV vaccines used either alone or in combination with other cancer therapeutic modalities might bring about a new era getting closer to the vision to get rid of HPV infection and related diseases. Herein, we summarize strategies for the development of HPV vaccines, both prophylactic and therapeutic, with an emphasis on the selection of antigens and adjuvants, as well as implications for vaccine efficacy based on preclinical studies and clinical trials. Additionally, we outline current cutting-edge insights on formulation strategies, dosing schedules, and age expansion among HPV vaccine recipients, which might play important roles in addressing barriers to vaccine uptake, such as vaccine hesitancy and vaccine availability.

Aerobic vaginitis is associated with carbonic anhydrase IX in cervical intraepithelial neoplasia

The aim of this study was to analyze the association between vaginal microbiota, carbonic anhydrase IX (CAIX) and histological findings of cervical intraepithelial neoplasia (CIN). The study included 132 females, among them 66 were diagnosed with high-grade intraepithelial lesion (CIN2, CIN3, and cancer), 14 with low-grade disease, and 52 assigned to the control group. An interview focused on the behavior risk factors, together with vaginal fluid pH measurement, wet mount microscopy, detection of Chlamydia trachomatis, and Trichomonas vaginalis were performed. After colposcopy, high-grade abnormalities were detected via direct biopsies and treated with conization procedure. Conuses were immuno-stained with CAIX antibody. The histological findings were CIN1 (n = 14), and CIN2+ (included CIN2 (n = 10), CIN3 (n = 49), and cancer (n = 7; squamous cell carcinomas)). Prevalence of bacterial vaginosis (BV) was similar between the groups. Moderate or severe aerobic vaginitis (msAV) was diagnosed more often among CIN2+ (53.0%) than CIN1 (21.4%). Moderate or strong immunostaining of CAIX (msCAIX) was not detected among CIN1 cases. Thus, msAV was prevalent in CAIX non-stained group (p = 0.049) among CIN2 patients. Co-location of msAV and msCAIX was found in CIN3. Regression model revealed that msAV associated with high-grade cervical intraepithelial neoplasia independently from smoking and the number of partners.

Human Papillomavirus (HPV) Infection and Risk Behavior in Vaccinated and Non-Vaccinated Paraguayan Young Women

Cervical cancer is a global health concern and ranks fourth among the most prevalent cancers in women worldwide. Human papillomavirus (HPV) infection is a known precursor of cervical cancer and preventive measures include prophylactic vaccines. This study focused on sexually active Paraguayan women aged 18-25 years, exploring the intersection of HPV vaccination and sexual behavior. Among 254 participants, 40.9% received the Gardasil-4 vaccine, with no significant differences in sexual behavior between the vaccinated and unvaccinated sexually active groups. However, a notable decrease in the prevalence of HPV among the vaccinated women highlights the efficacy of this vaccine in reducing infections. The prevalence of any HPV type was 37.5% in vaccinated participants compared to 56.7% in unvaccinated participants (p = 0.0026). High-risk HPV types showed a significant difference, with a prevalence of 26.0% in vaccinated women compared with 52.7% in unvaccinated women (p < 0.001). Although a potential decline in genital warts was observed among the vaccinated individuals, statistical significance (p = 0.0564) was not reached. Despite the challenges in achieving high vaccination coverage, the observed reduction in HPV prevalence underscores the importance of ongoing monitoring, healthcare professional recommendations, and comprehensive risk management. These findings contribute to dispelling concerns about HPV vaccination influencing sexual behavior, advocating further large-scale research to explore the impact of vaccines on various HPV types and potential cross-protection.

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.

Efficacy, immunogenicity and safety of HPV vaccination in Chinese population: A meta-analysis

Objective

To evaluate the efficacy, immunogenicity and safety of HPV vaccination in Chinese population.

Methods

PubMed, Embase, Web of Science and Cochrane Library from inception to November 2022 were searched to collect information on clinical trials of HPV vaccines. Database search strategy used a combination of subject terms and free terms. Studies were first identified by two authors through reading the title, abstract and full texts and, subsequently, based on the inclusion criteria: Chinese population, with at least one of the following outcomes (efficacy, immunogenicity, and safety), and HPV vaccine RCT, those eligible were included in this paper. Efficacy, immunogenicity and safety data, pooled by random effects models, are presented as risk ratios [95% confidence intervals (CI)].

Results

Eleven RCTs and four follow-up studies were included. Meta-analysis showed that HPV vaccine had good profile of efficacy and immunogenicity. The seroconversion rates were significantly higher among the vaccinated, uninfected (initial negative serum antibody) population than the placebo population for both HPV-16 (RR 29.10; 95% CI: 8.40-100.82) and HPV-18 (RR 24.15; 95% CI: 3.82-152.84), respectively. A significant reduction of the incidence of cervical intraepithelial neoplasia grade 1 (CIN1+) (RR 0.05; 95% CI: 0.01-0.23) and CIN2+ (RR 0.09; 95% CI: 0.02-0.40) was also measured. Risk for serious adverse events after HPV vaccination indicated comparable outcomes between vaccination and placebo.

Conclusions

For Chinese populations, HPV vaccines enhance the level of HPV16- and HPV18-specific antibodies and reduce the incidence of CIN1+ and CIN2+ in uninfected population. Also, the risk of serious adverse events in both groups are almost equivalent. More data are needed to establish vaccine efficacy with cervical cancer.